Screw Compressor Packages GEA Grasso M-Series. Operating Manual (Translation of the original text) P_261511_1

Transcription

1 GEA Grasso M-Series Operating Manual (Translation of the original text) P_261511_1

2 COPYRIGHT All Rights reserved. No part of this documentation may be copied or published by means of printing, photocopying, microfilm or otherwise without prior written consent of GEA Refrigeration Germany GmbH herein after referred to as the manufacturer. This restriction also applies to the drawings and diagrams contained in the documentation. LEGAL NOTICE These operating instructions are part of the technical documentation for the scope of delivery. They contain important instructions for ensuring safe and proper transport, installation, start-up, economic operation, maintenance and repair of the unit. Their observance helps in avoiding dangers, reducing repair costs and down-times and increasing the reliability and durability of the unit. These operating instructions are intended for the users of the equipment and are specifically intended for the operating company and its operating and maintenance personnel. It is essential that the operating company and its operating and maintenance staff read these operating instructions prior to transport, installation, startup, use, maintenance, repair, disassembly and disposal. This obligation to read also applies to personnel involved in activities in the life phases of the machine. The operating company must supplement these operating instructions with instructions regarding health and safety at work and environmental protection on the basis of existing national regulations for industrial safety. In addition to these operating instructions and the binding accident prevention regulations valid for the respective country and area where the product is used, the recognised technical regulations for safe and professional work must also be observed. These operating instructions are part of the unit. The entire documentation comprises these operating instructions and all additional operating instructions supplied with the unit. It must be kept readily available where the unit is installed. The entire documentation must also be forwarded if the unit is installed at another location and if the unit is sold. These operating instructions have been written in good faith. However, GEA Refrigeration Germany GmbH cannot be held responsible for any errors that this document may contain or for their consequences. The manufacturer reserves the right to make technical modifications during the course of further development of the equipment covered by these operating instructions. Illustrations and drawings in these operating instructions are simplified representations. As a result of the improvements and changes, it is possible that the illustrations do not exactly match the unit you are operating. The technical data and dimensions are subject to change. No claims can be made on the basis of them. The manufacturer cannot accept liability for damages which occur during the warranty period as a result of improper operating conditions and conditions of use, inadequate maintenance, improper operation, incorrect installation, incorrect or improper connection of the main electrical drive, or which result from or can be attributed to improper modifications or failure to observe the instructions; through the use of accessories or spare parts which were not supplied or recommended by the manufacturer. 2

3 SYMBOLS USED IN THIS MANUAL Danger! Stands for an immediate danger which leads to heavy physical injuries or to the death. Warning! Stands for a possibly dangerous situation which leads to heavy physical injuries or to the death. Caution! Stands for a possibly dangerous situation which could lead to light physical injuries or to damages to property. Stands for an important tip whose attention is important for the designated use and function of the device. 3

4 LAYOUT INFORMATION Bullet points and numbered list characters Bullet points are used to separate logical contents within a section: Bullet point 1 Types of bullet point 1. Bullet point 2 Types of bullet point 2. Numbered list characters are used to separate enumerations within a descriptive text: Descriptive text with consecutive numbering: Numbered list point 1 Numbered list point 2 Handling instructions Handling instructions require you to do something. Several consecutive steps result in a handling sequence that should be run in the specified order. The handling sequence can be divided into separate steps. Handling sequence 1. Handling sequence step 1 step 1, step 2, step Handling sequence step 2 The subsequent handling sequence is the expected result: Result of the handling sequence. Individual handling steps Individual handling steps are marked thus: Individual work steps 4

5 TABLE OF CONTENTS 1 BASICS Importance of the documentation Requirements for personnel, obligation to exercise due care Legal foundations (Germany) Specified Use Warning against foreseeable abusive use CE mark 15 2 MANUFACTURER INFORMATION 16 3 CUSTOMER SERVICE Technical customer service department Spare parts Training courses Service contracts 17 4 SAFETY General information for safety Behaviour in the case of emergency Possible residual hazards Installation in explosive atmospheres, installation zones 1 and TRANSPORT, STORAGE General instructions Delivery Transport (crane transport) Bearings Storage (several years) 24 6 INSTALLATION Basic information for installation Rigid installation Anti-vibration mounting Electrical connection Use in explosive atmospheres, installation zones 1 und Sound insulation, weather protection Information regarding noise emissions 27 7 DESCRIPTION OF DESIGN AND FUNCTION Installation in explosive atmospheres, installation zones 1 und Product code of screw compressor packages - Grasso SP1, SP2, SPduo and M Series Technical specifications Location of the product identification (name plate) Information and safety labels on the product Labelling of the pressure and temperature sensors, heater Label of the safety valve Labels of the screwed connections with DiNova ring Labels of the pipelines Marking the direction of rotation of the compressor drive motor Marking the direction of rotation of the oil pump motor Labels of the pressure gauge Labeling of the control / control cabinet Designation of the earth connection Process flow diagram Main components Screw compressor Compressor drive motor Compressor with coupling housing Oil separator OMC block with oil filter system Oil cooler Oil pump (optional) Suction filter - check valve combination Controller Fittings Safety devices 44 5

6 Monitoring devices Components installed by the client General functional description Refrigerant circuit Oil System Oil separation Oil heater Oil cooling Oil filter Oil pump Oil injection Oil circuit, OMC block Capacity control Technical specifications Designed for use in explosive atmospheres! Basic terms Operating media Refrigerant Refrigeration machine oils Secondary refrigerant Operating limits Water quality requirements, parameters 50 8 START-UP Important information for start-up Basics Connecting the screw compressor package Connecting the pipes Electrical connection Paint and insulation Start-up procedure Checking the electrical connection Leak test Drying, vacuum Operating position of valves Oil charge Pressure compensation with the cooling system Checking the direction of rotation of the oil pump motor Checking the fault monitoring Checking of the safety pressure limiter Checking of the emergency-off button Adjustment of oil pressure Checking the direction of rotation of the drive motor Mounting the coupling Checking the water circuits Initial start-up Checking the adjustment of the control slide Checking the control slide adjustment times Checking the oil cooler Adjusting the amount of injection oil and the oil temperature Screw compressor packages without refrigerant injection Compressor units with refrigerant injection Start-up after long standstill periods Restarting after approx. 1 year standstill 64 9 USE, OPERATION, CONTROL Use in explosive atmospheres, installation zones 1 and Important information for the operator Prerequisite for switching on Overview of the operating modes Setting of setpoint and limiting values as well as safety devices Operation of the screw compressor package Instructions regarding failures, their causes and remedies CLEANING, MAINTENANCE, REPAIR Use in explosive atmospheres, installation zones 1 and

7 10.2 Important information for service personnel Cleaning the heat exchanger Mechanical cleaning Chemical cleaning Maintenance General instructions Repair work Repair information Repairs of pressure vessels subject to approval inspection Maintenance intervals Maintenance work Maintenance of the screw compressor Changing the block mounting filter element Replacing the oil filter Maintenance of the suction filter Oil draining, oil filling, oil change Oil pump maintenance Changing the fine oil separation cartridges Tightening screw fastenings Coupling maintenance Checking the function of check valves Searching for leaks on the refrigerant side / leak test Venting the refrigerant circuit Refrigerant evacuation Checking the bearing noise Checking the solenoid valves for capacity control Checking the oil heater Maintenance of the compressor drive motor Checking the start regime Checking the safety devices Checking the operating parameters Maintenance of the switching cabinet Checking the earth connection Insulation Check of the tightening torque on the adjusting elements of the fixing base DECOMMISSIONING Shut-down in the event of dangerous situations Standstill for a period <48 hours Standstill for a period >48 hours Measures during shutdowns Monthly measures during standstill Four weeks before restarting DECOMMISSIONING, DISPOSAL 86 7

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9 TABLE OF FIGURES fig. 1 CE mark 15 fig. 2 Designation of the lifting points 21 fig. 3 Stopper with shackle 22 fig. 4 Transportation with a wire rope hoist 22 fig. 5 transportation using crossbeam 23 fig. 6 Location of the product identification (type plate) 33 fig. 7 Type plate 33 fig. 8 Safety labels of the pressure and temperature sensors, heater 34 fig. 9 Label of the safety valve 34 fig. 10 Labels of the screwed connections 34 fig. 11 Labels of the pipelines 35 fig. 12 Marking the direction of rotation of the compressor drive motor 35 fig. 13 Marking the direction of rotation of the oil pump motor 35 fig. 14 Labels of the pressure gauge 36 fig. 15 Test verification for the control system 36 fig. 16 Designation of the earth connection 37 fig. 17 Process flow diagram Grasso SP1, M-series 37 fig. 18 Main components of the GEA Grasso M-Series 38 fig. 19 GEA Grasso M-Series, arrangement of the SCP 39 fig. 20 GEA Grasso M-Series, arrangement of the compressor drive motor 39 fig. 21 GEA Grasso M-Series, arrangement of the coupling housing 40 fig. 22 GEA Grasso M-Series, arrangement of the oil separator 40 fig. 23 GEA Grasso M-Series, arrangement of the OMC block with oil filter system 41 fig. 24 GEA Grasso M-Series, arrangement of the oil cooler 41 fig. 25 GEA Grasso M-Series, arrangement of the (optional) oil pump 42 fig. 26 GEA Grasso M-Series, suction filter - check valve combination 42 fig. 27 GEA Grasso M-Series, arrangement of the controller 43 fig. 28 Corrosion resistance in presence of chlorides 51 fig. 29 Vacuum required to remove moisture from refrigerating plants 56 fig. 30 Stop valve open 57 fig. 31 Stop valve closed 57 fig. 32 Check valve 57 fig. 33 Shuttable check valve 57 fig. 34 Control valve 58 fig. 35 Shuttable check valve 58 fig. 36 Solenoid valve 58 fig. 37 Change-over valve 58 fig. 38 Oil pressure control valve 58 fig. 39 Overflow valve, safety valve 59 fig. 40 Pressure controlled check valve 59 fig. 41 Quick acting valve, spring-loaded 59 fig. 42 Charging valve, drain valve 59 fig. 43 Service valve 59 fig. 44 Oil temperature limiter 60 fig. 45 Temperature controlled control valve 60 fig. 46 Motor direction of rotation 62 fig. 47 Arrangement of MIN / MAX sight glasses 78 fig. 48 Operating position of the fine oil separation cartridges 79 9

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11 1 1.1 Basics BASICS Importance of the documentation These operating instructions are part of the technical documentation for the Grasso scope of delivery. It contains advice for operating the package/chiller safely, properly and economically. The observance of the operating manual helps in avoiding dangers, reducing repair costs and down-times and increasing the reliability and durability of the package/chiller. This operating manual is directed at the users of the package/chiller and is specifically intended for the operating company and its operating and maintenance personnel. This operating manual must be read prior to transport, installation, commissioning, maintenance, repair, disassembly/disposal. applicable international and national standards, applicable occupational safety regulations, applicable accident prevention regulations, applicable environmental protection regulations, the construction and functioning of the unit, recognised technical regulations for safe work according to good professional practice. The technical personnel must: be able to assess the work assigned to them, recognise and avoid possible dangers, be authorised by those responsible for the safety of the system to carry out the requisite work and activities. All work explained in this operating manual must only be carried out by technical personnel. Caution! This operating manual must be supplemented with instructions based on prevailing national regulations regarding industrial safety, health protection and environmental protection. No arbitrary changes may be made to the control or other components belonging to the unit. Maintenance work may only be done by authorised service staff. In addition to this operating manual and the mandatory accident prevention regulations applicable for the respective place of installation, the accepted technical regulations for safe work according to good professional practices must also be observed. The operating manual is a part of the total product. The entire documentation, consisting of this operating manual as well as all supplied additional instructions, is to be always kept easily accessible at the place of installation of the package/chiller. The complete set of documentation must also accompany the package/chiller if it is sold. 1.2 Requirements for personnel, obligation to exercise due care Qualification All work explained in this manual (assembly, electrical connection, commissioning, operation, etc.) may only be carried out by trained technical personnel who observe the relevant technical regulations. Technical personnel are representatives of the unit manufacturer and persons who, as a result of their technical training, experience and personal instruction in training measures, have sufficient knowledge of: Special requirements for the electrical technicians Work on electrical components and modules may only be carried out by an electrical technician according to the rules relevant to electrical engineering. Furthermore the operator has to take care that the electrical systems, tools and fixtures are operated according to the rules relevant to electrical engineering and applicable standards and serviced properly. In principle it is prohibited to carry out work on parts under voltage. Fuses may only be replaced and not repaired or bypassed. Only the fuses specified in the electrical circuit diagram may be used. A two-pole voltage tester must be used to ensure that the parts are de-energised. The power supply as well as the unit casing must be sufficiently grounded and tagged with a suitable label. Deficiencies noticed in the electrical systems/ modules/tools and fixtures must be corrected immediately. If an acute danger exists till then, 11

12 Basics the package/chiller must not be operated in the defective condition. Accident Prevention Regulation including implementation regulations (BGR 500, chapter 2.35) on refrigeration plants, heat pumps and cooling equipment (BGV B3) regarding noise EN Refrigerant fittings, safety related technical definitions, testing and marking DIN 2405 Pipes in refrigeration plants, marking VDMA specifications,in particular VDMA and VDI Guidelines Instruction sheets for handling ammonia, Instruction sheet for halogenated hydrocarbons containing fluorine BGI 648 Safety data sheet for ammonia and other refrigerants and refrigeration oils Minimum age The minimum age for the operation of the package/ chiller and installation is 18 years. All persons involved in the assembly and installation of the package/chiller and the system must get themselves trained at regular intervals and/or familiarise themselves with the current technical data of the device. The training and instructions is to be conducted at least once a year, unless some other interval has been agreed upon with the manufacturer. Obligation to exercise due care The statutory regulations for meeting the obligation to exercise due care are to be observed. Meeting the obligation to exercise due care according to the current level of technology requires that everything that is technically possible (use of accepted technological rules) and economically reasonable The list of rules and standards has been taken from Status Report No. 5 of the German Refrigeration and Air Conditioning Engineering Association "Safety and environmental protection in ammonia refrigeration plants" and also fully applies to other refrigerants. Danger! be done to prevent damage in a protectively safe manner. 1.3 Legal foundations (Germany) The additional safety instructions as defined in "Appendix E" must be observed for packages for the designated use in potentially explosive atmospheres, installation zones 1 and 2 in accordance with EN The following standards, regulations, ordinances and laws must be strictly observed to ensure the safety and functional reliability of the packages and chillers: EC Machinery Directive 2006/42/EC EC Pressure Equipment Directive 2014/68/EC AD 2000 Info Sheets The following: Hazardous Incident Ordinance (12. BlmSchV) with 1st failure VwV standards, safety regulations, Federal Pollution Control Act (BImSchG), 4th BimSchV guidelines and recognised engineering practice, Water Resources Act (WHG), VawS Hazardous Substances Ordinance (GefStoffV) Recycling and Waste Management Act (KrWAbfG) DIN EN 378, Part 1 to Part 4 Safety-related technical requirements and environmental requirements 12 listed in these operating instructions must be observed at least! If the package/chiller is used in a country other than Germany, the rules and regulations applicable at the place of installation must be observed and complied with! The mandatory accident prevention regulations applicable for the respective country and area where the product is used must also be observed.

13 Basics Failure to observe the safety instructions can lead to danger to personnel and the environment as well as damage to the unit. 13

14 Basics 1.4 Specified Use the manufacturer is responsible for all personal injury and damage to property resulting from improper use. Observe the "Specified Use" chapter of the installation instructions for the screw compressor! The pressure equipment is not designed for dynamic loads. If there is a risk of lightning strikes, the pressure equipment must be earthed. The supplier/installer must record instructions for regular inspection of the pressure equipment in his operating manual and must specify the procedure to be followed by the end user in the event of damage. In order to prevent burns or frostbite, the pressure receptacle must not be touched during operation. This can be prevented by respective safety measures. Appropriate warning signs must be affixed. Compressor units or systems must be equipped with safety valves in accordance with EN 378. The foundation must provide sufficient rigidity. The screw compressor package must only be operated up to a maximum discharge pressure in accordance with the type plate. It is imperative that you comply with the applicable conditions of use with respect to pressure and temperature for the screw compressor package. Do not change the setting values of the safety pressure switch. This would endanger the operating safety of the refrigeration plant. If the switch-off value is set higher than 0.9 x maximum operating pressure (see EN378-2) of the high pressure section of the refrigerating system, this may result in the the tank within this section of the system rupturing. The operating regime stipulated by the manufacturer, especially for the starting phase of the screw compressor package, must be observed. Operating parameters must be monitored. Operating parameters must not deviate from within the defined limits. The screw compressor package has been designed and manufactured for a specific application under defined conditions of use. Unauthorised structural modifications are not permitted. We assume no liability for any resulting damage or injury. In the interest of further development, GEA Refrigeration Germany GmbH reserves the right to make technical modifications. The screw compressor package described here corresponds to the state of the art at the time this operating manual was published. The manufacturer must be consulted in all cases as to the permissibility of the modification if there is any change of the application or the conditions of use. The supplier/installer must carefully install the accessories for the pressure equipment. The pressure equipment must not be damaged during installation and must be painted after installation. The pressure equipment must only be filled with the refrigerant specified in the contract. The pressure units must be installed in the compressor unit or the system in such a way that vibrations or pulses cannot be transferred to the pressure units. The contacts must be installed with the power supply disconnected. Specified use includes observance of this manual and all supplied operating manuals as well as compliance with the maintenance and service intervals and conditions stipulated therein. Warranty claims and authorisation for operation become void if the equipment is not used for its specified purpose. 1.5 A package/chiller is said to have been abused, if Do not make any modifications to the screw compressor package and the compressor control system. 14 unauthorised refrigerants, fuels and lubricants and secondary refrigerant materials are used. These may impair the safety and functionality of the SCP. They will also void the guarantee. The pressure equipment described here must not be used for any purpose other than the purpose specified here. The units must only be installed by the supplier/installer and not by the end user. If the pressure equipment is not used according to the regulations, the safe use of the equipment is not guaranteed. The supplier/installer or the operator and not Warning against foreseeable abusive use Observe specification for the project! electrical components are wrongly connected. Watch voltage and frequency! mechanical components are wrongly connected.

15 Watch pressure and temperature! the supporting, hanging and storage facilities are misused. control and regulation units including control system software are tampered with. the driving power generated by the motor is used for purposes other than the operation of the respective compressors and pumps. Basics 1.6 CE mark By affixing the CE mark, the manufacturer confirms the conformity of the product with the applicable EC Directives and compliance with the principle requirements stipulated within them. fig.1: CE mark The CE mark is affixed to the nameplate. The CE mark for products from GEA Refrigeration Germany GmbH is provided as defined in the Pressure Equipment Directive, i.e. pressure equipment is placed on the market with the required equipment parts with safety function. This complete assembly is subject to the Pressure Equipment Directive. 15

16 Manufacturer Information 2 MANUFACTURER INFORMATION GEA Refrigeration Germany GmbH is a company within GEA Refrigeration Technologies, the Refrigeration Technology Segment of the GEA Group and provides its customers around the world with highquality components and services for refrigeration and process technology applications. Locations: GEA Refrigeration Germany GmbH Factory Berlin Holzhauser Str Berlin, Germany Tel.: Fax: Web: refrigeration@gea.com GEA Refrigeration Germany GmbH Factory Halle Berliner Straße Schkopau/ OT Döllnitz, Germany Tel.: Fax: Web: refrigeration@gea.com 16

17 3 Customer service CUSTOMER SERVICE GEA Refrigeration Germany GmbH supplies products of high quality and reliability. In addition, the manufacturer ensures continuous operation of the refrigeration and process technology system and provides exceptional service for the components supplied. In most cases, you will receive your spare parts within 24 hours after placing the order. You can contact us using the following hotlines: +49 (0) Technical customer service department Do you require support from the technical customer service department? Specially trained, experienced service technicians are available on call for you in order to provide assistance in case of technical problems and to offer support in the framework of our after-sales service. Wireless, out of hours Landline, weekdays from 8 to 17 hour +49 (30) Fax +49 (30) Grasso-parts@geagroup.com Order spare parts from our G-Pos. online shop 24/7 Hotline: (Grasso Parts online shop) the hotlines can reached around the clock on every day of the week: gea-refrigeration.de.spareparts@gea.com Wireless 3.3 Training courses +49 (0) Warning! Landline, weekdays from 7 to 17 hours All work on our systems must only be carried out by technical personnel! Acquire the technical know-how required for this in good time! +49 (30) (30) Grasso-service@geagroup.com local sales office Comprehensive training courses are held regularly for service technicians and mechanics, thus ensuring the safe and proper use and maintenance of our systems. outside of Germany, Austria and Switzerland please contact: Grasso-service@geagroup.com technical support for liquid chillers with reciprocating compressors in Germany, Austria and Switzerland 24/7 Hotline +49 (345) The specialists of our Technical Customer Service department support you in installations, acceptances, maintenance, operating questions, on-site inspections and repairs of our products. 3.2 Spare parts 3.4 Service contracts It is possible to sign a long-term service agreement (service contract). For further information regarding the content, scope and conditions of the possible service options, please contact the Technical Customer Service department. Grasso-service@geagroup.com GEA Refrigeration Germany GmbH has its own practical and rapidly working spare parts department to supply the necessary spare parts worldwide. Necessary spare parts are shipped as quickly as possible. 17

18 Safety 4 SAFETY General information for safety Warning! Despite careful design of the machine and implementation of all the safetyrelevant regulations, further risks for persons and machine during all life phases of the package/chiller cannot be fully ruled out. The additional safety instructions in the individual chapters of this manual must therefore be carefully observed! The safety aspects to be observed for operating the equipment are shown in the chapter on "Safety". The equipment has been developed and manufactured according to the currently applicable state of the art and is reliable in operation. It has been tested and left the factory in a technically faultless safe condition. In order to maintain this condition for the operation time, the details of the project documentation and certificates must be observed and complied with. When operating the equipment, at least the general safety regulations and the provisions and guidelines referred to in this documentation must be observed. Residual risks that were ascertained during the risk assessment carried out for the product according to safety standard EN ISO Safety of Machines - are: Only compliance with all provisions and guidelines will enable optimum protection of the personnel as well as dangers to the environment and the safe and smooth operation of the equipment. 4.2 Possible residual hazards mechanical hazards due to sharp sheet metal edges and projecting parts, electrical hazards as a result of inadvertently coming in contact with terminals and cables, thermal hazards as a result of inadvertently coming in contact with heat exchangers and pipes, exposure to noise, Familiarise yourselves with the local evacuation plan before beginning the work. hazards caused by vibration due to improper installation, hazards due to working materials and other materials in case of allergies orthe like, neglect of ergonomic principles, combinations of various hazards, unexpected start-up, unexpected rotation in case of incorrect electrical connections or defects, Behaviour in the case of emergency Should an emergency situation arise despite adhering to the safety regulations, the package/chiller must be shut down immediately and isolated from the electrical mains. The mains cable must be blocked in such a way it is not possible to restart the unit accidentally and marked as such. The operator of the complete system has to take care that an isolation device, e.g. a mains switch with appropriate contact rating and an integrated indicator, is pre-installed in the mains cabling on site. shut-down, emergency stop when defects are detected, changes to the rotational speed, power failure, A separate mains cable/feed cable must be laid for the operation of the package/chiller. failure of the control circuit or control loop, incorrect assembly, fracture during operation, operating media or objects getting thrown out, loss of stability and personnel slipping, tripping or falling. The mains cable/feed cable is to be specially protected and provided with an emergency stop switch. 18

19 Safety lutely necessary to ensure a minimum oil level above the heating elements. To this end, a separate oil level switch is used in each use case according to the necessary explosion protection specification. There are no radiation hazards 4.4 Installation in explosive atmospheres, installation zones 1 and 2 Danger! The additional instructions for using screw compressor packages in explosive atmospheres, installation zones 1 and 2, must be complied with! Operation The same regulations apply in regard to the operating instructions for screw compressor packages in potentially explosive atmospheres as described in the applicable operating manual. In addition to this, the following extensions apply: Function and Design The same functional and design characteristics apply to the maintenance instructions for the use of screw compressor packages in potentially explosive atmospheres as described in the respective applicable operating manual. The owner operators regulations must also always be observed see also section: Safety information for compressor, Appendix E, and for package, Appendix E. In addition to this, the following extensions apply: All components relevant for the use of screw compressor packages in relation to their use in potentially explosive atmospheres (concerns both electrical and non-electrical components) are separately designed and documented! The extended documentation scope (component descriptions, certificates, calculations) is part of the product documentation. Extension to the method of working The use of screw compressor packages is extended to use in potentially explosive atmospheres, including the compression of process gases (only compression for the purposes of pressure increase). The screw compressor packages are not suitable for pumping potentially explosive mixtures. This means that, when the compressor is in intake condition, the pumped liquid must not contain any oxygen. The intake condition always refers to pressure layers in the overpressure range. The electrical engineering regulations for installations in potentially explosive atmospheres, especially EN , apply to the installation and connection of electrical components. The relevant prescribed cabling material must be used. The whole screw compressor package must be earthed by the owner operator. Maintenance The same regulations apply to the maintenance of screw compressor packages in potentially explosive atmospheres as described in the respective applicable operating manual. In addition to this, the following extensions apply: In addition, the legal safety regulations for the installation of the screw compressor packages apply to the people responsible for the maintenance of the screw compressor package with respect to the maintenance of individual components or assemblies or their complete replacement in potentially explosive atmospheres. The maintenance may only be carried out in agreement/with the knowledge and release of the owner operator. The owner operator and the system builder must use monitoring devices reflecting the respective state of the art standards to positively monitor and ensure this effect. Safety equipment extension In addition, the legal safety regulations apply to the people responsible for operating the screw compressor package, and must be complied with respect to the transport, assembly, operation and maintenance and if necessary the replacement of subassemblies, etc. in potentially explosive atmospheres. If oil heaters are used in potentially explosive atmospheres (see component specification), additional, separate oil level monitoring is abso- 19

20 Safety The maintenance and replacement regulations resulting from the operating manual for the components must be conformed with. Appropriate special tools approved for the potentially explosive atmosphere must be used. Only original spare parts may be used. If original spares are not used, the guarantee is invalidated or the owner is liable in the event of damage. Each maintenance inspection (see maintenance book) must also include checking the secure fit of the threaded connections for the coupling safety hood. 20

21 5 Transport, Storage TRANSPORT, STORAGE General instructions Caution! Adequate lighting must be ensured during loading and unloading as well as for storage in order to avoid injuries and damage to property. There is a danger of impacts and stumbling due to protruding parts on the equipment (e.g. valve caps). There is also the danger of being cut on sharp edges and surfaces. There is a danger of crushing parts of the body during the transport work. Personal protective equipment (work clothing, work books, gloves) must be worn during all activities on the equipment. Shipment is made in the type of packing stipulated in the order. The screw compressor package is generally supplied without packing. The screw compressor package has an inert gas filler in the refrigerant circuit. Warning! The compressor(s) of the screw compressor package is/are not filled with oil. The screw compressor package must not be started, therefore, before proper assembly and start-up. 5.3 All work explained in these operating instructions must only be carried out by qualified personnel. Transport (crane transport) Warning! The screw compressor packages are not intended for transport with a fork lift truck! These operating instructions must be read prior to transport, storage and delivery to the installation site. It is imperative to strictly observe the instructions and information given! Delivery Screw compressor packages are high-quality products, which must be handled with due care during transport. Protect the equipment from impact and set it down carefully. When transported by crane, the screw compressor package must have the same position as in operation (frame downwards!). Only use the lifting points provided. The lifting points are marked! fig.2: Designation of the lifting points Caution! It is forbidden to attach SCPs to fittings or pipes or at the eyebolts / lifting rings of the compressor, the electric motor, the tank or the switching cabinet. 21

22 Transport, Storage Take special care not to attach the ropes near to small nominal diameter pipes or insulation and to damage them. Use spacers if necessary. The lifting points are not arranged on one plane. The ropes must be longer than 3 m. The height differences between individual lifting points must be compensated by suitable extensions. Make suitable arrangements (timber or insulating material) to avoid damage to the surface. Shackles must be used. fig.3: Stopper with shackle fig.4: Transportation with a wire rope hoist 22

23 Transport, Storage 5.4 Bearings When the screw compressor packages are delivered, check for possible transport damage and report any damage to the manufacturer in writing. The storage area of screw compressor units shall be roofed, plain and paved and secured against access of unauthorized persons. Place the screw compressor package onto timber planks and have it protected from jerks or impacts. Warning! Screw compressor packages must be adequately protected from external influences (humidity, frost, extreme heat) during storage. This usually concerns lengthy standing times outdoors before installation and start-up of the refrigeration plant. The manufacturer recommends the use of plastic sheeting to cover the whole product. The venting slits of the electric motors must always be covered! Storage temperature: 5 C C fig.5: transportation using crossbeam Danger! Make certain there is no one under the suspended load during transport with the crane! Position the screw compressor package on the transport vehicle such that it is prevented from tilting and falling. Load securing is preferably carried out by lashing to the specified points. The pipes and equipment of the screw compressor package must not be entered. Components must be secured against vibrations. The competent staff member or the company itself is responsible for ensuring safety during transport. Warning! Screw compressor packages must be adequately protected from external influences during transport. Transport packaging (optional): foil The foil may only be removed before erecting the screw compressor package at the intended installation location in the machine room. Up until this point in time, the foil serves to protect the screw compressor package against external influences. The composition of the paint on the screw compressor package is designed for installation in the machine room (inside installation). Contact with water (including water spray) must be avoided. Warning! The screw compressor package is filled with dry gas (e.g. nitrogen) before delivery which prevents any change of the properties of any already filled operating medium (e.h. refrigerating machine oil). Check the gas filling once a week and recharge to the specified overpressure if required. Turn the shaft of the compressor at least every four weeks (approx. 10 revolutions). The transport packing (foil if present), that needs to be opened for turning the compressor shaft and for checking the gas filling, must be closed again after carrying out the activities in order to ensure protection against external influences. The packing (foil if present) must be replaced as needed and for lengthy storage times. 23

24 Transport, Storage Warning! 2. Air humidity < 50% Regular ventilation of the screw compressor package packaging (if present) must be ensured in order to prevent condensation on the surfaces of the machine. If the screw compressor package is intended to be stored, the following preparatory measures must be carried out ex-works (especially protection against internal and external corrosion): Long-term storage With a standstill of the compressor of more than 16 weeks prior to start-up, there is a danger that the shaft seal may stick on the shaft and therefore be damaged on start-up. Because of this, removal and cleaning of the shaft seal is mandatory in order to ensure that it functions correctly. All process connections on the screw compressor package are sealed tight. The screw compressor package is charged with dry gas to 1 bar. A suction pressure gauge has been installed. The facing sides of the mounted coupling hubs have been greased. (Does not apply to sliding bearing compressor drive motors) 1. Use two pressure screws to remove the cover of the shaft seal, including the stationary gasket inserted in it. In case of the use of high-voltage motors: the operating manual of the manufacturer is to be followed, especially regarding any anti-condensation heater required. 2. Removal of the seal package arranged on the shaft with the associated slide ring by hand or, if tightly seated, extraction by means of an appliance. If the seating is loose, the seal package may adhere to the stationary seal and will be pulled out when removing the cover. 3. Clean the shaft seat with a lint-free cloth. Grease it lightly and push the sealing package back onto the shaft again. 4. After pushing onto the shaft, the seal package must be manually compressed against the spring pressure which acts on it. At the same time, it must be checked whether the gasket springs out again. 5. Then re-fit the cover of the shaft seal. Warning! Danger of cuts and crushing injuries. 6. If storage is longer than 26 weeks, all O-rings must be renewed. 5.5 Storage (several years) The instructions in the "Transport, storage" chapter must be heeded. Free-standing motor and main flow shafts have been conserved. The space on the screw compressor for the shaft seal has been greased. The connections on the oil cooler water side have been sealed. The following maintenance work must be carried out at the storage location during storage: 1. Visual inspection of the general condition of the screw compressor package. 2. Cyclical rotation of the screw compressor shaft (about 10 revolutions per month and the compressor drive motor (see operating manual). Does not apply to sliding bearing compressor drive motors. 3. Check the transport fill pressure with a pressure gauge at the connection of item 405 (see P+I flow chart). If this value < 1 bar, replenish dried gas via the valve of item 85 (see P+I flow chat). All valves are already opened at the factory for a common pressure range. The following storage conditions must be maintained when storing screw compressor packages that are equipped with a control. 1. Storage temperature > 10 C 24

25 Transport, Storage Caution! After completion of the storage period and prior to re-delivery, a general review in the factory or a general examination at the storage location, performed by the technical customer service technician of GEA Refrigeration Germany GmbH, is recommended. Please pay attention to the information in the "Start-up" chapter. The general check includes changing the O-ring on the compressor shaft seal as well as replacing the shaft seal of the oil pump. 25

26 Installation INSTALLATION misalignment 0.25 mm) at the coupling is attained again. Then tighten the foundation bolts. Basic information for installation Caution! 6.3 During the installation, make sure that substances escaping from leaks do not reach into the soil, groundwater or surface water. The applicable legal regulations must be heeded at the place of installation (e.g.for Germany: German Federal Water Act WHG). Anti-vibration mounting The frame of the screw compressor unit must be aligned with the levelling bolts until the coarse alignment (radial and angular misalignment (radial and angle offset 0.25 mm) at the coupling is attained again. Before tightening the foundation bolts of the isolators, check that the isolators over the spring (predominantly made of rubber) are free and do not lie on the foundation. All foundation calculations, the selection of materials and the soil analysis are the designer's or owner s responsibility. A plan must be produced for proper and professional assembly prior to the installation. The electrical and operating media connections must be established. It must be borne in mind that, in addition to the installation area of the screw compressor package, there must be sufficient space available for the pipes as well as for operating during maintenance activities. 6.4 Electrical connection Danger! Contact with live components is prohibited. Produce the earth connection according to the designation in the general assembly drawing. See chapter "Designation of the earth connection". Install the screw compressor package on a level surface. The difference from the horizontal must not be more than 0.3 %. Provide enough space for maintenance work. Under normal conditions, the screw compressor package stands solidly on the installation surface due to its own dead weight. We recommend that you provide ribbed rubber plates for shock absorption between the support surface and screw compressor package feet or machine base frame. Before starting work, make sure that all parts to be connected are de-energised, e.g. by removing the main fuse in all phases or installing a jumper wire. The insulation resistance of the electrical tools and fixtures and wiring is to be checked. The connection may only be undertaken if this value lies in the allowable range. If greater damping is required (installation on a floor ceiling or on the roof), vibration dampers must be provided. The appropriate type of vibration damper must be determined and realised for this case. Also decouple the secondary refrigerant lines using compensators when vibration absorbers are used. All electrical connections must be established and all electrical consumers/sensors must be connected according to the circuit diagram. The welding seams must be inspected in accordance with the Pressure Equipment Directive after welding work by the customer or operator on pipe line connections and flanges. 6.2 Rigid installation The frame of the screw compressor unit/ liquid chiller is placed on foundation bolts on a prepared foundation. The frame must be levelled with suitable shims such that the coarse alignment (radial and angular 26

27 6.4.1 Use in explosive atmospheres, installation zones 1 und 2 Installation The manufacturer will not accept liability for damage due to incorrect outdoor installation. Danger! The same regulations apply to the operating instructions for screw compressor packages in potentially explosive atmospheres as described in the respective applicable operating manual. In addition to this, the following extensions apply: 1. The relevant electrical engineering regulations for installations in potentially explosive atmospheres, especially EN , apply to the installation and connection of electrical components. Relevant prescribed cabling material must be used. 2. The whole screw compressor package must be earthed by the owner operator. 6.6 Information regarding noise emissions The noise information provides approximate parameters and apply to the installation without any secondary noise protection measures. The information has a tolerance of ±3 db. The precise data depend closely on the emission values for the motors, which are manufacturer dependent. Should local conditions require adherence to noise levels, a calculation should be made using the specific motor data in individual cases. Sound insulation measures, such as motor encapsulation or complete package encapsulation can achieve a significant reduction in sound level. Wearing hearing protection with sufficient noise reduction is recommended in rooms with running screw compressor packages. Caution! 6.5 Sound insulation, weather protection If the screw compressor package is intended for outdoor installation, it must be provided with a suitable housing for sound insulation and weather protection by the customer. The weather protection must provide the machine with adequate protection against the climatic conditions at the installation location. According to EU Directive 2003/10/EC, the allowable exposure limit value regarding the daily noise exposure level is 80 db(a). In the event of noise levels above this limit value the system operator must provide the operator with information on exposure to noise and personal hearing protection and ensure that this is also worn (2003/10/EC Article 6). The screw compressor package is not intended for unprotected outdoor installation. Protection against external influences, especially dirt, dust and moisture (wetness), is essential. 27

28 Installation Sound power level L WA in db(a) Compressor drive motor output in kw Compressor type/theoretical throughput volume in m 3 /h at 4500 RPM H 721 L 833 M 1056 N Max Min Max Min Max Min Max Min Max Min Max Min Max Min Max Min Max 111 Min

29 7 7.1 Description of Design and Function DESCRIPTION OF DESIGN AND FUNCTION Installation in explosive atmospheres, installation zones 1 und 2 Danger! The same functional and design characteristics apply to the maintenance instructions for the use of SCPs in potentially explosive atmospheres as described in the respective applicable operating manual. In addition to this, the following extensions apply: 1. All components relevant for the use of SCPs in relation to their use in potentially explosive atmospheres (concerns both electrical and non-electrical components) are separately designed and documented see product description! 2. Extension to the method of working The use of SCPs is extended to use in potentially explosive atmospheres, including the compression of process gases (only compression for the purposes of pressure increase). The SCPs are not suitable for pumping potentially explosive mixtures. This means, when the compressor is in intake condition, the pumped liquid must not contain any oxygen. The intake condition always refers to pressure layers in the overpressure range. The owner operator and the system builder must use monitoring devices reflecting the respective state of the art standards, to positively monitor and ensure this effect. 3. Safety equipment extension If oil heaters are used in potentially explosive atmospheres (see also component specifications in the product description) additional, separate oil level monitoring is absolutely necessary to ensure a minimum oil level above the heating elements. To this end, a separate oil level switch is used in each use case according to the necessary explosion protection specifications see also the component specifications in the product description. 29

30 Description of Design and Function 7.2 Product code of screw compressor packages - Grasso SP1, SP2, SPduo and M Series X Y Model size screw compressor package The ND screw compressor will be provided for the screw compressor packages in the Grasso SP2 series (two-stage). Versions of the screw compressor package 9 Screw compressor version variations A (X1) Oil cooling Screw compressor size HP side Only for screw compressor packages in the Grasso SP2 series (two-stage). X / (X1) Screw compressor package size Code letter Theoretical volume flow Code letter Theoretical volume flow at 2940 min -1 in m³/h at 2940 min -1 in m³/h C 231 T 1460 D 265 V 1740 E 321 W 1940 G 372 Y 2390 H 471 Z

31 Description of Design and Function Code letter Theoretical volume flow Code letter Theoretical volume flow at 2940 min -1 in m³/h at 2940 min -1 in m³/h L 544 XA 3250 M 690 / 708 XB 4150 N 860 / 870 XC 4900 P 805 XD 5800 R 1040 XE 7170 S 1290 XF 8560 * Grasso M Series Y Screw compressor package version Design type Screw compressor package Refrigerant NH 3 Refrigerant R22 HFC Refrigerant Refrigerant R290 and R600a CO 2 and Special media Horizontal oil separator installed below A H R F O Oil separator installed vertically B K S G P Oil separator horizontally in series C L T Grasso SPduo/ mechanical suspension D M V Y W Grasso SP2 (two-phase) E N U 9 Screw compressor versions 1 Standard refrigerating compressor Vi = 1.8; 2.0; 2.2; 2.6; Standard refrigerating compressor Vi = Standard refrigerating compressor Vi = Standard refrigerating compressor Vi = Standard refrigerating compressor Vi = variable 6 Booster Vi = fixed 7 Heat pump compressor Vi = fixed or variable 31

32 Description of Design and Function Speed regulated Vi = variable A Oil cooling Code letter A B C D E F Oil cooling Water-cooled oil cooler Refrigerant cooled oil cooler Refrigerant injection Water and refrigerant cooled oil cooler Water or refrigerant cooled oil cooler and refrigerant injection Without oil cooler Examples of designation XA B - 6 A Singe stage screw compressor package Grasso SP1 with screw compressor 3250 m³/h (XA), refrigerant NH 3 and vertically installed oil separator (B), booster with fixed internal volume ratio (6)with oil fine separation and water-cooled oil cooler (A) T A - 2 A Singe stage screw compressor package Grasso SP1 or SSP1 with screw compressor 1460 m³/h (T), refrigerant NH 3 and horizontally installed oil separator (A), fixed internal volume ratio Vi = 3.6 (2) with oil fine separation and water-cooled oil cooler (A) N A - 3 B Screw compressor package Grasso M with screw compressor 873 m³/h (N), refrigerant NH 3 and horizontally installed oil separator (A), fixed internal volume ratio Vi = 4.8 (3)with oil fine separation and refrigerant-cooled oil cooler (A) LD - 2 A W E - 6 A (L) Screw compressor package Grasso SPduo with 2 of screw compressors 544 m³/h (L), refrigerant NH 3 and DuoPack version or multiple configuration (D), fixed internal volume ratio Vi = 3.6 (2) with oil fine separation and water-cooled oil cooler (A) Two-stage screw compressor package with LP screw compressor 1940 m³/h (W), refrigerant NH 3 two-stage package (E), LP-compressor as booster (6), with oil fine separation and water-cooled oil cooler (A), HP-compressor 544 m³/h (L) 7.3 Technical specifications Packages / chillers are designed and manufactured for special fields of application. For technical specifications see the following. order specification, list of parameters, general assembly drawing, P+I diagram. 32

33 7.4 Description of Design and Function Location of the product identification (name plate) Weight without filling: Weight of the screw compressor package when empty The type plate contains the most important technical data pertaining to the product. This data and the contractual agreements define the limits of designated use. Refrigerant: Information regarding the refrigerant used As standard, the type plate is fixed to the oil separator (deviations of the location are possible). Max. operating pressure: Information regarding the max. operating pressure Volume flow: Information regarding the volume flow The default languages are English and German fig.6: Location of the product identification (type plate) fig.7: Type plate GEA Refrigeration Germany GmbH Contact data of the manufacturer Type: Type designation of the screw compressor package Serial no.: Serial number of the screw compressor package Year of construction: Year of construction of the screw compressor package 33

34 Description of Design and Function 7.5 Information and safety labels on the product Label of the safety valve (safety labels) Danger! The safety-related labels on the package/chiller must be followed! fig.9: Labelling of the pressure and temperature sensors, heater (safety labels) Label of the safety valve Importance of the labels The safety valve must be connected to a blow-off line Labels of the screwed connections with DiNova ring (handling instructions) fig.8: Safety labels of the pressure and temperature sensors, heater Importance of the labels: Before replacing pressure and temperature sensors without dip tube, it must be ensured that the pipes into which the sensors are mounted are not pressurised. The pressure-free state can be achieved by closing the shut-off valves before the sensor to be replaced. Before replacing oil heater it must be ensured that the oil separator into which the oil heater is screwed in is not pressurised. Not applicable to oil heaters of the HLP type series. fig.10: Labels of the screwed connections The informative label for all screwed connections with DiNova ring (handling instructions) is attached to the electric motor in a clearly visible manner. Importance of the labels: If any leakage occurs at a screwed connection (escaping gases or vapours), the screwed connection must be tightened: Counter-hold the screwed pipe connection using a wrench. Tighten the pipe nut about 1/4 to 1/3 rotation beyond the point where the increase in the force if felt. The leakage is remedied. 34

35 Description of Design and Function Labels of the pipelines (information plate) Pipelines in refrigeration plants must be labelled as follows (DIN 2405): Refrigerant Direction of flow State of phase Marking the direction of rotation of the compressor drive motor (information plate) fig.11: Labels of the pipelines 1 Arrow head (indication of the direction of flow) 2 Horizontal stripe (indication of the state of phase), green = liquid // blue = gaseous cold // red = gaseous hot 3 Information field (label of the refrigerant) fig.12: Marking the direction of rotation of the compressor drive motor The direction of arrow indicates the direction of rotation of the compressor drive motor Marking the direction of rotation of the oil pump motor (information plate) fig.13: Marking the direction of rotation of the oil pump motor The direction of arrow indicates the direction of rotation of the oil pump motor 35

36 Description of Design and Function Labels of the pressure gauge (information plate) Labeling of the control / control cabinet (information plate) Label on the rear side of the control unit of the control system (visible after opening the switching cabinet): Project name Make number of the package/chiller MPI address Label on the inside of the switching cabinet: fig.14: 1 Test verification for the control system Labels of the pressure gauge Description of the pressure gauge measuring point The description of the pressure gauge measuring point is attached directly underneath the pressure gauge. The gauge board can be arranged horizontally as well as vertically. fig.15: 36 Test verification for the control system

37 7.5.9 Designation of the earth connection Description of Design and Function See general assembly drawing for the position of the earth connections. Safety labels The cross-section of the ground wire must be at least 10 mm². Alternatively, two separately installed and separately connected ground wire must be used, ensuring the minimum cross-section in the sum. fig.16: Designation of the earth connection Importance of the labels Ensure that the product is properly grounded before start-up. Connect the earth connection. The necessary mounting hardware and cables are not included in scope of supply. 7.6 fig.17: Process flow diagram Process flow diagram Grasso SP1, M-series 1 Suction side 2 Compressor 3 Oil separator 4 Pressure side 37

38 Description of Design and Function 7.7 Main components Screw compressor packages within the Grasso M-series series consist of the following main assemblies and components: The documentation of the main components is part of the product documentation (see product description or operating manuals of the supplier, e.g. for the compressor drive motor). fig.18: Main components of the GEA Grasso M-Series 10 Screw compressor See installation instructions for the screw compressor 15 Compressor drive motor See operating manual of the compressor drive motor 20 Oil separator See component documentation 25 OMC block (possible as separate oil filter for greater amounts of oil) See component documentation 30 * Oil cooler See component documentation 40 * Oil pump (possible as an external oil pump for booster) See component documentation 45 ** Suction filter See component documentation 55 ** Check valve - suction side See component documentation 60 Check valve - pressure side See component documentation 95 Coupling housing See component documentation 180 Controller See control unit documentation 360 * Oil heater See component documentation Safety devices See component documentation 38

39 Description of Design and Function * not shown in the picture ** integrated into the screw compressor Screw compressor fig.20: fig.19: Compressor drive motor GEA Grasso M-Series, arrangement of the compressor drive motor GEA Grasso M-Series, arrangement of the SCP The screw compressors are characterised by a compact design, high reliability, high quality components and ease of maintenance. Screw compressors are dual rotor positive displacement machines that run according to the displacement principle and operate by oil injection. Standard: The compressors are driven via a coupling by means of an air-cooled 2-pole IP23 electric motor with an operating voltage of 400 V; 50 Hz. Option: Other protection classes, operating voltages and frequencies as well as speed-controlled motors are available on request. Screw compressors are operated with refrigerant (standard: ammonia NH3, other refrigerants upon request). For the refrigerant, refrigerating machine oil is chosen in accordance with lubricating oil information for screw compressors. The documentation of the electric motor (operating manual) is an integral part of the product documentation. Various series and sizes of screw compressors are available for different fields of application. The screw compressors are driven directly by the compressor drive motor via a flexible coupling. The documentation of the screw compressor (installation instructions, part lists, drawings) is an integral product documentation. 39

40 Description of Design and Function Compressor with coupling housing fig.22: fig.21: GEA Grasso M-Series, arrangement of the coupling housing The coupling housing contains the coupling and is used for the attachment of the compressor drive motor. The elastic design of the coupling brings about the neutralisation of otherwise disturbing influences such as axial or radial forces, vibrations or offset. Oil separator GEA Grasso M-Series, arrangement of the oil separator The design of the oil separators is standardised and features reduced oil carry-over and low oil consumption. The oil separator is installed horizontally. The documentation of the oil separator (operating and maintenance instruction, acceptance certificate) is a integral part of the product documentation. Speed fluctuations and speed shocks are damped and cushioned, torsional vibrations are reduced. The documentation of the coupling is a part of the product documentation. Oil heater Electric oil heaters are built into the oil separator to heat the oil refrigerant mixture in the oil separator during the standstill of the screw compressor package. The oil heater prevents condensation of the refrigerant into the oil and, thus, any foaming of the oil during start-up. Oil heaters are equipped with: Temperature controller for protection against overheating (Switching temperature 110 C) Temperature limiter in case of faults, e.g. protection against dry running (permanently set to 150 C) The oil heater is switched on when the screw compressor package is stopped and is switched off automatically on starting. A manual switch-off for long standstill periods is recommended. 40

41 Description of Design and Function Oil cooler The documentation of the oil heater (operating and maintenance instruction, acceptance certificate) is a part of the product documentation OMC block with oil filter system fig.24: GEA Grasso M-Series, arrangement of the oil cooler The oil cooler is used for cooling the oil heated in the compressor in order to ensure sufficient oil viscosity for supplying to the compressor. fig.23: The documentation of the oil cooler (operating manual, acceptance certificate) is an integral part of the product documentation. GEA Grasso M-Series, arrangement of the OMC block with oil filter system The OMC block contains the oil distributor system in the oil circuit. Necessary control and shutoff fittings are integrated in the OMC-block. Connections for temperature and pressure sensors as well as service ports are present. The OMC block is combined with a standardised filter system and oil pump unit and forms the central control and regulation unit within the oil circuit Oil pump (optional) Special design for minor pressure differences (booster) Optionally, the OMC-block can be equipped with a 3way valve element (for ensuring a minimum oil temperature when starting the compressor). The documentation for the OMC block (operating manual, acceptance certificate) is an integral part of the product documentation. 41

42 Description of Design and Function fig.25: Suction filter - check valve combination GEA Grasso M-Series, arrangement of the (optional) oil pump The oil pump is an important component of the oil circuit. It is used for pumping and distributing refrigerating machine oil. The oil pump ensures that the oil is distributed to the individual lubrication points (e.g. journal bearing, balance piston and packing gland of the compressor). The documentation of the oil pump (operating manual, acceptance certificate) is an integral part of the product documentation. fig.26: GEA Grasso M-Series, suction filter - check valve combination The suction filter - check valve combination contributes substantially to the high working reliability of the components and the overall product. The suction filter - check valve combination prevents dirt particles carried by the suction flow from entering into the screw compressor. The documentation of suction filter check valve combination is an integral part of the compressor documentation. 42

43 7.7.9 Controller Description of Design and Function Non-volatile saving of program Possibility of communication with master controller via MPI (optionally via Profibus-DP, Modbus RTU or Modbus TCP) The documentation of the controller (operating manual, circuit diagram, parameter list, communication guideline) forms part of the product documentation fig.27: GEA Grasso M-Series, arrangement of the controller The screw compressor package is equipped with a GEA Omni -type controller. The GEA Omni consists of the control unit with operator keypad and display unit, indicator lights for "Running", "Warning" and "Alarm", the emergency stop button, the output relays and the casing. The GEA Omni is mounted directly on the package as standard. As an option, the GEA Omni can be installed in a control centre. The GEA Omni performs the following functions as standard: Display of all important physical and technical parameters, e.g. Pressure, temperature, motor current, capacity, number of operating hours, operating mode and status signals Automatic start up and shut down of the screw compressor package and capacity control dependent on the suction pressure or an external temperature, Monitoring of all operating parameters Compressor capacity limitation, in case the measured discharge pressure, suction pressure, secondary refrigerant temperature or motor current indicate overload Fittings The term fitting generally designates a control element of the machine. Among other things, the term fitting is also used for valves if these are used for the control and regulation of fluid flows in the piping. Furthermore, all kinds of installations in piping, such as sight glasses, measurement apertures, filters and similar are also designated as fittings. Therefore, fittings also include all kinds of valves, such as: Stop valves Check valves Safety valves Throttle valves Each fitting has its own field of use, according to the pressure or temperature in the pipe, the size of the pipe, the sealing requirements for the fitting, the reduction and direction of the flow of liquid as well as the medium itself. The safety fittings are used to limit the pressure in systems which are under pressure. Each fitting is designed for the specific application. The fittings can be operated manually or by motor,by gear motors, or pneumatic or hydraulic cylinders, for example. In reset fittings, the flow of fluid in the pipe causes automatic closing of the valve. Depending on the model, different closing elements (e.g.valve discs, flaps, pushers) close the pipe connected to the fitting. Fault memory with date and time Wire failure detection for all analogue input signals Password protection for preventing unauthorised access to important parameters The documentation of the fittings (acceptance certificates) forms part of the product documentation. 43

44 Description of Design and Function Safety devices Safety device to prevent the discharge temperature from being exceeded (resistance thermometer 120) The following safety devices are fitted onto the SCPs of the GEA Grasso M-series type series: The compressor control system switches off the screw compressor package when the specified limit value has been exceeded. Drive motor safety devices Rated current limitation (016) Limit value = see parameter list The rated current limitation is realised by the compressor control system: When the rated motor current is exceeded, the control slide of the compressor is driven in the MIN direction until the motor current reaches a permissible level. The normal output control then comes back into force. Safety device to prevent the oil temperature from being exceeded (resistance thermometer 125) The compressor control system switches off the screw compressor package when the specified limit value has been exceeded. Thermistor (017) Limit value = see parameter list The thermistor shuts down the compressor drive motor when the temperature of the compressor drive motor windings exceeds the allowable value. The minimum oil viscosity for safe compressor operation is 7 cst. In case of oils that are soluble in refrigerant, the minimum oil viscosity is to be ensured depending on the discharge pressure and temperature, oil temperature, as well as the type of oil. Pressure-controlled check valve integrated into the compressor (055) The check valve function prevents pressure equalisation with the LP side of the plant and simultaneous prevents a reverse rotation of the screw compressor. Overflow valve (340) The overflow valve protects the compressor against impermissible high pressure. The overflow valve (provided that delivered unassembled) must be connected with the suction pipe on site. Check valve - pressure side (060) The pressure side check valve prevents refrigerant from re-condensing in the oil separator. Triggering pressure = see parameter list and P+I flow chart Oil pressure regulating valve (075) The oil pressure control valve regulates the differential pressure between the oil pump discharge side and the discharge pressure of the package. The oil pressure control valve is integrated into the OMCblock (oil management centre). The overflow valve is designed in accordance with DIN EN "Refrigerating systems and heat pumps - pressure relief devices and associated piping - methods for calculation". Warning! Safety device to prevent the discharge pressure from being exceeded (pressure transducer 105) If not fitted on delivery, the overflow valve must be connected to the suction side when installing the SCP in the refrigeration plant! The compressor control system switches off the screw compressor package when the specified limit value has been exceeded. Safety valve (345) on the oil separator Limit value = see parameter list The safety valve protects the screw compressor package against impermissible high pressure. Safety device to prevent the differential pressure between the oil pressure after oil pump (pressure transducer 110) and the discharge pressure (pressure transducer 105) oil circuit monitoring from falling too low Triggering pressure = see parameter list and P+I flow chart The compressor control system switches off the screw compressor package when the pressure difference between oil pressure after oil pump and discharge pressure falls below the specified limit value after a delay period. If the screw compressor package is installed into a refrigeration system comprising an emergency blowoff station, only the oil separator connection is used. The valve is available as an option, depending on the required acceptance. Limit value = see parameter list 44

45 The safety valve is designed in accordance with DIN EN "Refrigerating systems and heat pumps pressure relief devices and associated piping - methods for calculation". Description of Design and Function Oil pressure after oil filter - optional - Differential pressure of oil pressure after oil filter and discharge pressure (oil filter monitoring) optional - Safety pressure limiter (350) Safety pressure limiter with two separate trigger contacts, one of which can only be reset using a tool. The safety pressure limiter switches off the compressor drive motor if the discharge pressure rises above the set point Warning! Switching off pressure 1 = see parameter list The components and parts the customer installs in particular the secondary refrigerant and cooling medium circuits as well as the oil circuit need to made from materials suitable for the fluids flowing through them. Furthermore, in the event of modifications to the product by the customer, the effects on the safety devices are to be checked. Switching off pressure 2 = see parameter list If it cannot be ruled out that the liquid refrigerant might attain more than 90% of the oil separator s volume, then the customer must install an additional safety valve to prevent expansion of the liquid in the oil separator (design in accordance with DIN EN 13136, arranged according to EN Annex F) Monitoring devices GEA Refrigeration Germany GmbH does not assume any liability for damage arising and the violation of the safety regulations which result from the use of unsuitable materials or through modification to the product which is not considered in the original safety concept. The following operating values will be continually monitored in a standard screw compressor package: Suction pressure Discharge pressure Oil pressure oil circuit monitoring Suction temperature Discharge temperature Oil temperature absolute primary slide position Motor current Suction pressure saturation temperature Saturation temperature of condensing pressure Number of running hours Difference between oil and discharge pressures (oil circuit monitoring) Set point of controled value in C Real point of controled value in C Internal volume ratio Used refrigerant Controled value Used options Components installed by the client 7.8 General functional description Screw compressor packages are refrigeration system components and serve to compress refrigerants such as ammonia (or other operating media on request). Operation as a heat pump is also possible. 7.9 Refrigerant circuit The screw compressor draws in refrigerant vapour via the suction check valve and suction filter and then discharges the compressed vapour into the plant via the oil separator and discharge check valve. The suction-side check valve prevents a sudden pressure equalisation with the low pressure side of the chiller, while also preventing reverse rotation of the screw compressor. The pressure side check valve prevents refrigerant from re-condensing in the oil separator. 45

46 Description of Design and Function not regulated. The maximum temperature of the heating rod is restricted. The discharge check valve can be integrated into the oil separator for screw compressor packages with discharge side nominal diameters up to NB Before it is returned to the compressor for use, the oil heated up in the compressor has to be cooled down to a temperature at which it has sufficient viscosity. The suction filter prevents dirt particles carried by the suction flow from penetrating into the compressor. The filter element is characterized by a very large filtering area. The filter fineness is 140 μm. Gas vibrations which can arise in the pressure chamber of compressors under high pressure conditions in the range of zero delivery are prevented by a gas vibration protection system. This comprises a pressure compensation line between the oil separator and the working chamber of the compressor Oil System The screw compressors operate oil-flooded. During the compression process, refrigerating machine oil is supplied to the compressor for lubrication, sealing, noise reduction, and absorption of part of the compression heat. After the compression process, the oil is separated again from the refrigerant in the oil separator Oil separation The refrigerant-oil mixture is led into the first part of oil separator. The first part of the oil separator consists of two chambers. The first chamber employs gravity separation. The hot gas passes the demister while flowing out of the first chamber into the second chamber. The oil separated thereby is collected in the second chamber. Both the chambers of the first part of oil separator simultaneously serve as oil receivers. In the second part of the oil separator, the fine separation of the aerosol oil portion from the refrigerant is performed by means of replaceable fine oil separation cartridges. The oil separated in the fine separation part of the oil separator is returned to the compressor via an additional orifice Oil heater The oil heater on the oil separator is to be started when the package is shut down in order to ensure a minimum oil temperature and sufficient oil viscosity required for restarting the package. The oil heating is 46 Oil cooling The following oil coolers are available: 1. liquid-cooled (non corrosive media) water (non corrosive) propylene glycol (25%) ethylene glycol (35%) Other refrigerants on request 2. Thermosiphon 3. Refrigerant injection Oil filter After cooling, the oil enters the oil filter which retains solid particles from the entire oil flow. Due to its large surface, the star-folded glass fibre element has a high absorbing capacity and thus a long operating lifetime. The filter has a relative filter fineness of 25 µm Oil pump The oil pump runs for pre- and during compressor operation. It draws the refrigeration compressor oil from the receiver space in the oil separator, through the the oil cooler and oil filter and pumps it to the bearings, the balance piston, the shaft seal, to the capacity control system and, if fitted, to the compressor's hydraulic Vi adjustment system. The oil pump pumps more oil than the compressor uses. This surplus quantity of oil is returned to pump suction via the spring loaded oil pressure regulating valve. The oil pressure regulating valve regulates a pressure difference between the oil pump discharge side and the unit final pressure (according to the value in the P+I diagram).

47 Oil injection Description of Design and Function The injection oil is fed without a pump via the oil injection regulating valve. Danger! The oil injection control valve is used to adjust the necessary compression discharge temperature. When operating the screw compressor package in explosive atmospheres, the special safety instructions for use in explosive atmospheres that are mentioned in this operating manual must be heeded. The control valve is provided with a check function to prevent sucking refrigerant through the oil pump Oil circuit, OMC block An OMC-block (oil management block) is flanged on to the oil filter as an oil distributor system. The oil flow is distributed via the bore-holes and channels to functional ranges of the screw compressor. All regulating valves and shut-off valves necessary for the regulation of the oil circuit are integrated into the block. As a result, a centralised control unit is available for the screw compressor package. The oil filter with OMC-block (oil management block) is fitted with an oil drain and refilling stop valve which may be connected to a separate oil pump or receiver. Designed for use in explosive atmospheres! The screw compressor packages can basically be used in explosive atmospheres. Some specifics must be heeded when using the screw compressor packages in explosive atmospheres of installation zones 1 and 2. The basis for use in explosive atmospheres is the following data of the operator: Zone division as per EN (or other equivalent international standards), Vent valves are fitted to oil filters for maintenance and repair purposes. description of the atmosphere (required gas groups), The oil in oil filter may be drained for changing oil filter via a separate stop valve. required temperature class Capacity control The screw compressors are fitted with a continuous capacity control with a range of %. The capacity is adjusted by shortening the screw compressor stroke. The defining factor for the compression process is the effective rotor length; this is altered by a hydraulically operated control slide. The position of the control slide is recorded by the position sensor. Upon reaching the MIN or MAX end position, it is signalled to the control device and the relative control slide position can be displayed in percentage on the touch panel. This data is stored in the request sheet for project A. The A request sheet is part of the product documentation. For using and placing a screw compressor package into operation within the EU, the package is manufactured ATEX-compliant (see component selection, protection systems, regulations, etc.) The following marginal parameters generally apply: The screw compressor packages can be installed in Zones 1 and 2 in accordance with EN The max. achievable temperature class is T4. The screw compressor packages are not suitable for carrying explosive mixtures; the suction pressure of the package is always in the overpressure range. The hydraulic adjustment of the control slide is realised using solenoid valves, which are integrated into a single block. The control slide travel speeds in the MIN and MAX directions should, to the extent possible, be the same during operation to ensure better compressor control Technical specifications 47

48 Description of Design and Function Basic terms Refrigerant Fluids that can absorb the heat of a system and dissipate it to a refrigerant (reversible process) and are used for the cooling of a system (industrial process) Heating agents Media (liquid or air), which transport and emit the heat absorbed in the secondary refrigerant. If water is used as the heat carrier, the terms warm water or cooling water are also used Operating media Refrigerant Refrigeration machine oils Caution! Materials circulating in a plant (liquid or gas), which by means of their change of state of the package withdraw heat from another medium (cooling or heating agent) or can dissipate heat to this medium. Secondary refrigerant In order to ensure an adequate loadbearing capacity of the sleeve bearings and to ensure the service life of the roller bearings, a minimum viscosity of 7cSt (=10-6 m²/s) upstream of the compressor is required. A suitable oil must be carefully selected in consideration of the operating conditions. The selection criteria and selection tables are summarised in the technical information document entitled "Lubricant oils for screw compressors". This technical information forms part of the product documentation. GEA Refrigeration Germany GmbH can provide assistance in the selection of a suitable refrigeration machine oil on request Secondary refrigerant Low corrosion water Permitted brine levels: see Grasso Design Program The technical order specification defines the refrigerant used. All components of the screw compressor package are designed for use with the defined refrigerant. For other secondary refrigerants, compatibility with the materials used must be ensured. The safety data sheet for the refrigerant used must be observed. The safety data sheet is part of the product documentation Operating limits The screw compressors can be operated under the most varied operating conditions within the given limits of application according to the requirements involved. The limits of application listed below for the screw compressors are based on the operational principle of the screw compressor and thermodynamic ratios and are based on practical operating conditions and design. The tabulated data apply for single, two-stage and heat pump operation. Depending on the compressor the manufacturer selected, the specific operating conditions limitations may occur within the parameters in the table.

49 Description of Design and Function Caution! For specific operations the selection and evaluation will take place within the manufacturer's compressor selection programme. To avoid "zero flow" in the compressor, which can damage the compressor, the minimum control slide position in the manufacturer's compressor selection programme must be adhered to. "Minimal control slide position <value> % accepted start." If the value entered is "> 0", then a limitation of the control slide path must be put in place in coordination with the manufacturer. The path limitation can be set created mechanically with a stop sleeve or by installing virtual controls (virtual stop sleeve) on the compressor. 28 bar Maximum permitted pressure p bar g. max. or 52 bar Pressure ratio p / p0 π - min. > 1.5 Pressure difference (p - p0) Δp bar min. > 0.8 Suction temperature t0 (compressor inlet) t0h C min. > - 60 Discharge temperature (compressor outlet) te C max. < 120 Compressor frame size H L M/N *) M/N *) 28 bar 52 bar 50 Hz Hz max. Nominal torque **) Nm max. permissible speed min min. permissible speed min max. Drive power (kw) *) For type M/N, the compressor drive shaft ends are different for 28 bar and 52 bar versions. **) When running the compressor, the maximum torque falls by 25% as opposed to electrical drives. All of the following requirements must be observed! 1. Compressors for a discharge pressure up to 52 bar (currently not available) are equipped with housings made of a material of higher strength and are fitted with special components. 49

50 Description of Design and Function 2. Minimum suction overheating in compressor inlet: "wet" operation is not possible. 3. For Δ p = p - p o 2.9 bar an external oil pump to be taken for compressor sizes H to N. 4. For π 8 gas vibration protection is required. 5. For CO 2 usage the use of a completely electrified oil pump for injection and function oil needs to be checked in all types of compressors depending on the operating conditions; 6. The discharge temperature t e must be 10 K above the condensing temperature (t e t c + 10 K). 7. Due to the solubility of refrigerant in the oil following applies: for Ammonia: t e t oil + 5 K; t e t oil + 10 K,when using a PAG oil (solubility of the refrigerant in the oil). For R22, R134a, R404A, R407C, R410A, R507, CO2, natural gas, carbohydrate molecules: t e t oil + 10 K, wherein solubility of the refrigerant in the oil. To determine the permitted difference between the discharge temperature (t e ) and oil intake temperature (t oil ) the set viscosity and the solubility diagram for the refrigerant-oil pair from the lubrication supplier need to be adhered to. 8. Ensure that the oil viscosity will be cst (= 10-6 m²/s) for the oil supply to bearings. Take into account the drop in viscosity due to refrigerant dissolved in the oil! 9. Limits for temperature differences will be considered in compressor selection programs. 10. The oil temperature at the compressor inlet must be at least 18 C, the oil must be preheated if necessary. 11. The rate of temperature change at compressor suction side should not exceed 0,1 K/s. 12. Rotation direction: view of compressor s driving shaft clockwise. 13. For individual cases outside the permitted speed coordination needs to made with the manufacturer. p p 0 Δp π t 0h t e t c t oil Notes: Maximum permitted pressure Suction pressure Pressure difference Pressure ratio Suction temperature (compressor inlet) Discharge temperature (compressor outlet) Condensing temperature oil inlet temperature into the compressor 1. During tests of a certain application case, all the conditions specified in the table must be considered and adhered to. 2. Should the given limits not be adhered to in individual cases, then the manufacturer needs to be contacted. 3. In addition to the application limits stated in the tables, the applicable operating conditions of the compressor type in question must also be considered (e. g. start-up regime, oil pressure, oil quantity etc.). 4. Depending on the refrigeration requirements, economiser operation takes place at a control slide position between 100% and approx. 70% control slide position. 5. When using R134a as a refrigerant and a evaporating temperature > 60 C consultation with the manufacturer must be made Water quality requirements, parameters All water bearing components from the manufacturer deliver an optimum performance and provide maximum protection from corrosion, provided you meet all of the limiting values recommended in VDI 3803 issue (Tab. B3) for non-corrosive water and adequate water conditioning. 50

51 Description of Design and Function Water quality requirements, parameters If you fail to adhere to the limiting values stated in VDI 3803, the manufacturer cannot provide any warranty for water carrying parts within its supplied components. Clarification as to whether or not it is possible to adhere to these limiting values with the respective water conditions should be agreed on with a specialist company during the planning and design phase. The limiting values as per VDI 3803, as required for the use of carbon steel components in non corrosive water systems, are listed below. Criterion Value Appearance Unit per ml Active biological components KBE < 10,000 Thickness factor EZ 2-4 The use of carbon steel and cast iron is required in the most of applications water conditioning with corrosion inhibitors. The use of stainless steel requires very special monitoring of water in apply to Chloride contents (risk of stress crack and pitting corrosion). Water quality requirements, parameters Criterion Value Recommend when using plate heat exchangers in the refrigerant circuit Unit < 100 ppm Cl while using steel and clear, without sediment maximum 40 C wall temperature in the plate heat exchanger Colour colourless < 200 ppm Cl while using steel and Odour none maximum 100 C wall temperature in the plate heat exchanger ph level at 20 C Electrical conductivity LF < 220 ms/m Ca2+, Mg2+ < 0.5 mol/m³ General hardness, for stabilization GH < 20 d Carbonate hardness without hardness stabilizer KH <4 d Chloride Cl Soil alkali Sulphur fig.28: SO4 < 150 < 325 g/m³ g/m³ Corrosion resistance in presence of chlorides X Chloride ion concentration in ppm Cl- Y Wall temperature heat exchanger in C A AISI 304 B AISI 316 C SMO

52 Description of Design and Function Manufacturer's recommendation: Use uncontaminated secondary refrigerants and cooling media, in particular in chillers and when using of plate heat exchangers. The media quality must be assured by means of an appropriate filter on the inlet to the heat exchanger. The mesh for such a filter must be 0.9 mm! Should the chiller be required to remain in operation during filter cleaning, double filters must be used. Pressure loss through the filter must be taken into consideration on the building side when configuring the pump. The manufacturer recommends enlisting the services of a reputable water conditioning company. 52

53 8 Start-up START-UP 8.1 Important information for start-up The following points must be observed before commencing with the start-up: Check of the external condition of the screw compressor package (check of insulation, transport damage... ). The area around the machine in which the startup is carried out must be marked and secured against the access of unauthorised persons. Sufficient lighting of the working area must be ensured to prevent personal injury and material damage. Personal protection gear (work clothing, work boots, gloves) must be worn during all work on the screw compressor package. There is a danger of impact and stumblingfrom protruding parts on the screw compressor package (e.g. valve caps). There is also the danger of cut wounds on sharp edges and rough surfaces. All activities must therefore be carried out with particular attention. Suitable hearing protection must be worn in order to protect against damage to hearing or deafness. Thermal hazards resulting in injuries due to burns or freezing may occur on contact with parts of the system which are at a very high or very low temperature. Personal protective equipment must be worn. Suitable tools or special tools must be used. Check that all electrical work has been carried out in accordance with the standards (e.g.protective earth, insulation, shielding, covers). If necessary, an earth connection must be provided. Pipes and pipe sections must be secured to ensure sufficient mechanical strength. The pipes and equipment of the screw compressor package must not be entered. Operating media (nitrogen, oil, refrigerant) can escape. Preventive measures must be taken to collect and dispose of them in an environmentally responsible manner (e.g.using an oil pan). Personal breathing protection must be kept ready in the event of a refrigerant leak. The safety data sheets of the oil and refrigerant used must be read prior to commencing start-up work. Familiarise yourself with the evacuation plan of the installation location. Warning! Contact with live components is prohibited. The Customer Service department of GEA Refrigeration Germany GmbH offer comprehensive support for starting up the screw compressor package. For contact details, please refer to the chapter entitled "Technical customer service". Warning! The screw compressor package must only be operated by suitably skilled personnel who are familiar with the contents of the operating manual for screw compressor packages. The safety regulations for refrigeration plants must always be observed in order to prevent damage to the screw compressor package and injury to the operating staff. The screw compressor packages are tested and accepted at the works. By the time these screw compressor packages are delivered to the customer, the following work will have been carried out: Complete installation of the cooling system and in particular: cleaning and drying the refrigerant and oil circuits Leak test with air Evacuation of the refrigerant circuit and filling with protective gas (nitrogen) to a pressure of 0.3 to 0.5 bar (above atmospheric) Electrical wiring and testing of the wiring Factory setting for the parameters on the control Factory setting of the safety and monitoring devices Works trial runs (at the request of the client) 53

54 Start-up Danger! Solid mounting of the coupling protection must be checked. Start-up must not be carried out with the coupling protection mounted. Check the protective gas filling (a positive pressure 0.2 bar must be present) If defects are found, notify GEA Refrigeration Germany GmbH Service and proceed according to their instructions. 8.2 Basics The compressor must only be switched on if the screw compressor package has been correctly connected and filled with operating materials. The activities described in this "Start-up" chapter must be carried out in the prescribed sequence. Check that components which have been removed for transport, separately delivered components and components provided by the customer are firmly attached. Check that all locating bolts are tight The nitrogen filling of the screw compressor package must be purged by opening the vent valves before the connection of the pipes. Establish all pipe connections so that the transmission of thermal expansion and vibration to the screw compressor package is limited as far as possible. Bellows-type expansion joints made of steel, or flexible metal hoses can be used for refrigerant and oil lines, bellows-type expansion joints made from rubber can be used for water connections. Provide all pipe connections directly at the unit with fixed points. The screw compressor package is operated via the terminal of the control unit. After the target values have been entered, both automatic and manual operation are possible. The software of the control device and operation via the terminal are described separately in the operating manual for the control system. 8.3 Connection of: Suction line Pressure line Oil cooler water connection If units are equipped with a safety valve: Connect safety valve to the blow-off line. Integrate relief valve in the suction line. if units are equipped with a refrigerant cooled oil cooler: Connecting the screw compressor package Connect the refrigerant feed line from h.p. receiver (note geodetic height above oil cooler). Connect the evaporated refrigerant line to the condenser Caution! All mechanical connections must be made according to the R+I diagram which is valid for the project. The R+I diagram is part of the product documentation. Caution! Connecting the pipes If refrigerant injection is used: Connect the refrigerant feed line from condenser or h.p. receiver If an economiser is used: Connection the suction line of the economiser to the charge connection. All electrical connections must be made according to the circuit diagram which is valid for the project. The circuit diagram is part of the product documentation. 54

55 Start-up Compressor control supply In principle, all the connections must be made in accordance with the P+I diagram applying to the respective project. Attach the pipes to the screw compressor package in such a way that no additional static or dynamic loads are imposed. Oil heater Oil pump Some external components, such as the second EMERGENCY STOP switch, the ammonia sensor and the fans of the machine room, must be connected by the system erector on site. All the pipes and systems to be connected must be checked for leaks when the work is complete Electrical connection Danger! Contact with live components is prohibited. Check that terminal screws (in the switching cabinet) are tight. 8.4 Paint and insulation Damage to the paint and insulation during transport and installation must be carefully repaired. The screw compressor package has been designed for plug-in and reliable automatic operation. 8.5 All connections must be carried out according to the current installation regulations. The following procedures should be completed in the sequence in which they are described: Connections to the screw compressor package must be flexible and free of loads Dimensioning of the inlet pipe crosssections must be according to DIN VDE 100 Part 520. Before starting work, make sure that all parts to be connected are de-energised, e.g. by removing the main fuse in all phases or installing a jumper wire. The insulation resistance of the electrical tools and fixtures and wiring is to be checked. The connection may only be undertaken if this value lies in the allowable range. Connections and almost all external connections are pre-wired at the factory. The electrical consumers and sensor must be connected according to the circuit diagram. All electrical connections must be made according to the circuit diagram, e.g. Checking the electrical connection Danger! Contact with live components is prohibited. Check that all electrical work has been carried out in accordance with the standards (e.g.protective earth, insulation, shielding, covers). If necessary, an earth connection must be provided Leak test Warning! Produce the earth connection according to the designation in the general assembly drawing. See chapter "Designation of the earth connection". Start-up procedure See type plate for permissible operating pressure. The necessary safety precautions should be taken before performing the leak test. An approx. 3-hour pressure drop test with dry nitrogen is used for the test. Test pressure: 7 bar A pressure drop of 2% is allowed during the 3 hours. Fluctuations in the ambient temperature must be taken into account. Compressor drive motor 55

56 Start-up Caution! Checking devices which could be damaged by the specified test pressure must be removed or blocked before the leak test is performed. A record should be kept of the pressure test, noting the pressure in the pipes tested, the ambient temperature and the outside temperature in the shade at hourly intervals. The removed measuring and control instruments should be reinstalled after completion of the leak test and if there are no leaks in the package/chiller. Test strategy fig.29: Dry nitrogen is used as the test medium. After reaching the test pressure, the pressure drop is measured via the differential pressure measurement. This may only change by 0.02 bar within an hour. If the display device does not indicate a leakage through foam formation, the system is sealed. Vacuum required to remove moisture from refrigerating plants X Room or Wall temperature in C Y Vacuum in mbar A Vacuum required to remove moisture from refrigerating plants Measured values have to be checked and recorded hourly after reaching the required vacuum. After the vacuum pressure, the temperatures in the machine house and the outdoor temperature in shade must be entered in the log. After the vacuum test, the pressure compensation must be carried out with NH3. Testing devices A pressure gauge with an accuracy of 0.5% over the entire measuring range, with a digital resolution of 0.01 bar must be used for the measurement. The testing described here is based on pressure gauges with pressure gauge and LEAK mode from Keller. Warning! Display devices Shut the oil pump during evacuation! A foaming agent must be used as the means to indicate leakages. A solution of 50 parts water and 1 part detergent can be used as the foaming agent. Leaks are detected through formation of foam. A leak detection spray can be used in problem areas. See also "Evacuation on refrigerant side" in the chapter "Maintenance work". Carrying out the test 1. Wet all connecting joints (welded seams, flange connections, screw fastenings, etc.) with foaming agent. Remedy any leaks detectable from the noticeable formation of foam Drying, vacuum After the leak tightness test has been completed, the plant must be evacuated and undergo a vacuum test for 3 hours. Evacuation is used to remove air and moisture from the plant. A vacuum pump must be used for evacuation. The permissible increase in vacuum is maximum 6.66 mbar over a period of 3 hours. 56

57 8.5.4 Start-up Operating position of valves For the positions of the manually controllable fittings for the operation of the package/chiller, see the P+I diagram. The layout and symbols used in the P+I diagram comply with the specifications of EN 1861, July 1998 Issue. Caution! The valves must be in operating position prior to the start-up of the package / chiller. Troublefree operation is only possible in this manner! Stop valve open during normal operation fig.30: Stop valve open Stop valve closed during normal operation fig.31: Stop valve closed Check valve during normal operation fig.32: Check valve Shuttable check valve open during normal operation fig.33: Shuttable check valve 57

58 Start-up Control valve adjusted: fig.34: Start-up when operating conditions change Control valve Shuttable check valve with integrated control function open during normal operation fig.35: Shuttable check valve with integrated control function Controlled by the controller (e.g. GEA Omni) fig.36: Solenoid valve Change-over valve (3-way valve), opened from below in arrow direction fig.37: Change-over valve Operating position: shut Δp x,x ± x bar control pressure to be set vis-à-vis reference pressure (see P+I diagram) fig.38: Oil pressure control valve Caution! An oil pressure being set too high or too low may result in serious compressor damage or even the total breakdown of the compressor after just a short period of operation! 58

59 Start-up Overflow valve, safety valve fig.39: Overflow valve, safety valve controlled self-sufficient fig.40: Pressure controlled check valve manually operated if necessary fig.41: Quick acting valve, spring-loaded ½ connections with cap fig.42: Charging valve, drain valve Connection Rp ¼ For pressure gauge and pressure transmitter fig.43: Service valve 59

60 Start-up controlled autonomously using control element fig.44: Oil temperature limiter Autonomous control via sensor fig.45: Temperature controlled control valve When charging with oil for the first time, oil must be charged via the service valve (135) too. To this end, the stop valve (065) must then be closed. Oil charge While operating the package, the oil level must be regularly checked (see chapter "Oil level check"). Caution! Check the oil grade to be charged! See contract/project or recommendation of GEA Refrigeration Germany GmbH. A comprehensive overview of the allowable oil types is provided in "Technical information on lubricating oils". This technical information is part of the product documentation. Caution! Due to the use of selected components, the refrigerating machine oils tend to absorb more moisture. Therefore, when charging a compressor the oil should be allowed to come into contact with air for a short time only. The contents of an opened drum have to be used up within one working day, provided the drum is properly closed between charging. For severely hygroscopic oils, the oil container must be placed under a protective atmosphere. The vacuum present in the screw compressor package before pressure compensation may be utilised for charging the package with oil. A separate oil charging pump is required after the pressure compensation and for refilling with oil The connection of the oil draining or oil charging stop valve (090) must be connected with the oil charging container. Pressure compensation with the cooling system Re-establish the vacuum. Carry out pressure compensation via the service stop valve (285). Before charging with oil, switch the valves to the operating position. The stop valve (090) must be opened until the oil level has reached a value between the upper edge of the sight glass indicator MIN (N10b, data sheet ) and lower edge of the sight glass indicator MAX (N10c, data sheet ) Checking the direction of rotation of the oil pump motor The oil pump is started with the driving motor electrically blocked (service). The stop valves are in the operating position. The oil separator is generally charged with oil via the oil cooler. 60

61 The direction of the arrow given for the oil pump must correspond to the direction of rotation of the oil pump motor. Caution! Since the slide ring shaft seal of the oil pump is dependent on the direction of rotation and can be damaged when this direction is wrong, checking must be reduced to a very short running period (less than 2 seconds). The adjusted differential pressure between the oil pump pressure side and the unit final pressure is checked with the oil pump rotating in the correct direction. It must not fall below the prescribed set value in the P+I diagram. Start-up 8. Check the excitation of the solenoid valves of the adjusting device for capacity control in the Minimum direction. 9. Simulate the minimum end position of the control slide and check the switching function of main switch and star-delta contactor (for motors with star-delta starting). 10. Checking the switching function of the solenoid valve by forcing the digital outputs. 11. Check the "Oil circuit monitoringfailure". only for external oil pumpafter 6s, the of the compressor drive motor must be shut off. To do so, the valve (70) must be throttled in such a manner that the alarm value for oil difference pressure as stated on the parameter list is ot reached. While the compressor is not running and the oil has not yet reached the operating temperature, the differential pressure can be slightly higher than the indicated value. 12. Set the motor current limitation acc. to nominal motor data. See parameter list! The differential pressure can be changed by rotating the spindle on the oil pressure control valve. (The differential pressure is increased by turning it inwards and vice versa) Checking the fault monitoring 1. Disconnect the incoming feeder of the compressor drive motor from the mains supply when checking the safety device (e.g. remove LV/HBC fuse links). Checking of the safety pressure limiter 1. Setting of the shut-off values as per the panel data report 2. Switch on the compressor package 3. Initiation of the shut-off value 4. Check the reaction: Compressor must shut off immediately Fault report on the display of the control unit 2. Apply voltage to the control device. 3. Check the built-in pressure transducer and resistance thermometer for correct wiring To do so, loosen the relevant contacts. The message "Broken wire <sensor XXX>" appears on the display of the control. Check that the display is correct after the contact has been re-established. Further information can be found in the controller manual. 4. Check limit values. Upon actuation, the emergency-off button must immediately shut off the compressor. 1. Actuation of the emergency-off button. 2. Check the reaction: Limit value = see parameter list 5. Switch on the screw compressor package/chiller from the controller. 6. "Oil circuit monitoring failure must be indicated after a starting delay time of 20 sec. Checking of the emergency-off button. Compressor must shut off immediately Fault report in the display of the control 3. Resetting of the emergency-off actuation to end the test. 7. Reconnect the oil pump motor to the mains supply. 61

62 Start-up Adjustment of oil pressure Danger! The oil pressure being set too high or too low may result in serious compressor damage or even total breakdown of the compressor after even a short period of operation! Before the compressor drive motor and therefore the unit can be started, the oil pressure must be set correctly by adjusting the oil pressure regulating valve (075). fig.46: For adjustment solely the oil pump must be started. For units with the control GEA Omni, digital output must be forced for this. The set value of the oil differential pressure should be taken from the P+I flow chart of the specific project. A Compressor B Motor The compressor drive motor is started directly and then switched off again by forcing the digital outputs. Oil differential pressure = oil pressure item (110) - discharge pressure item (105) Prior to the start-up of the compressor drive motor, the manufacturer's information, e.g. on the lubrication of the motor, must be followed at all costs. The differential pressure can be changed by rotating the spindle on the oil pressure regulating valve (the differential pressure is increased by turning it inwards and vice versa). To do so, the seal on the oil pressure control valve (075) must be removed. If the direction of rotation of the motor is incorrect, it should be corrected while the electric switchgear is secured to prevent the motor from being switched on accidentally. Then the motor must work for at least 1 hour, unencumbered and free from errors. This is important in order to dry out residual moisture in the motor (caused during transport or storage). The coupling protection must be in place during this start-up period as required by the labour safety regulations. After checking the direction of rotation of the drive motor, the coupling may be connected with the motor. In comparison to normal operation conditions, the oil differential pressure can be slightly higher if only the oil pump is operated or if the operating temperature is not reached yet (with the valve open to the same degree). In this case, the oil differential pressure should be readjusted (according to the value in the P+I flow chart) after start of the unit and reaching of the operation temperature Motor direction of rotation Checking the direction of rotation of the drive motor Warning! The coupling must not yet connect the motor and compressor! Mounting the coupling 1. The electric switchgear is secured to prevent it from being switched on accidentally. Secure the electric switchgear so as to prevent the compressor drive motor from being switched on accidentally. With the control slide in the MIN or MAX position, it should be possible to rotate the compressor shaft easily and smoothly by hand. When checking the direction of rotation of the compressor driving motor pay attention to the conditions for switching the compressor on. 2. Mount the coupling while observing the instructions of the separate documentation. 3. The values for radial and angular deviations given in the coupling documentation must be checked and corrected if necessary. The axis distance between the compressor drive motor and the compressor must be checked.

63 4. The real values have to record at data sheet of coupling documentation. Please send back a copy of the filled data sheet to: GEA Refrigeration Germany GmbH Holzhauser Straße 165 Start-up 4. The minimum end position (0%) must be reached and signalled when the "Decrease power" button is pressed. 5. Vent the adjusting device by moving the control slide backwards and forwards about ten times Berlin Fax: +49 (0) Caution! Observe the maintenance instruction! Caution! Regrease the coupling at the prescribed intervals if scheduled in the maintenance instruction for the coupling! Checking the water circuits Check whether the cooling and cold water pumps are running and the shut-off fittings in the cooling water circuit are in their operating positions. While the unit/ chiller is operating under project conditions, adjust the cooling water control so that the condensing and oil temperature lies within the permissible range Initial start-up Only adjustment times between 30 and 60 seconds are permissible. The throttle valves of the solenoid valves are adjusted in the factory in such a manner that they ensure an optimal adjustment time of the control slide of between 30 and 60 seconds. While running at operating temperature and pressure conditions, determine the adjustment times needed when the control slide is continually moved from the maximum end position to the minimum end position and back. For the automatic system to run smoothly, the adjustment times in either direction must be approximately the same. The adjustment time can be adjusted with the help of throttle valves DS5 and DS6. After carrying out the aforementioned works, the SCP can be commissioned in accordance with the operating manual of the control device. 1. Switch on the control voltage of the control device. 2. Remedy and acknowledge existing fault messages. 3. Select manual operating mode. Checking the control slide adjustment times See the assembly instructions for the screw compressor Checking the oil cooler Guide value for oil temperature = see parameter list 4. Turn on SCP. Oil cooling with water-cooled oil cooler The water volume must be regulated so that the cooling water volume corresponds to the project value. The inlet and outlet temperatures must be checked. The oil temperature adjusts automatically via the 3-way valve. Checking the adjustment of the control slide 1. SCP is running. 2. Select manual operating mode. 3. The maximum end position (100%) must be reached and signalled when the "Increase power" button is pressed. Checking the oil cooling with refrigerant-cooled oil cooler No regulating or checking required Adjusting the amount of injection oil and the oil temperature 63

64 Start-up Screw compressor packages without refrigerant injection The amount of injection oil and the oil temperature directly influence the discharge temperature of the compressor. The amount of injection oil is adjusted under operating conditions through the injection oil control valve. Standard values for discharge temperature t t max NH 3 /HP t t oil + 20K 30K 95 C NH 3 /LP t t oil approx C 80 C Freon/HD t t oil + 15K 80 C R22/LP t C 80 C Compressor units with refrigerant injection The oil temperature is changed by setting the injection oil control valve. The more the shut-off valve is throttled, the more the oil temperature decreases. If the oil temperature becomes too low or reaches the lower range, the setpoint for the discharge temperature should be set higher accordingly. In the first setting of the oil circuit, the control valve for injection oil is opened approximately half a turn. The discharge temperature is then regulated to the value indicated in the parameter list by means of the thermostatic expansion valve. 8.7 Restarting after approx. 1 year standstill Change the oil filter inserts (see maintenance instruction). Switch on the oil heater at least one hour before starting the screw compressor package/chiller. Open the stop valve on the suction side and the pressure side (or check valves which can be shut off). If fitted: Open the stop valves (or shuttable check valves) in the suction line of the economiser. If fitted: Open the refrigerant supply to the thermosyphon - oil cooler. If fitted: Open the manual stop valve of the refrigerant injection. Remove all non-condensable gases by venting. To this end, check the condensing pressure and temperature (see parameter list). Check the oil collection sump and drain if necessary. Switch on the compressor and observe the operating instructions of the electrical switchgear. Make a screw compressor package/chiller test run in order to test the sensor and actor technologies (for operation and indicating precision). Guide value for compressor end temperature: t e = C (for NH 3 ) Other refrigerants on request. 8.6 Start-up after long standstill periods 1. Inserting the main fuse 2. Switching on the control unit according to the operating manual. 3. Checking all parameters on the control unit display. See parameter list. 4. Checking the settings of all control and safety devices. 64

65 9 Use, operation, control USE, OPERATION, CONTROL Use in explosive atmospheres, installation zones 1 and 2 Danger! The same regulations apply to the operating instructions for screw compressor packages in potentially explosive atmospheres as described in the respective applicable operating manual. The screw compressor package must be only be operated by trained and qualified personnel who are familiar with the contents of the operating manual for GEA Refrigeration Germany GmbH screw compressor packages. The safety regulations for refrigeration plants must always be observed in order to prevent damage to the screw compressor package and injury to the operating staff. In addition to this, the following extensions apply: The screw compressor package is operated via the control panel of the control unit. If the control is included in the scope of delivery, the operating staff must be familiar with the contents of the complete documentation of the control unit. The documentation for the control unit is an integral part of the product documentation. 1. In addition, the legal safety regulations apply for the people responsible for operating the screw compressor package, and must be conformed with respect to the transport, assembly, operation and maintenance and if necessary the replacement of sub-assemblies, etc. in potentially explosive atmospheres. The operator directives must be complied with in this context see also section: Safety instructions for compressor, Appendix E and Screw compressor package, Appendix E. Both documents are an integral part of the documentation. 2. The relevant electrical engineering regulations for installations in potentially explosive atmospheres, especially EN , apply to the installation and connection of electrical components. Appropriate, prescribed cabling material must be used. 3. The entire screw compressor package must be earthed by the operator. Important information for the operator 9.3 Prerequisite for switching on The screw compressor package has been designed for automatic operation; the control unit controls the switching on and off of the compressor and its capacity adjustment. Continuous operation and observation of the screw compressor package is not necessary in automatic mode. The necessary steps for switching on the screw compressor package can be found in the controller documentation. If the screw compressor package is controlled manually, it must be operated from the refrigerator room. In particular, the repair and maintenance instructions must be complied with. The following prerequisites must be fulfilled for switching on the screw compressor package: 1. The main power must be available and switched on. 2. The screw compressor package must be sufficiently filled with refrigerant and oil. 3. The valves must be in the operating position. 4. The oil level in the oil separator must be within the permissible range. 65

66 Use, operation, control 5. The cooling and cold water pumps must be in operation. 6. The supply of cooling water or coolant to the oil cooler must be ensured. 7. The oil heater in the oil separator must have heated the oil sufficiently. The oil heater in the oil separator can be switched on while the screw compressor package is not running. It is then automatically switched off when the screw compressor package is started and switched on when it is shut down. If the ambient temperature is below 5 C, the oil heater must be switched on at least one hour before the screw compressor package is started. 8. The rated current limitation has been set according to the motor rating. The screw compressor package can be switched on as per the controller operating manual. 66

67 Use, operation, control Overview of the operating modes Modes Signal for Name Remark Start/Stop Capacity +/- 0 Service Oil pump by itself Compressor motor blocked 1 Manual + Manual Manual control via Touch Panel (TP) Manual Manual 2 Manual + Auto Manual Start/Stop via TP and full automatic local capacity control Manual Auto 3 Auto + Auto Full automatic start/stop and local capacity control Auto Auto 4 Remote + HW (cont) Start/stop and capacity demand via digital contacts (hardware) from a remote master controller. The GSC TP derives from the continuous +/- signals the pulses for capacity (indirect). External External continuous 5 Remote + HW (pulse) Start/stop and capacity demand via digital contacts (hardware) from a remote master controller. The master also generates the +/- signals as pulses for controlling the slide capacity directly. External External pulses 6 Remote + HW (loc. SW) Start/Stop from a remote master controller via digital contacts (hardware). The GSC TP controls the output depending on a local setpoint (TP) and from this setpoint also automatically switches the product ON/OFF. External + setpoint deviation Local Setpoint 7 Remote + HW (ext. SW) Start/Stop from a remote master controller via digital contacts (hardware). The GSC TP controls the output depending on an external setpoint (analog input) and from this setpoint also automatically switches the product ON/OFF. External + setpoint deviation Remote Setpoint 8 Remote + Net (cont) Start/stop and capacity demand via network from a remote master controller. The GSC TP derives from the continuous +/- signals the pulses for controlling the capacity (indirect). Network Network continuous 9 Remote + Net (pulse) Start/stop and capacity demand via network from a remote master controller. The master also generates the +/- signals as pulses for controlling the capacity directly. Network Network pulses 67

68 Use, operation, control Modes Signal for 10 Remote + Bus (loc. SW) Start/stop from a central master controller via a bus signal. The GSC TP controls the output depending on a local setpoint (TP) and from this setpoint also automatically switches the product ON/OFF. Network + setpoint deviation Local Setpoint 11 Remote + Bus (net. SW) Start/stop from a central master controller via a bus signal. The GSC TP controls the output depending on an external setpoint sent externally via the network and from this setpoint also automatically switches the product ON/OFF. Network + setpoint deviation Network Setpoint 68

69 9.3.2 Setting of setpoint and limiting values as well as safety devices Caution! The correct setting of all setpoint and limiting values is a prerequisite for the safe operation of the SCP. Use, operation, control GEA Omni performs the following functions as standard: Display of all important physical and technical parameters, e.g. pressure, temperature, motor current, capacity, number of operating hours, operating mode and status signals automatic start up and shut down of the compressor package and capacity control dependent on the relevant parameter for the application (e.g. the suction pressure or an external temperature), Monitoring of all operating parameters, Compressor capacity limitation if the measured discharge pressure, suction pressure, secondary refrigerant temperature or motor current indicate an overload, Fault memory with date and time, Wire failure detection for all analogue input signals Password protection for preventing unauthorised access to important parameters Non-volatile saving of programme, MPI communication with a master controller (optionally via Profibus-DP, Modbus RTU or Modbus TCP). For the setting of the setpoint and limiting values, the 1. details (steps) in the control operating manual and 2. the project-related data are instrumental. The program-based setpoint and limiting values as well as the setting values of the safety device are stated in the project-based parameter list. The parameter list forms part of the documentation for the controller. 9.4 Operation of the screw compressor package Caution! Read the control documentation carefully. Contact the GEA Refrigeration Germany GmbH technical customer service if you require assistance. The screw compressor package is operated using the control (standard: GEA Omni). The GEA Omni is mounted directly on the screw compressor package as standard, but can also be arranged in a control centre. The GEA Omni consists of the control unit with operator keypad and display unit (TouchPanel), indicator lights for "Running", "Warning" and "Alarm", the emergency stop button, the output relays and the casing. 9.5 Instructions regarding failures, their causes and remedies The screw compressor packages/ chillers manufactured by GEA Refrigeration Germany GmbH are highly advanced, automatic and extremely efficient systems. Nevertheless, faults can occur and may complicate any continuous operation of the plant or cause a failure of a part or the entire plant. All switching, operating and control actions are carried out via this TouchPanel. The TouchPanel is the interface between the man and the machine. 69

70 Use, operation, control Table of malfunctions Fault Cause Remedy The suction pressure is too low, performance is reduced and the system overheats. The suction pressure increases, the compressor(s) frost up to impermissibly high level or make noises that suggests fluid (refrigerant) in the compressor. The condensation pressure is too high. The compressor(s) will not start-up after switching on or it shuts down immediately after starting again. The compressors do not adapt to the required capacity. The compressors are shut off very often by the maximum pressure governor. The compressors are shut off very often by the minimum pressure governor. Slow loss of refrigerant through leaks in the refrigerant circuit. Pressure sensor defective. Defective capacity control devices in the compressors Suction filters are clogged The compressor/s are sucking in wet steam or liquid when started up. The safety device to prevent a too-high liquid level is not responding. There is air or other non-condensable gases in the refrigerant circuit. The electrical circuit is interrupted by a unit in the safety chain. No oil pressure is building up in the package/chiller. The oil circuit is disturbed by clogged oil filters or leaks. The capacity control device is malfunctioning due to disturbances in the oil circuit or mechanical influences. The condensation pressure is too high. The maximum pressure governor is defective or set wrongly. The suction pressure is too low. Check the entire system for leaks. Eliminate leakage, replenish refrigerant if necessary. Replace pressure sensor. Check capacity control devices, especially connections of solenoid valves Clean or replace the filter insert. Check the filling of the system, drain any refrigerant, repair safety device. Check for superheating. Vent the refrigerant circuit. Turn on the power, check safety devices and replace or correctly adjust if necessary. Exchange or clean oil filter elements, eliminate leaks and replenish oil. Check the oil circuit. The compressors should only be repaired by experts. Check the position detector of the compressor control slide. See above. Remove the maximum pressure governor, repair it, set it correctly or replace it. Open all valves on the suction side of the compressors. 70

71 Use, operation, control Table of malfunctions Fault Cause Remedy When operting, the package/chiller is louder than permitted. The pressure governor is defective or set wrongly. The heat transfer capacity of the evaporator decreases. The compressor(s) or the drive motor(s) is/are defective. Remove the minimum pressure governor, repair it, set it correctly or replace it. Check the evaporator for elevated oil concentration, drain oil if necessary. Inform the GEA Refrigeration Germany GmbH customer service 71

72 Cleaning, maintenance, repair 10 CLEANING, MAINTENANCE, REPAIR 10.1 The obligation for signage to prevent the unintentional switch-on of the plant during cleaning, maintenance and repair must be observed. Heed all safety instructions in this manual. Familiarise yourself with the local conditions of the screw compressor package installation site. Adhere to all legal and local regulations of health, work and fire protection as well as the regulations which must be heeded concerning the gases to be compressed. Use in explosive atmospheres, installation zones 1 and 2 Danger! Please read this manual carefully and completely prior to working on the screw compressor package. The same regulations apply to the maintenance instructions for SCPs in potentially explosive atmospheres as described in the respective applicable operating manual. Familiarise yourself with the special features of the screw compressor package. In addition to this, the following extensions apply: 1. In addition, for the persons responsible for maintaining the SCP, the legal safety regulations concerning the installation of the SCP in potentially explosive atmospheres with respect to the maintenance of the individual components or subassemblies or their complete replacement apply. 2. The maintenance may only be carried out in agreement / with the knowledge and release of the operator. 3. The maintenance and replacement regulations resulting from the operating manual for the components are to be complied with. 4. Appropriate special tools approved for the potentially explosive atmosphere must be used. 5. Only original spare parts may be used. Otherwise, any claim of warranty is void or, in case of damage, the operator is liable for this. 6. Each maintenance inspection (see maintenance book) must also include the checking of the secure fit of the threaded connections for the coupling safety hood Important information for service personnel Caution! There is an increased danger of slipping due to contact of operating media with the floor! The screw compressor package must be serviced by appropriately trained operating staff only. For all maintenance work, the maintenance instructions must be complied with. A maintenance checklist is part of the product documentation. The maintenance certificates in the maintenance checklist are completed and signed as part of the inspection and maintenance by authorised fitters as evidence of the work done. During the guarantee period, these confirmed maintenance certificates are a prerequisite for any claims under the guarantee. The responsible certified specialist company must be informed if any repairs are required. All maintenance and service tasks have to be carried out with care to preserve the functionality of the screw compressor package. Guarantee claims will not be valid if the customer failed to follow the maintenance instructions Cleaning the heat exchanger The following chapter is primarily aimed at the maintenance and service personnel of the screw compressor package. 72

73 Mechanical cleaning Mechanical cleaning is a maintenance measure in order to ensure the continuous safe operation of the screw compressor package. Components of the screw compressor packages (e.g.suction filter) can be removed for manual mechanical cleaning. Proceed in accordance with the details in the applicable component documentation. After completing cleaning work, properly mount the component and check for leakage Chemical cleaning Chemical cleaning of the screw compressor package is not recommended by GEA Refrigeration Germany GmbH Cleaning, maintenance, repair During cleaning, repair or maintenance work, the screw compressor package or its components must be protected against the penetration of moisture in order to prevent impairment of the function of the components. The chief principle must be to keep air and moisture entering the screw compressor package to an absolute minimum. All foreign substances must kept as far away as possible or eliminatedincluding welding residues, sealing remnants, auxiliary materials such as grease, oil or solvents. Welding and soldering work may only be performed with written permission. The requisite protective measures must be defined. These include: personal protective measures when opening the respective part of the system, complete draining of the respective part of equipment, cleaning with the appropriate cleaning agents, Danger! concentration measurements, Contact with live components is prohibited. ensuring sufficient ventilation and venting, performance of all welding work with the use of forming gas. Maintenance General instructions Maintenance work on the running screw compressor package is not permitted. If gas filled pipes are opened for maintenance work, these pipes must be in a gas-free condition. Work involving intervention in the refrigerant circuit must only be carried out by qualified engineers in accordance with the guarantee conditions. The screw compressor package must always be switched off before being dismantled. Before beginning the work, it must be ensured that all parts subject to maintenance/servicing are de-energised(e.g. by removing the main fuse or installing a shorting bridge). The refrigerant must be removed from the applicable parts of the system parts. This work must be carried out with great care, taking into account the safety regulations, so that the maintenance personnel are not injured by the refrigerant or by the refrigeration unit oil present in the system. Parts of the system under pressure must be completely vented before opening. While carrying out the repair, it is must always be ensured that a complete pressure balance of the affected pressure chambers with the environment is preserved. 73

74 Cleaning, maintenance, repair Repair work Modifications and repair work may only be carried out by qualified persons or persons with suitable training with the manufacturer's consent and must strictly comply with the rules set out in the maintenance instruction for the components concerned. New inspection and approval is required after pressure vessels that are subject to approval have been repaired or changed. Welding may only be carried out by approved welders with a valid welder s card Caution! The following maintenance notes must be observed: Only spare parts made by the original component manufacturer may be used for repairs and for replacing wearing parts. These are available from the spare parts department Repair information Important features of the technology and production process must be taken into account when repairing the plant: complete sealing of all devices and pipes. Dryness and cleanliness of the entire plant. Use of welding methods causing only a minimum amount of dirt to collect in the plant. Pipes bent on a pipe-bending machine only using refrigerating oil. If repairing the piping system from your own stocks, we recommend that you use a pipe with NBK surface quality (annealed and descaled, mechanically or chemically descaled after annealing). When carrying out repairs to piping systems, care should be taken to maintain the original piping routes. Only pipes of sufficient material quality, which are certified according to DIN should be used Repairs of pressure vessels subject to approval inspection The responsible monitoring body (e.g.tüv) must be notified in advance. 74 Maintenance intervals The maintenance intervals in accordance with the maintenance schedule must be observed. The maintenance schedule is an integral part of the product documentation. The maintenance schedule contains all the maintenance instructions and certifications for the first 15 years of performance of the screw compressor package. The maintenance certificates are completed and signed as well as acknowledged on the display of the control as part of the inspection and maintenance by authorised fitters as evidence of the work done. During the warranty period, these validated maintenance certificates also serve as a precondition for any warranty claim put to GEA Refrigeration Germany GmbH Maintenance work The documentation for the main components is a part of the product documentation. This contains important information to be considered before beginning the maintenance work Maintenance of the screw compressor Maintenance works are to be periodically carried out on the screw compressor (see maintenance schedule). These include: Measure axial play of bearings, Check shaft seal, Check primary slide movement, Check the adjustment of the position sensor.

75 The maintenance works on the screw compressor are described in the installation manual of the compressor. After 50,000 operating hours or in the 15th operating year, a general check of the screw compressor is planned by the manufacturer. Contact Customer Service in this regard Changing the block mounting filter element When must the filter element be replaced or cleaned? The oil filter element must be replaced as specified in the maintenance checklist for the total product from GEA Refrigeration Germany GmbH. Loss in pressure during operation is monitored by the internal control including a preliminary alarm function for preventative replacement. Cleaning, maintenance, repair 6. Check that the type designation/manufacturer ID number on the replacement element matches the type designation/id number on the filter s rating plate. 7. Place the replaced or cleaned filter element back on the mounting pin by turning it slightly. 8. Reposition the filter cover and tighten the four cover screws. Ensure that installation occurs without mechanical tension. 9. Vent the housing of the block mounting filter Switch the unit/ chiller off. 2. If the oil filter is very dirty, it may be necessary to replace it outside the normal maintenance schedule. 3. To change the oil filter insert, close the following valves in accordance with the P+I diagram and the oil filter documentation: The following applies as a guide value for replacement: The filter element should be replaced after every 5000 operating hours or once each year. Stop valve in front of oil filter (item 65) further stop valves in front of oil filter (if available), e.g. (item 220) if a thermostatic 3-way valve (item 215) will be used see P&I diagram Changing the filter element 1. Shut down the screw compressor package/chiller and depressurise the blocked mounting filter on the pressure side. Stop valve function oil (item 70) for Grasso SP1 or (item 190) for Grasso SPduo Control valve - injection oil with integrated check valve function (item 80) Do not forget to note the number of valve rotations when you close the valve (item 080). When opening the valve it must be returned to its initial position (see point 10). This is necessary to ensure the final temperature remains unchanged and therefore to avoid possible vibrations in the oil line. 2. Remove the filter cover by loosening the four cover screws. 3. Remove the filter element by slightly turning the mounting pin in the filter head. 4. Check the O-ring and support ring in the filter bowl for damage and correct positioning. Replace parts if required. 5. Replace glass fibre element, clean or replace wire mesh. The efficiency of the cleaning depends on the type of dirt and the level of differential pressure before replacing the filter element. If, after replacing the filter element, the differential pressure is more than 50% of the value before replacing the filter element, wire mesh must also be replaced. Replacing the oil filter Stop valve bypass oil cooler (optional) 4. Establish pressure compensation with the atmospheric pressure. 5. Drain oil. 6. Remove the cover of the oil filter. 7. Remove the oil filter element and properly dispose of it if it is highly soiled. 8. Carefully insert a new oil filter element. 9. Close the cover of the oil filter. 75

76 Cleaning, maintenance, repair 10. Reopen valves in accordance with item 3. The valve (80) must be returned to its initial position. 11. After the pressure has been compensated, vent the oil filter via the vent valve Cleaning the filter element The metal-gauze element used in the filter can be cleaned and reused several times before it has to be changed. Manual cleaning Maintenance of the suction filter Changing the filter element Immerse the soiled metal-gauze element in a clean, grease-dissolving liquid, then blow it through with compressed air from the outside inwards. Here it is important to place a cylindrical part possibly wrapped in corrugated cardboard inside the element to catch the dirt particles. The maintenance interval for changing or cleaning the filter element is specified by the manufacturer of the refrigeration system. Caution! The contamination level and mechanical condition of the filter element must be inspected at least once a year. Never use wire brushes for cleaning. To avoid fatigue failures of the metal gauze, strainer elements should be replaced with new, original filter elements after being cleaned 4 5 times. Before opening the filter, always make sure the filter housing is not under pressure. Caution! Refrigerant may leak out on opening the filter. The safety data sheets for the refrigerants in question must be consulted and any prescribed protective measures observed Oil draining, oil filling, oil change To remove the element, proceed as follows: Unscrew the cover. Aged oil demonstrates an increasing loss of ability to lubricate. Because of this, all rotating components of the compressor are endangered. The filter elements become prematurely clogged and must be cleaned and replaced at shorter intervals. 2. Pull out the cover with the filter element. 3. Remove the spring wire clamp. 4. Twist the element away from the cover to release the bayonet catch. 5. Detach the element from the cover. 6. Allow the element to drain off into a suitable container. Caution! When carrying out maintenance, always inspect the sealing ring (Oring) of the cover for mechanical damage and replace it if necessary. 7. Reassemble all parts with the new or cleaned filter element following the same procedure in reverse order. 76 Importance of oil change The oil in the screw compressor package/chiller must be changed: when the operating time of the oil charge has reached the technically specified oil change interval, Warning! Oil change intervals Oil change with ammonia as the refrigerant after every 5,000operating hours or after 1 year at the latest. Oil change with freon as the refrigerant after 10,000operating hours or after 2 years at the latest.

77 The assessment of the condition of the refrigerating machine oil by means of a general visual inspection (contamination) or laboratory analysis must be carried out: after 5000 operating hours: or at the end of one year's operation or after remedying major damage. or sure between the screw compressor package/ chiller and suction line. If screw compressor packages operated in parallel or other separate chillers are present, the refrigerant should preferably be drawn off at a pressure which is approx. 1 to3 bar above atmospheric pressure. Then re-close the stop valves bypass and the suction-side stop valve. Otherwise the pressure can be reduced by opening the vent valve on the suction filter and then disposing of the refrigerant as specified by law. if the oil becomes unacceptably contaminateddue to a major accident (e.g. water penetration into the refrigerant circuit). The degree to which oil in refrigeration plants has aged must be checked by analysis and in comparison of the data with those of fresh oil. Oil ageing can also be judged from the darkening of the oil colour and the deposits found in the oil filters. If the degree of ageing cannot be assessed reliably by laboratory analysis and the results of visual examination, it is advisable to change the oil at the following intervals (see maintenance checklist). Cleaning, maintenance, repair if the oil is dark coloured or very cloudy Oil change, maintenance work Take oil samples for analysis and comparison with the fresh oil data at regular intervals. Check the colouration of the oil visually and assess the degree of contamination. Depending on the results, the user must decide whether to approve the postponement of filling the oil until the next assessment date or whether to have the oil changed. Inadmissibly damp oil must be removed from the compressor unit/chiller immediately Changing the oil 1. The screw compressor package/chiller must be run for at least half an hour to reach its operating temperature before the oil can be changed. 2. First shut down the screw compressor package/ chiller as described in the operating instructions. 4. Then drain the used oil through the oil draining/oil charging valves and dispose of it (Caution! hazardous waste!). Once this has been done, re-close the valve and if possible continue to draw off the refrigerant with a compressor connected in parallel or a disposal device until atmospheric pressure is almost reached. 5. Otherwise depressurise the screw compressor package/chiller by opening the vent valve on the suction filter, taking into account the safety rules for refrigeration systems. 6. Open the drain plugs and valves on the oil cooler, oil separator and OMC block to drain any residual oil. Then re-close the drain plugs and valves. 7. Replace the filter element of the oil filter; replace and/or clean the filter element of the suction filter combination. 8. Evacuate the screw compressor package/chiller using a vacuum pump. Warning! Shut off the oil pump! 9. Pressurise the screw compressor package/chiller with a slight overpressure via the stop valve bypass check valve on the pressure side. 10. Then check all components for leakages. On successful completion, perform a complete pressure compensation with the discharge line followed by a repeated leakage test of the screw compressor package/chiller. The oil charge oil and start-up of the screw compressor package/ chiller must be accomplished in accordance with the operating instructions. 3. Open the stop valve in the bypass line around the check valve on the suction side and the stop valve on the suction side to equalise the pres- 77

78 Cleaning, maintenance, repair Used oil Refrigeration machine oil drained from the circuit is no longer suitable for use in refrigeration plants. It has to be stored or transported in appropriately labelled containers in accordance with the legal provisions. The operator is responsible for its proper disposal See chapter entitled "Start-up, charging with oil". For permissible types of oil, please refer to the technical information entitled "Lubricating oils". Oil removed from the compressor must not be re-used. Always use fresh oil from sealed containers! Do not mix with other types of oil. Draining the oil It may be necessary to drain the oil: Charging with oil, topping up with oil to inspect or repair the compressor and if there is too much oil in the circuit. The oil must be drained in accordance with points 1 to 6 of the chapter entitled "Carrying out oil change". The oil must be drained through the filling hose and into a container suitable for waste oil Check the oil level Oil pump maintenance Assuming correct installation in accordance with the conditions of use and correct fitting, gear pumps have the design prerequisites for long and fault-free operation. The gear pumps require a minimum of maintenance which is, however, indispensable for fault-free operation since experience has shown that a high percentage of the faults and damage which occur are attributable to the ingress of dirt and inadequate maintenance. The maintenance intervals have been defined in the maintenance checklist (part of the product documentation). An oil leakage of up to one drop/minute is required for the lubrication of the shaft seal and is permissible. The shaft seal is maintenance-free. If the oil leakage is too great, replace it according to the oil pump documentation. fig.47: 1 Sight glass - MAX (operation) 2 Sight glass - MIN (standstill) The oil level is checked visually via the sight glasses of the oil separator. The oil level should have a value between 1/2 filling level of sight glass N10c (MAX operation) and 1/2 height of sight glass N10b (MIN standstill). If the oil level is too low, i.e. the oil level has a value less than 1/2 filling level of sight glass N10b (MIN standstill), oil must be replenished. 78 Arrangement of MIN / MAX sight glasses The regular examination of all operating data, such as pressure, temperature, power consumption, degree of filter fouling, etc., helps in the early detection of potential failure! Changing the fine oil separation cartridges The fine oil separation cartridges should be replaced no later than after 25,000 run hours or 5 years.

79 If the oil carry over of the screw compressor package increases severely (oil recharging at unusually short intervals), replacement may be necessary even earlier. Cleaning, maintenance, repair Tightening screw fastenings Screw fastenings of components can become loose due to vibration or movement. Screw fastenings must therefore be checked regularly to ensure they are tight and retightened if necessary. Screw fastenings must only be tightened to the maximum tightening torques. Unless otherwise stated by warning signs, the tightening torque is dependent on the size and strength of the screw fastening. fig.48: Operating position of the fine oil separation cartridges 1 Cartridge(s) 2 Fixing cover with O-ring 3 Hexagon-head screw 4 Self-locking hexagon nut 1. Close the pressure and suction side shut-off fittings. 2. Drain refrigerant. Evacuate screw compressor package. 3. Check the pressure on the display of the control unit or by connecting a test pressure gauge. 4. Dismantle the pipe bend after the oil separator. 5. Dismantle the check valve installed in the oil separator. This step is omitted if a check valve which can be shut off is used on the pressure side. 6. Remove the self-locking hexagon nut [4]. 7. Loosen the hexagon-head screw [3] and the fixing cover with O-ring [2] for fixing the fine oil separation cartridges. 8. Remove the cartridge(s) [1]. 9. Mount the new cartridge. The cartridge must be inserted into the oil separator with the O-ring first. Assembly by carrying out steps 1-7 in reverse order. Warning! It is essential to apply self-locking hexagon nut [4] again and secure it against turning backwards! max. Tightening torque = 15 Nm Coupling maintenance 1. Switch the screw compressor package/ chiller off. 2. Secure the electric motor against accidentally being switched on. 3. Visually inspect the disk packs. 4. Check the tightening torques of the fit screws. 5. Check the alignment of the electric motor and correct it according to the steel lamination coupling documentation, if required. 6. Re-grease the coupling (if provided for in the maintenance instructions for the coupling) Checking the function of check valves In order for a check valve to be effective, it is important to perform function checks at regular intervals. An inspection is carried out by checking the noise behaviour of the valves during operation. After switching off the screw compressor package, malfunction on the suction side is indicated by prolonged turning back of the compressor. Malfunction on the pressure side leads to an increase of the standstill pressure in the package to the pressure level of the system pressure side Searching for leaks on the refrigerant side / leak test The absence of leaks is a precondition for perfect functioning of the compressor unit/chiller unit. Leaking parts or connecting elements will lead to the loss of refrigerant and oil as well as the penetration of air and moisture into the low pressure side. The site of 79