Signal exchange for aseptic filling machines - Minimum requirements for safe operation

Transcription

1 VDMA-Documents Food Processing Machinery and Packaging Machinery Signal exchange for aseptic filling machines - Minimum requirements for safe operation 2002/ No. 5 May 2002 (English edition: May 2003) Verband Deutscher Maschinenund Anlagenbau e.v. (Association of German Machinery and Plant Constructors) Fachverband Nahrungsmittelmaschinen und Verpackungsmaschinen (Industry Association for Food Processing Machines and Packaging Machines) Chairman: Ernst H. Berndl Managing Director: Richard Clemens Lyoner Straße 18 D Frankfurt am Main Tel.: Fax: nuv@vdma.org Internet VDMA Representing the capital goods industry

2 Contents 1 INTRODUCTION STANDARD CONFIGURATION: THE PROCESS SIDE CONTROLS DELIVERY NODES BETWEEN PRODUCT LINE AND FILLING MACHINE SCHEMATIC ILLUSTRATION OF THE STANDARD INSTALLATION CONFIGURATION IN AN ASEPTIC FILLING SYSTEM DESCRIPTION OF SIGNALS EXAMPLES OF SIGNAL EXCHANGE OPTIONAL CONFIGURATION: FILLING MACHINE CONTROLS PRODUCT DELIVERY NODES SCHEMATIC ILLUSTRATION OF THE OPTIONAL INSTALLATION CONFIGURATION IN AN ASEPTIC FILLING SYSTEM DESCRIPTION OF SIGNALS EXAMPLES OF SIGNAL EXCHANGE SIGNAL EXCHANGE BETWEEN FILLING MACHINE AND CIP CASE 1: CONTROL OF CLEANING SEQUENCE BY CIP CASE 2: CONTROL OF CLEANING SEQUENCE BY FILLING MACHINE This publication was drawn up by the Working Party for Interface Problems in Aseptic Plants in the Packaging Machines Division of the VDMA. It is available as a downloadable file from Suggestions for improvements and additions may be sent to the following address: Industry Association for Food Processing Machines and Packaging Machines in the VDMA, Lyoner Straße 18, Frankfurt am Main; Fax: Special thanks are due to Messrs. Rainer Ammann, Reinhard Kupfer, Michael Luippold and Ulrich Steinhauser who provided the basis for this working paper / gz/ FS_05_2002_English.doc Industry Association for Food Processing Machines and Packaging Machines, Page 2/11

3 1 Introduction Faults in the exchange of signals between the individual subsystems of an aseptic plant are a possible cause of incidences of unsterility. This potential for faults can be counteracted by the unique determination of the subsystem boundaries and a clear definition of the signals to be exchanged between the subsystems. The standard configuration presented here for the aseptic filling machine 11 subsystem takes these requirements into consideration and allows reliable operation of aseptic filling machines. The present standard configuration is based on three subsystems: sterile tank, UHT unit/heater and filling machine, each of which has its own control system and an integrated or assigned CIP unit. In this configuration the sterile tank controls the states of the delivery valves as a function of the operating state of the upstream and downstream units. The control system for the cleaning and sterilization of the connecting lines to the interfaces with the other subsystems also resides in the sterile tank (see Section 2). The standard configuration can also be adapted to the case of the direct feeding of the filling machine by a UHT unit/heater. In this case the latter controls the states of the delivery valves as a function of the operating state of the upstream and downstream units. In addition to the proposed standard configuration an optional configuration is described in which the filling machine manages the states of the delivery valve (see Section 3). Illustration of the possibility of external CIP (cleaning in process) units has been dispensed with in the schematic drawings on grounds of simplicity. The exchange of signals between the filling machine and an external CIP unit is dealt with in Section 4. 1 Aseptic packaging machines are packaging machines which pack a sterile product to be filled without recontamination into a container which is usually presterilized in the packaging machine or into a container produced in aseptic manner in the packaging machine (VDMA 8742). Industry Association for Food Processing Machines and Packaging Machines, Page 3/11

4 2 Standard configuration: The process side controls delivery nodes between product line and filling machine 2.1 Schematic illustration of the standard installation configuration in an aseptic filling system Description of signals P: process side (sterile tank or heater) F: filling machine F1 Request for steam barrier Steam barrier is built up by the process side and, accordingly, must be requested by the filling machine when needed. E.g. signal must be present during the whole of sterilization. F2 P1 P2 Steam barrier for product delivery node is active Filling machine sterile (ready for production) Product feed system sterile (ready for production) Signal may only be present when the temperature in the steam barrier of the product delivery node is correct. Signal is present when the sterilization process for the filling machine has been successfully completed 3 and the sterile state is maintained. If this signal drops out in the course of production the product delivery node must be 2 Illustration of the possibility of external CIP/SIP units has been dispensed with on grounds of simplicity. 3 The precondition for sterilization is a successfully completed cleaning operation. Industry Association for Food Processing Machines and Packaging Machines, Page 4/11

5 closed and the steam barrier activated without delay. In this case, depending on the cause of the fault, it has to be checked whether cleaning and sterilization of the filling machine is necessary prior to continuing production. F3 Request for product Only when signal F3 is present may the product delivery node open from the process side in production. F3 presupposes F2 and P2. P3 Product is waiting Product is at the product inlet valve. At the end of production P3 is set to 0 (time-delayed as a function of the filling level of the product line). F4 F5 Machine in production (optional) Useful in the case of process visual display or in the case of production data acquisition and for controlling the UHT unit when filling is direct without a sterile tank (static or dynamic signal). P4 UHT unit capacity signal (optional) Necessary on grounds of quality in the case of direct filling without sterile tank Filling machine ready for Necessary feedback to the process side for cleaning the valve seats in the process side to clean the valve seats of the product delivery valve the product delivery valve. P5 Process side being cleaned Request signal for F Examples of signal exchange Example of signal exchange on sterilization of the filling machine (Initial situation: Filling machine and process side cleaned but unsterile) 1. F1=0 P1=0 F2=0 P2=0 F3=0 P3=0 F4=0 Starting situation 2. F1=1 P1=0 F2=0 P2=0 F3=0 P3=0 F4=0 Request for steam barrier by filling machine 3. F1=1 P1=1 F2=0 P2=0 F3=0 P3=0 F4=0 Steam barrier active. Filling machine can begin with sterilization. 4. F1=0 P1=1 F2=1 P2=0 F3=0 P3=0 F4=0 Filling machine sterile; steam barrier must be maintained by process side when latter is not sterile Example of signal exchange at start of production (Initial situation: Filling machine and process side ready for production) 1. F1=0 P1=0 F2=1 P2=1 F3=0 P3=0 F4=0 Starting situation 2. F1=0 P1=0 F2=1 P2=1 F3=1 P3=0 F4=0 Filling machine production request 3. F1=0 P1=0 F2=1 P2=1 F3=1 P3=1 F4=0 Product is at product inlet valve 4. F1=0 P1=0 F2=1 P2=1 F3=1 P3=1 F4 1 Filling machine in production Industry Association for Food Processing Machines and Packaging Machines, Page 5/11

6 2.3.3 Example of signal exchange on process side at end of production (Process side goes into unsterile state) 1. F1=0 P1=0 F2=1 P2=1 F3=1 P3=1 F4 1 Starting situation: Filling machine in production 2. F1=0 P1=0 F2=1 P2=1 F3=1 P3=0 F4 1 No more product at product inlet valve 3. F1=0 P1=1 F2=1 P2=1 F3=0 P3=0 F4=0 Filling machine has ended production; process side ensures sterile state of filling machine by building up steam barrier at product delivery node 4. F1=0 P1=0 F2=1 P2=0 F3=0 P3=0 F4=0 Process side goes into unsterile state Example of filling machine signal exchange at end of production (Filling machine becomes unsterile) F1=0 P1=0 F2=1 P2=1 F3=1 P3=1 F4 1 Starting situation: Filling machine in production F1=1 P1=0 F2=1 P2=1 F3=0 P3=1 F4=0 Filling machine goes out of production and requests steam barrier F1=1 P1=1 F2=1 P2=1 F3=0 P3=1 F4=0 Process side has activated the steam barrier at the product delivery node F1=1 P1=1 F2=0 P2=1 F3=0 P3=1 F4=0 Filling machine goes into unsterile state. Process side protects itself by means of steam barrier. F1 may be set to "0". Industry Association for Food Processing Machines and Packaging Machines, Page 6/11

7 3 Optional configuration: Filling machine controls product delivery nodes On the filling machine side it must be ensured that in each operating state (even in the deenergized state) the steam barrier at the product delivery node can be activated. To safeguard the process plant it is necessary that the steam barrier at the product delivery node can be verified by means of an independent temperature monitoring device. 3.1 Schematic illustration of the optional installation configuration in an aseptic filling system 3.2 Description of signals P: process side (sterile tank or heater) F: filling machine F1 F2 Steam barrier of product delivery node active P1 Request for steam barrier Filling machine sterile (ready for production) Steam barrier is built up by the filling machine. Signal may only be present when temperature in the steam barrier of the product delivery node is correct. Steam barrier is built up by the filling machine and, accordingly, must be requested by the process side when needed. Signal is present when the sterilization process for the filling machine has been Industry Association for Food Processing Machines and Packaging Machines, Page 7/11

8 P2 Product feed system sterile (ready for production) successfully completed 4 and the sterile state is maintained. If this signal drops out in the course of production the product delivery node must be closed and the steam barrier activated without delay. In this case, depending on the cause of the fault, it has to be checked whether cleaning and sterilization of the filling machine is necessary prior to continuing production. F3 Request for product Only when signal P3 is present may the filling machine open the product delivery node in production. F3 presupposes F2 and P2. F4 F5 P3 Product is waiting Machine in production (optional) P4 UHT unit capacity signal (optional) Filling machine being cleaned P5 Process side ready for cleaning of valve seats in the product delivery node Product is at the product inlet valve. At the end of production P3 is set to 0 (time-delayed as a function of the filling level of the product line). Useful in the case of process visual display or in the case of production data acquisition and for controlling the UHT unit when filling is direct without a sterile tank (static or dynamic signal). Necessary on grounds of quality in the case of direct filling without sterile tank. Request signal for P5 Necessary feedback to allow cleaning of the valve seats in the product delivery valve by the filling machine. 3.3 Examples of signal exchange Example of signal exchange on sterilization of the process side (Initial situation: Process side and filling machine cleaned but unsterile) 1. F1=0 P1=0 F2=0 P2=0 F3=0 P3=0 F4=0 P4=0 Starting situation 2. F1=0 P1=1 F2=0 P2=0 F3=0 P3=0 F4=0 P4=0 Request for steam barrier 3. F1=1 P1=1 F2=0 P2=0 F3=0 P3=0 F4=0 P4=0 Filling machine has activated steam barrier on the product delivery node. Precondition for sterilization of the process side and the filling machine fulfilled Example of signal exchange at filling machine production start (Initial situation: Process side and filling machine ready for production) 1. F1=1 P1=1 F2=1 P2=1 F3=0 P3=0 F4=0 P4=0 Starting situation with activated steam barrier 2. F1=1 P1=1 F2=1 P2=1 F3=1 P3=0 F4=0 P4=0 Filling machine requests product 4 Precondition for sterilization is a successfully completed cleaning operation. Industry Association for Food Processing Machines and Packaging Machines, Page 8/11

9 3. F1=1 P1=0 F2=1 P2=1 F3=1 P3=1 F4=0 0<P F1=0 P1=0 F2=1 P2=1 F3=1 P3=1 0<F4 1 0<P4 1 Process side provides product and releases product delivery valve Filling machine in production Example of signal exchange at end of production on process side (Process side becomes unsterile) F1=0 P1=0 F2=1 P2=1 F3=1 P3=1 0<F4 1 0<P4 1 Filling machine in production F1=1 P1=1 F2=1 P2=1 F3=0 P3=0 F4=0 P4=0 Process side comes out of production and requests steam barrier; filling machine comes out of production and activates steam barrier F1=1 P1=1 F2=1 P2=0 F3=0 P3=0 F4=0 P4=0 Process side goes into unsterile state Example of filling machine signal exchange at end of production (Filling machine becomes unsterile) 1. F1=0 P1=0 F2=1 P2=1 F3=1 P3=1 0<F4 1 0<P F1=1 P1=1 F2=1 P2=1 F3=0 P3=1 F4=0 0<P F1=1 P1=1 F2=0 P2=1 F3=0 P3=1 F4=0 0<P4 1 Filling machine production Filling machine comes out of production and activates steam barrier at the product delivery node Filling machine goes into unsterile state Industry Association for Food Processing Machines and Packaging Machines, Page 9/11

10 4 Signal exchange between filling machine and CIP 4.1 Case 1: Control of cleaning sequence by CIP CIP-F: Signals from CIP to filling machine F-CIP: Signals from filling machine to CIP CIP CIP-F1 CIP-F2 CIP-F9 Filling machine F-CIP1 CIP request CIP ready Medium circulating F-CIP2 Cleaning in progress CIP successfully closed down Preconditions: Filling machine unsterile, not in production and prepared for cleaning CIP available and can provide media of required quality in sufficient quantity. (Optional signal) Feedback (handshake signal) from filling machine to CIP Signal is needed as clearance for the next machine sterilization 4.2 Case 2: Control of cleaning sequence by filling machine CIP-F: Signals from CIP to filling machine F-CIP: Signals from filling machine to CIP CIP Filling machine F-CIP1 CIP request Preconditions: Filling machine unsterile, not in production and prepared for cleaning CIP-F1 CIP ready CIP available and can provide media of required quality in sufficient quantity. CIP-F2 i F- CIP2 i Request for medium i i stands for the various media needed for cleaning. In the case of a specified sequence of cleaning media stored in the CIP only one signal (F-CIP2) is needed. This, however, must then be supplemented by an additional signal F-CIP4: Change of medium and a return signal CIP-F4: Change of medium completed. Requested medium i circulating CIP-F3 i Medium i OK Parameters for the requested medium (conductivity and reflux temperature) are correct F-CIP4 Change of medium Signal in association with CIP-F4 allows control of a fixed sequence of cleaning media stored in the CIP without the need for an individual signal F-CIP2 i, CIP-F2 i and CIP-F3 i to be defined for each medium. Industry Association for Food Processing Machines and Packaging Machines, Page 10/11

11 CIP CIP-F4 Filling machine Change of medium completed Handshake signal for F-CIP4. Signal in association with F-CIP4 allows control of a fixed sequence of cleaning media stored in the CIP without the need for an individual signal F-CIP2 i, CIP-F2 i and CIP-F3 i to be defined for each medium Industry Association for Food Processing Machines and Packaging Machines, Page 11/11