THE PRINTERS GUIDE TO AIR & WATER. The importance of water for paper, printing and packaging. Humidification and Evaporative Cooling

Transcription

1 THE PRINTERS GUIDE TO AIR & WATER The importance of water for paper, printing and packaging Humidification and Evaporative Cooing

2 WATER AS A FACTOR OF PRODUCTION FOR MORE EFFICIENCY The three eements: water, air and heat For many years, the printing industry has been characterised by price wars and over capacities. Cost effectiveness is therefore more important than ever as a means of ensuring competitive strength. Optimising production, processes and operating conditions together with modern buiding technoogy are the keys to success. And water pays its part as a factor of production: for pant, personne and process materias! 1 Quaity Cost The processing of paper, cardboard, foi, abes and other materias is absoutey dependent on the deicate interpay of a wide range of parameters. Paper and other organic materias respond dynamicay to their immediate environmenta conditions. More than in any other industry, the three eements of water, air and heat decide whether or not the production process runs smoothy and achieves the desired eve of quaity. The right water For offset printing, the most widespread technique used for printing newspapers, books and packaging, water is a factor that determines quaity. Mineras such as cacium and magnesium in particuar can cause major probems. Untreated water is unsuitabe for use as process water for producing fountain soutions. The capita outay for a professiona water treatment system is recouped reativey quicky, thanks to process too cost savings and especiay as a resut of the standardisation of the offset printing process. In some cases, the water treated for use in a humidification pant can aso offer the benefit of being usabe for fountain soution production. Optima humidity When working with hygroscopic materias (i.e. those capabe of absorbing moisture), humidity must be kept uniformy constant. In most production processes in the printing and post-press industry, a reative humidity of 50 60% is idea with room temperatures of C. Air that is too dry wi cause materia changes, the buidup of eectrostatic charge, increased dust bonding and heath risks affecting the mucous membranes, eyes and skin. A controed indoor cimate with optima humidity ensures quaity, higher production speeds and fewer process disruptions. Low-cost cooing In many factory buidings significant therma oads due to waste heat from machinery require additiona cooing in order to keep working conditions bearabe for empoyees. In addition, humidity is reative and therefore depends directy on room temperature: the higher the temperature, the ower the reative humidity. The energy costs for cooing an entire production buiding can be enormous. By utiising the principe of evaporative cooing, a direct room humidification system can significanty cut the costs of air conditioning

3 WATER AS A FACTOR OF PRODUCTION TYPICAL PROBLEMS Issues we can hep you with As a factor of production, water affects quaity, costs and time both in the printing and post-press processes. Yet the actua cause of probems in production is not aways immediatey obvious. The tabe beow offers a summary of typica probems experienced in the areas of paper handing and post-press work. Boosting quaity cutting costs i An Idea reative humidity of 50 60% and standardised process water guard against production probems and fuctuations in quaity. Issue Definition Potentia causes How water can hep Air Process Cooing humidity water Setoff Transfer of the fresh printing ink to the back of the foowing sheet in the output stack on the printing machine. Buid-up of static charge on the paper Wavy edges or paper under tension Emusified printing ink Roer gazing Ink roer does not accept printing ink. Water hardness too high Doubing Doube outine of eements of the printed image on the foowing sheet, due to mismatched transfer of the ink transferred from the previousy printed sheet onto the banket. Lack of paper fatness Major differences between temperature and humidity in the press room and paper stack Eectrostatic Sticking of materias together due to static eectricity. Indoor cimate too dry Materias/printing stock too dry Emusification Excessive absorption of fountain soutions by printing ink in offset printing. Proportion of fountain soution too high in the printing ink ph vaue too ow Creasing Excessive deformation of the paper when passing through the printing machine as a web or sheet. Lack of paper fatness Wavy or tight edges Register differences The individuay printed inks are not transferred to the paper s surface to achieve 100% matching coverage, which causes burring of the printed image. Dimensiona changes in the paper Wavy or tight edges Static eectricity Toning Printing of an extra, unwanted visibe coour tone over the entire sheet. ph vaue is suboptima Drying deay Retardation to the printing ink drying process in the stack with sheet- or web-fed offset. ph vaue is suboptima Water as a factor of production Three aspects of cost effectiveness 2 The right water for good print quaity 3 Optima humidity protects the paper 4 Cooing through humidification 5 Fatness in sheet-fed offset 6 Constant humidity for web-fed offset

4 FLATNESS AND HUMIDITY THE CAUSES OF DIMENSIONAL CHANGES Paper is dynamic Incorrect handing and a faiure to keep humidity constant have serious consequences for the fatness of paper and cardboard. As dynamic materias, they are very quick to respond to deviations in equiibrium moisture content. The troube-free handing of these materias in the printing machine their printabiity or runnabiity are greaty infuenced by the humidity. 1 Paper and cardboard printing stock is primariy composed of fibres of pant origin, which is hygroscopic. Materias can gain or ose moisture from and to the air. The degree to which this occurs depends on the materia s equiibrium moisture content, the reative humidity and the ambient air temperature. Equiibrium moisture content Hygroscopic materias seek to bring their absoute moisture content into equiibrium with the ambient air in their environment. This equiibrium moisture content is then achieved once the paper neither gains nor oses moisture to the room atmosphere. Depending on the materias from which it is made, the absoute humidity of the paper (4 9%) is typicay in a state of equiibrium with a reative humidity of 50 60%. If differences between the paper s equiibrium moisture content and the reative humidity are too arge, then the paper wi experience changes due to it gaining or osing moisture causing the paper s fibres to expand or shrink. Reative humidity When assessing room cimate, the interpay of the physica quantities of temperature, absoute humidity and reative humidity must be taken into account: The quantity of water the air can absorb in the form of water vapour depends on the temperature. Warm air can absorb more moisture than cod air. When no more water vapour can be absorbed, the air is said to be saturated, and reative humidity is 100%. The reative humidity is the ratio of absoute humidity (moisture content) and the maximum possibe moisture content for the air at the same temperature. If the temperature rises with absoute humidity constant, then reative humidity fas. For practica purposes, reative humidity is the most important metric for assessing the room cimate, as it is reative humidity that causes dimensiona changes in paper and card. absoute humidity in g/m 3 air re. humidity = x 100 (%) max. absoute humidity in g/m 3 air 2 3 4

5 FLATNESS AND HUMIDITY Infuence of humidity 5 high Depending on the reative humidity, the paper s pant-derived fibres can gain or ose moisture, resuting in the fibres either sweing or shrinking, respectivey. As a resut, the fibres either grow onger (sweing) or become narrower (shrinking). These specific changes to fibre width and ength resut in the paper sheets osing their fatness, causing probems such as misregistration, doubing and wrinking. Paper moisture content (%) ow ow Reative humidity (%) high Tight edges Tight edges is a paper probem that aways occurs if a paper stack with norma moisture content is exposed to ambient air that is too dry. Since reative humidity is too ow, the edges of the sheet ose moisture, shrinking in reation to the midde of the sheet. The paper s edges and corners tighten, causing the sheet to become concave. The tight edges probem typicay occurs in cod weather. Wavy edges Sheets of paper start to deveop wavy edges when the paper s moisture content is ess than the humidity of the ambient air. The edges of the sheets begin to absorb moisture, causing the paper to eongate at the edges whie the midde of the sheet remains unchanged. Wavy edges are therefore the resut of exposing paper that is too dry to a higher humidity or paper with a norma equiibrium moisture content to room air that is excessivey humid. Recommended humidity and temperature eves Appication Temperature ( C) Reative Humidity (%) Paper storage Pre-press Sheet/web-fed printing Digita printing Screen printing Post-press Typicay, there is virtuay no risk of tight or wavy edges occurring for deviations in equiibrium moisture content caused by up to a 5% change in reative humidity. A change of 8 10% in the reative humidity is considered to be a critica threshod for dimensiona changes in the paper. 6 7 Dimensiona changes 1 Corners and edges become curved 2 Humidity affects runnabiity 3 Crucia for sheet-fed offset: fatness 4 Lack of fatness in the stack 5 Paper moisture and reative humidity 6 Tight edges 7 Wavy edges

6 STATIC ELECTRICITY AND HUMIDITY CONSEQUENCES OF ELECTROSTATIC BUILD-UP A highy-charged atmosphere 1 The buid-up of eectrostatic charge can cause serious probems when working with paper, foi and packaging. Static eectricity is the typica resut when non-conducting or poory conducting materias are subject to rapid friction or sudden separation. Optima humidity promotes the harmess dissipation of eectrica charge. The term eectrostatic refers to a positive or negative charge on materia surfaces that is unabe to dissipate. In the printing industry, static eectricity primariy buids up on materias to be processed as a resut of friction or sudden separation such as when feeding the materia through the printing machine. In the printing process, ros and sheets of paper are exposed to high eves of friction from guide roers and thus a risk of static eectricity especiay if roers are coated with rubber or pastic, which cannot dissipate charge since they are exceent insuators. Humidity increases conductivity Paper is a weak conductor of eectricity and its conductivity increases when it absorbs moisture. If its moisture content is sufficienty high, the paper s conductivity is improved to a eve where it can easiy dissipate eectrica charge. On non-conducting surfaces such as pastic roers or inorganic printing stock, such as fois, a thin fim of moisture is formed, which makes the surface conductive enough that a dangerous buid-up of eectrica charge cannot occur. Probems with eectrostatic A critica ower imit for preventing the buid-up of eectrostatic charge is considered to be reative humidity of 40% for the stack and a reative humidity of 45 50% in the press room. If vaues drop beow this imit, then the attractive forces uneashed can cause mutipe sheets to be fed into the printing machine from the input stack, resuting in mafunctions within the paper handing process. Materias with ow grammages respond more dynamicay to static eectricity than papers with a higher weight. In addition, the temporary air cushion separating the printed sheets on the output stack can dissipate too quicky, causing set-off of fresh printing ink onto the back of the new sheet. Poor paper handing in the printing machine can aso resut in misregistration and a substandard printed image. In web-fed offset, excessive eectrostatic charge often causes probems in the foding unit or foded sheet stack. In port-press and book binding, probems with sticking to the foding unit feeder or misfeeding into gathering pockets and cover feeder attachments are aso caused by static eectricity

7 SELECTED PRODUCTION PROCESSES QUALITY CONTROL WITH HUMIDIFICATION Humidity is the soution 5 The right humidity is a quaity factor for many production techniques in the printing and packaging industry. For many speciaised appications and techniques, ony a troube-free production process without deays and at the right quaity can guarantee the desired eve of productivity and profitabiity. Web-fed offset Compared to sheet-fed offset, web-fed offset is ess sensitive with regards to humidity. Serious probems can occur if reative humidity is too ow in the areas where ro stands are used to store unpacked paper ros being prepared for spicing. Here, optima conditions are assured by a target humidity of 50 60%. If this is not provided, two factors can ead to significant probems in production. First, the externa ayers of the paper ros can ose moisture and start to dry out. The shrinkage that resuts then causes significant tension in the paper, eading to tears in the outer ayers or breakages in the spice between the end of one ro and the ro nose, i. e. the start of the next ro. In addition, the paste on the prepared ros can aso dry out prematurey. This resuts in pasting errors during the automated ro changing procedure or web breaks at the pasting point as the paper is fed through the machine. Other negative consequences can incude additiona spoiage, production stoppages and potentia deays in outbound deivery. Digita printing As with conventiona offset printing, dimensiona changes in the materia to be processed and the buid-up of eectrostatic charge are the key probems that are caused by air that is too dry. A ack of humidity aso has a stronger effect on print quaity than in offset. If eectrostatic charge buids up within the machine due to rapid frictiona processes, the pigments can be defected in a diffuse manner between the machine and printing stock. The resut is an uneven printed image that appears coudy, i. e. having aternate bright and dark patches. Packaging In packaging printing and production, optima humidity is aso one of the most important cimatic parameters. For the punching and bonding of chromo-dupex board, a sufficienty high eve of humidity guards against dimensiona changes whie ensuring a 100% fit for the fina, assembed products. When processing and aminating synthetic fois, probems with materias sticking together, materia handing difficuties, set-off issues, creasing and disruptions in ink transfer can a be avoided. 6 7 Static eectricity 1 Humidity reduces static eectricity 2 Mutipe sheets pued off the input stack 3 Misfed sheets 4 Sheets stick together 5 Poypropyene pates become charged 6 Pasted joins dry out 7 Synthetic fois

8 PROCESS WATER ADVANTAGES OF TREATED FOUNTAIN WATER The right water is the key! In print shops, water is used in many appications in rubber banket washing faciities, for humidification and for fountain soution production in particuar. Untreated water from the mains cannot be used as process water in any of these areas. The reason for this is to be found in the arge number of substances in water that can cause serious probems. 1 The quantity of cacium and magnesium sats which determine the overa hardness of the water has a substantia infuence on print quaity. Cacium and magnesium ions have the abiity to bind to the saponifiabe compounds in printing inks to form insoube ime soaps. In the printing machine, these insoube soids are deposited on the inking roers, making these increasingy hydrophiic and thereby impairing the quaity of ink transfer. One effect on the ink roers is gazing, i.e. printing ink is no onger smoothy transferred from the ink fountain to the printing pate. The perfect fountain water has an overa hardness of e CaCo 3 /qq. In this region of average hardness, the formation of ime soaps is no onger a probem. Optima ph vaue Aongside overa hardness, the printing process is aso strongy affected by the proportion of hydrogen carbonate. Hydrogen carbonate neutraises acids, thereby infuencing ph. In offset printing, the fountain soution s optima ph vaue for printing is sighty acidic, in the ph range 4.8 to 5.5. Fountain soution additives are buffered to keep the ph vaue consistent even in the event of factors caused by papers or inks. If untreated mains water has a hydrogen carbonate content of over 150 mg/, some of the acid buffer wi be neutraised. Fuctuations in the ph vaue ead to difficuties with printing, such as deays in drying, toning and excessive emusification. Corrosion For corrosive constituents found in water, namey chorides, suphates and nitrates, printing machine makers define maximum imits, as these compounds are highy damaging. Treated process water protects against corrosion and can increase roer service ife by as much as 70%. Other direct cost-saving potentia resuts from savings made on acohos and other fountain soution additives such as isopropano (IPA), and the reduced need for routine ceaning. Water quaity = process quaity With a water treatment system, any drinking water suppy can be used to produce standardised process water that has constant hardness and a ow hydrogen carbonate content, and is free from corrosion-promoting sats and microorganisms. A cost effective additiona benefit is aso possibe if the treated water can aso be utiised for humidification Image: Fogra

9 COOLING EVAPORATIVE COOLING WITH HUMIDIFICATION Low-cost cooing High temperatures in production areas are a burden on personne, pant and process materias. On the other hand, the cooing of production rooms requires a ot of cooing capacity, resuting in high energy costs. With a direct room humidification system using high-pressure nozzes, the cost of cimate contro can be significanty reduced. Absorbed heat (in kw) Evaporated water (in /h) Temperature pays a crucia roe in the reationship between paper and air: the reative humidity of a room depends on the ambient temperature. A change of 1 C in the temperature corresponds to a change in reative humidity of about 3%. As the temperature fas, the reative humidity rises. Conversey, reative humidity itsef fas as temperatures rise aways assuming that absoute humidity remains the same (see fig. 6). For most production processes in the printing, paper and packaging industries, optima cimatic conditions are typicay achieved with a reative humidity of 50 60% and a room temperature of C. Much too warm Heat gains from machinery in production and post-production faciities are typicay so severe that temperatures are much higher than recommended vaues. One consequence of this is a drop in reative humidity with serious consequences for materia handing and process stabiity. Personne aso suffer by being exposed to these adverse working conditions. By controing the room temperature, businesses can make a usefu contribution to quaity contro as we as increasing empoyee comfort. Evaporative cooing Cimate contro in production faciities often requires a ot of cooing, resuting in high energy costs. With the right design and technoogy a direct room humidification system can reduce the costs of air conditioning or simpy reduce the room temperature independenty of any AC system. This is due to the positive side effect of the high-pressure nozzes, which spray cod water at 85 bar directy into the room s air without causing dropets. The compete absorption of the microscopic, atomised water dropets in the air causes heat to be drawn out of the room. The principe of evaporative cooing achieves an extremey cost effective owering of the room temperature. 100 water from a high-pressure humidification system absorbs around 70kW heat whie consuming ony 0.6kW of energy, achieving a potentia reduction in room temperature of between 2 C and 5 C. Process water and cooing ph vaue of 4.8 to 5.5 is optima Reative humidity (in %) , Temperature (in C) 2 Water determines printing quaity 3 Coour rub-off due to drying probems 4 Corrosion reduces roer service ife 5 Humidification absorbs heat 6 Temperature and reative humidity 7 High-pressure nozze humidifier

10 HUMIDIFICATION TECHNOLOGY AN OVERVIEW OF POTENTIAL SYSTEMS One goa, mutipe options To ensure adequate humidity, the printing industry uses a wide range of systems and technoogies. Nozze or utrasonic fogging units, steam humidifiers and evaporators are the kinds of technoogies typicay depoyed, and differ in terms of energy consumption, maintenance requirements and humidification performance. Water and high pressure 1 In genera, we can distinguish between two basic principes in humidification: direct and indirect humidification. With a direct room humidification system, separate humidification units are instaed directy in the room, and are ceary visibe. With indirect humidification, moisture is added to the air in centraised air-conditioning system and fed into the working area by using a system of ducts and outets. In the printing industry, direct humidification systems are mainy used, primariy because they offer more targeted and taiored contro over humidification. Production areas used for different kinds of work and with different humidification requirements such as paper storage, pre-press and post-press can be humidified precisey according to demand. For speciaised machinery and appications, targeted spot humidification for areas or materias can aso be impemented, to ensure higher eves of humidification as needed. Technoogies The technoogies avaiabe today for use in direct room humidification systems vary in terms of their energy consumption, maintenance costs and humidification capacity. With evaporators, a fan is used to draw in room air, which is then passed over a moist wick. The humidification process itsef is caused by evaporation from the surface of the wick. Whie these kinds of humidifiers require very itte eectricity to run, humidity contro is imited to around +/-10% and the evaporator wicks wi need reguar ceaning, inspection and potentiay repacement to combat microbia growth. Steam-based humidifiers generate steam in a heatproof pastic or stainess stee cyinder, in which the water is heated to 100 C. Steam humidifiers are hygienic, since microbes and bacteria are reiaby kied off by this process. For eectric steam humidifiers, energy consumption is high, as are the service requirements, due to the need to manage the ime scae that buids up. With spray humidifiers, water is aerosoised aowing it to be readiy absorbed by the air. The aerosoisation process can either be carried out with utrasonic osciators, through the use of compressed air or by spraying the water under high pressure. Spray humidifiers can humidify arge interior spaces whie consuming very itte energy. The use of water treatment pant in combination with these systems removes mineras from the suppy water, providing dust-free humidification. 2 3 Steam 4 Air Steam Air Aerosos Water suppy

11 HUMIDIFICATION TECHNOLOGY HYGIENE AND MAINTENANCE State-of-the-art technoogy In recent years, many companies have repaced steam and compressed-air humidifiers with high-pressure nozze systems. These systems use a highpressure pump and specia nozzes to atomise the water into a fine mist as part of a virtuay sient process. Energy consumption is aso ony a fraction of typica vaues for nozzes powered by compressed air or steam humidifiers. The adiabatic cooing effect of cod water evaporation aso creates a peasant indoor cimate. To ensure operation is hygienic and troube-free, ony utra-pure, demineraised water is used provided by a reverse osmosis pant that is integrated into the humidification system. In faciities where the water treated for use in the humidification system can aso be used as standardised process water for the printing presses, there is a practica and cost-effective additiona benefit. Maintenance is a must A humidification system is ony as hygienic, safe and reiabe as the process water, and the service and maintenance mode that is in effect. Even if it appears cear and pure, and is perfecty suitabe for use as drinking water, untreated water wi typicay be unsuitabe for use in most humidification systems. This is because of the arge number of substances found in water: bacteria, microbes, agae, suspended partices, sats and other mineras can pose a threat both to human heath and the functiona capabiity of humidifiers. Typicay, a reverse osmosis pant is used for the treatment of the water to be used in humidification systems. Despite optima pre-treatment of mains water with a softener and fitration stages, undesirabe deposits can sti form on reverse osmosis membranes and other key components within a humidification system. These are not ony capabe of seriousy compromising the performance and service ife of the pant, but aso and above a present a serious risk to human heath. Routine inspections, maintenance, disinfection and the repacement of heaviy worn system components are therefore absoutey essentia for the safe and hygienic operation of the humidification pant. Detais of the hygiene standards of the various humidification systems can be obtained from certificates issued by independent testing abs and from manufacturers maintenance and service programmes Humidification technoogy 1 High-pressure nozze humidifiers 2 Steam humidifiers 3 Utrasonic humidifiers 4 Water treatment for high-pressure nozzes 5 Microbes and bacteria must be avoided 6 Routine maintenance 7 Interna hygiene monitoring

12 CASE STUDY HP INC., BARCELONA Speed and quaity in digita printing At its 4,000 sqm Demo and Training Centre in Sant Cugat de Vaès (Barceona), HP Inc. presents its customers with the atest digita printing technoogy, from arge-format printing to packaging and job printing. To ensure optima resuts for print and production, the HP Demo and Training Centre requires air humidity vaues to be kept constant. 1 Every year, over 6,000 deegates from the EMEA region visit the Demo and Training Centre of this eading digita printing speciaist to seek inspiration and participate in training. The Spanish site views itsef as Dream Factory that aims to stimuate and foster new customer product ideas, and demonstrate the digita printing techniques for turning them into reaity. To ensure optima resuts for print and production, the HP Demo and Training Centre requires air humidity vaues to be kept constant. Eectrostatic charge, changes to the paper dimensions and fuctuations in print quaity a adversey affect our training and demonstration work, expains HP Trainings Manager Adam Godthorp. In addition, says Godthorp, the various printing technoogies and materias (e.g. pastic, cardboard) aso need different eves of humidity for processing. The existing centraised ventiation system with steam humidification was no onger abe to hande the requirements and was accordingy decommissioned. Since 2013, a direct room humidification system with high-pressure nozzes has been ensuring constant, optima humidity. Simpe instaation Over 50 high-pressure DRAABE TurboFog Neo humidifier units guarantee controed humidification in various areas and parts of the buiding. Forinstaation, HP Inc. merey required a mains water system and drain, pus an appropriate eectricity suppy. Everything is suppied to the buiding from a centra mechanica room, where both the water treatment systems and the high-pressure pump are instaed. These systems are connected to the humidifiers using speciaised highpressure hoses and contro ines. The compact humidifiers, attached to ceiing suspension or wa-mounted are each oriented both horizontay and verticay in the various rooms to ensure optima humidity distribution. High-pressure nozzes spray out an utra-fine fog with a dropet size of ess than 15 µm, which is immediatey absorbed by the air and uniformy distributed within the room. Lower energy costs The required humidity is reguated using a digita contro system. In each of the individuay defined humidification zones (rooms or parts of rooms), contro units measure the current eve of humidity and activate the humidifiers when it fas beow the set target vaue. This means that rooms can be humidified individuay, or exacty as required for their various uses

13 CASE STUDY For José Baena from HP Inc. Goba Rea Estate, the new technoogy offers major advantages: We now have optima vaues across the various zones and printing systems. And we ve aso managed to cut energy consumption for humidification by over 95%. The energy-efficient high-pressure humidification system ensures a constant reative humidity of 50 65%. Depending on the printing process and materia, the reative humidity in the Demo and Training Centre can be adjusted quicky and increased for printing onto pastics, for exampe. Automated maintenance Both the high-pressure system and the corresponding water treatment unit are instaed in sma portabe containers that aow quick repacement and servicing. The reverse osmosis system used for water treatment de-mineraises and ceans the mains water of impurities. Every six months, these containers are automaticay repaced at HP Inc. with fuy maintained and ceaned systems. The used systems can be easiy reeased from their wa brackets and sent back to the manufacturer for servicing where they are dismanted, inspected, rinsed out and ceaned. Worn parts are repaced and technica updates instaed. Humidity is a must For HP Inc., zero maintenance, aincusive service and the individua humidification soutions were the key reasons for picking the new highpressure nozze-based technoogy. Since then, the DRAABE humidification system has been providing individuay adjusted, optima humidity throughout the Demo and Training Centre, so as to protect against static eectricity and dimensiona changes in printing stock. Impressed by the positive experience gained in their use, HP Inc. aso depoys high-pressure nozze systems for quaity contro at internationa trade fairs: at drupa 2016, the word s fagship trade fair for the printing industry, an entire exhibition ha was fitted out with a humidification system. My team and I were reay peased to see the effects of a perfecty baanced reative humidity on our machine demos and the genera room cimate, reports Rotem Sagi Shteinmetz, Operations Manager in HP Inc. s drupa Team, summarising the importance of optima room humidity. Fact fie Humidification: 54 high-pressure fogging units Space: 18,000 m 3 Required humidity: Commissioning: to 65 % RH i 5 6 HP Inc., Barceona 1 Demo and Training Centre 2 Humidity protects against static eectricity 3 High-pressure nozze humidifier 4 Individua positioning 5 Repaceabe water treatment units 6 Rotem Sagi Shteinmetz

14 CASE STUDY HEIDELBERGER DRUCKMASCHINEN AG, WIESLOCH-WALLDORF More than machines With the Print Media Centre (PMC) Commercia and Packaging, Heideberger Druckmaschinen AG in Wiesoch-Wadorf operates the word s argest showroom for commercia and packaging printing. Optima humidity and standardised process water increase performance whie ensuring a troubefree printing process. 1 More than machines is the caim asserted for the two fuy equipped print shops, spread over an area of about 10,000m 2, where the primary focus is on the integrated overa processes and the required components. With its comprehensive portfoio of offset and digita machines, software, consumabes and services, the PMC covers any and every topic ikey to be faced by a modern, industria-scae print production business. Over 1,200 individua customer demos are hed yeary, educating internationa deegates in how rea-word production processes can be organised to be more economica and more reiabe. The Print Media Centre Heideberg forms part of the Goba Print Media Centre Network. Other members incude the Print Media Centre Atanta in Kennesaw and the Print Media Centre Shanghai in Qingpu, which serve the US and Asian markets respectivey. Faut-free sheet feeding To ensure optima cimatic conditions for machine demonstration work, the PMC Commercia, opened in 2015, contros reative humidity with a highpressure nozze system featuring the atest generation of humidifiers. Our presentations have to be right on the money and must not be disrupted by wavy or tight edges or eectrostatic buid-up on the paper. Perfect sheet feeding is a basic requirements for our demonstrations, expains Head of Print Media Centre Roand Krapp. In choosing its humidification system, Heideberg can draw on amost 20 years of experience: the first highpressure humidifiers were instaed in Heideberg s manufacturing faciities back in Over 200 units are now in use, ensuring that printing and testing in the assembing has proceed as intended. Water treatment The right water pays a major roe in ensuring the quaity of offset printing at PMC Commercia. Accordingy, germfree, demineraised water is produced as part of a muti-stage process both for the high-pressure nozze fogging units and as speciay treated process water for the printing machines. The process begins with water softening. Here, the cacium and magnesium sats responsibe for water hardness are repaced with readiy soube sodium sats. Once treated, this soft water is then purified by being passed through a two-step mechanica fiter stage

15 CASE STUDY This separates out soid contaminants with a partice size of up to fivethousandths of a mm. The heart of the water purification process is the third stage, reverse osmosis. Here, a membrane separation technique is used to effectivey steriise and demineraise the pre-treated water. The reverse osmosis process is entirey sef-contained and runs in a portabe, compact modue that enabes the comprehensive maintenance and disinfection of the pant by simpy repacing the entire modue. This standard service is performed by the manufacturer automaticay at haf-yeary intervas. From the reverse osmosis pant, some of the pure water produced is fed directy to the humidification system. Process water as an additiona benefit To produce the fountain soution, the 95% demineraised water passes through a fourth process stage, in which a speciaised hardness concentrate is added to the water. After this standardising step, the process water now has a residua hardness optimised for offset printing and is routed to the Heideberg printing machines via a separate suppy ine. Some of the treated water is aso hed in reserve as a fountain soution for subsequent use, in a separate tank. By depoying this standardised process water, Heideberg ensures that the ink/water baance for the ink in the machines remains stabe, and that toning, roer gazing or setoff does not occur. The water has a constant quaity, with a ph vaue between 4.8 and 5.5 and a hydrogen carbonate content of ess than 150mg/. For personne and pant At Print Media Center Commercia, optima humidity and standardised process water are key parameters that guarantee maximum performance whie avoiding disruptions to the printing process. In seecting its humidification system, Heideberger Druckmaschinen AG has devoted particuar attention to maximising operationa reiabiity and constant hygiene, emphasises Roand Knapp: Requirements for occupationa safety and heath as we as maintainabiity were reviewed in great depth by the speciaist departments beforehand. And we are very happy with the resut: Our new humidification system reiaby creates the conditions required for peak performance by our personne and pant. Fact fie Humidification: 36 high-pressure fogging units Space: 4,700 m 3 Required humidity: 45 % RH Commissioning: 2015 i 5 6 Heideberger Druckmaschinen AG 1 Print Media Center Commercia 2 Printing machine at PMC 3 High-pressure nozze humidifier 4 Optima: humidity and process water 5 Water treatment at PMC Commercia 6 Expert know-how at Heideberg

16 HUMIDITY AND PROCESS WATER This brochure has been produced in cose consutation with Fogra. We thank Fogra warmy for their support and the photographic materia suppied: FOGRA Graphic Technoogy Research Association Condair pc Artex Avenue, Rustington, Littehampton, West Sussex, BN16 3LN, UK Te: +44 (0) uk.saes@condair.com -