Clean design – the new look in pneumatics

Implementing just a few key design details can be enough to eliminate numerous potential contamination hazards in food factories, such as bacteria, chemicals or corrosion particles.

Intelligent solutions, such as corrosion-resistant ‘Clean Design’ pneumatic components, now even offer a directly-integrated field-bus interface. Automation components therefore support the implementation of HACCP concepts, rendering especially critical processes, such as milk processing, safe.

Pneumatic systems provide a wealth of functions in the food and packaging industry, for example, actuators for flaps and filling, cutting, clamping, sorting or closing devices. Many global companies in this industry therefore work closely together with leading manufacturer of pneumatic automation technology Festo to benefit from the holistic individual system solutions that it offers.

In the past, the most important feature of a standard Festo drive was its functional design and the ease with which it could be fitted with accessories such as mounting components or proximity sensors. However, the food industry has a further priority – easy cleaning. Festo’s product developers therefore simply transformed a drive with standard functionality into an easy-to-clean design. This has resulted in the world’s first actuator with integrated cylinder sensors – and a completely smooth corrosion-resistant surface.

Product development guidelines
In the past, international design standards at the equipment side have served as product development guidelines, representing a mandatory HACCP prerequisite (hazard analysis critical control points). Risks and dangers can be recognised, evaluated and prevented with the HACCP concept. For system operators and consumers alike, active prevention is the best protection against the risks involved with food production.

With the help of HACCP, food producers are able to define and monitor critical points within their production processes by specifying such points within the process, along with associated limit values. This systematic monitoring allows for immediate correction in the event of a critical situation or contamination, for example with bacteria, metal particles or lubricants. The foremost priority is food safety.

Although the HACCP system is based upon a functioning quality and hygiene management system, it nevertheless functions independently of these instruments. Festo’s Clean Design products are an example of some of the helpful prevention tools available today.

Components
Clean Design components completely fulfil the hygiene requirements of machinery for the food and packaging industry. The Festo pneumatic norm cylinders CDN, round cylinders CRHD and compact cylinders CDC, valves and valve terminals are made of corrosion-resistant materials and conform to all relevant worldwide standards. This includes their totally smooth surface finish and the associated connectors, which have no exposed threads. The radii of the components have been made as large as possible, and edges, corners and small cavities have been avoided.

There have been similar developments in valve terminals. Festo has developed the world’s first valve terminals suitable for wet environments, which have no need for the protection of a control cabinet. This eliminates any problems resulting from the formation of condensation in cabinets.

Diagnosis = ‘Corrosion-free’
But Festo is offering even more – field-bus networking together with Clean Design. The DeviceNet field bus is used to connect up CDVI-DN valve terminals in a way that saves a great deal of installation work and also offers diagnostic facilities. The result is it is possible to implement preventive maintenance in the form of a ‘condition monitoring’ system for the number of valve switching cycles completed (and thus drive travel), which cuts downtime. It is only with a field-bus connection that valve functions can be monitored continuously. This allows machine operators to intervene even before malfunctions and possible system failures occur. At the same time, the turnkey field-bus system reduces the required installation time. The modular or static EDS files (electronic data sheets for DeviceNet) supplied with the terminals ensure fast and convenient commissioning.

To meet customer-specific needs, the company also offers CDVI-PL valve terminals with Powerlink. Powerlink is a time-synchronous variant of fast Ethernet, which even provides Festo’s corrosion-resistant valve terminals with a real-time capability, allowing them for the first time to be used for time-critical applications. CDVI-PL is the first valve terminal in the world with a real-time-capable fast ethernet protocol.

A modern Milky Way
In industrial dairies, the products of manufacturers such as FlexLink, Krones and Elopak ensure high quality standards all the way along the process chain, from the feeding of packaging materials through labelling and filling and on to the transfer of the filled packs to the standard wheeled containers used in this industry. Hygienic pneumatic valve terminals and cylinders from Festo provide reliable automation on a modern ‘Milky Way’.

Because of its protein content, milk as a foodstuff can very quickly and easily spoil and, if handled incorrectly, can become unfit for consumption, even poisonous within hours. It is therefore vital for milk processing plants to be designed to high international hygiene standards in order to avoid chemical contamination and bacterial and fungal infestation. Plant designers are, however, subject not only to technical demands but also increasingly to economic pressure. Worldwide, the large food companies dominating the market are pushing prices down with the result that dairies must automate their processes still further in order to cut costs.

Always zthe right answer
FlexLink, Krones and Elopak have worked together with Festo to find answers to the demands for automation, not only in dairies but also in bottling and canning plants for everything from soft drinks, mineral water, beer, wine, edible oils and other liquid foodstuffs. The machines and components offered by these companies provide the highest possible level of protection against contamination in the food and splash zones.

Linkage from beginning to end
FlexLink of Sweden uses conveyor systems to link individual stations within a filling process – for example, to bring packaging materials to a filling machine or plastic and glass bottles to a labelling station. The conveyor systems, with non-porous water-repellent stainless-steel surfaces, can be cleaned quickly and require no lubrication. The shaped stainless-steel guide profiles create a linkage system, which connects together modules without the need for any welding or laborious mechanical installation.

The return chain of the conveyor system runs within separate plastic trunking, which protects it from product fragments or liquid leaks from the upper conveyor chain. It is also possible to fit antibacterial plastic components to prevent the spread of infestations. “In these conveyor and distributor systems, we use Festo ADVU compact cylinders as rotary and clamping stopper cylinders,” says General Manager of FlexLink Germany Peter Nauwerck. “The compact cylinders are just as powerful as standard cylinders but take up only half as much space. Among the other Festo components used for the pneumatic automation of the systems are CPV valve terminals, controlled via AS Interface, and D-series service units, which means we can be sure of total pneumatic compatibility and are able to obtain everything we need from a single source.”

More than just milk
System supplier Krones offers solutions for the filling process in dairies involving a range of products from skimmed milk, drinking yoghurt and cream to mixed milk drinks containing fruit and grain. The company’s filling machines place the dairy products in plastic containers (PET, HDPE) of different shapes and sizes as well as glass containers.

This supplier covers all the central steps in the filling process, from stretch-blowing of PET bottles, rinsing and filling with dairy products through to sealing and labelling. Aseptic filling plants are today’s state-of-the-art. The filling and sealing machines feature a ‘hygienic design’ with easy-to-clean inclined surfaces and the options of gutters to catch product residues and automatic spray cleaning and disinfection of external surfaces.

Individual solutions
For the pneumatic automation of its systems, Krones relies on the well-proven products offered by Festo. Stainless-steel cabinets house CPV valve terminals controlled via AS Interface. “This means that our systems remain highly flexible with regard to future expansion,” explains Dr Albrecht Hoene, Head of Component Development at Krones. “The easy-to-use AS Interface bus system and Festo’s compact CPV valve terminals are the ideal way implementing Krones’ modular concept.”

The valve terminals are equipped with a special multiple-connection sub-base made of POM. This is used to couple all the necessary tubing connections out of the control cabinet. Outside the control cabinet, the tubing connections for the drives are made via ready-installed stainless-steel fittings, thus meeting the stringent requirements of the food industry.

Turnkey solutions
The labelling machine, too, shows how Festo has met the individual demands of this system supplier from Bavaria. Festo, as an automation supplier, provides Krones with service units and pneumatic modules as turnkey units – fully tested and with a guarantee and documentation. This means less work for Krones’ in-house planning, purchasing and production personnel and means that the company has only one order, one delivery date and one supplier to deal with. All that Krones needs to do is bolt the mounting plates and service units into position and make the tubing connections for the actuators – in other words, simply ‘plug and work’.

At the end of the Milky Way
Once the packs have been filled, the filling process is completed by the conveyor systems supplied by the materials handling division of Elopak, a company with bases in Finland and Norway. Within a wheeled container packing system, the filled packs are first grouped together and then loaded onto the individual levels of a container. A grouping unit is used to transport the wheeled containers via transfer vehicles onto the storage tracks of a cold store. A short time later, they will be on display in the refrigerated cabinets of supermarkets and grocers’ shops.

Splash zones
Elopak also installs wheeled-container washing machines and lifters, which return empty wheeled containers to the packing process. As all the associated machinery is located in splash zones, where hygiene requirements are very stringent, the system designers have relied on Festo’s Clean Design product line of valve terminals and cylinders. With completely smooth corrosion-resistant surfaces, these products are very easy to clean. Their connections have no exposed threads, and all components have large radii, without sharp corners, edges or cavities. This eliminates many possible hazards that could otherwise result from bacteria, chemicals or corrosion particles.

The Clean Design valve terminals are the ideal choice for wet environments, offering the high degrees of protection IP65 and IP67. They are able to operate without the protection of stainless-steel control cabinets. This means that they can be mounted directly on machines, even in hygienically critical applications. The practical result is that space is saved in the control cabinet. “This is the ideal equipment for filling processes,” confirms Lauri Nurminen, Sales Manager of Elopak Materials Handling.

CDC – clean design compact cylinder and more

The CDC is a brand new addition to Festo’s product offerings in the area of clean design components, and represents a clean design variant of the ADN compact cylinder in accordance with ISO 21287, which has proven its worth for many users in the field of factory automation. Within the clean design product range, it’s the compact version of the CDN standard cylinder used, for example, by Elopak. It’s utilised wherever maximum resistance to corrosion and ease of cleaning are imperative. The integrated end-position sensing system used in the CDC is the easiest to clean sensing system available on the market today. Installation expense is minimal, because the cylinder sensors are pre-assembled and adjusted.

All of Festo’s clean design components have three features in common: they’re highly economical, safe and convenient. Clean design products are economical because they result in less downtime, and thus lower costs, thanks to shorter cleaning times. They have a long service life and are very reliable, because they’re highly resistant to corrosion and media. Good system reliability is assured by materials that are suitable for contact with food products. System developers can conveniently order a broad range of variants, which can be individually configured.

Together with the CDN cylinder, the CDVI valve terminal, QS-F fittings, PLN/PFAN tubing and the stainless steel product ranges, Festo offers users the most comprehensive spectrum of products for demanding and durable pneumatics – everything from a single source, everything plug and work.

www.festo.com/food

HACCP principles

These are oriented solely towards food safety and quality criteria. Machines and systems must be furnished with the right technical equipment and adequate space to this end, using Clean Design or Hygienic Design products. These prevent biological hazards thanks to maximum ease of cleaning, as well as physical and chemical dangers thanks to the use of suitable materials and lubricants in compliance with FDA regulations and NSF-H1.

Suitable hygienic measures fulfil HACCP principles as well. These include the right temperature and relative humidity, as well as adequate isolation from work processes and production lines for the prevention of cross-contamination. Personnel hygiene, suitable pest control and implementation of the necessary cleaning and disinfection procedures are just as important.

The three risk factors involved with the use of pneumatic automation technology in food production include biological, physical and chemical dangers. Where design, utilised materials and lubricants are concerned, automation products such as the CDN standard cylinder, the CDC compact cylinder, the CRHD round cylinder and the CDVI clean design or hygienic design valve terminal have been designed especially for use in all food zones, and are HACCP certified.