Cutting-edge pneumatic components guarantee reliable and cost-effective production. As the major company within Bavarian Dairies, the Bayerische Milchindustrie e.G.(BMI), plays an extremely important role in the German dairy industry.
With its main activity being processers of milk and whey, decades of experience and investment in state-of-the-art production facilities has enable BMI to offer excellent, user-friendly, raw materials to the food, pharmaceutical and cosmetic industries in addition to its core production of traditional fresh milk products such as, hard, semi-hard and blue cheese.
This focus on high quality standards has helped guarantee BMI a strong market position and today more than half of its 350 plus product range is exported around the world.
BMI currently has 11 sites in Germany at which around 2.8 million tonnes of raw material (milk) is processed every year.
At their Windsbach plant, 500,000 litres of locally produced milk is delivered every day to be processed for the production of cheese. At this site, under the trade name Paladin, BMI produce a total of 15,000 tonnes of semi-hard cheese a year using a three-shift production pattern working 6 days a week. However the milk continues to be delivered to the plant on a daily basis.
Continuous production takes place in the drainage area of the plant, where the whey/water/curd mixture is filled into column-shaped drainage systems. This constant filling process, which applies pressure to the mixture, helps to remove the unwanted whey and water from the mixture via drainage inserts. Following this process, the curd, including any leftover whey, is collected in the lower section of the columns where it is filled into cheese moulds.
The moulds are then subjected to constant pressure, using pneumatic cylinders which exert a precisely set pressure on the mould lids, for a period of around one hour. As the cheese moulds are perforated, any leftover whey from the curd is simply and efficiently squeezed out of the mould. Once this has been completed, the cheese barrels are placed in a salt bath where any remaining water and whey is removed using an osmotic process and the rind of the cheese begins to form. Once matured the cheese is then finally ready for packing.
During this manufacturing process the various machine components are exposed not only to whey and water but also steam and Clean in Place (CIP) products, such as caustic soda and nitric acid.
BMI´s cheese production process requires maximum reliability as any unscheduled stoppage not only means lost production but also entails considerable expense as the entire plant must be completely cleaned before it can be restarted once a fault has been rectified.
To ensure that the complex production lines operate fault-free, personnel in MBI´s Machine Centre are continuously looking for components which show a greater ability to withstand the strains of continuous operation and exposure to environmental media, whilst offering maximum safety and durability.
In addition to the regular maintenance work undertaken by the original machine manufacturers (OEM´s), plant modernization measures have also been introduced by in-house Machine Centre’s Team. This has ensured that the plant always meets the high levels of hygiene standards required and is always up-to-date with the latest technology.
The plant runs 24 hours a day, including the intermediate cleaning procedures. This means that the plant must be serviced in such a way as to ensure that there are no unscheduled stoppages.
Previously compressed air ISO cylinders made of aluminum were used throughout the plant but this posed two problems. Firstly the thread on the cylinder’s piston rod did not meet ISO compliance and secondly, the cylinder’s aluminum construction was not resistant enough to the environmental media (whey, CIP liquids, water). This resulted in the need to replace the cylinders packing seals every six months along with the additional expense of operating a costly on-going maintenance program.
The challenge facing BMI was to find a range of maintenance friendly ISO compliant cylinders, with an approved piston rod and a stainless steel body construction, that are resistant to the cleaning agents used in the plant. Plus the BMI Machine Centre Team added to their wish list, the need for an adjustable stainless steel mounting bracket, a wiper ring on the piston rod, to prevent dirt from entering the cylinders, and finally the ability to replace individual components without having to totally dismantle the complete cylinder.
Given that SMC´s ISO cylinder C95SDB completely meets these criteria in addition to extra benefits such as excellent continuous load performance; BMI´s engineering experts had no hesitation in specifying these stainless steel cylinders for use in their plant.
Available in various diameters, with intermediate stroke options and unparalleled choice of thread and piston material, SMC´s C95 cylinders are now used extensively throughout the plant at various points where spray from whey, H2O or CIP needs to be considered. These “critical” points within the cheese production process specifically include the lid positioners, handle conveyor and the in-feed areas of the plant.
BMI´s Machine Centre Team have confirmed that since the introduction of these stainless steel cylinders, life cycle performance has now been extended fourfold when compared to the previous aluminum cylinders and that cylinder maintenance is now only required every two years!
According to BMI Machine Centre’s Michael Rissling, “SMC´s C95 stainless steel cylinders, fitted with standard wiper rings, have dramatically reduced our overall cylinder costs as they are completely resistant to both environmental media and cleaning agents due to their 304 SUS construction. With various rod thread and mounting options, these cylinders offer us excellence performance as well as simple, non-complicated, replacement part maintenance as and when required.”
Following the outstanding success of this cylinder solution, BMI´s Machine Centre Team had no hesitation in asking SMC to help them try to improve their existing valve performance used in the filling process.
Facing similar environmental media challenges as the cylinders, the existing valves depending on the running time, had to receive maintenance every 6 to 8 months.
Michael Rissling added, “We were looking for replacement valves that offered us a number of important features. The valves had to be ISO compliant, compact, without any rubber in their construction, and they had to offer a high flow rate and low power consumption performance. And finally, we needed a range of valves that could offer us a longer, maintenance free, life cycle.”
With their extensive knowledge of the harsh environmental challenges faced in the Windsbach plant, SMC experts had no hesitation in recommending their ISO compliant VS7 and VFS Series to BMI.
These 5/2 and 5/3 way solenoid valve ranges incorporate a steel seal in their construction and are guaranteed to deliver 200 million switching cycles, thereby offering an operating life cycle at least four times higher than conventional O-ring sealed valves.
Rissling concluded, “Although we had to make a small modification to accommodate the VFS valve in the control cabinets this valve has still proved to be more cost-effective and it has also introduced a newer, state- of- the-art component to the plant. The collaboration between our Machine Centre personnel and SMC´s Food Industry experts has considerably reduced our operational costs and also helped improve plant safety.”