Wellness in the stable

• What was needed: igubal ® Flange bearing
• Requirements: Freedom from lubrication, maintenance and corrosion
• Industry: Agriculture
• Success for the customer: In contrast to conventional metal bearings, the plastic spherical caps do not get stuck due to heavy soiling

When a new barn is built in Germany, it is almost always a free-range barn. It is characterised by the fact that the animals can move around freely and are no longer tethered. Cow cleaning machines, which are installed for reasons of animal welfare and comfort for the animals and are subsidised in some countries, are often part of these barn systems. There are 50 to 60 animals per cow scratching brush. Cows need to scrub and scratch themselves. This is how they clean themselves and rid themselves of parasites, lichen and mites. Brushing stimulates and energises the blood circulation. Calculations have shown that the scratching brush is in use for at least seven hours a day. This fully automatic cow cleaning machine 'CowCleaner DUO' is a double brush system. The vertical brush is the counterpart to the tree trunk and is used particularly intensively. The advantage of the double brush is that the cow can not only scrub and scratch its sides and back, but also its neck. "Cows can also get angry. If the system doesn't work straight away, they become aggressive and attack the machine," Lechner points out. It is therefore important that the overall design of the cattle scratching brush is robust.

Activating the brushes is simple. They are mounted on a kind of carriage system. If it is lifted a few centimetres, the brushing process begins for 60 seconds. During the brushing process, the entire brush is constantly moved up and down by the animals. Added to this is the force of the cows, which constantly act on the system. In reality, it is very difficult to calculate this precisely. The industry generally relies on experience and testing. Ammonia vapour in the barn, cow hair and hay and straw dust also have an effect on all components. If the brush system is installed outdoors, there are also the effects of the weather. "After a week in use, you won't recognise the machine," confirms the product developer.

The lubrication-free plastic flange bearing is installed with two mounting holes on the underside of the cow cleaning machine. It reliably absorbs the rotary movements. It is resistant to vapours, fine dust and coarse dirt. It is also UV-resistant. "Metal ball bearings seize up immediately in these aggressive environmental conditions. Downtime is inevitable," explains the technical sales consultant from igus®, Thomas Weber. "Dirt increases wear. However, the absence of lubricants means that nothing can stick to the bearing, which would affect the downtime and therefore the service life." Another major advantage in this application is that precise alignment of the bearing housing is not necessary, as the flange bearing automatically compensates for misalignment. The gearbox is fixed at the top. As the mounting for the gearbox cannot always be the same, the angle of the shaft to the carriage may also be different. This is compensated for by the angle compensation of the igus®-bearing. "If this angle compensation were not used, we would have to place much higher demands on the dimensional accuracy of the welding work and re-mill if necessary," explains Lechner. "This must be avoided for cost reasons."