Flange Bearings for Cow Cleaning Machines

• What was needed: igubal® EFOM flange bearing
• Requirements: Durability, 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 difficult environmental conditions.

When a new barn is built in Germany, it is almost always a free-range barn. The animals can move around freely and untethered. Cow cleaning machines are installed for animal welfare and comfort are often part of these barn systems and are even subsidized in some countries.

Cows need to scrub and scratch themselves. This is how they clean themselves and rid themselves of parasites, lichen and mites. Brushing also stimulates the blood circulation and improves metabolism. Each brush is used for 50-60 cattle.

Calculations have shown that the scratching brush is in use for at least seven hours a day. This fully automatic cow cleaning machine "HAPPYCOW Duo", is a double brush system. The advantage of the double brush is that the cow can not only scrub and scratch its sides and back, but also its neck. The vertical brush is similar to a tree trunk and is used particularly intensively. Activating the brushes is simple. They are mounted on a kind of carriage system. If it is lifted a few centimeters, the brushing process begins for 60 seconds.

During the brushing process, the entire brush is constantly moved up and down by the animals. In addition, the forces exerted by the cows continuously act on the system, making precise calculation for the system requirements difficult.

"Cows can also get angry. If the system doesn't work straight away, they become aggressive and attack the machine," Martin Lechner, Product Development Albert Kerbl GmbH, points out. It is therefore especially important that the overall design of the cattle scratching brush is robust.

Due to the difficulty in making precise calculations, the industry instead generally relies on experience and practical testing. Factors such as ammonia vapors in the barn, as well as cow hair, hay, and straw dust, place additional stress on all components. When the brush system is installed outdoors, weather exposure further increases the demands on the equipment. "After a week in use, you won't recognize the machine," confirms the product developer.

The dry-running 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 designed to withstand vapors, 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 external lubricants means that nothing can stick to the bearing, which would affect the downtime and therefore the service life."

Another major advantage of igubal 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 handled by the angle compensation of the igus®-bearing.

The sophisticated selection and configuration aids available online on the igus® website played a major role in this. Although no load data could be provided for the calculation, the product developer quickly found the right solution. Even the unit price was immediately available online, so that a rough cost calculation could already be presented during product development. A standard machine element is used, which is available from stock.

"If this angle compensation [of the igus bearing] was not used, we would have to place much higher demands on the dimensional accuracy of the welding work and re-mill if necessary. This must be avoided for cost reasons," concludes Lechner. "When we made the internal decision to design a fully automatic cattle scratching brush, it was clear from the outset that we would also rely on the design and economic advantages of plastic.