Fewer failures in overhead conveyors with new lubrication-free ball bearing from igus

igus develops maintenance-free hybrid ball bearing from the xiros series for dirt-resistant operation

Dusty environments can become a problem for overhead conveyors in industry and logistics. When particles settle on conventional metal bearings, deposits cause sluggishness and, in the worst case, failure. To solve this problem, igus is launching a new hybrid ball bearing from the xiros series. Made of stainless steel and high-performance plastic, it allows for lubrication-free and therefore dirt-resistant operation with a load capacity of up to 39kg.

In industry and logistics, it is important to transport goods and workpieces between different production and storage areas as fast as possible with minimum space requirements. Overhead conveyor technology is often used. "Design engineers are currently endeavouring to make these systems more efficient as users are increasingly less accepting of downtime and breakdowns. Even short interruptions can cause high costs and delays," says Marcus Semsroth, Head of Business Unit xiros Polymer Ball Bearings at igus. One lever for greater efficiency is replacing the ball bearings with which the trolleys move on aluminium profiles. "For this purpose, we have launched a new hybrid ball bearing from the xiros series. It makes overhead conveyors more fail-safe and requires less maintenance," says the ball bearing expert.

Dirt resistance leads to fewer failures

In most overhead conveyors, the carriages move on standard metal ball bearings. They are degreased and filled with low-friction oil to reduce friction. The problem: the low-viscosity oil can leak out at the seals. It then attracts particles, particularly in dusty environments, such as in the textile industry. Deposits form which reduce smooth operation and, in the worst case, lead to failures. "To get to grips with this problem, we have designed the new hybrid ball bearings in such a way that they work without lubrication," explains Semsroth. Thanks to the use of the high-performance plastic xirodur B180, they allow for low-friction dry operation, which reduces susceptibility to dirt and makes maintenance superfluous. Another advantage: the outer race runs with low friction on aluminium profiles. Steel bearings usually require an additional plastic outer and are therefore more complex and expensive.

Hybrid design ensures a load capacity of up to 39kg

"In the past, many design engineers of overhead conveyors expressed the wish to switch from steel ball bearings to plastic variants from igus. In many cases, however, this was not possible as the load capacity of solid plastic bearings is too low," explains Semsroth. The most critical component of the hybrid bearing - the inner race - is therefore made of stainless steel. This is where the highest surface pressure acts. The load balls are also made of stainless steel, but of a different alloy. The cage consists of iglidur J3, a high-performance polymer with additives to improve strength and sliding properties. Thanks to this combination, the hybrid bearing permits a load capacity of 39kg. "Although metal ball bearings with a load capacity of 80 to 100kg are stronger, the new hybrid ball bearing is suitable for a wide range of applications in industry and logistics, for example in furniture construction or packaging systems." The ball bearings are now available in three variants with inner diameters of 8mm, 10mm and 12mm. There is also a version with a spherical outer race that allows for smooth operation in aluminium profiles.