Extra-robust plain bearings in track vehicle

Profile

Application area: Bearing points of the oscillating axles and the tensioning axle on the track vehicle
Industry: Commercial vehicles, construction machinery
Customer requirement: Failure-free bearings that are unaffected by mud, sludge and bog
Solution from igus: igutex TX1 plain bearing

Kässbohrer Geländefahrzeug AG received the golden manus for this application with igus plain bearings in 2021.

Kässbohrer Geländefahrzeug AG, based in Laupheim, developed the PowerBully tracked vehicle to transport drill assemblies, cranes, lifting platforms, and excavators through tough terrain. All components must be absolutely reliable and able to handle trips through mud and mire. There must be no failures, since the nearest road is often kilometres away.

The same applies to plain bearings in the chassis. Despite extensive sealing, dirt still sometimes reaches the bearing points. If this causes the bearings to seize, the vehicle could throw a track. To prevent that, the vehicle manufacturers use igutex TX1 plain bearing bushings on the four oscillating axles and the tensioning axle. igus manufactured and tested the bushings in unprecedented dimensions specifically for Kässbohrer Geländefahrzeug AG.

In search of the right material

"The positive experiences with igus plain bearings in other projects prompted me to approach Reiner Nusser at igus in May 2020," says Marius Holder. "We set up a trial test with three different igus materials, a metallic bearing, and the competitor turned bearing that had previously been used and did a long-term test under real conditions on the Kässbohrer shaft," says Nusser, Technical Sales Consultant at igus GmbH.

"The igutex TX1 turned out to be the optimal material for the PowerBully." The tests were performed on the standard heavy-load pivoting test rigs in igus' 3,800-square-metre in-house laboratory in Cologne. To determine the wear rate, igus used an outside micrometre to measure the bearing's inner diameter before and after the test. The test shows the TX1 service life is eight times that of the previous plain bearing. The turned plastic bearing has the highest dry wear rate at about 832µm/km, while the iglidur Q2 has the lowest at about 73.5µm/km. Lubricated, the metallic bearing exhibits the highest wear rate (about 199µm/km), the igutex TX1 the lowest (about 70 µm/km).