Polymer plain bearings, special parts that compensate tolerances, in heavy-duty agricultural equipment construction

Application data

What was needed: a reliable storage for the prongs
Manufacturing process: injection moulding
Requirements: reduction of assembly costs through wear-resistant parts and freedom from maintenance
Material: iglidur® G
Industry: agricultural machinery/agricultural technology
Success for the customer: €80,000 savings per year

Robust special bearing for hay swathers

The customer's agricultural equipment manufacturer FELLA-Werke GmbH are large agricultural enterprises, machinery contractors; machinery rings and also farmers with only a few acres of land. "As we are not aware of every detail of the conditions prevailing in every case, we have to pay attention to the robustness of the machines we design without losing sight of the costs involved in manufacturing", says Kohl. "This means that the choice of the components deployed is equally as important. “

FELLA has been designing implements for tractors for more than 90 years. These include mowers, hay rakes and swathers. The swather works by using eight, ten or twelve tine arms to rake together stalk material that has already been mown or spread out to form a swathe.
 
All swathers made by this supplier work exclusively using rotary technology, i.e. exploit the benefit of high area performance. "The bearings on the prongs are a part of the complex control system are the most important function of the machine," clarifies the design manager. "If these get damaged, the rotary rake stops working. And this must not happen at any time during the harvest. Even at the test stage we recognised that we needed an anti-rotation feature," recalls designer Dipl. Ing. (FH) Jürgen Riedel.

It quickly became apparent to the company that plastic could be used to cut costs. "In the beginning, we had plastic bushings turned ourselves and later had them injection moulded. But the results were not satisfactory because the choice of material wasn't right," Jürgen Riedel recalls. "As a mechanical engineering company, we decided that we needed to look for a plastics expert. “
 
The extensive igus® product range, which includes standard and customised parts, quickly provided a suitable solution. Having been tested thousands of times under everyday conditions in the igus® laboratory, the high level of abrasion resistance and the dry-operation properties of the polymer plain bearings immediately revealed their worth in real-life agricultural applications.