Robust plain bearings for heavy duty use in cultivators

Lemken  needed robust plain bearings that were lubrication and maintenance-free and are able to withstand high loads during pivoting movements. The "Karat 9" is an intensive cultivator manufactured by Lemken  that can be used for shallow, medium-deep and deep cultivation, depending on the requirements and work step so using lubrication and maintenance free components not only significantly lowered their costs but reduced maintenance time as well as having an environmental impact.

Being a heavy duty agricultural piece of equipment, the need for robust, durable and reliable products within the machines was crucial.

One of the manufacturer's product areas is stubble working appliances, cultivators and short disc harrows. Today, these are primarily used for conservation tillage and stubble working. The "Karat 9" offers an intensive cultivator that penetrates between five and 30 centimetres deep into the soil, therefore optimally incorporating organic matter. During operation, there may be large stones in the path of the tractor, which must not hinder the operational process. The Karat 9 is equipped with overload elements, whereby the tines, which work in the soil during normal operation, automatically move backwards and upwards and then return to the working position. Depending on the size of the cultivator, the metal bearing solution used to move the tines had to be lubricated for up to 1 hour a day in order for the bearings to work properly. If the numerous lubrication points, depending on the working width, were not sufficiently lubricated, the resulting lack of lubrication led to considerable problems with corrosion and greatly increased wear of the bearing point, which ultimately resulted in damage to shafts and housing bores.

Thanks to the use of lubrication-free igus plastic plain bearings, the overload element now works without maintenance. The high-performance materials require no relubrication as the bearings contain solid lubricants. This helps the farmer save valuable time. Unlike metal bearings, where the lubricants cannot be distributed evenly and only the same points are stressed, plastic plain bearings can play to their strengths here. The pivoting movements cannot affect them as much and there is no danger of lubricants being displaced. Another advantage is the bearings' dry operation as no dirt can adhere to them. Their high stability and the fact that they can easily withstand the high forces in the cultivator's overload element make them significantly more reliable. Lemken also saved costs thanks to the more favourable procurement expenses and the plain bearings' increased service life.
The Karat 9 cultivator features plain bearings made from the all-rounder iglidur G, which can withstand a compressive strength of 80MPa.