Views
6 years ago

MDA Technologies 5/2014

MDA Technologies 5/2014

Robust, precise, and

Robust, precise, and powerful: bearing solutions for agricultural machinery Dipl.-Ing. Peter Pospiech Agricultural engineering spans a broad range of machinery, systems, and equipment: from cultivation machines and tractors, tedders and balers, to huge harvest equipment items such as choppers, combine harvesters, and root-crop harvesters. But no matter how different these machines might be, the operating conditions are always harsh this also applies for the bearings in use. Author: Dipl.-Ing. Peter Pospiech is freelance editor at PPM News Service Pospiech Maritim in Rhauderfehn The biggest challenges are both the sand and dust that are hardest on the bearing seal and the moisture that affects the bearings. It is here that the designer has to overcome big challenges. In addition to plant residue, this type of machinery also has to 01 Four-point contact ball bearing for seed disks with high tilting rigidity handle sap from the plants that attacks seals with its acidic properties. Once the seal is damaged, the penetrating contamination destroys the bearing in a short time. Constant vibrations and jarring shocks make for constant strain in all seasons and weather conditions. Similarly, cultivation machines that prepare the field for planting seeds also require extremely robust bearing supports. An example of these are plow disks, whose slanted position results in not only radial forces, but also shear forces and side loads. The bearing types used have to transfer just these kinds of external load combinations. In addition, the high levels of precision required for efficient sowing must not be underestimated. Early involvement with innovations Under the brand names of INA and FAG, Schaeffler produces standard bearings for agricultural machinery, perfected through customer-specific solutions. These include components for cultivating and sowing machines, for tractor engines, transmissions, and chassis, as well as harvesters. Their primary customers are OEMs around the world. For this reason, the experts at Schaeffler get involved early on in new machinery developments and can therefore react to related demands, coming up with the right solutions and allowing them to influence the products. Field service engineers on site regularly communicate with the customer, in this way guaranteeing early involvement even with innovations. Global support Schaeffler specialists have the necessary system understanding at their fingertips to integrate a component or a module into an overall system. This may involve a catalog product or a solution especially developed 34 MDA Technologies 5/2014

Machine elements FAG tapered roller bearings for hauler transmissions for the customer. “In order to offer the best technical solution, our engineers need to understand the system and the demands placed on it in agricultural engineering. Only in this way can we obtain the best possible success for our customers in the drive train or the cultivating equipment. We are getting more and more involved in the field of mechatronics – our expertise in the area of sensors is just the beginning. Field service engineers and the Schaeffler Technology Centers located across the globe are the first on-site contact persons for the customer. Industry-specific application technology, e.g. the engineering hubs for agricultural engineering in India, America, and Europe, is interconnected around the world through the Global Technology Network. Schaeffler’s expert knowledge is therefore available on a global scale in cooperation with the central R&D areas. In this way, we can make our product, application, and service expertise optimally useful to our customers,” says Eduard Beresch, manager application engineering agricultural engineering off highway. Four-point contact bearing for seed disks Depending on its width, a sowing machine has over 100 seed disk bearings installed inside. It is unthinkable to have to relubricate these bearings during harvest season. Nevertheless, the environment is and continues to be a challenge: Fine, abrasive particles of dust, aggressive acidic silage sap, stony and heavy loam soils – a standard bearing will not hold up here. Instead, a special bearing solution with a particularly effective sealing concept is required. Schaeffler has developed its own compact INA four-point contact bearing for such seed disks. The four-point contact ball bearing for seed disks stands out with four advantages: It has a high tilting rigidity and load-carrying capacity, operating almost without backlash. These advantages are mainly due to the polished ground steel raceways of the outer and inner ring that absorb the operating forces and torques without difficulty. In addition, the bearing has an optimized sealing concept that ensures the constant operation of the bearing position with the maximum amount of grease. Bearings for pressure wheels in sowing machines INA bearings are also used for pressure wheels in sowing machines: Double row angular contact ball bearings with integrated pins reduce the number of components for the customer. This simplifies and abridges the assembly process. The efficient and watertight radial shaft seal with its spring preload is already integrated in the bearing, allowing the pressure wheel to function reliably during operation. Other pluses: Due to the integrated seal, with a preloaded spring ensuring the sealing action even when worn, the bearing holds up much lon- MDA Technologies 5/2014 35

E-PAPER KIOSK: