Busak+Shamban have used advanced sealing design to engineer the Zurcon® U-Cup RU9 and in tests it has proved to have better performance than standard U-Cups. This innovative seal, which is manufactured from a proprietary material and includes patented technology, is able to give longer service life in rod seal applications.
In mobile and stationary hydraulic applications, rod seals are exposed to high pressure and friction for extended periods. To achieve a long service life seals must be wear and extrusion resistant, compatible to aggressive media, have a wide operating temperature range and demonstrate low friction capabilities. In addition, seals need compact installation dimensions and should ease assembly. Zurcon® U-Cup RU9 meets all these criteria and in tests is proven to out-perform standard U-Cups.
Zurcon® U-Cup RU9 was tested alongside standard U-Cups against all the main operating criteria for U-Cups: leakage, friction forces, level of lubricating oil and extrusion, with the last three measured over a range of pressures. In all of these tests and at all pressures Zurcon® U-Cup RU9 performed significantly better than standard U-Cups.
The superior performance of Zurcon® U-Cup RU9 is partly due to one of its unique features. When the system pressure is higher, the contact surface between the Zurcon® U-Cup RU9 and the piston rod becomes larger. The seal deforms to such an extent that its entire friction generating inside surface is in contact with the piston rod, improving the pressure distribution on the rod. The resulting tribological benefits (the effect of friction, lubrication, and wear of interacting surfaces) enhance the friction characteristics of the seal.
Another contributory factor is the unique patented microstructure of Zurcon® U-Cup RU9, where sliding surfaces in the seal are combined with back-pumping channels. In back-pumping technology, on the forward stroke of the shaft, an oil lubricating film is distributed under the seal. On the return stroke the oil is back-pumped into the system, preventing leakage. This extends seal life by reducing dynamic friction and breakaway force, even after pro-longed periods of rest.
The Zurcon® U-Cup RU9 is manufactured from the Busak+Shamban proprietary polyurethane material specially engineered for production of sealing elements. This gives high wear resistance, low compression set, has a wide operating temperature range and almost universal media compatibility.