Busak+Shamban develop an innovative seal configuration with unique design of Wear Ring. This has proved to meet all performance requirements and save money in telescopic hydraulic cylinders intipper trucks.
Tipper trucks are operated using telescopic cylinders with three, four, five or more steps. Of a compact design, the wall thickness of the cylinders is thin and they have a short guiding length, the
guiding achieved either by nitrading the machined steel rod or by installation of Wear Rings.
International seal developer and manufacturer Busak+Shamban have long been involved in the hydraulics industry and decided to investigate the optimum sealing and Wear Ring arrangement for this
In addition to fitting into an extremely narrow installation space, the seal and Wear Ring combination also needed to work at a pressure of 21MPa (3045 psi, 210 bar). It had to retain integrity at
temperatures from -40°C (-40°F) up to +110°C (230°F), operate at speeds reaching 0.5 m/sec (20 inch/sec) and be resistant to mineral oil based hydraulic fluids and bio oils. Excellent static and
dynamic sealing had to be maintained, even when the cylinders were subject to severe vibration caused by the truck driving on rough surfaces.
Busak+Shamban engineers came up with numerous proposals, which they tested in a virtual environment using computer simulation techniques, including advanced FEA modeling. The optimum design proved to be a combination of seal, scraper and Wear Ring specific to these telescopic applications.
The recommended U-Cup seal and Scraper RTL or RTI are both manufactured from Zurcon®, the Busak+Shamban proprietary polyurethane based material specially developed for sealing elements. This material has excellent friction characteristics, exceptional temperature performance and almost universal chemical resistance.
The unique Wear Ring is manufactured from HiMOD® HM061, an engineered thermoplastic. Its special L-shape met all the performance requirements and allowed the dimension of the steel tube to be reduced, lowering overall manufacturing costs.