Double-acting piston seals of the types KD 02 (without notches) and KD 03 (with notches) are ideally suited for use in hydraulic systems and promise stick-slip-free running as well as good dry-running properties. The media used in these applications range from mineral oil-based hydraulic liquids, environment-friendly bio-oils and water to flame-resistant hydraulic liquids and air.
While the PTFE profile ring provides dynamic sealing against the cylinder surface, the elastic O-ring ensures there is a uniform contact pressure of the PTFE profile ring onto the cylinder surface and at the same time a static sealing between profile ring and groove base.
Even at low pressures, the piston seal shows a good sealing effect due to the inherent preload of the PTFE profile ring and the contact force of the preloaded O-ring. At higher system pressures, the medium pressurizes the O-ring causing it to press the PTFE seal with enhanced force against the cylinder surface.
With different material combinations, the piston seal can be used reliably across the whole pressure, speed and temperature range.