O-ring seal GKD series

bronzepolyurethanePTFE

The Hunger compact slide ring seal type GKD is used to seal and guide pistons on double-acting hydraulic cylinders. In standard form it is suitable for use with all mineral oils. The GKD consists of 4 parts, an elastic inner ring of PUR, a slide ring of abrasion-resistant PTFE-Bronze compound and two bearing rings of a pressure-resistant POM-PTFE-Bronze compound. The Hunger bearing rings make contact with the cylinder wall; there is no metallic contact between the piston and the cylinder body. The internal elastic ring energises the slide ring to press it against the cylinder wall providing a sealing function at zero pressure. The onset of pressure compresses the elastic ring increasing the radial forces acting on the slide ring, thereby increasing the sealing effect. Like the slide ring, me two beanng rings aiso s« on the olastic ring The pressure-mduced compression ot the internai ring forces the two beanng rings, and the slide ring, agamst the cylinder wall so that there is zéro clearance befween bearing rings and cylinder wal Even rf me cylnder tube expands undec pressure the seal will adapt to the radiai deformation maintaining both zéro gap and the seatng functon. When combmed wtth a surface finish Rt 0.1 - 0.3 pm of the cylinder tube, minimum friction is achieved The seal has an excellent efficiency with no stick-slip effect due to stiction.