Ram piston and rod seal - has highly elastic, sealing ring sliding dry at corner nearest pressure chamber

摘要

The ram piston and rod seal has a ring of non-metallic material and rectangular section mounted in a groove shallower on the side nearest the working chamber. The min. distance from the base of the groove to the surface of the complementary component is less than the ring thickness in the radial direction. The sealing ring is of solid and highly elastic material, and the depth of the groove is less than the radial width of the ring by an amt. sufficient to cause it, under high partial pressure, to slide dry at the level of its corner nearest the pressure chamber. Between the ring and the side of the groove furthese from the pressure chamber, and at right angles to the cylinder axis, is a ring of distorting and non-self-lubricating plastics, contg. a high proportion of MoS2.