Y-pattern piston check valve, piston valve assembly for a Y-pattern piston check valve, and method

摘要

A valve that includes a valve body in which a valve piston is disposed. The valve piston has a disc and an elongate stem that is reciprocably carried by a valve guide. The valve guide is part of an assembly that includes an cap that is attached to a Y-pattern valve body. The valve body has a valve seat that preferably is an integral hard seat and the disc has a sealing surface that preferably is a hard surface. Where operation independent of the effects of gravity is desired, a biasing element, preferably a coil spring captured in compression, is disposed in communication with the valve guide and the stem of the piston. A tolerance is provided between the stem and guide that permits angular and lateral adjustment of the disc during closing that compensates for mislocation and/or misalignment between the cap and valve body.