Gate valve

A packingless gate valve assembly comprising two body housing members having coaxial through passages, means securing said housing members together in end to end relation with means therebetween to define a relatively narrow transverse gate chamber, annular sleeve units lining each of said passages, each of said sleeve units extending into said chamber in the form of annular resilient lips adapted to sealingly engage each other under compression in the open position of said valve, and an imperforate gate slidable through said chamber between a valve open position where it does not block fluid flow through said passages and a valve closed position wherein it is interposed between said sealing lips, each of said sleeve units comprising an axially compressible annular body of elastomeric material, and there being an encircling thin stiffening band of harder material bonded around the outer periphery of each body at the gate engaging end.

In a gate valve assembly, two hollow housing members having coaxial cylindrical passages rigidly secured together end to end with axial spacer means between them defining a relatively narrow transverse gate receiving and guiding space disposed normal to said passages, sleeve units comprising annular bodies of greater axial length than said space lining each of said passages and having at one end annular resilient end lips that in the valve open position extend through said space into sealing engagement with each other, a reinforcing ring within each of said sleeves radially outwardly of its associated lip and providing a gate engaging and guiding surface on the sleeve end, each of said lips projecting axially beyond its associated ring, a gate member having an imperforate portion slidable in said space between a valve closed position wherein it blocks flow through said valve and a valve open position wherein it permits unobstructed flow through said valve, said lips being sufficiently resilient to permit sliding movement of the gate member between said positions and being compressed in resilient sealing engagement with sides of said gate member in the valve closed position.

A sleeve subassembly for a gate valve passage comprising an annular body of resilient material having an annular passage engaging outer periphery and an end that is to be adjacent the gate provided with a reinforcing and gate guiding ring in the form of a shaped annulus of thin wear resistant material consisting mainly of a peripheral band section extending around and comprising an effective continuation of the outer periphery of the sleeve body and a flat integral radial section extending inwardly over said end of the body so as to be first engaged by a gate moving to valve closed position, and an integral annular seal lip on said body end disposed radially inwardly of and projecting axially beyond said ring.

A sleeve unit for a gate valve comprising an annular body of resilient material formed at one end with an integral axially projecting annular compressible sealing lip and at its other end with an external integral radial flange, and a hard reinforcing and gate guiding ring bonded around said body at its said one end and extending over said end to provide a gate engaging end surface on said unit.

A packingless gate valve assembly comprising two body housing members having coaxial through passages, means securing said housing members together in end to end relation with means therebetween to define a relatively narrow transverse gate chamber, annular sealing sleeve units lining each of said passages, each of said sealing sleeve units being a unitary axially compressible annular body, each of said sleeve units extending into said chamber in the form of annular resilient lips adapted to sealingly engage each other under compression in the open position of said valve, an imperforate gate slidable through said chamber between a valve open position where it does not block fluid flow through said passages and a valve closed position wherein it is interposed between said sealing lips, and means for securing the end of each said sleeve that is longitudinally remote from said chamber to a body housing member, said securing means comprising a unitary radial flange on said sleeve clamped upon the associated body housing member.