US 8,814,139 B2 · Anti-extrusion packing support

Abstract

A seal arrangement for providing a fluid seal of an annulus between two conforming surfaces such as a stem and a bore. The seal arrangement may include a pair of packing support rings. Preferably, two pairs of the packing support rings are used in order to provide double ended or two sided axial support for the packing. The first and second support rings support a load on the packing during normal or rated temperature use, with preferably an interference fit with the stem to resist extrusion of the packing along the stem. The support rings may be nested together and comprises different materials. For example, one support ring may comprise metal and the other support ring comprise a softer material such as a polymer or elastomer. An example of a packing material is a fire resistant material. The metal support ring may be used to maintain load on the fire resistant packing in the event that the other support ring has been destroyed by fire or other cataclysmic event.

Claims20

Dependent claims

A stem seal for a fluid containing device of the type having a stem disposed in a bore, the seal arrangement comprising:

a stem comprising an outer surface and a bore comprising an inner surface, said stem being sized to be received within said bore, said bore inner surface being complementary shaped to said stem outer surface,
a packing disposed about a portion of said stem outer surface, said packing providing a fluid seal for an annulus between said stem outer surface and said bore inner surface,
a first pair of support rings disposed adjacent a first axial end of said packing and a second pair of support rings disposed adjacent a second axial end of said packing,
each said pair of support rings comprising a metal ring for applying a compressive load on said packing and an anti-extrusion ring being in radial compression against said stem outer surface and that resists extrusion of said packing
said metal ring of said first pair of support rings being in direct contact with said first axial end of said packing and said metal ring of said second pair of support rings being in direct contact with said second axial end of said packing.

2 more elements

Dependencies are inferred from the claim text.

Anti-extrusion packing support

Life of this patent

Anti-extrusion packing support

Life of this patent

Abstract

Claims20