Abstract: A method for removing and inserting a tubular frusto-conical seat (26) from the seat cavity (22) of a valve chamber (20) in a valve body (12). The tool (46) for performing the method has a laterally extending protuberance (60) on its inner end adapted to be received within a port (38) of the seat (26) for prying the seat (26) loose upon a prying action of the tool (46). An annular shoulder (56) on the tool (10) engages the outer annular surface (42) of the seat (26) for providing a pivot axis.

Abstract: A valve seat tool (46) and method for removing and inserting a tubular frusto-conical seat (26) from the seat cavity (22) of a valve chamber (20) in a valve body (12). The tool (46) has a laterally extending protuberance (60) on its inner end adapted to be received within a port (38) of the seat (26) for prying the seat (26) loose upon a prying action of the tool (46). An annular shoulder (56) on the tool (10) engages the outer annular surface (42) of the seat (26) for providing a pivot axis.

Abstract: In a valve having a valve body and a bonnet mounted on the valve body, a bonnet lock secures the bonnet against relative rotation with the valve body. The bonnet lock cooperates with a pin driven into the valve body to lock the bonnet against rotation. Unequally spaced slots formed about the lower end of the bonnet lock permit adjustment of the bonnet lock for alignment with the lock pin. A jam nut threadably mounted on the bonnet engages the bonnet lock and maintains it in position.

Abstract: An improved stem packing. In the preferred and illustrated embodiment, the packing for the stem is captured within a housing normally described as a bonnet assembly, and is axially loaded by a cooperative jam nut and bushing. They axially load the top end of the stem packing, forcing it to expand radially inwardly and outwardly to grip the stem to seal against stem and bonnet surfaces. Extrusion of packing material typically occurs. The improved version of stem packing apparatus in the preferred and illustrated embodiment is a tubular sleeve of relatively elongate lubricated plastic material having a plurality of partial circumferential parallel cuts in it, thereby decreasing the axial load required to achieve sealing. The seal material controllably expands controlled by the cuts, thereby achieving the desired internal and external seal to prevent leakage. Torque required to rotate the stem is reduced, and extrusion of the seal material is markedly reduced.