Abstract: A three-ring packing set for a forged valve stem is disclosed which includes upper and lower adapter rings formed from fiber reinforced graphite tape and each having a first density and a first axial thickness, and an intermediate preform ring formed from graphite tape and having a second density that is less than the density of the upper and lower adapter rings and a second axial thickness that is less than the axial thickness of each of the adapter rings.

Abstract: A switch fitting, in particular a cock, ball cock, flap or likewise, with a switch rod for a switch member, which is rotatably and slightly tiltably guided in a switch shaft bore of a fitting housing and which has a sealing surface which is formed on a collar on the side opposed to the switch member, with a sealing ring cooperating with the sealing surface and being supported on a graduation of the switch shaft bore, and with a spring pressing the sealing surface against the sealing ring, wherein the sealing ring has essentially a fine contact with the sealing surface.

Abstract: A stem seal having first and second wiping members circumjacent a stem is disposed within a bore. A lubricant-bearing ring is disposed about the stem within the bore between the wiping members, under compression therefrom. Projections from the wiping members intrude into the lubrication ring so as to depress the central surface areas thereof. Similar projections are used to center a coil spring against one of these seal members and against an additional seal member. By forming the lubricant ring of open-cell loam or mesh construction, superior lubricant bearing capacities may be achieved.

Abstract: A valve assembly configured to maintain a seal during thermal cycling includes a valve body defining a flow passage, and a fluid control member disposed in the flow passage for controlling the flow of fluid. An actuating shaft is interconnected with the fluid control member for moving the fluid control member. A housing including an internal wall defining a shaft bore is connected to the valve body, and the actuating shaft extends through the shaft bore with the internal wall of the housing radially spaced from the actuating shaft to define a sealing cavity. A seal is located within the sealing cavity for inhibiting fluid flow between the actuating shaft and the housing. The seal includes a plurality of first surfaces and the housing defines a plurality of opposed surfaces such that sealing contact of the seal with the actuating shaft and the housing is maintained during thermal cycling.

Abstract: A seal system for an oil well head, wherein the shaft rotates about its axis to drive a progressive cavity type pump. Primary and secondary polytetrafluoroethylene seals surround a sleeve that encircles the shaft. Pressure detectors connect to the space between the seals to detect leaks past the primary seal and signal a remote repair facility. The secondary seal assumes the sealing function while repairs are scheduled.