Abstract: A brush seal arrangement for sealing cooperation between a shaft and a surrounding member which is relatively rotatable with respect to the shaft. The brush seal includes an annular rotor disposed in surrounding relationship to the shaft and sealed with respect to the housing, and the rotor mounts thereon first and second annular bush members which are disposed in axially spaced relation and which have annular edge portions which create a frictional and sealing engagement with the shaft to nonrotatably and sealingly couple the rotor to the shaft. A passage extends through the rotor for communication with an annular region defined between the annular brushes in surrounding relationship to the shaft, and a pressurized buffer gas is supplied through the passage into the annular region.

Abstract: A gas seal construction for use on a pump to create a seal between a relatively rotatable pump shaft and housing. A flow barrier arrangement is disposed in close surrounding relationship to the shaft and cooperates with the surrounding housing axially between the seal and the pump chamber for minimizing ingress of pump liquid into the seal chamber during both static and dynamic conditions. The barrier arrangement includes an annular barrier member nonrotatably secured to the shaft and cooperating with an annular shroud which is secured to the housing. The barrier member and shroud have opposed truncated conical surfaces which define a narrow annular passage therebetween which slopes outwardly away from the seal chamber toward the pumping chamber and, at the large diameter end thereof, communicates with an annular sealing zone or dam which is defined between the relatively rotatable barrier member and housing for further restricting ingress of pumping fluid into the seal chamber.

Abstract: An improved gas seal having inboard and outboard seal units each defined by a pair of opposed and relatively rotatable seal faces, one face of each pair having appropriate grooves which communicate with a pressurized barrier gas, preferably an inert gas such as nitrogen. The inboard seal unit, at its other seal periphery, communicates with a process fluid being handled by a rotating equipment, namely a pump. Each seal unit has one of the seal rings, the nonrotating ring in the preferred embodiment, urged axially toward its opposed ring by a compact bellows which axially cooperates between the respective seal ring and a backing member. The bellows is positioned to create an isolation between the barrier and process fluids and to provide an effective diameter to provide desirable balance of pressures as imposed on the axially moving seal ring to optimize seal performance. The bellows is preferably a single convolution which is free of fixed securement to the moving seal ring.

Abstract: An improved gas seal having inboard and outboard seal units each defined by a pair of opposed and relatively rotatable seal faces, one face of each pair having appropriate grooves which communicate with a pressurized barrier gas, preferably an inert gas such as nitrogen. The inboard seal unit, at its other seal periphery, communicates with a process fluid being handled by a rotating equipment, namely a pump. Each seal unit has one of the seal rings, the nonrotating ring in the preferred embodiment, urged axially toward its opposed ring by a compact bellows which axially cooperates between the respective seal ring and a backing member. The bellows is positioned to create an isolation between the barrier and process fluids and to provide an effective diameter to provide desirable balance of pressures as imposed on the axially moving seal ring to optimize seal performance.