Abstract: A seal system is disclosed for sealing a housing and rotatable shaft against leakage of high vapor-pressure liquids. The method of sealing contemplates phase change of the liquefied hydrocarbon fluid across a first module. The gas so formed is contained by a second seal module which operates as a dry running gas seal. The seal system has plural, axially spaced spiral-groove seal modules mounted between the shaft and housing. Each seal module has a primary ring affixed to the housing and a mating ring affixed for rotation with the shaft and the modules define an intermediate cavity. The rings have opposed, radially extending faces, one of which has a plurality of downstream pumping spiral grooves extending from one circumference. The grooves of the grooved ring of the upstream module are of a depth not to exceed about 100 micro-inches. In a preferred form, the depth of the grooves of the upstream module do not exceed 50 micro-inches.
June 10, 1987
Date of Patent:
December 26, 1989
John Crane-Houdaille, Inc.
Donald E. Amundson, Jon B. Hamaker, Glenn G. Pecht, Josef Sedy
Abstract: An improved drive for a banded sealing ring or washer in a rotary mechanical seal. The washer, usually a ceramic washer, is provided with an annular band surrounding its outer periphery which includes an outwardly extending flange. The seal includes a sleeve mounted on a rotatable shaft of a pump, which houses the washer in coaxial relation. It further includes a flange extending radially, which defines means in contact with the band of the washer, such that driving engagement is effected between the sleeve flange and the washer band and the washer is caused to rotate with the sleeve.
Abstract: A mechanical seal for use between a housing and a rotatable shaft supported by the housing, having adjacent annular primary and mating sealing rings, each ring having a generally radial sealing face. Means seals and holds the first sealing ring nonrotatably relative to the housing, and means seals and holds the second sealing ring to rotate with the shaft. One sealing ring is movable axially of the shaft, and springs urge this one ring toward the other sealing ring, which is axially fixed relative to the shaft. The axially moveable seal ring is centered coaxially with respect to the axis of the seal ring through engagement of a centering element which is centered relative to the shaft and which engages the axially moveable sealing ring to center it relative to the shaft. The centering element engages the axially moveable sealing ring to effect such centering at the periphery of the axially moveable ring exposed to the pressurized fluid to be sealed.
Abstract: A rotary mechanical seal with metal bellows having reinforced weld joints. The bellows is formed of a plurality of adjacent annular discs or diaphragms having inner and outer circumferences welded together. A plurality of annular reinforcing rings are provided, each being associated with the welded joint at one circumference of the diaphragms. The associated rings and the circumferences define a weld area. The presence of the reinforcing rings allows for larger and stronger welds along the associated circumferences, which increases the capacity of the seal to withstand operating pressures.
Abstract: A package seal particularly suited to pumps or other applications having a drive shaft which terminates internally of a housing at its connection to the impeller or fluid working element. In such an apparatus partial disassembly of the components provides access to the free end of the drive shaft. The package seal has an outer member adapted to be disposed coaxially on the rotatable shaft and pass through the housing bore. The outer member includes a mounting flange adapted to be secured in the interior of the housing and a cylindrical body adapted to extend axially along the rotatable shaft from the seal flange to the exterior of the housing. The cylindrical body houses the seal components which provide a fluid tight seal between the housing and shaft.
Abstract: An apparatus and method utilizing pressurized air discharged through nozzles to segregate a mixture of elements having either different geometrical characteristics or different masses. The mixture is placed in a container having a conveyor track, and is forced to move along the track, across a primary nozzle which forms the mixture into a single layer. The mixture then moves across a blow-off nozzle which propels one set of elements off the track and out of the container while the other remains within the container. A two stage separation may be used to optimize efficiency.
Abstract: A safety seal for a shaft passing through a housing. The seal is normally maintained in a non-sealing relationship to the shaft, but may be actuated during emergency conditions by levers. The seal includes an annular, split housing having a radially extending compartment which contains at least two seal members which are held together by a bias to define a seal annulus. The seal members are radially contracted into sealing engagement and expanded to a non-sealing position by cams or levers mounted in the seal members.
Abstract: A seal for high pressure, large diameter applications wherein three factors, each individually known in the prior art, are combined to provide a seal which is capable of operating in such applications. These factors are (1) a ratio of face width to the inner radius of the face in the range of 0.085 to 0.30; (2) hydrodynamic lift-off pads; and (3) controlled negative rotation of the sealing rings.
Abstract: A symmetrical package seal containing two balanced end face seals, the stationary components being adapted for use with shafts of different sizes. In addition, the package seal has means for centering the rotating components relative to the stationary components, for aligning the sealing faces parallel contact, and for bleeding fluid from the chamber formed by the end face seals.