Abstract: A composition having a crosslinking compound that has the following structure (I) wherein R is OH, NH2, halide, ester, amine, ether, or amide, and x is 2-6 and A is an arene moiety having a molecular weight of less than about 10,000. A mixture including the composition and a polymer, a method for forming the mixture and a crosslinked polymer are also disclosed.

Abstract: A self contained sensing apparatus includes a housing establishing an interior compartment, the housing having a maximum thickness which is less than the size of an access portal for inserting the housing into an area for sensing. The housing includes a window extending through a principal housing surface. A sensor is provided within the housing and generally aligned with the window for sensing at least one parameter. In a preferred embodiment, the sensor is an optical sensor for sensing images through the window. A transmitter is provided within the housing and coupled with the sensor for receiving signals representative of the sensed parameter and transmitting the signals out of the housing.

Abstract: A self contained sensing apparatus includes a housing establishing an interior compartment, the housing having a maximum thickness which is less than the size of a gate opening of a semiconductor wafer processing chamber for inserting the housing into the semiconductor wafer processing chamber for sensing a parameter. The housing includes a window extending through a principal housing surface. A sensor is provided within the housing and generally aligned with the window for sensing at least one parameter. A transmitter is provided within the housing and coupled with the sensor for receiving signals representative of the sensed parameter and transmitting the signals out of the housing.

Abstract: An elastomeric composition having improved resistance to chemical attack is provided, the elastomeric composition including a perfluoroelastomer and a non-fibrillating particulate fluorographite. Also, a process for improving the processibility and resistance to chemical attack of a perfluoroelastomer is provided, in which the perfluoroelastomer is mixed with a non-fibrillating fluorocarbon particulate polymer to form a elastomeric composition which is processed at a temperature less than the melting temperature of the non-fibrillating fluorocarbon particulate polymer to disperse the fluorocarbon polymer throughout the perfluoroelastomer while maintaining the fluorocarbon polymer in particulate form. A method of making a seal which is resistant to chemical attack for preventing the leakage of a fluid between a first member and a second member is also provided.

Abstract: An elastomeric composition having improved resistance to chemical attack is provided, the elastomeric composition including a perfluoroelastomer and a non-fibrillating particulate fluorographite. Also, a process for improving the processibility and resistance to chemical attack of a perfluoroelastomer is provided, in which the perfluoroelastomer is mixed with a non-fibrillating fluorocarbon particulate polymer to form a elastomeric composition which is processed at a temperature less than the melting temperature of the non-fibrillating fluorocarbon particulate polymer to disperse the fluorocarbon polymer throughout the perfluoroelastomer while maintaining the fluorocarbon polymer in particulate form.

Abstract: A sealing assembly between first and second relatively rotatable parts, such as the parts of a tunnel boring machine, in which a flange on a first part has a radial sealing face engaged by the axial faces of inner and outer sealing rings mounted on the body portion of the second part at radially spaced locations, a bleed passage in the second body portion opening between the sealing rings and indicating any failure in the outer sealing ring.

Abstract: A seal assembly is disclosed for installation in an annular groove having inner and outer radial surfaces interconnected by an axial surface. The seal assembly is comprised of a generally annular energizer element formed of an elastomeric material and including a body portion and a generally radially extending sealing lip. The seal assembly further comprises a generally annular heel bearing element formed of a generally rigid material. Upon installation of the energizer element and heel bearing element into the annular groove, an annular void, generally triangular in cross section, is formed between the two seal elements. Upon the application of pressure at or above a predetermined pressure limit, the energizer element moves into the annular void drawing at least a portion of the sealing lip into the groove to reduce the axial width of the sealing lip contact area.

Abstract: An improved generally annular split sealing ring includes generally curved radially inner and outer surfaces and opposed first and second axial surfaces extending between the inner and outer surfaces. The sealing ring has an axially extending, radially centered axis and a cut extend therethrough from the inner radial surface to the outer radial surface to create a gap to facilitate installation and removal of the sealing ring. The cut extends through the sealing ring along a single continuous cut plane. The orientation of the cut plane is determined by establishing a first reference plane extending radially through the sealing ring and generally parallel to and through the axis. A second reference plane extends generally perpendicular to the first reference plane and midway between the first and second axial surfaces to establish a first generally radially extending reference line.

Abstract: An oil well string member has a cylindrical outer periphery having first and second cylindrical surfaces axially spaced and connected by a tapered ramp. The surfaces are radially inwardly of the outer periphery. The first surface has a smaller diameter than the second surface. A seal assembly is provided along the first surface and arranged to respond to fluid pressure for moving the assembly across the ramp to the second surface to a sealing position.

Abstract: A two-stage fluid seal assembly is provided for sealing between relatively moving parts, such as a piston and cylinder. The assembly comprises a hard-sealing, non-resilient material effective at high pressure and a resilient soft-sealing material effective at low pressures.

Abstract: A sealing ring firmly grips a movable piston, performs the normal sealing function, and when pressure is released on the piston the sealing ring pulls back on the piston so as to retract the piston. The sealing ring is designed so as to fit in a conventional seal or "O" ring groove without any modification of the groove.

Abstract: A sealing ring firmly grips a movable piston, performs the normal sealing function, and when pressure is released on the piston the sealing ring pulls back on the piston so as to retract the piston. The sealing ring is designed so as to fit in a conventional seal or "O" ring groove without any modification of the groove.

Abstract: An annular seal of resilient material is disclosed and having an axially directed groove containing a spring between two interconnected body portions. At least one of said body portions has a sealing lip projecting in a radial direction generally opposite the location of said spring. Said groove has portions spaced from the bottom and in embracing contact with opposite surfaces of said spring. Said groove bottom being a portion of an ellipse and having embracing contact with a juxtaposed portion of said spring only when the sealing lip is under a compressive load.