A grounding ring, including a substantially circular-ring-shaped hub and at least two sliding contacts, which are arranged on the outside of the hub in the radial direction, extend in the circumferential direction and, in the manufactured state of the grounding ring, are arranged adjacent to one another at a distance from one another in the circumferential direction and delimit a circumferential gap with their sides facing one another in the circumferential direction, and wherein the circumferential gap is substantially bridged during the intended use of the grounding ring by the mutually facing and mutually non-overlapping sides.

A seal assembly includes a seal disposed about a shaft and having an annular body with a radial sealing surface and an inner circumferential sealing surface engageable with the shaft. A housing is disposed about the shaft and has a first inner circumferential surface defining a first annular chamber about the shaft, the seal being disposed within the first annular chamber, a second inner circumferential surface spaced radially inwardly from the first inner circumferential surface and spaced from the outer surface of the shaft by a radial clearance so as to define a second annular chamber. A radial seal contact surface extends between the first and second inner circumferential surfaces and is sealingly engageable by the sealing surface of the seal to prevent flow between the two chambers, and circumferential pressure groove(s) are formed in the seal contact surface and are fluidly coupled with the first chamber.

A seal assembly includes a seal disposed about a shaft and having an annular body with a radial sealing surface and an inner circumferential sealing surface engageable with the shaft. A housing is disposed about the shaft and has a first inner circumferential surface defining a first annular chamber about the shaft, the seal being disposed within the first annular chamber, a second inner circumferential surface spaced radially inwardly from the first inner circumferential surface and spaced from the outer surface of the shaft by a radial clearance so as to define a second annular chamber. A radial seal contact surface extends between the first and second inner circumferential surfaces and is sealingly engageable by the sealing surface of the seal to prevent flow between the two chambers, and circumferential pressure groove(s) are formed in the seal contact surface and are fluidly coupled with the first chamber.

A seal assembly includes an outer annular case disposed within and coupled with a rotatable outer member to be angularly displace about a central axis. An annular flexible seal is disposed within and coupled with the case to angularly displace about the central axis when the outer member rotates about the axis. The flexible seal has elastomeric sealing lip(s) engageable with an outer circumferential surface of the shaft or of a sleeve disposed about the shaft. An annular inner rigid seal is disposed within the outer case and has an inner end coupled with the shaft or the sleeve, the flexible seal being radially displaceable with respect to the inner rigid seal. An outer annular rigid seal is disposed about the inner seal and has an inner end sealing against the inner rigid seal. A biasing member biases the outer rigid seal against the inner rigid seal.

There is provided a vertical sealing device capable of preventing foreign matter from entering a seal portion from the outside of a machine. In a vertical sealing device with a seal portion axially sealing a rotating shaft provided in a machine and extending in a vertical direction, an annular collar portion which extends in an outward radial direction from a radial gap between a rotational side element and a stationary side element is provided in the rotational side element so as to be located on an outside of the machine with relation to the seal portion.

A rotary positive displacement pump comprising a pair of forwardly-positioned sealing arrangements and a pair of forwardly-positioned sleeves are received within a cavity providing for easy maintenance of the pump when the seals need to serviced. Each of the sealing arrangement includes a dynamic seal and a static seal. The dynamic seal abuts a corresponding sleeve and hub while a static seal is established between the corresponding sleeve and rotor.

A rotating leaf spring seal is disclosed. In various embodiments, the rotating leaf spring seal includes a first annular ring configured for positioning against a support structure; a hook section having an outer surface configured for sealing engagement with a tie shaft and an inner surface configured for receiving a hold down ring; and a spring section disposed between the first annular ring and the hook section.

A seal element for an annular control device includes an elastomer seal sleeve having an annular opening therein and arranged to be radially compressed to contact an exterior of a pipe disposed within the elastomer seal element. The elastomer seal sleeve comprises at least one of a wear resistant material disposed on an interior surface of the annular opening and a lubricant channel on the interior surface.

An end face mechanical seal for a high pressure, compressible fluid includes metal or ceramic seal faces separated by a seal gap having at least one supersonic region that accelerates the fluid in the leakage direction, producing a shockwave that reduces fluid pressure to significantly reduce viscous heating and gap length. A choke width of the seal gap formed between the converging and diverging segments of the first supersonic region is between 50 and 200 micro-inches, and upper and lower boundaries thereof are flat, with combined slopes of less than 10 degrees. A total length of all of the supersonic regions is less than 0.1 inches. A non-supersonic region can further reduce fluid pressure by inducing viscous stresses. The seal can be configured axially or radially, and can be used as a pre-conditioner in combination with a conventional downstream mechanical fluid seal.

An end face mechanical seal for a high pressure, compressible fluid includes metal or ceramic seal faces separated by a seal gap having at least one supersonic region that accelerates the fluid in the leakage direction, producing a shockwave that reduces fluid pressure to significantly reduce viscous heating and gap length. A choke width of the seal gap formed between the converging and diverging segments of the first supersonic region is between 50 and 200 micro-inches, and upper and lower boundaries thereof are flat, with combined slopes of less than 10 degrees. A total length of all of the supersonic regions is less than 0.1 inches. A non-supersonic region can further reduce fluid pressure by inducing viscous stresses. The seal can be configured axially or radially, and can be used as a pre-conditioner in combination with a conventional downstream mechanical fluid seal.