An embodiment includes a gate valve comprising: a valve body including a cavity coupled to a channel having proximal and distal portions; a gate to seal and unseal the channel; proximal and distal seats adjacent the gate; wherein (a) the proximal seat traverses towards the gate and stops at a first position when the gate is closing and the proximal channel portion is more highly pressurized than the cavity, and (b) the distal seat slides away from the gate and stops at a second position when the gate is closing and the cavity is more heavily pressurized than the distal channel portion. Other embodiments are described herein.

An embodiment includes a gate valve comprising: a valve body including a cavity coupled to a channel having proximal and distal portions; a gate to seal and unseal the channel; proximal and distal seats adjacent the gate; wherein (a) the proximal seat traverses towards the gate and stops at a first position when the gate is closing and the proximal channel portion is more highly pressurized than the cavity, and (b) the distal seat slides away from the gate and stops at a second position when the gate is closing and the cavity is more heavily pressurized than the distal channel portion. Other embodiments are described herein.

An embodiment includes a gate valve comprising: a valve body including a cavity coupled to a channel having proximal and distal portions; a gate to seal and unseal the channel; proximal and distal seats adjacent the gate; wherein (a) the proximal seat traverses towards the gate and stops at a first position when the gate is closing and the proximal channel portion is more highly pressurized than the cavity, and (b) the distal seat slides away from the gate and stops at a second position when the gate is closing and the cavity is more heavily pressurized than the distal channel portion. Other embodiments are described herein.

A seal including a jacket including an annular body defining a central axis and a recess extending into the annular body concentric to the central axis, where the jacket includes at least 30 wt % of a PTFE and at least 10 wt % of a filler material, and where the filler material includes a boron-containing material, a nitrogen-containing material, a titanium-containing material, a silicon-containing material, a carbon fiber, a glass fiber, or a combination thereof; and an energizing element disposed in the recess, where the energizing element includes a gap-less spring.

Systems and methods include providing an annular seal stack for an assembly. The seal stack assembly is disposed between a probe and a housing of the assembly and configured to provide a radial seal between the probe and the housing. The seal stack assembly includes a first metallic seal, a second metallic seal, and a wiper assembly disposed between the first metallic seal and the second metallic seal. The wiper assembly includes a first wiper housing component having a tapered inner surface, a second wiper housing component having a tapered inner surface opposite the tapered inner surface of the first wiper housing component, and a wiper disposed between the first wiper housing component and the second wiper housing component.

Spring energized seal assemblies each with one or two sealing elements and a canted coil spring located in a spring cavity of the sealing element or of the two sealing elements to bias an inner flange and an outer flange of the respective spring cavity away from one another. The canted coil springs can have un-conventional coil shapes with one or more straight coil segments and/or with curved connecting ends. The coils can have dimples to provide multiple biasing points. The coils can have loops. The canted coil springs with un-conventional coil shapes can be used to improve spring loading on a sealing element.

Spring energized seal assemblies each with one or two sealing elements and a canted coil spring located in a spring cavity of the sealing element or of the two sealing elements to bias an inner flange and an outer flange of the respective spring cavity away from one another. The canted coil springs can have un-conventional coil shapes with one or more straight coil segments and/or with curved connecting ends. The coils can have dimples to provide multiple biasing points. The coils can have loops. The canted coil springs with un-conventional coil shapes can be used to improve spring loading on a sealing element.

A sealing device includes: a housing; a seal ring configured to be axially displaceably inserted along an inner circumference of the housing, the seal ring including a front-end surface and a rear-end surface which defines packing mounting space; a packing configured to establish sealing between the housing and the seal ring, the packing being disposed in the packing mounting space; and spring means disposed on the rear-end surface side of the seal ring to elastically bias the seal ring toward the front-end surface side.

The present invention relates to the field of push rods, in particular to a waterproof and dustproof electric push rod, where a waterproof and dustproof module includes a single-lip oil seal, a first anti-swing ring, a piston oil seal and a second anti-swing ring, which are arranged in sequence in a retraction direction of an inner tube. When the inner tube retracts, since inner rings of the single-lip oil seal, the first anti-swing ring, the piston oil seal and the second anti-swing ring are tightly attached to an outer sidewall of the inner tube, the single-lip oil seal plays a role in scraping off dirt (dust, silts, etc.) on the surface of the inner tube, and the internal piston oil seal can be waterproof and dustproof.

A sealing system includes: a first seal including at least one first seal lip sealing against a first surface and a second surface and having a first cavity filled with a first energizer forcing the at least one first seal lip against the first surface and the second surface, the first cavity facing a first pressure region; and a second seal spaced from the first seal and having at least one second seal lip sealing against the first surface and the second surface, the second seal including a second cavity filled with a second energizer forcing the at least one second seal lip against the first surface and the second surface to separate a second pressure region from a third pressure region. The at least one second seal lip is configured to deform such that fluid pressures in the first, second, and third pressure regions equalize.