Provided herein, is a valve stem seal assembly having an elastomeric sealing element, a symmetrical retainer and a valve guide. The retainer has first portion, a second portion, a continuous stop formed between the first portion and the second portion, an inner surface and an outer surface. The valve guide has a top surface in contact with the elastomeric sealing element and a side surface in contact with the inner surface of the second portion of the retainer. The stop of the retainer projects radially inward and the retainer is symmetrical.

Provided herein, is a valve stem seal assembly having an elastomeric sealing element, a symmetrical retainer and a valve guide. The retainer has first portion, a second portion, a continuous stop formed between the first portion and the second portion, an inner surface and an outer surface. The valve guide has a top surface in contact with the elastomeric sealing element and a side surface in contact with the inner surface of the second portion of the retainer. The stop of the retainer projects radially inward and the retainer is symmetrical.

A valve and stem sealing assembly capable of preventing leakage under demanding environmental and operating conditions. The valve comprises a body and bonnet secured together to house a flow-element, stem, and stem sealing assembly. The body may contain a body joint encapsulated within its liner. The flow-element is positioned between a first port and second port on the valve. The body and bonnet may be configured to eliminate rotational forces from being translated to the bonnet. The stem sealing assembly comprises a primary seal, primary shaft insert, spacer, and force transmitting member. The stem sealing assembly may also comprise a secondary seal and secondary shaft insert. The stem seal assembly is substantially adjacent to the stem, and configured to fit within an annular space or cavity between the stem and the first body half, second body half, and bonnet. The valve may also include a leak detection port.

Provided herein, is a valve stem seal assembly having an elastomeric sealing element, a symmetrical retainer and a valve guide. The retainer has first portion, a second portion, a continuous stop formed between the first portion and the second portion, an inner surface and an outer surface. The valve guide has a top surface in contact with the elastomeric sealing element and a side surface in contact with the inner surface of the second portion of the retainer. The stop of the retainer projects radially inward and the retainer is symmetrical.

Provided herein, is a valve stem seal assembly having an elastomeric sealing element, a symmetrical retainer and a valve guide. The retainer has first portion, a second portion, a continuous stop formed between the first portion and the second portion, an inner surface and an outer surface. The valve guide has a top surface in contact with the elastomeric sealing element and a side surface in contact with the inner surface of the second portion of the retainer. The stop of the retainer projects radially inward and the retainer is symmetrical.

A valve stem packing assembly can seal a valve stem to a valve body having a body cavity. The packing assembly includes a packing ring circumscribing the valve stem within a stem opening extending axially through the valve body. A primary dynamic seal is positioned to seal a dynamic leak path between the packing ring and the valve stem. A secondary dynamic seal is spaced axially apart and functionally independent from the primary dynamic seal and positioned to redundantly seal the dynamic leak path. A primary static seal is positioned to seal a static leak path between the packing ring and the valve body. A secondary static seal is spaced axially apart and functionally independent from the primary static seal and positioned to redundantly seal the static leak path.

A valve stem packing assembly can seal a valve stem to a valve body having a body cavity. The packing assembly includes a packing ring circumscribing the valve stem within a stem opening extending axially through the valve body. A primary dynamic seal is positioned to seal a dynamic leak path between the packing ring and the valve stem. A secondary dynamic seal is spaced axially apart and functionally independent from the primary dynamic seal and positioned to redundantly seal the dynamic leak path. A primary static seal is positioned to seal a static leak path between the packing ring and the valve body. A secondary static seal is spaced axially apart and functionally independent from the primary static seal and positioned to redundantly seal the static leak path.

A gate valve for use in oil field applications and including a seat seal assembly. The seat seal assembly includes primary, secondary, and tertiary seals for sealing the space between the seat rings and the valve body. The provision of multiple seals in the seat seal assembly provides redundancy that allows for maintenance of the seal between the components even if one or two of the individual seals fail.

A gate valve for use in oil field applications and including a seat seal assembly. The seat seal assembly includes primary, secondary, and tertiary seals for sealing the space between the seat rings and the valve body. The provision of multiple seals in the seat seal assembly provides redundancy that allows for maintenance of the seal between the components even if one or two of the individual seals fail.

A valve device includes: a seal member that is slidably in close contact with an outer peripheral surface of a rotation shaft; and an annular attachment ring that attaches the seal member to a housing. The seal member has a first-side plate part and a second-side plate part sandwiching and holding the seal member in an axial direction of the rotation shaft. An inner peripheral end of the second-side plate part is positioned radially outside beyond an inner peripheral end of the first-side plate part. An outer surface of the first-side plate part includes an outer peripheral-side region positioned radially outside beyond the inner peripheral end of the second-side plate part and an inner peripheral-side region positioned radially inside beyond the outer peripheral-side region. The outer peripheral-side region is positioned on a first side of the axial direction with respect to the inner peripheral-side region.