Embodiments of the present disclosure include a valve sleeve for forming at least a portion of a valve flow passage. The valve sleeve includes a seat end having a seat face, the seat end extending at least partially into a chamber of a valve body. The valve sleeve also includes a sleeve portion coupled to the seat end and having a coupling end opposite the seat face, the coupling end comprising a retaining mechanism for removably coupling the valve sleeve to the valve body. The valve sleeve further includes an opening extending along a length of the valve sleeve, the opening forming at least a portion of the valve flow passage and having a generally circular cross section.

Embodiments of the present disclosure include a valve sleeve for forming at least a portion of a valve flow passage. The valve sleeve includes a seat end having a seat face, the seat end extending at least partially into a chamber of a valve body. The valve sleeve also includes a sleeve portion coupled to the seat end and having a coupling end opposite the seat face, the coupling end comprising a retaining mechanism for removably coupling the valve sleeve to the valve body. The valve sleeve further includes an opening extending along a length of the valve sleeve, the opening forming at least a portion of the valve flow passage and having a generally circular cross section.

A valve control assembly includes a valve body having an inlet adapted to be coupled to a source of process fluid having a first temperature, an outlet, and a fluid flow path extending between the inlet and the outlet, and a bonnet coupled to the valve body. An inlet port, an outlet port, an annular plenum, an inlet passage, and an outlet passage are integrally formed in the valve body or the bonnet. The inlet port is adapted to be coupled to source of media and the annular plenum is disposed between the inlet port and the outlet port, immediately adjacent a portion of the fluid flow path. The inlet passage directs the media from the inlet port to the annular plenum, which changes a temperature of the process fluid flowing through the fluid flow path from the first temperature to a second temperature different from the first temperature.

A pair of air cylinders that cause a valve plate to perform an opening/closing operation each include a head-side air cushion mechanism and a rod-side air cushion mechanism. Each head-side air cushion mechanism includes a head-side communication path and a head-side restricting flow path that connect a head-side pressure chamber and a head-side main flow path in parallel, and a blocking mechanism that blocks the head-side communication path when a piston approaches a retreat stroke end, and each rod-side air cushion mechanism includes a rod-side communication path and a rod-side restricting flow path that connect a rod-side pressure chamber and a rod-side main flow path in parallel, and a blocking mechanism that blocks the rod-side communication path when the piston approaches an advance stroke end.

A valve in an embodiment includes: a valve box in which valve box seat portions are provided; and a valve element on which valve element seat portions are provided. One of the valve box seat portion and the valve element seat portion is formed of a build-up material of a Co-based alloy and the other of the valve box seat portion and the valve element seat portion is formed of a build-up material of an Fe-based alloy. Then, a Vickers hardness of the build-up material of the Co-based alloy is larger than a Vickers hardness of the build-up material of the Fe-based alloy and a difference in the Vickers hardness between the build-up material of the Co-based alloy and the build-up material of the Fe-based alloy is HV50 or more.

A valve having improved resistance to black powder wear and damage includes a valve body defining a flow passage therethrough, an upper bonnet assembly defining a stem opening, and a stem passing through the stem opening. The valve also includes an elongate gate having a proximal end operatively attached to the stem, a distal end, an orifice sized and adapted to permit essentially unopposed passage of material through the gate when the orifice is aligned with the flow passage of the valve body, the orifice being located proximate the proximate end of the gate, and a solid portion sized and adapted to substantially completely block the flow of material through the gate when the solid portion is aligned with the flow passage of the valve body, the solid portion being located distally of the orifice such that the orifice is located between the proximal end and the solid portion.

A valve having improved resistance to black powder wear and damage includes a valve body defining a flow passage therethrough, an upper bonnet assembly defining a stem opening, and a stem passing through the stem opening. The valve also includes an elongate gate having a proximal end operatively attached to the stem, a distal end, an orifice sized and adapted to permit essentially unopposed passage of material through the gate when the orifice is aligned with the flow passage of the valve body, the orifice being located proximate the proximate end of the gate, and a solid portion sized and adapted to substantially completely block the flow of material through the gate when the solid portion is aligned with the flow passage of the valve body, the solid portion being located distally of the orifice such that the orifice is located between the proximal end and the solid portion.

A gate valve includes a first plate with a first opening; a second plate with a second opening positioned opposite the first plate such that the first opening is aligned with the second opening; a gate with a gate opening positioned between the first plate and second plate and movable from a close position where the gate blocks flow through the first opening and the second opening and an open position where the gate opening aligns with the first opening and the second opening to allow flow through the valve; and a wear ring lining the gate opening.

A gate valve includes a first plate with a first opening; a second plate with a second opening positioned opposite the first plate such that the first opening is aligned with the second opening; a gate with a gate opening positioned between the first plate and second plate and movable from a close position where the gate blocks flow through the first opening and the second opening and an open position where the gate opening aligns with the first opening and the second opening to allow flow through the valve; and a wear ring lining the gate opening.

A shear blade 10 for a downhole apparatus 50 comprises a body portion 12 and a first cutting edge 21 provided at a cutting end of the shear blade 10, the first cutting edge 21 comprising a sharp edge 22 located at or near a central region of the first cutting edge 21 and at least one blunt edge 23 located at or near at least one outer portion of the first cutting edge 21. In an embodiment, the shear blade 10 has a recess or slot 40 which is provided at or near a central region of a shear face 30 and which extends partially between a first side 27 and a second side 28 and which is generally aligned with the sharp edge 22 of the first cutting edge 21 in a plane substantially parallel to an axis of the throughbore and perpendicular to the first cutting edge 21.