The knife gate valve is designed with at least one sealing belt mounted in the valve body and which act between the valve's seat and the gate to protect them from abrasive wear, the knife gate valve may have at least one cleaning plate to displace abrasive particles from the sealing belt and prevent abrasive particles from getting stuck between it and the seat.

A valve removal method of a fluid pipeline structure, which removes an unnecessary portion of a valve device from a connection port portion side of a pipe without flow disruption in the fluid pipeline structure that detachably includes the valve device including a valve body, which is openable and closeable from a direction intersecting a flow path axis of a connection port portion, on the connection port portion side of the pipe connected to a fluid piping system includes a valve body fixing step of fixing the valve body at a closed valve position to the connection port portion side in a sealed manner; and a valve component removing step of removing other unnecessary valve components of the valve device in a state where the valve body which is fixed in a sealed manner is left on the connection port portion side.

A valve removal method of a fluid pipeline structure, which removes an unnecessary portion of a valve device from a connection port portion side of a pipe without flow disruption in the fluid pipeline structure that detachably includes the valve device including a valve body, which is openable and closeable from a direction intersecting a flow path axis of a connection port portion, on the connection port portion side of the pipe connected to a fluid piping system includes a valve body fixing step of fixing the valve body at a closed valve position to the connection port portion side in a sealed manner; and a valve component removing step of removing other unnecessary valve components of the valve device in a state where the valve body which is fixed in a sealed manner is left on the connection port portion side.

A frac pump valve seat assembly includes a seat body and a wiper seal. The seat assembly is configured to mitigate the risk of fluid end erosion in the valve seating area by automatically clearing or wiping the mating surface of the fluid end at the time of installation. The wiper seal is located at a lower portion of the seat body and is designed to interface therewith the mating surface of the fluid end. Upon installation, the wiper seal scrapes or cleans the mating surface of propellants, sand, and other contaminants that may remain after initial cleaning. The contact surface of the seat body is optionally further reinforced with material implants with greater hardness than the material of the seat body.

A pressure control valve includes a spool that strokes to one side in the direction of an axis due to the conduction of current to a coil, a spring that urges the spool to the other side in the axis direction, a control device for controlling the conduction of the current to the coil, a determination unit for determining the start of a foreign substance removing operation by the spool, a command value setting unit for setting a command value for the current conducted to the coil, and a dither current setting unit for setting a dither current superimposed on the command value. When the determination unit determines the start of the foreign substance removing operation, the dither current setting unit changes an oscillation frequency of the dither current to an oscillation frequency lower than the frequency at the current point in time, and the command value setting unit periodically increases and reduces the command value on which the changed oscillation frequency is superimposed.

A wiper (200a) for a blowout preventer having an adapter ring (102a) and a piston (104a) slideable relative to the adapter ring along an interface can include a base (202) adapted to couple the wiper to the adapter ring and a head (204) coupled to the base. The head can include a first portion adapted to bridge the interface and contact the piston and a second portion adapted to contact the adapter ring and support the first portion. The second portion of the head can be adapted to at least partially resist rotation of the wiper. A blowout preventer can include one or more wipers as shown and described.

A pressure control valve includes a spool that strokes to one side in the direction of an axis due to the conduction of current to a coil, a spring that urges the spool to the other side in the axis direction, a control device for controlling the conduction of the current to the coil, a determination unit for determining the start of a foreign substance removing operation by the spool, a command value setting unit for setting a command value for the current conducted to the coil, and a dither current setting unit for setting a dither current superimposed on the command value. When the determination unit determines the start of the foreign substance removing operation, the dither current setting unit changes an oscillation frequency of the dither current to an oscillation frequency lower than the frequency at the current point in time, and the command value setting unit periodically increases and reduces the command value on which the changed oscillation frequency is superimposed.

A frac pump valve seat assembly includes a seat body and a wiper seal. The seat assembly is configured to mitigate the risk of fluid end erosion in the valve seating area by automatically clearing or wiping the mating surface of the fluid end at the time of installation. The wiper seal is located at a lower portion of the seat body and is designed to interface therewith the mating surface of the fluid end. Upon installation, the wiper seal scrapes or cleans the mating surface of propellants, sand, and other contaminants that may remain after initial cleaning. The contact surface of the seat body is optionally further reinforced with material implants with greater hardness than the material of the seat body.

A wiper (200a) for a blowout preventer having an adapter ring (102a) and a piston (104a) slideable relative to the adapter ring along an interface can include a base (202) adapted to couple the wiper to the adapter ring and a head (204) coupled to the base. The head can include a first portion adapted to bridge the interface and contact the piston and a second portion adapted to contact the adapter ring and support the first portion. The second portion of the head can be adapted to at least partially resist rotation of the wiper. A blowout preventer can include one or more wipers as shown and described.

Cleaning reamer devices and methods for cleaning the interior of a valve guide are described. One cleaning reamer includes a straight shank, a body, and a piloted portion. The piloted portion is dimensionally sized and shaped to be substantially equivalent to the valve stem that is positioned within the valve guide to be cleared of deposits. The body of the cleaning reamer is fluted or straight.