A valve member for a spring-loaded valve assembly includes a top portion having a spring retaining recess, the spring retaining recess extending into the top portion to form a void space, the void space to receive at least one coil of a spring, the spring retaining recess having a recess diameter that is smaller than a top portion diameter, wherein the recess diameter is larger than a rest diameter of a spring base including the coil, the spring retaining recess blocking expansion of the at least one coil when the spring is compressed. The valve member also includes a bottom portion coupled to the top portion. The valve member further includes a sealing element positioned axially below a shoulder of the top portion and legs coupled to the bottom portion.

A pressure relief valve includes a valve body including a monitored pressure inlet leading to a monitored pressure region, a piston having a shear seal bore and a surface facing the monitored pressure region, a vent passage and a the shear seal assembly comprising a seal plate having a sealing surface thereon, and the shear seal assembly includes a sealing surface facing the seal plate and having a first annular area, and a first surface having an annular surface area at least twice as large as the first area of the sealing surface, the first surface facing away from the first area, and a biasing seal in contact with the first surface.

A valve includes a valve axis extending in an axial direction, a valve housing, a ring that surrounds the valve axis, a seal, a spring for exerting a spring force, and a piston arranged in the valve housing. The valve housing includes a first valve housing opening through which a flow medium can pass. The ring is secured to the first valve housing opening. The seal is held on the valve housing by the ring. The piston is coaxial to the valve housing on the valve axis and axially faces the first valve housing opening. The piston is axially movable in the valve housing against the spring force, and the first valve housing opening can be closed by the piston.

A valve includes a valve axis extending in an axial direction, a valve housing, a ring that surrounds the valve axis, a seal, a spring for exerting a spring force, and a piston arranged in the valve housing. The valve housing includes a first valve housing opening through which a flow medium can pass. The ring is secured to the first valve housing opening. The seal is held on the valve housing by the ring. The piston is coaxial to the valve housing on the valve axis and axially faces the first valve housing opening. The piston is axially movable in the valve housing against the spring force, and the first valve housing opening can be closed by the piston.

A piston check valve system includes a body including an upstream end and a downstream end, a bonnet secured to a proximal opening of the body, and a piston secured within the body, the piston being moveable between a closed position in which the piston rests upon a valve seat and an open position in which the piston is spaced away from the valve seat. The piston check valve system also includes a retainer configured to guide and retain the piston and to secure the valve seat within the body.

A pressure relief valve includes a valve body including a monitored pressure inlet leading to a monitored pressure region, a piston having a shear seal bore and a surface facing the monitored pressure region, a vent passage and a the shear seal assembly comprising a seal plate having a sealing surface thereon, and the shear seal assembly includes a sealing surface facing the seal plate and having a first annular area, and a first surface having an annular surface area at least twice as large as the first area of the sealing surface, the first surface facing away from the first area, and a biasing seal in contact with the first surface.

A valve member for a spring-loaded valve assembly includes a top portion having a spring retaining recess, the spring retaining recess extending into the top portion to form a void space, the void space to receive at least one coil of a spring, the spring retaining recess having a recess diameter that is smaller than a top portion diameter, wherein the recess diameter is larger than a rest diameter of a spring base including the coil, the spring retaining recess blocking expansion of the at least one coil when the spring is compressed. The valve member also includes a bottom portion coupled to the top portion. The valve member further includes a sealing element positioned axially below a shoulder of the top portion and legs coupled to the bottom portion.

A hydraulic control apparatus includes an output-side oil passage into which oil from a first oil passage and oil from a second oil passage flow, and a pressure regulating check valve regulating a hydraulic pressure in the second oil passage. The pressure regulating check valve includes first and second elastic portions housed in a spool hole between a valve body and a bottom of the spool hole. A natural length of the second elastic portion is shorter than a distance between the valve body and the bottom when the valve body closes an inflow hole. The second elastic portion applies an elastic force to the valve body in a state in which the valve body opens the inflow hole.

A relief valve that includes a tube; a valve configured to slide along an inner wall of the tube in an axial direction, and a spring that urges the valve, wherein the valve has a hydraulic pressure receiving surface on a first axial side that is one side in the axial direction, and a spring abutment against which the spring abuts, on a second axial side opposite to the first axial side, and the tube has a discharge oil passage having an opening in the inner wall and extending through the inner wall in a radial direction.

A piston check valve system includes a body including an upstream end and a downstream end, a bonnet secured to a proximal opening of the body, and a piston secured within the body, the piston being moveable between a closed position in which the piston rests upon a valve seat and an open position in which the piston is spaced away from the valve seat. The piston check valve system also includes a retainer configured to guide and retain the piston and to secure the valve seat within the body.