A pressure relief valve includes a housing, a poppet, and a spring. The housing includes an internal bore defined along a longitudinal axis of the housing and extending from an upper portion to a lower portion. A ledge or seat is defined within the bore. At least one lower portion hole is defined from an outer surface of the lower portion and into the bore. At least one upper portion hole is defined from an outer surface of the upper portion and into the bore. The poppet is slidably engaged within the internal bore. The poppet includes a head, a shaft, and an internal channel that runs longitudinally through the entire poppet. The head includes a shoulder. The spring is disposed within the bore at the upper portion of the housing and biases the poppet downwards so that the shoulder abuts the ledge or seat.

A valve of a piston pump for a vehicle brake system having a closing body which is resiliently preloaded against a sealing seat. The closing body is formed in two parts with a damping piston and a closing element inserted therein. The damping piston is axially displaceably guided in a cylindrical piston guide. At least one flow channel is provided between the damping piston and the piston guide. The at least one flow channel is configured such that fluid can flow around the damping piston in the longitudinal direction thereof through the at least one flow channel.

A flow regulating valve and a compressor with the flow regulating valve are disclosed. The flow regulating valve includes: a valve seat in which a passage is formed to allow fluid to enter; a guide member protruded outwards from the valve seat; a piston which is disposed on the outside of the valve seat, forms a fluid inlet with the valve seat, and is capable of being reciprocated along the guide member; and a biasing member biasing the piston in a direction away from the valve seat. A force exerted by the incoming fluid on the piston is opposite in direction to a biasing force exerted by the biasing member on the piston. The piston is able to be moved to different positions under the action of different forces to form fluid inlets of different widths with the valve seat, thereby controlling the mass flow rate of the incoming fluid (especially liquid). With the technical solutions of the present invention, the flow rate of the fluid entering the compressor can be effectively adjusted with a simple structure and low cost.

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 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 relief valve, capable of reducing pressure of fuel in a discharge passage and including a valve housing having a communication hole and a valve member provided in a reciprocating manner against the valve housing, where the valve member regulates a flow of the fuel between a discharge passage and a fuel chamber when the valve member is brought into contact with an inner wall formed around the communication hole. T the valve member also allows the flow of the fuel between the discharge passage and the fuel chamber when the valve member is separated from the inner wall. The relief valve further including a spring that biases the valve member such that the valve member and the inner wall are in contact with each other an adjusting pipe and a stopper.

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 valve including a body including at least one admission opening and at least one discharge opening, a slide valve sliding in the body, the slide valve defining a chamber, with the body, and including a head arranged facing a seat of the admission opening, a spring pressing the head of the slide valve against the seat, a lip for applying the head to the seat. The head includes at least one hole bringing the chamber into communication with the discharge opening, each hole being arranged facing the seat and downstream from the lip in relation to the admission opening in order to reduce the pressure in the chamber by a Venturi effect when the slide valve is open.

A valve assembly for a fracturing pump includes a valve seat having a bore extending therethrough, the valve seat including a strike face at a top region opposite a bottom region, at least a portion of the strike face formed by an insert positioned within a groove formed in the valve body. The valve assembly also includes a bore liner arranged within the bore, at least a portion of an axial length of the bore liner covering at least a portion of the ceramic to form a barrier between the insert and the bore. The valve assembly further includes a valve member positioned to reciprocate within the bore, the valve member moving between an open position and a closed position, wherein at least a portion of the valve member engages at least a portion of the strike face in the closed position.

A pressure reducing valve includes a piston disposed in a cylinder chamber; a valve element that is coupled to the piston and opens and closes a valve seat; a valve spring that biases the valve element in a direction in which the valve element is moved away from the valve seat; and a biasing member that biases the valve seat toward a side opposite to the piston. The pressure reducing valve is configured to reduce a primary pressure of a fluid to a secondary pressure. The valve seat is disposed such that the valve seat reciprocates in the same direction as a direction in which the valve element reciprocates in the primary pressure chamber. As a difference between the primary pressure and the secondary pressure increases, the valve seat moves toward the secondary pressure chamber.