A fluid end assembly comprising a plurality of fluid end sections positioned in a side-by-side relationship. Each fluid end section comprises a housing made of multiple-piece construction. One or more pieces of the housing are configured to have a plurality of stay rods attached thereto. The stay rods interconnect the fluid end assembly and a power end assembly.

A reject valve of a reverse osmosis device, which is especially suited for brackish water reverse osmosis devices, which require a low system pressure less than 15bar. The valve keeps the system pressure substantially constant in a pre-defined range of the reject volume. The size of the inflow channel is adjusted by a spring-operated cone, which never entirely closes the channel, which forms a constant throttle until the pressure of the inflow has risen to approximately three quarters of the pressure arranged by the spring and prevailing at maximum volume of the reject flow. This operation is arranged structurally such that onto the shaft of the cone is fixedly supported a transverse plate abutting the inner wall of the body, which as pressed by the compression spring is supported by the end of an element connected to the end of the body, wherein the cone is in its lowest position.

A piston valve includes a body, a valve seat, an obturator in the form of a piston and a return spring. The body includes an envelope provided with at least one outlet orifice for the pressurised fluid, and an interior element that is attached in the envelope. The interior of the body carries the valve seat and provides the translational guidance of the obturator in the body. Furthermore, the interior element includes at least one window configured to guide the fluid from the valve seat towards the outlet orifice.

A high pressure pump. The pump comprises a fluid end assembly supported on a power end assembly. The power end assembly is modular and held together by a first set of stay rods. The fluid end assembly comprises a plurality of fluid end sections positioned in a side-by-side relationship. Each fluid end section comprises a housing made of multiple-piece construction. One or more pieces of the housing are configured to having a second set of stay rods attached thereto. The second set of stay rods interconnect the fluid end assembly and a power end assembly and a vertically offset from the first set of stay rods.

A relief valve includes a polymeric ring seat, a cylindrical member, and an elastomeric seal. The cylindrical member is seated in the polymeric ring seat. The cylindrical member includes a first end, a second end, and a cylindrical wall extending from the first end to the second end. The cylindrical wall defines an inner bore having a uniform inner diameter from the first end to the second end. The cylindrical wall has a non-uniform outer diameter from the first end to the second end. An outer circumferential surface of the cylindrical wall is in contact with an inner circumferential surface of the polymeric ring seat. The elastomeric seal surrounds the polymeric ring seat. The elastomeric seal is configured to hold a relative position of the cylindrical member with respect to the polymeric ring seat.

A relief valve includes a polymeric ring seat, a cylindrical member, and an elastomeric seal. The cylindrical member is seated in the polymeric ring seat. The cylindrical member includes a first end, a second end, and a cylindrical wall extending from the first end to the second end. The cylindrical wall defines an inner bore having a uniform inner diameter from the first end to the second end. The cylindrical wall has a non-uniform outer diameter from the first end to the second end. An outer circumferential surface of the cylindrical wall is in contact with an inner circumferential surface of the polymeric ring seat. The elastomeric seal surrounds the polymeric ring seat. The elastomeric seal is configured to hold a relative position of the cylindrical member with respect to the polymeric ring seat.

A fluid routing plug for use with a fluid end section. The fluid end section being one of a plurality of fluid end sections making up a fluid end side of a high pressure pump. The fluid routing plug is installed within a horizontal bore formed in a fluid end section and is configured to route fluid throughout the fluid end section.

The present invention relates to a pressure resistance valve structure, which comprises a front valve seat body, a pressure resistance valve core body and a rear valve seat body. The pressure resistance valve core body is closed or released from the closed state relative to the front valve seat body, to control the export of liquid or gaseous fluids. The overall composition of the present invention is simple in structure, reducing the risk of component failure after long-term use, so as to achieve the effect of structural stability and good convenience of use.

A double check valve is provided that includes an in-line inlet check valve and an outlet check valve that cooperate to prevent back flow of fluid through the valve. The check valve also includes at least one vent that allows for fluid trapped within the check valve to drain, thereby preventing freezing of the check valve and hydrant to which it is interconnected. The check valve provided omits many superfluous components and thus is smaller and easier to install than check valves of the prior art.

An indicator adapted to provide a visual indication of an over pressure situation in a system. The indicator (also referred to as a pop indicator), includes a main body, a piston that is disposed in the main body, and one or more O-rings disposed around the piston. Initially, the piston is in a first position where the piston is retracted into the body. However, when an over pressure situation occurs, the pressure causes the piston to move in a direction out of the main body against a friction force created by the O-ring. When the piston is moved, i.e., popped, then end of the piston extending out of the body provides a visual indication.