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 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 relief valve includes: a housing having a hollow cylindrical valve chamber and having a first communication port opening on one end side of the valve chamber; a first valve element for opening and closing the first communication port; a first spring for biasing the first valve element in the closing direction; and a retainer having a spring seat for supporting the first spring. A set load of the first spring is adjusted based on the press-fit amount of the retainer with respect to the housing. A press-fit piece member including a plurality of press-fit pieces is formed in the retainer, such that the press-fit pieces of the press-fit member are arranged to be spaced away from each other in the circumferential direction of the retainer and elastically abut the housing.

A relief valve includes: a housing having a hollow cylindrical valve chamber and having a first communication port opening on one end side of the valve chamber; a first valve element for opening and closing the first communication port; a first spring for biasing the first valve element in the closing direction; and a retainer having a spring seat for supporting the first spring. A set load of the first spring is adjusted based on the press-fit amount of the retainer with respect to the housing. A press-fit piece member including a plurality of press-fit pieces is formed in the retainer, such that the press-fit pieces of the press-fit member are arranged to be spaced away from each other in the circumferential direction of the retainer and elastically abut the housing.

Systems, devices, and methods of modulating a pressure relief valve are provided. A modulating pilot valve assembly can receive an inlet pressure of an inlet of a pressure relief valve and can receive a dome area pressure of a dome area of the pressure relief valve. The modulating pilot valve assembly and the pressure relief valve can be configured to maintain a leak-tight seal until reaching a pilot valve pressure set point, at which the modulating pilot valve assembly instantly reduces the dome area pressure instantly, via a biasing mechanism of the modulating pilot valve assembly causing the pressure relief valve to initially open and thereafter to progressively reduce the dome area pressure in proportion to an increase in the inlet pressure and to cause the pressure relief valve to open in proportion to the increase in the inlet pressure.

A relief valve device having a spring, a valve bonnet, a valve stem, a disc holder, a valve disc, a huddling chamber, a blowdown ring, and a nozzle. In the valve device, the valve disc is positioned above the nozzle; the spring is disposed in the valve bonnet; the spring surrounds the valve stem such that a longitudinal axis of the spring and a longitudinal axis of the valve stem are coaxial; the disc holder surrounds an outer periphery of the valve disc and is adjacent and in direct contact with a surface of the valve disc around an entire perimeter of the valve disc; the blowdown ring is disposed at a top section of the nozzle; a bottom section of the nozzle is connected to a bottom surface of a valve body and the top section of the nozzle is connected to the valve disc; and the disc holder is filled with oil.

A relief valve device having a spring, a valve bonnet, a valve stem, a disc holder, a valve disc, a huddling chamber, a blowdown ring, and a nozzle. In the valve device, the valve disc is positioned above the nozzle; the spring is disposed in the valve bonnet; the spring surrounds the valve stem such that a longitudinal axis of the spring and a longitudinal axis of the valve stem are coaxial; the disc holder surrounds an outer periphery of the valve disc and is adjacent and in direct contact with a surface of the valve disc around an entire perimeter of the valve disc; the blowdown ring is disposed at a top section of the nozzle; a bottom section of the nozzle is connected to a bottom surface of a valve body and the top section of the nozzle is connected to the valve disc; and the disc holder is filled with oil.

A fluid pressure reducing valve apparatus includes a pressure reducing valve. The valve has: a body containing a fluid-flow chamber, a liquid supply orifice into the chamber, a liquid outlet from the chamber, a regulation plate opposed to the orifice, a spring acting to urge the plate towards the orifice, and a diaphragm between the plate and the body to close the chamber between them. A controllable motor drive acts between the body and an end of the spring remote from the plate. A flow meter is positioned downstream of the outlet. A controller is arranged to receive flow data from the flow meter and to control the motor drive for withdrawal of the remote end of the spring in accordance with flow rate measured by the flow meter. For an increase in demand flow, the plate is partially withdrawn to maintain downstream pressure on such increase and vice versa.

A fluid pressure reducing valve apparatus includes a pressure reducing valve. The valve has: a body containing a fluid-flow chamber, a liquid supply orifice into the chamber, a liquid outlet from the chamber, a regulation plate opposed to the orifice, a spring acting to urge the plate towards the orifice, and a diaphragm between the plate and the body to close the chamber between them. A controllable motor drive acts between the body and an end of the spring remote from the plate. A flow meter is positioned downstream of the outlet. A controller is arranged to receive flow data from the flow meter and to control the motor drive for withdrawal of the remote end of the spring in accordance with flow rate measured by the flow meter. For an increase in demand flow, the plate is partially withdrawn to maintain downstream pressure on such increase and vice versa.

Systems and methods described herein provide for pressure relief valve detection and monitoring. A valve assembly includes a striker and an indicator assembly separated by a diaphragm. The diaphragm may be elastically or permanently deformable. The striker may be connected to a relieve valve disk that releases in response to high fluid pressure at the valve. Movement of the striker may be detected by contact with the diaphragm or by sensors near the diaphragm, which may trigger the indicator assembly to provide an external indication of a valve opening.