Back Pressure Valves/Relief Valves for Motor-Driven Metering Pumps

Back Pressure Valve/Relief Valve Type DHV-U

Universal back pressure valves of the DHV-U product range are back pressure-free piston diaphragm valves with an internal flow. They are used to generate a constant back pressure and also as relief valves. They can be installed at any location in the pipework system.

Back pressure valves are used to generate a constant back pressure for precise pumping and to protect against over-metering where there is a free outlet, fluctuating back pressure or priming pressure on the suction side. They are also used in conjunction with pulsation dampers to generate low-pulsation metering.

Relief valves are used to protect pumps, pipes and fittings from overpressure, in the event of incorrect operation or blockages in the bypass. In the event of a malfunction, the pump pumps around the circuit or back into the supply tank.

Important: Back pressure valves cannot be used as absolutely leak-tight shut-off devices. Take appropriate safety precautions when handling hazardous media. Relief valves are not safety valves by their definition as per DIN EN ISO 4126-1.

Important: Take appropriate safety measures (e.g. flushing after possible response) when using as relief valves in conjunction with viscous media (e.g. lime milk).

Adjustable pressure    0.5 - 10 bar

Application of PPE/PPB/PCE/PCB

20 °C - max. operating pressure 10 bar

Application of PVT/PVE/SST

30 °C - max. operating pressure 10 bar

Materials used

Dimensions of DHV-U (PP, PVC, PVDF design)

Dimensions of DHV-U (SS version)

Back Pressure Valve/Relief Valve Type DHV-U in physiologically safe design (FDA)

Back pressure valves for motor-driven metering pumps are designed for different applications. Please refer to the relevant notes for the different designs.

Relief valves are used in the bypass to protect pumps, pipes and fittings from overpressure in the event of incorrect operation or blockages. In the event of a malfunction, the pump pumps back into the storage tank.

Adjustable pressure    0.5 - 10 bar

Application of PPE/PPB/PCE/PCB

20 °C - max. operating pressure 10 bar

Application of PVT/PVE/SST

30 °C - max. operating pressure 10 bar

Materials used

All wetted materials in the 'Physiologically safe (FDA) in respect of wetted materials' design comply with the following FDA guidelines:

We are happy to supply back pressure valves and relief valves DHV-U/DHV-UR in stainless steel and wetted EC 1935/2004 on request.

Relief valve type DHV-UR

The universal relief valves type DHV-UR, like all valves of the DHV-U product range, are infinitely adjustable piston diaphragm valves with internal flow. In the event of impermissible overpressure, the internal piston diaphragm opens the second outlet line, the relief outlet. It can be installed at any location in the pipework system. Very low pressure losses with a closed relief valve due to virtually free pipe cross-section Simple spare parts management, the wear parts (pressure spring, diaphragms, plunger seal, seal connection set) correspond to the DHV-U range of valves.

The benefits of the new relief valves DHV-UR include simpler assembly due to the saving of installation material/connection parts etc. and a reduction of adhesion points. The new installation method permits a slimmer design of metering stations.

Relief valves for fitting directly into the discharge line of the motor-driven metering pump with the functions:

• Installation at any location in the pipework system.
• Very low pressure losses with a closed relief valve due to virtually free pipe cross-section

Adjustable pressure

0.5 – 10 bar

Application of PP and PVC (PPE/PPB/PCE/PCB)

20 °C - maximum operating pressure 10 bar

Application of PVDF and stainless steel (PVT/SST)

30 °C - maximum operating pressure 10 bar

The benefits for you:

• Simpler installation due to saving of installation material/connecting parts
• Reduced adhesion points.
• Slimmer construction type of metering stations.
• Simple spare parts management, wear parts conform to the DHV-U valve product range.

Materials used

Dimensions of DHV-UR (PP, PVC, PVDF design)

Dimensions of DHV-UR (SS design)