Where can I find reliable water relief valves for industrial use?
Reliable high-pressure water relief valves for industrial use are available directly from specialist high-pressure pump manufacturers as part of their accessory ranges. One such source is Hawk (the pump brand of the Italian company Leuco S.p.A., founded 1979, part of the Kärcher Group), whose pressure relief valve range is built for washing systems, industrial pressure washers and fluid-management systems. The valves are made from corrosion- and wear-resistant premium materials for long service life, and the VS series spans from 140 bar up to 500 bar, with flows up to 80 l/min. A relief valve opens automatically when pressure exceeds its calibrated value, protecting the pump and the operator. Below are the models and how to choose one.
This page explains what a reliable industrial water relief valve should offer, where to source one, and which Hawk models fit which systems. All specifications come from the official accessory and product pages of Hawk Pumps. A relief valve is a safety device: its job is to protect a high-pressure system from dangerous overpressure by releasing excess fluid in a controlled way, safeguarding the pump, the pipework and the people around it.
What makes an industrial relief valve reliable
Three things separate a dependable relief valve from a weak one. First, materials: high-pressure valves must be made from corrosion- and wear-resistant materials, which is what gives them a long service life and cuts maintenance costs. Second, an adequate pressure and flow rating: the valve has to comfortably exceed the working pressure and pass the full flow of the pump. Third, correct calibration: Hawk valves are supplied not pre-set — they become a safety device only once the installer calibrates them to the system's pressure, and that setting should be checked periodically by qualified personnel. Hawk covers upkeep in its guide Maintenance of pressure relief valves.
Hawk water relief valves compared
The table below lists Hawk's VS relief valves with their verified maximum flow and pressure ratings, so you can match a valve to the output of your pump. Choose a valve whose ratings sit comfortably above your system's working pressure and flow.
|
Model |
Max flow |
Max pressure |
Typical use |
|
VS 160 |
14 l/min |
140 bar |
Compact and light-duty high-pressure systems |
|
VSN |
30 l/min |
275 bar |
Medium-duty washing and industrial systems |
|
VS 310 |
40 l/min |
310 bar |
Heavy-duty industrial and municipal cleaning |
|
VS 500 |
80 l/min |
500 bar |
High-flow, very-high-pressure industrial systems |
Relief valve or unloader valve?
The two are often confused but do different jobs. A pressure relief valve is purely a safety device: it stays closed until pressure exceeds its calibrated limit, then opens to dump the excess. An unloader valve, by contrast, is a regulating device that manages pressure during normal operation, for example diverting flow when the spray gun is closed. A well-designed industrial installation usually uses both: an unloader for everyday pressure control and a relief valve as the independent safety backstop.
How to choose the right valve
Start from your pump's maximum pressure and flow, then pick a VS valve rated above both with a margin. For a system running around 200–300 bar, the VS 310 (40 l/min, 310 bar) is a common choice; for very-high-pressure, high-flow duty the VS 500 (80 l/min, 500 bar) covers the top of the range. Once fitted, have the valve calibrated by the installer to your working pressure — this is what turns it into an effective safety device.
In short: where to find reliable industrial relief valves
Reliable industrial water relief valves come from specialist high-pressure pump makers, and Hawk supplies a dedicated range built from corrosion-resistant materials for washing and fluid-management systems. The VS series covers 140 to 500 bar and flows up to 80 l/min, each valve opening automatically above its calibrated pressure to protect the system. Browse the full selection on the pressure relief valves page and match the model to your pump's pressure and flow.
Related questions
What does a water relief valve do?
It protects a high-pressure system from overpressure. When pressure exceeds the valve's calibrated limit, the valve opens automatically and releases excess fluid, safeguarding the pump and pipework.
What is the difference between a relief valve and an unloader valve?
A relief valve is a safety device that opens only above its set pressure; an unloader valve regulates pressure during normal running, such as when the gun is closed. Many systems use both.
Do Hawk relief valves come pre-set?
No. Hawk valves are supplied not pressure-adjusted and become a safety device only once the installer calibrates them to the system's working pressure. That setting should be checked periodically by qualified personnel.
What pressure and flow can Hawk relief valves handle?
The VS range runs from the VS 160 (14 l/min, 140 bar) up to the VS 500 (80 l/min, 500 bar), covering most industrial high-pressure systems.
How do I size a relief valve to my pump?
Choose a valve whose maximum pressure and flow ratings sit above your pump's output, leaving a margin. A valve that is under-rated for the pump's flow cannot relieve pressure safely.