Liquid Relief Valves | McMaster-Carr

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105 Products

About Pressure-Relief Valves

Precision-Adjustment
Pressure-Relief Valves for Fuel

A finely threaded adjustment screw lets you make precise set pressure adjustments.

Adjustable Pressure-Relief Valves for Fuel

To gradually relieve pressure in lines for diesel fuel, fuel oil, gasoline, and kerosene, these valves begin opening at the set pressure and fully open at about 10% over the set pressure.

Adjustable Pressure-Relief Valves for Water

Alter the set pressure to suit your application.

Pressure-Relief Valves for Water

These valves are commonly used with pumps in low-pressure water systems.

Precision-Adjustment
Pressure-Relief Valves for Water

Change set pressure without guesswork—the adjustment screw is marked in 25 psi increments for making pressure adjustments without a gauge.

Made-to-Order Pressure-Relief Valves

Design a valve specifically for your process media and set pressure. Choose from a valve for air, inert gas, water, hydraulic oil, fuel oil, gasoline, or diesel fuel and a set pressure.

Adjustable Pressure-Relief Valves for Chemicals

These valves are often used with catalysts, pH buffers, and electroplating solutions.

Pressure-Relief Valves for Cryogenic Applications

Cleaned and bagged for oxygen service and other high-purity applications, these valves are built to withstand the extreme cold of liquid carbon dioxide, liquid nitrogen, and liquid oxygen.

Pressure-Relief Valves for Oil

These valves are often used in hydraulic and lubrication systems.

Extended-Life Back-Pressure-Regulating
Valves for Water and Oil

For a longer service than cast iron valves, these have a durable bronze body and a 303 stainless steel seal.

Back-Pressure-Regulating Valves for Water and Oil

These valves have a cast iron body.

Sanitary Back-Pressure-Regulating Valves

Designed to meet 3-A sanitary standards, these valves regulate liquid, gas, and air pressure in hygienic zones of food and beverage plants.

Hydraulic Valves

Pressure-Relief Hydraulic Valves

To set the pressure, unscrew the cap and turn the adjusting screw.

Tamper-Resistant Pressure-Relief Hydraulic Valves

The pressure setting on these valves cannot be adjusted while they are installed.

Easy-Adjust Pressure-Relief Hydraulic Valves

An external nut lets you adjust the pressure without disassembling the valve.

Pressure-Relief Screw-In Hydraulic Valves

Set a specific pressure and these valves will maintain it.

Pressure-Relief Block-Mount Hydraulic Valves

Set a specific pressure and these valves will maintain it by diverting excess fluid to a tank.

Pressure-Regulating Block-Mount Hydraulic Valves

These valves maintain a consistent pressure in a system when input pressure varies.

Pressure-Regulating Inline Hydraulic Valves

When input pressure varies, use these valves to maintain a consistent pressure.