Relief Valves

BiS Wells offer a range of Pressure Relief Valves. These safety relief valves are CE marked and conform to category IV of the Pressure Equipment Directive (PED). Unlike our back pressure maintaining valves (BPMV’s) these valves are not designed to maintain system pressure, instead they are designed to only operate only in an emergency, where there is risk of the system becoming over pressurised and potentially dangerous.

These pressure relief valves are sprung loaded for reliability and are adjustable via a hex head screw. Depending on pressure and flow will determine which type of pressure relief valve is most suited to your application.

Our relief valves can handle pressures from 10 Psi up to 6,500 Psi. Valves are offered in Stainless Steel as standard but can be manufactured from other materials if required. Valves can be supplied with 1/4”, 3/8”, 1/2” or 3/4” ports.

Our pressure relief valves are suitable for both pneumatic and hydraulic applications, please see our overview datasheets for suitability. As standard valves are offered with Nitrile or Viton seals however please contact us for medium compatibility as other elastomeric materials can be offered.

All our pressure relief valves can be manufactured specially for Oxygen use, please contact us for more information.

Product Datasheets

Relief Valves Overview Datasheet

Data Sheets and Installation Drawings

C10 Relief Valve. 1/2″ Male Inlet and 3/8″ Female Outlet. 241 Bar (3,500 Psi)

C11 Relief Valve. 1/2″ Male Inlet and 3/8″ Female Outlet. 450 Bar (6,500 Psi)

C45 Relief Valve. 1/4″ Male Inlet and 1/4″ Female Outlet. 40 Bar (580 Psi)

Coming Soon – Full range of installation drawings

Installation Operation and Maintenance Manuals

General Instructions IOM – Relief Valves


+44 1202 851462

BiS Wells Ltd
Units 17-23 Kingfisher Park, Collingwood Road,
West Moors, Wimborne, Dorset, BH21 6US

Opening hours:
Monday to Thursday: 08:00 – 16:30
Friday: 08:00 – 13:00
Saturday and Sunday: Closed