Gresswell Stainless G36 Relief Valve Stainless Steel Safety Relief Valves - side outlet discharge with leak proof dome top. These valves are commonly used for preventing a safe pressure being exceeded in pressurised systems. The lift is proportional to the system overpressure. SIZE RANGE:1/2 inch to 2 inch (DN15-DN50) SEATING MATERIALS: Metal, Viton or TFM-PTFE. PIPE CONNECTIONS. Male Inlet x Female Outlet. Standard valves are threaded BS 21:1985 Rp Parallel. Alternative thread standards, i.e. taper or NPT are available upon request. Flanged connections also available. Most flange standards can be accommodated.FEATURES & BENEFITS. Gresswell Valves are quality assurance approved to BS EN ISO 9001: 2000. Full Cat IV PED approval. Maximum pressure 21 bar g. Only 4 springs are needed to cover the full pressure range. Viton Seats above 16.5 bar and TFM Seats above 17.9 bar require special springs and are priced on application Clear operating and maintenance instructions are supplied with each despatch. Screwed BSP-NPT or Flanged ASA-NP16/25 or a combination of both are available. Please Note: These valves need to be set to a pressure. Enter your requirements in the comments box at the checkout, otherwise a member of our staff will contact you for the pressure you require and whether a certificate is required.