DA21F-40P Cryogenic Spring Micro-Opening Safety Valve, 304 Stainless Steel External Thread PTFE Seal, LNG LO2 LN2 LAr Cryogenic Tank Relief Valve

**DA21F-40P cryogenic safety valve** is spring micro-opening right-angle cryogenic safety valve, no wrench design, external thread connection, CF8 (304) stainless steel body. F stands for PTFE soft seal, nominal pressure PN40. Cryogenic soaking treatment before delivery to eliminate cold shrinkage deformation, sensitive popping and reliable resealing under ultra-low temperature. Sizes DN10, DN15, DN20, DN25. Suitable for LNG, LO2 liquid oxygen, LN2 liquid nitrogen, LAr liquid argon, liquid CO₂, temperature range -196℃～+80℃. When pressure inside cryogenic tank, cryogenic tanker, vaporizer or pipeline exceeds set pressure, DA21F-40P opens automatically for pressure relief and reseats after pressure drop to protect cryogenic pressure equipment. **DA21F-40P with TS special equipment manufacturing license, factory certificate available and third-party inspection supported**. Widely used for air separation unit, cryogenic storage tank, LNG pipeline, cryogenic liquid tanker and cryogenic vaporizer. Complies with GB/T12243, GB, JIS, ASME available, custom set pressure. Degreasing treatment required before service for oxygen application.