Pressure relief safety valves are designed to control steam pressure. This prevents over pressurization, which can result in serious accidents and costly damage to equipment. When the relief valve operates, there is a steam flow. During venting of the pressure, the steam is discharged to the atmosphere using an open system that could cause blow-back. The safe answer to open venting is a closed sealed venting system. The closed system eliminates steam blow-back and hazard conditions for the employees. The closed venting system uses a bellows type safety valve connector.
These 15 pressure relief safety valve connector expansion joints were manufactured from 316SS, A-335 P22, A-387 Gr22, A106, and A-516-70. They were externally pressurized to prevent steam blow back, and will be attached to the relief valves in a power plant. The expansion joints will assist in maintaining pressure as well as provide for 7″ axial and 6″ lateral travel. They can handle applicable loads of up to 150 PSIG at 535°F and 460 PSIG at 885°F, but can function if temperatures reach 1,000°F. They range from 30″ to 85″ in length and weigh between 400 lb. and 1,600 lb. Dye penetrate, air, and soap bubble tests were completed for quality and performance assurance.