Seal for removable cover - having circular section metal sealing ring and spring tensioner

摘要

Seal is for removable cover on pressure vessels, the cover having a projecting lip with a circular rim on the end. A seal chamber is formed between the inner wall of the vessel and the lip into which a sealing ring fits. This is held in position by screws above, and the upwards thrust of the vessel pressure on the cover causes this to contact the seal. The ring is made of metal and has a circular cross section. A prestressed spring element is inserted between the tensioning screws and the seal ring. This can be a plate spring. From the projection on the cover which forms one sealing surface to the inner surface of the vessel is an acute angle and the circular seal is pressed into this wedge shaped slot. It has a flat upper surface which contacts the compression ring above. Used on medium pressure vessels esp. nuclear power plant, operating at pressure and temp. where conventional compressible seals are subject to attack from materials in the vessel. This seal overcomes thse problems and gives prolonged usage, esp. for relief valve cover seals.