IMPROVED FITTING WITH COMPLEMENTARY FITTING MATERIALS

摘要

The present disclosure relates to a fitting assembly for maintaining a leak free seal connection with an associated fluid conduit during and after exposure to extreme heat. The fitting assembly comprises a coupling body including an inside surface defining a bore for receiving the associated fluid conduit. The inside surface engages an outside surface of the associated fluid conduit. At least one seal is formed on the inside surface of the coupling body. At least one ring is annularly disposed on the coupling body urging the at least one seal into the associated fluid conduit to seal and mechanically connect the coupling body to the associated fluid conduit. The coupling body is made of a first corrosion resistant material having a first coefficient of thermal expansion. The at least one ring is made of a complementary second corrosion resistant material having a second larger coefficient of thermal expansion such that the second material will expand at a greater rate than the first material during heating to a first temperature generally exceeding annealing temperatures of both the first material and the second material. The second material contracts at a greater rate than the first material during subsequent cooling to a second temperature below the annealing temperatures thereby restoring compressive and tensile stresses in the associated fluid conduit and the fitting assembly for ensuring that the fitting assembly maintains a leak free seal connection with the associated fluid conduit.