METHOD AND STRUCTURE FOR CONNECTING DIFFICULT−TO−JOIN PIPES TO BE USED AT HIGH TEMPERATURE

摘要

Pipes (2, 3) made of a difficult−to−weld material to be used at a high temperature are internally (3a) or externally (2a) threaded at their end portions, and are thread−fastened to each other. The inner and/or outer faces of the jointed pipe portion (1) is sealed by seal means (7, 9), so that the pipes (2, 3) made of the difficult−to−weld material to be used at a high temperature are jointed by the screw structure thereby to retain the mechanical strength of the jointed pipe portion (1). At the same time, the inner and/or outer faces of the jointed pipe portion (1) is sealed by the seal means (7, 9) to retain the gas tightness of the jointed pipe portion (1).