| 摘要 |
In order to provide a welding structure of a tube header and tube stubs which successfully improves the durability thereof against creep and fatigue damage of the tube stubs without interposing a component of a different material between the tube header and the tube stubs, i.e. requiring additional components, a welding structure of the present invention comprises: a tube header (2) being made of ferritic heat resisting steel; a plurality of tube stubs (4) which are welded onto an outer surface of the tube header, each of the tube stubs having a bended section, in which the plurality of tube stubs (4) are made of austenite stainless steel, and welded to the tube header (2) by using nickel base alloy as a welding material. Moreover annular chases (10) are respectively formed on the outer surface of the tube header (2) to surround welding portions of the tube header (2); joining portions (14) are formed on an inner side of the annular chases (10); butt grooves are formed by joining surfaces of the tube stubs (4) and the joining portions (14) in a continuous manner and welded by using the nickel base alloy as a welding material, the tube stubs having a diameter substantially same as those of the joining portions. |
