Combined connecting pipe fitting

The utility model provides a combined connecting pipe fitting which comprises a thin-wall metal pipe body and at least one metal lining, and the thin-wall metal pipe body is hollow and is provided with at least one open connecting end. The at least one metal lining is completely or partially connected to the at least one open connecting end of the metal pipe body in a sleeving mode and connected to the metal pipe body in a welded mode. The metal lining is hollow, and threads connected with an external pipeline are arranged on the peripheral wall of the metal lining. The wall thickness of the metal lining is larger than the maximum wall thickness of the metal pipe body, the overlapped part of the metal lining and the metal pipe body forms a sleeving area, and the length of the sleeving area is larger than or equal to 0.2 time of the outer diameter of the metal lining. 本发明提供一种组合式连接管件，其包括薄壁的金属管体和至少一个金属衬套，薄壁的金属管，呈中空状且具有至少一个敞口连接端。至少一个金属衬套全部或部分套接于金属管体的至少一个敞口连接端且焊接连接于金属管体，金属衬套呈中空状且金属衬套的周壁上具有与外部管路相连接的螺纹；金属衬套的壁厚大于金属管体