FIELD: jointing by welding tubes of different metals, particularly tubular adaptors aluminum alloy - stainless steel. SUBSTANCE: intermediate layer of adaptor is made in the form of sleeve of titanium alloy. One end of said sleeve is lap jointed by diffusion welding with sleeve of stainless steel; its other end is lap jointed with sleeve of aluminum alloy by welding-soldering process. Zones of diffusion welding and welding-soldering joints are mutually spaced by distance no more than 10 mm. Joint of sleeve of titanium alloy with sleeve of stainless steel may be made as male part and joint of titanium alloy sleeve with aluminum alloy sleeve may be made as female part. Length of lap joint of aluminum alloy sleeve with titanium alloy sleeve is no less than three thickness values of walls of sleeve of aluminum alloy. Length of lap joint of titanium alloy sleeve with stainless steel sleeve is no less than 15 mm. EFFECT: improved design of adaptor providing its increased strength. 4 cl, 1 dwg, 1 ex
