Production of a double pipe used in an air conditioner comprises inserting a straight inner pipe into a straight outer pipe so that they are positioned at a predetermined relative position and further processing

摘要

Production of a double pipe comprises forming a straight inner pipe (162) having a predetermined length, forming a straight outer pipe (161) having a diameter larger than the diameter of the inner pipe, inserting the inner pipe into the outer pipe so that they are positioned at a predetermined relative position, fixing a first end section (161a1) of the outer pipe on the inner pipe to form a first fixing section, simultaneously bending the outer pipe and the inner pipe at the predetermined section after fixing the first end section to form a curved section (160b1) and fixing a second end section of the outer pipe after bending to form a second fixing section (160a2). Preferred Features: During fixing of the first end section of the outer pipe the first end section of the outer pipe is radially tapered and fixed to the inner pipe.