| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a piping coupling having a high coupling force between a piping and a flange member through pipe expansion. SOLUTION: A piping coupling comprises a coupling base member 30 having the opening part 32 of a refrigerant passage 31, a piping 10 having a first pipe expansion part 11 inserted in the opening part 32, and a flange member 20 fixing the piping 10 at a coupling base member 30. The piping 10 is inserted in the mounting hole 22 of a flange member 20, and a second pipe expansion part 14 press-contacted with the inner peripheral surface of the mounting hole 22 is formed by expansion of the piping 10 through insertion of a pipe expansion punch in the piping 10. An expansion part 15 is formed through contact-bonding of it to the end face 20b of the flange member 20 through expansion of the second expansion pipe from the outer peripheral surface of the piping 10 during expansion of the second pipe expansion part 14.</p> |
