| 摘要 |
A tube assembly is formed by placing a sleeve member over an end portion of a tube and then placing the tube and sleeve in a die. A movable punch is then pressed against a projecting end portion of the tube thereby forming a radially extending double upset flange integrally with the sleeve member. The sleeve member has contact surfaces against which a substantial portion of the radially extending double upset flange conforms. A portion of the outer surface of the tube, and the entire surface of a compound curved fillet extending from the outer surface of the tube to a radially outwardly extending surface of the flange also conform to the sleeve member. |
