| 摘要 |
<p>PROBLEM TO BE SOLVED: To reduce an end product cost by improving a material yield, and to improve reliability by reducing the occurrence of the defective seal function of a seal part. SOLUTION: A cylindrical socket part 1 and a cylindrical nipple part positioned at the internal part of the socket part are arranged on one end side, and a screw part in which a joint member is screwed, a communicating hole to communicate the hollow part of the nipple part to the screw part, and a seal part formed at the opening edge part of the communication hole are arranged on the other end part side. Manufacturing method of this metal fitting for a hose comprises a first process wherein an intermediate molded product having a cylindrical part 11 corresponding to a socket part, a protrusion part 12 corresponding to the nipple part, a part (an inner surface 13) corresponding to a screw part, and a part (a truncated part 16) corresponding to a seal part 6 is manufactured through plastic working; a second process wherein heat treatment to relax work hardening occurring to the intermediate molded product is applied on the intermediate molded product; and a third process wherein plastic working is applied on the intermediate molded product to manufacture a metal fitting for a hose being a final product.</p> |
