| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a manufacturing method for manufacturing a short tube having a tapered surface of a force-fitting chamfer from a hoop material. SOLUTION: A hoop material 1A is set to an uncoiler, the stress of a coil is removed through a leveler, and a tapered surface 2a1 equivalent to a force-fitting chamfer is plastically deformed in either surface of the upper surface or rear surface of the width part of the hoop material 1A. An excess part of the plastically deformed place is notched and cut at the length 2b1 wherein undecided width parts 2b2, 2c2 are left from the prepared length in the radial direction of a short tube. Further, a blank 2A is made by being cut at the prepared length, next the orthogonal direction of the taper is bent into a cylindrical body, the undecided width parts 2b2, 2c2 are clamped with a jig and positioned, an abutted place is welded by laser beams, and the bead part by the laser beam welding is finished up. Next, after the undecided width parts 2b2, 2c2 are press cut so as to coincide with the end surface of the cylindrical body, the inside and outside are cleaned, the end surface part and the cylindrical part are straightened by a die, and the whole processes are completed. Thus, the short tube is manufactured from the hoop material through such a series of manufacturing method.</p> |
