To provide a working method which can inhibit a welded part at a pipe end from being cracked, when forming a reduced diameter portion by abutting a working roller on an end part of a welded pipe of ferritic stainless steel.
When forming the reduced diameter portion of which the diameter is gradually reduced toward the end part of the welded pipe to be worked, by using the working roller that is arranged on the outer periphery of the welded pipe made from the ferritic stainless steel as a base material and relatively revolves around the pipe, and by moving the working roller back and forth in the axial direction while moving the roller in the radial direction of the welded pipe to be worked, this working method includes: fixing the welded pipe to be worked; and revolving the working roller around the welded pipe to be worked, while spraying a refrigerant onto the welded zone of the welded pipe to be worked and cooling the welded zone.
COPYRIGHT: (C)2009,JPO&INPIT
Akihiro Ando
Atsushi Kurobe
| JP2003334626A | ||||
| JP2006291294A | ||||
| JP2004243354A |
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