Title:
METHOD FOR HOT-BENDING STEEL PIPE
Document Type and Number:
Japanese Patent JP2017064771
Kind Code:
A
Abstract:
PROBLEM TO BE SOLVED: To restrain zinc, copper and an alloy of them, which adhere to a surface of a steel pipe, from causing embrittlement during hot bending of the steel pipe.SOLUTION: A steel pipe, in which impurities including zinc and copper adhere to a surface, is heated to a temperature as high as or higher than a boiling point of the zinc, without being bent. Subsequently, the steel pipe is temporarily cooled. After that, the steel pipe is bent while being locally heated at a temperature as high as or higher than a temperature enabling quenching and lower than a melting point of the copper. The bent pipe is cooled and quenched.SELECTED DRAWING: Figure 3
Inventors:
SUZUMORI TOSHIO
NAGAYAMA YOSHIYUKI
NAGAYAMA YOSHIYUKI
Application Number:
JP2015196061A
Publication Date:
April 06, 2017
Filing Date:
October 01, 2015
Export Citation:
Assignee:
TOYOTA TEKKO KK
International Classes:
B21D7/16; C21D1/18; C21D9/08
Domestic Patent References:
| JPH07252594A | 1995-10-03 | |||
| JP2013252567A | 2013-12-19 | |||
| JPS617019A | 1986-01-13 | |||
| JP2015116575A | 2015-06-25 | |||
| JP2013091099A | 2013-05-16 | |||
| JP2013082979A | 2013-05-09 |
Foreign References:
| WO2015001705A1 | 2015-01-08 |
Attorney, Agent or Firm:
Okada International Patent Office
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