Title:
曲がり矯正方法
Document Type and Number:
Japanese Patent JP7036215
Kind Code:
B2
Abstract:
There is provided a method for bend straightening in which a steel pipe having a bend is placed in a state where the steel pipe is convex upward, the steel pipe is pressed from above by a press unit at a target load value, whereby the steel pipe is straightened, the method including: (a) a step of measuring a bottom-dead-center load value Pk when the press unit is at a bottom dead center in the pressing; (b) a step of measuring an amount of change Δδ in amount of bend between an amount of bend of the steel pipe before the pressing in the step (a) and an amount of bend of the steel pipe after the pressing in the step (a); (c) a step of repeating the step (a) and the step (b) a plurality of times to create a relational expression Pk = f(Δδ); and (d) a step of determining a target load value for next pressing from the relational expression Pk = f(Δδ).
Inventors:
Koichi Kuroda
Shuji Otao
Shuji Otao
Application Number:
JP2020535814A
Publication Date:
March 15, 2022
Filing Date:
August 06, 2019
Export Citation:
Assignee:
Nippon Steel Corporation
International Classes:
B21D3/10
Domestic Patent References:
| JP2192820A | ||||
| JP49130303A | ||||
| JP63144822A | ||||
| JP63199026A |
Attorney, Agent or Firm:
Patents corporation Blitas