To provide a method of straightening an electric resistance welded steel pipe by which the twist angle of a weld bead part is fallen in a prescribed range when performing rotating straightening by advancing the pipe while rotating it with a pair of upper and lower rotating straightening rolls which are cross arranged to increase the straightness of the electric resistance welded pipe having approximately round cross section obtained by cutting into prescribed length after drawing and rolling in the temperature range of 400C to a transformation point Ac3.
In this method of straightening the electric resistance welded pipe, a cross angle formed by the axial centers of the pair of the upper and lower rotating straightening rolls is set to 90-105.
| WO/2003/097270 | FEEDING DUCT FOR A STRAIGHTENING MACHINE |
TAKEMURA YASUMASA
KAITA HIROSUKE
KAWABATA YOSHIKAZU
NAGAHAMA TAKUYA
SAKAGUCHI MASAYUKI
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