PREHEATING DEVICE AND PREHEATING METHOD IN COLD STRAIGHTENING

摘要

PROBLEM TO BE SOLVED: To provide a preheating device with which straightening effect is improved by preliminarily partially executing preheat treatment of prescribed parts of a metallic material and which is especially effective to the straightening of partial strain and method thereof. ;SOLUTION: This device is for heating plural arbitary places in the width direction of the upper-surface side and/or under-surface side of the metallic material to be threaded, heating is adjustable by heating amount adjusting means which are respectively independently provided and on-off of heating is enabled by elevating/lowering means for respectively integrally elevating and lowering the upper-surface side and/or under-surface side.;COPYRIGHT: (C)1999,JPO