HEAT-TREATMENT METHOD AND HEAT-TREATMENT FACILITY FOR STEEL PIPE

摘要

PPROBLEM TO BE SOLVED: To provide a heat-treatment method and a heat-treatment facility for steel pipe with which the heat-treatment can uniformly be performed without causing deformation, such as warping, in the whole steel pipe, and there is no fear of causing trouble due to infiltration of cooling water into the inside of the steel pipe. PSOLUTION: While rotating the steel pipe P by the plurality of rollers 2 arranged while having a falling gradient, the steel pipe is shifted in the inner parts of an induction heater 3, a holding furnace 4 and a cooling device 5, and is subjected to the heat-treatment of raising a temperature, holding the temperature and rapid cooling. The infiltration of the cooling water into the inner part of the steel pipe P is restrained by forming the falling gradient of 3-6 on a conveyance route 1, and the uniform heat-treatment can be performed. PCOPYRIGHT: (C)2011,JPO&INPIT