Quality control method of steel pipe which is an object to be heat-treated material and heat treatment method

摘要

PROBLEM TO BE SOLVED: To provide a heat treatment method which appropriately control the quality of every single material to be heat-treated while increasing the efficiency of the heat treatment, and to provide a method for controlling the quality of the material to be heat-treated.;SOLUTION: This heat treatment method comprises the steps of: setting a furnace temperature in a charging side of a heat treatment furnace 100 to a higher temperature than that in an extraction side; predicting a temperature-rising process of each material to be heat-treated by thermal transfer calculation; predicting a soaking period of time by calculation; when the predicted soaking periods of time include a shorter period of time than a target soaking time, predicting such an optimal transportation speed that the predicted soaking periods of time for all the materials to be heat-treated can be longer than the target soaking period of time by calculation; predicting the maximum temperature of the respective materials to be heat-treated by calculation; when the predicted maximum temperatures include a temperature higher than a target soaking temperature, calculating such an optimal set furnace temperature in the charging side that the predicted maximum temperature for all the materials to be heat-treated can be lower than the target soaking temperature; setting the optimal transportation speed and the optimal set furnace temperature as conditions in operating the heat treating furnace; and heat-treating the material.;COPYRIGHT: (C)2007,JPO&INPIT