| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a method for slow cooling of a thick steel plate, by which production efficiency can be improved, and a method for manufacturing a thick steel plate, in which the method for slow cooling of a thick steel plate is used. <P>SOLUTION: In a method for slow cooling of a thick steel plate, when a first thick steel plate and a second thick steel plate can be piled, the piled first and second thick steel plates are subjected to piling slow cooling on a cooling bed, and if a residual hydrogen value of the first thick steel plate and/or the second thick steel plate exceeds a cracking critical hydrogen value after the completion of the piling slow cooling, the thick steel plates exceeding the cracking critical hydrogen value are moved outside a production line and the moved thick steel plates are piled to be subjected to slow cooling until the residual hydrogen value is decreased to the cracking critical hydrogen value or less, and when the first thick steel plate and the second thick steel plate cannot be piled, the first thick steel plate and the second thick steel plate are subjected to usual slow cooling on the cooling bed without piling the first thick steel plate and the second thick steel plate. A method for manufacturing a thick steel plate includes a step of slow cooling of a hot rolled thick steel plate using the method for slow cooling of a thick steel plate. <P>COPYRIGHT: (C)2013,JPO&INPIT</p> |
