| 摘要 |
PURPOSE:To achieve square processing for sizing of thick and large sized square material with less number of rolling stages, by providing one or more stages of a material feeding sizing rolls of square steel pipe and providing a plurality of stages of finish sizing rolls. CONSTITUTION:Upper and lower rolls 10 and 11 of a material feeding sizing rolls are constituted so that the flange F and the corner C of a square steel pipe material A1 can be pressed, and left and right rolls 12 and 13 are not driven and they are arranged to retain the flange. That is, the upper and lower rolls 10 and 11 are constituted to have a rising height H of the flange including a corss point S of mother pipe material deformation. Next, the upper and lower rolls 15 and 16 of the finish sizing roll and left and right nondriven rolls 17 and 18 are arranged, which can be converted with conventional finish sizing rolls. |
