| 摘要 |
PURPOSE:To cut an I-beam into T-beam reduced in warpage and twist by making an intruded step in the web part and punching this step part. CONSTITUTION:The I-beam 20 is passed through a 1st slitter which are provided with a projecting roll 1 having a projecting cutter edge and a recessed roll 2 having a grooved (recessed) cutter edge which is opposed to that projecting cutter edge. The step which consists of a recessed groove which is made on a face in the web part of the shape and projected line which is made on the other face opposing to the groove with these rolls is formed. Next the I-beam 20 is passed through a 2nd slitter which is provided with a projecting roll 10 and recessed roll 11 which are inversely constituted to the 1st slitter. And the intruded step part is cut so as to be punched by bringing the projecting cutter edge of the projecting roll 10 into contact with the projected line in the web part and bringing the cutter edge of the recessed roll 11 into contact with the recessed groove. In this way, the T-beam which hardly requires correction is easily manufactured. |
