| 摘要 |
PURPOSE:To remarkably reduce the time intervals of piercing a steel material and to improve the production efficiency of a seamless pipe, by improving a method for inserting and drawing out of a plug bar of a steel pipe piercer in manufactureing a seamless steel pipe. CONSTITUTION:A billet to be manufactured into a seamless steel pipe is pierced to form a hollow blank pipe 3 by operating a plug bar 7, forming rolls 2, and a billet pusher 1, and the blank pipe 3 with the plug bar 7 kept in an inserted state is transferred onto a skid 8. Next, the pipe 3 having the bar 7 inserted is pulled to the left side by a drawing block 11. The pipe 3 is forcedly stopped by a stopper 10, and only the bar 7 is drawn out from the pipe 3. The pipe 3 is carried out to the E direction by a transfer 15, and the bar 7 is transferred from a skid 31 to the F' direction by a transfer 16 to be fed to a piercing line again by a feeding conveyor 17. Thus, the time intervals of piercing a seamless steel pipe are reduced by circulating the bar 7 in a short time, and the production efficiency is improved. |
