| 摘要 |
PURPOSE:To improve dimensional accuracy in rolling and to suppress the generation of noise during rolling by fixing a plug bar supported to a thrust carriage to the carriage and supporting rotatably the plug at the top end of the plug bar thereby suppressing the oscillation of the plug. CONSTITUTION:A plug bar 12 is fixed to the front surface of a thrust carriage 11, and a detaining ball 15 energized radially by a compression spring 14 is provided to the top end of the bar 12. The ball is engaged and disengaged in the recess 17 on the inside peripheral surface of the plug 16, by which the plug 16 can be attached and detached to and from the top end of the bar 12. A thrust rolling bearing 20 is interposed between the supporting seat 18 in the part for supporting the plug 16 in the axial direction of the top end of the bar 12 and the end face 19 of the plug 16. Then the rotation and rolling thrust are given to the plug 16 in the stage of rolling a billet, but the plug 16 rotates in following-up smoothly on the rotation of the billet, thus preventing the generation of the biting defect. Since the bar 12 does not rotate, the generation of oscillation of the plug 16 and the generation of impact noise that arise from the rolling of the bar 12 are suppressed. |
