| 摘要 |
PURPOSE:To obtain a titled device capable of releasing a mandrel bar in case of emergency by turning a pusher for pushing a mandrel bar from its backside, together with a crank lever for press holding the bar from its upper side, to the releasing positions by a hydraulic cylinder. CONSTITUTION:In a retaining device 10 of continuous pipe rolling mill, where the large diametral part M2 at the rear end of a mandrel bar M, inserted into a hollow pipe to project its both ends from the pipe, is pushed from its backside by a pusher 50, and at the same time, the small diametral part M1 at the rear end of the bar M is held from its upper side by a crank lever 5, to constrain the bar M; a roller 41 at the lower end of a lever 40 runs onto a cam 43 to turn levers 40, 38, and also it turns a crank lever 15 through a lever 13 and a link 14, to release the constraint of the bar M when the rolling of the hollow pipe is finished. In an emergency such as a seizure is generated between the hollow pipe and the bar M, a lever 38 is turned through a lever 55 to forcibly release the constraint to the state before the engagement of the roller 41 with the cam 43 by extending a hydraulic cylinder 56 of a driving device used for releasing emergency. |
