| 摘要 |
<p>The device has a memory device (3) to store rotational moment exercised on the device during opening and closing of the device, and formed by highly adjustable and rotatably supported rings arranged one over the other. An inner pipe has an external thread and a covering pipe has an internal thread, where a pipeline has a key post and is equipped with a status display displaying an opening condition of an underground pipeline armature.</p> |
