| 摘要 |
<p>A method and device for positioning a power tong (2) at the pipe joint (14) of a pipe string (12), where, after the pipe joint (14) has been brought within the working area of the power tong (2), the power tong (2) must be displaced to a position that corresponds with that of the pipe joint (14), and where a camera (16) which may be displaced in parallel with the pipe (12), and which is linked to a display (18), is displaced until the image of the pipe joint (14) coincides with a marker (40) in the display, whereupon a signal is transmitted to a control (26), indicating that the power tong (2) is to be displaced to a position that corresponds with that of the camera (16) and thereby that of the pipe joint (14).</p> |
