| 摘要 |
<p>A device for internally butt-welding pipes (1), of the type comprising a support and guide frame (2) for an annular welding member rotatable coaxially to the pipes to be welded, and carrying a plurality of welding heads (4), the device comprising at least one sensor (15) connected to a unit for controlling the movement of said member and arranged to sense the presence of said heads at predetermined points. The sensor (15) comprises a first part (5) arranged to emit a signal and a second part (6) arranged to modify said signal, said two parts being provided respectively in seats (7) provided in said support and guide frame (2) and in said annular welding member (3) or vice versa, said two parts being arranged in such a manner as to remain permanently separated from each other.</p> |
