| 摘要 |
<p>A tension ring lifting assembly (1) for applying an upwards tension to a pipe has a plurality of collar segments (14, 16) that are assembled into a ring around the pipe, and a plurality of slip segments (4) adapted to fit between the collar segments and the pipe. The collar segments (14, 16) are held together by means (11, 12, 13) for tensioning adjacent collar segments against one another to secure the ring around the pipe. The slip segments (4) have an arcuate inner face (5) adapted to make direct contact with an outer surface of the pipe. The collar segments and the slip segments when assembled have inclined mutually contacting surfaces (9, 19) such that an inner diameter across the assembled ring, between the inner faces (5) of the slip segments (4), varies as the slip segments move up and down inside the assembled collar segments (14, 16). Each slip segment has a main body (15) and a plurality of elongate vertically extending die inserts (17), each die insert being removably fitted to the main body and having on the radially inner face a granular particle gripping surface (22) for gripping the outer surface of the pipe. The main body (15) has a plurality of vertically extending die insert channels (41 ) that hold the die segments, each channel having an open end (42) that is closed by a retaining plate (18) removably fixed to each collar segment (14, 16).</p> |
