| 摘要 |
PCT No. PCT/AU95/00667 Sec. 371 Date Apr. 3, 1997 Sec. 102(e) Date Apr. 3, 1997 PCT Filed Oct. 6, 1995 PCT Pub. No. WO96/11324 PCT Pub. Date Apr. 18, 1996Apparatus adapted for movement through a passage (16) formed in the ground, comprising an elongate element (13) and means for positioning a shroud (20) around at least part of the longitudinal periphery of the elongate element for engagement against the periphery of the passage (16) to provide a space through which the elongate element can move, the shroud (20) being of flexible construction and being arranged to be progressively installed in position as the elongate element (13) moves along the passage, and means for introducing an inflation fluid into the region (90) between the shroud (20) and the elongate element (13) for inflating the shroud (20) and maintaining it in engagement against the periphery of the passage (16). |
