| 摘要 |
<p>1460216 Pipeline pig; detecting and repairing leaks in pipes EXXON PRODUCTION RESEARCH CO 31 Oct 1974 [5 Nov 1973] 47156/74 Headings F2P and F2N A pig of the type adapted for one way pipeline travel has a body 52 slidably supporting at least one sealing cup 26, 27 each having a forwardly extending lip portion, and is further characterized by the inclusion of anchor means 56, 57 positioned on the body member and movable therewith, whereby the anchor means, upon application of a pressure differential in the opposite direction to travel urges the sealing cup lips into contact with the pipe wall effecting anchorage of the pig relative to the pipeline. As shown anchor means comprising flanged discs 56, 57 are fixedly attached to the body 52 forming a unit which is slidable according to the direction of the applied pressure differential between the position shown, in which the pig is adapted for propulsion, and an anchorage position wherein rims 56B, 57B of the flanged disc member engage tapered lips 32, 33 of the sealing cups 26, 27 to effect anchorage via the resulting wedging action against the pipeline wall. Sealing cups 26, 27 are formed of a resilient material, e.g. natural or synthetic rubber, polyurethane and are supported by, and attached to, rigid (e.g. metal) discs 28, 29, to form support means wherein openings 59, 60 are formed to provide fluid bypass. The pig has use in marine pipe recovery, and has further application in detecting leaks in such piping. In the latter case the pig is progressively propelled by forward pressure application to points along the pipeline at each of which anchoring by reverse pressure application allows testing of the pipe section so defined for ability to sustain the applied pressure; which procedure is repeated at further points along the pipeline until pressure fall off, i.e. a leak, is detected.</p> |
