| 摘要 |
<p>1512229 Cleaning pipes BROWN & ROOT Inc 30 Dec 1975 [22 Jan 1975] 53140/75 Headings F2N and F2P Submerged pipelines are purged of liquid by positioning at one end a "pig" launcher which sequentially propels pigs under compressed gas pressure into the pipeline and positioning at the other end of the pipeline a "pig" receiver in which the pigs are received and retained, the receiver having outlets to allow egress of the liquid being purged. As shown in Figs. 6, 7 the launcher comprises an inner tube 102 surrounded by a shroud 104, compressed gas being fed through pipes 116, 116<SP>1</SP>, 116<SP>11</SP> to the interior of the inner tube. As a pig leaves the launcher gas is expelled via pipe 138 to the surrounding water of some remote point to indicate the launch of the pig. As the pig approaches the receiver, Figs. 3, 4, the purged fluid is expelled via pipe 66. When the pig passes port 68 gas escapes via pipe 66 to indicate the arrival of the pig. Outlets 78 allow the pig to be urged to the end of the receiver where it is held by one of the seats 88. The apparatus may be used when laying pipelines and when it is necessary to expel the liquid contained therein, e.g. to bring the pipe to the surface for repair. The pig launches and receive may each be constructed to perform both functions so that purging may take place in either direction without having to recharge the launcher.</p> |
