| 摘要 |
<p>A method is described for handling of a first pig (20) that has become trapped inside a pipeline (10), in that inserted into the pipeline is a second pig (30) which is led up to and adjoining the pig and blocks flow of fluid through the pipeline, as pressuring upstream of the second pig (30) can loosen the first pig so that it can be collected, while when the pig is still trapped, the position of the first pig in the pipeline is determined so that it can be brought up. The method is characterised in that a pig in the form of a channel-forming (50) casing body that incorporates a removable blocking element (32) which blocks the flow of fluid through the channel (50) is inserted into the pipeline, and if the pig does not become loose, said pig position is determined by an itself known way, and the blocking element is removed to open for flow of fluid through the channel of the pig. An especially preferred pig construction is also described.</p> |
