Design of flexible fixture used for plugging the perforations in oil and gas pipelines

In the long running process of oil and gas pipelines, the accidents of sudden perforation leakage inevitably happen to the pipelines due to the influence of unpredictable factors, such as natural and artificial factors. In order to minimize the loss caused by the accidents, a flexible fixture used for temporarily plugging the pipeline micro-leakage under slightly positive pressure was developed in this paper based on the fast tightening and binding characteristics of soft straps, combined with the compression sealing principle of the rubber pieces. Compared with rigid clamps, flexible fixtures are more advantageous with light weight, deformable property, non-stripping anti corrosion coating, low cost and quick installation. If the pipeline which has been temporarily plugged is equipped with the protruding sleeve steel pipe fittings, its permanent repair will be realized rapidly at low cost. In addition, dynamic plugging tests were carried out on the flexible fixture at the test bench. It is shown that the flexible fixture is characterized by convenient installation, high bearing capacity, safety and reliability. The research results provide the powerful support for the low-cost, safe and rapid maintenance and emergency repair of oil and gas pipeline leakage.