Recyclable blanking plug in oil tubing

Abstract

The invention relates to the technical field of a blanking plug device in an oil tube and provides a recyclable blanking plug in the oil tube. The recyclable blanking plug comprises a back off sub, a fishing head, an unsetting mandrel, an upper slips barrel, a rubber packer mandrel, a lower slips seat, a lower joint, a lower mandrel and a locking pawl, wherein an upper mounting shaft cavity opening downwards is formed in the back off sub; the fishing head is arranged in the upper mounting shaft cavity in a sleeving manner, and the inner wall of the lower part of the fishing head is fixedly mounted together with the outer wall of the upper part of the unsetting mandrel; long shaft holes are formed uniformly in the circumference of the upper part of the unsetting mandrel. The blanking plug is reasonable and compact in structure and convenient to use, a steel wire running tool is used during setting and unsetting, and setting and unsetting operation is simple and feasible, larger gripping force can be provided under the condition that good plugging is guaranteed, the plug does not move after plugging, and sealing is guaranteed; meanwhile, the plug can be recycled after unsetting, can perform setting in any position in the oil tube, the plugging pressure is high, various working condition requirements are met, and the cost is reduced effectively.

Description

technical field [0001] The invention relates to the technical field of plugging devices in oil pipes, and relates to a recoverable plugging device in oil pipes. Background technique [0002] During the workover process of oil and gas wells, the pipe string must be tripped frequently. In order to prevent blowout, well control equipment must be installed. When overflow or blowout occurs, the annulus can be shut down remotely and instantaneously. However, some blowouts also occur in In the pipe string, since the tubing is connected with a fine thread, it is sometimes difficult to install the wellhead cock after overflow occurs, resulting in a blowout accident. Especially in the construction of carbonate reservoirs, the workover is often carried out under the state of continuous loss of well killing fluid. In order to balance the formation pressure, most of the "hanging tank" method is used. For well technicians, especially in deep well construction, it often takes a long time ...

AI Technical Summary

Problems solved by technology

[0003] The present invention provides a retrievable oil pipe internal plug, which overcomes the above-mentioned deficiencies in the prior art, and can effectively solve the problems of the existing oil pipe internal plug which is cumbersome to operate, requires special tools when running in, and cannot be recovered after being installed. The problem of high operating costs