Hydraulic liner releaser and release method for oil and gas wells

Abstract

The invention discloses a hydraulic liner releaser and a hydraulic liner release method for oil and gas wells. One end of a shell of the releaser of the invention is connected with a dual-male pup joint of a hanger in a sealed way, while the other end is connected with the pup joint of a liner in a sealed way; and one end of an insert pipe is connected with the pup joint of a drill stem in a sealed way, while the other end is connected with a locking mechanism which is arranged in the shell, a pressure transfer hole which leads to a hydraulic cylinder is formed on the insert pipe, and a release mechanism is arranged in the insert pipe. In the invention, the liner is placed in the well by adopting the resetting lock-connection control of a liner column and a drill column and the blockage control of the pressure transfer hole first; then the liner is released in a mode that the release mechanism releases the blockage under a hydraulic pressure to perform hanging operation and release the resetting lock; and finally the separation of the liner is determined by a method of extracting the drill column under a controlled pressure and observing the pressure change of the drill column. The hydraulic liner releaser and the hydraulic liner release method suitable for the construction of liner hanging and cementing of deep wells, ultra deep wells, inclined wells and horizontal wells are convenient to operate, safe and reliable and strengthen the use effect of a liner hanger.

Description

technical field [0001] The invention relates to an oil and gas well hydraulic liner release device and a release method, which are used for the release control of the oil and gas well cementing liner. Background technique [0002] In the prior art, more and more short liner suspension cementing methods within 500 meters are used in deep wells, ultra-deep wells, deviated wells, and horizontal wells of oil and gas wells. For example, Chinese Patent No. "200620138318.7" discloses a single-ball hydraulic breakaway liner hanger. Its application date is September 22, 2006, and its authorization announcement date is November 28, 2007. There is a liquid inlet hole between the center tube and the body of the hanger, and a channel for a movable rubber plug is formed between the outer cylinder and the body. The liquid inlet hole is connected with the channel of the movable rubber plug. It is connected with the fixing screw, and the circulation mechanism is connected with the setting m...

AI Technical Summary

Problems solved by technology

[0003] The existing tail pipe hanger and tail pipe release method mainly have the following disadvantages: 1. Since the liquid inlet hole of the hanger liquid cylinder is connected with the internal circulation channel, it is easy to block the liquid cylinder with slurry debris or the circulation pressure makes the liquid cylinder advance 2. In some wells, the phenomenon that the tailpipe is not separated when the drilling is pulled out in the later stage of construction, and the implementation of the suspension weight discrimination method is difficult to operate, and the additional cost is high. In order to obtain the weight of the tailpipe drill string And related data need to be tripped and tested in advance, which takes time and resources, and the construction quality is difficult to guarantee

3. Due to the short stern tube column and light weight, using the existing stern tube hanger can only rely on changes in the weight of the stern tube suspension and the number of rotations or torque changes to determine whether the stern tube release is successful, and mistakes often occur, especially It is very difficult to release and identify the liner in directional deviated wells, horizontal wells and complex wells

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