All-time drainage and prevention dual-purpose device for pumping well

Abstract

The invention discloses an all-time drainage and prevention dual-purpose device for a pumping well. The problem that an existing blowout prevention and oil drainage device can only work in a single time period is mainly solved. The device is characterized in that a valve body (5) is arranged outside a center pipe (1); a broken-line-shaped rail groove (12) is formed in the outer surface of the upper part of the center pipe (1); a rail nail (4) is arranged in the rail groove (12) and is connected to the valve body (5); a valve body liquid passing hole (17) is formed in the position, corresponding to a lower outer cylinder (7), on the side wall of the valve body (5); an upper liquid passing hole (13) and a lower liquid passing hole (16) are formed in the central pipe (1); a check valve (6) connected with one of the liquid passing holes is arranged on the valve body (5); and a spring (9) is arranged between the bottom end of the central pipe (1) and an inner boss (10) of the lower outer cylinder (7). The all-time drainage and prevention dual-purpose device for the pumping well not only has the functions of blowout prevention and oil drainage at the same time, but also can realize all-time blowout prevention and oil drainage of pump inspection operation.

Description

technical field [0001] The invention relates to the field of oil fields, in particular to a full-time drainage and prevention dual-purpose device for an oil pumping well. Background technique [0002] In pumping wells during pump inspection and pumping operations, for wells with high downhole pressure, liquid will be sprayed from the tubing to the ground. For wells with low downhole pressure, although the liquid cannot be sprayed upwards, since the pump is fixed and the valve is closed during the string lifting process, the well fluid in the tubing will be brought to the surface when the tubing string is pulled out. It not only pollutes the environment, but also deteriorates the working conditions of the workers, making the wellhead workers operate in oil pollution, and the well site needs to be cleaned after the construction is completed, which increases a lot of workload. For this reason, blowout prevention and oil drainage during oil well tripping operations are importan...

AI Technical Summary

Problems solved by technology

[0014] In summary, there are still various defects and problems in the existing various blowout prevention and oil drainage techniques: among them, the blowout prevention technique can only do One-way blowout prevention in the process of lifting and lowering the pipe string, or two-way blowout prevention in the process of lifting and lowering the pipe string, but it cannot prevent blowout when lifting the pipe string

There are also various defects and problems in the downhole tool for oil drainage: the rod-throwing type oil drainer can only be thrown after the rod string is lifted. If the rod column below the breakpoint remains in the oil pipe, the rod cannot be thrown; the oil drain that is opened by suppressing pressure, when the oil well is leaked and the pump is checked, cannot hold up the high pressure, and the oil drain will also fail. It cannot be opened, and it is cumbersome to operate because it needs to be loaded on the tanker and pump truck; the oil drainer that is opened by pulling requires additional anchoring tools or anchoring mechanisms, which is not only costly, but also cumbersome to operate, and also has time-consuming production. The oil drainer is held open when diagnosing the pump condition due to suffocation, or the risk of the anchoring mechanism getting stuck when the pipe string is lifted; the oil drainage process operated at the bottom of the pipe string needs to deepen the pipe string, adding additional The workload of pulling and transporting the lengthening tubing to the well site and the operation workload of lowering and deepening the tubing string

However, the downhole tools for blowout prevention and oil drainage must be connected to the pipe string to go up and down the well when the pump was run last time. When will the well need to check the pump next time, and how long will it take for the operation team to go up the well after the pump fails and shuts down? When the pump inspection operation is carried out, whether it should be blowout prevention or oil drainage at that time, whether the well should be equipped with blowout prevention tools or oil drainage tools on the pipe string during this operation, except for oil fields (or areas where the formation pressure is much lower than the hydrostatic column pressure) block) can be directly determined that it should be equipped with an oil drainer, which is really difficult to determine in many cases, so it is expected to have a downhole tool that can not only prevent blowout but also drain oil, so as to meet the environmental protection needs of different oil well conditions

[0016]In the existing literature, some people have also proposed the conversion of the blowout prevention and oil drainage functions based on the pressure difference between the inside and outside of the pipe. The conversion still depends on pulling out the sucker rod and then throwing the rod. In this way, the process can only work in part of the process of checking and lowering the pump operation. After the pole is pulled out, the production channel is open during the lifting of the pole, and the liquid can still be sprayed in the pipe during this working period

Second, the pump inspection operation in many wells is carried out due to the breakage of the rod string. The rod string below the breakpoint remains in the tubing and cannot be lifted out with the upper rod string. In this case, it is impossible to cast the rod before the string is lifted. If the production channel is closed, blowout prevention and oil drainage cannot be prevented when the string is lifted

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