Blowout prevention valve for downhole operation

Abstract

An internal thread at the upper end of a shell is connected with a valve seat body, a reducing external thread at the upper end of the valve seat body is connected with an upper coupling, the upper end of the upper coupling is connected with a lifting pipe supporting cylinder, an internal thread at the lower end of the shell is connected with a lower joint, and the lower end of the lower joint is connected with an in-well tail pipe; a liquid passing channel is formed among the upper coupling, the valve seat body, the shell and the lower joint; an annular hole is formed in the radial face of the lower tail end of the valve seat body, an automatic valve plate system is hung on the annular hole, a switch connecting rod system is hung in the annular hole of the automatic valve plate system, the lower end of the switch connecting rod system is connected with a pushing bolt of an energy storage spring, and the lower end of the energy storage spring is connected with a spring protection hoop side hole formed in the shell. The blowout prevention valve is used in cooperation with the rod type oil well pump, well killing and blowout prevention are not carried out during oil well pump inspection operation, the rod type pump is adopted for lifting, a pipe column is not lifted, only a sucker rod column is lifted, time is saved during operation, ground pollution is prevented, cost is reduced, and the production time rate of the oil well is increased, cost is reduced, and efficiency is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of oil and gas well development, and relates to preventing blowout pollution during the operation of an oil production lifting pump in an oil well during oil field development, and particularly relates to a blowout preventer valve for downhole operations. Background Art

[0002] The rod pump is one of the traditional oil production methods in the petroleum industry, and it is also the dominant mechanical oil production lifting method in oil production engineering. More than 80% of the production wells in oil fields across the country use the rod pump lifting process.

[0003] As an important lifting equipment of the rod pumping system, the oil pump has a complex working environment and harsh conditions. It has the characteristics of simple structure, high strength, good quality, reliable sealing of the connection parts, good material wear resistance and corrosion resistance, and long service life. Although the downhole oil pump has the advantages of durability and long service life, it also has failure problems. Once the downhole oil pump has a problem, the pump must be replaced. Oil well operations must take measures to kill the well, prevent blowouts, and prevent ground pollution. These measures will pollute the formation and reduce production, and increase operating costs.

[0004] To solve this problem, the present invention aims to develop a downhole blowout preventer. Summary of the invention

[0005] The purpose of the present invention is to provide a blowout preventer for downhole operations in view of the defects and shortcomings of the prior art. The valve is used in conjunction with a rod-type oil pump. During the oil well inspection and pumping operation, the well is not pressed to prevent blowout. The rod-type pump is used to lift the lifting pipe string, but only the pumping rod string is lifted (the oil pump is lifted together with the rod string). The operation saves time, prevents ground pollution, and reduces costs, so as to improve the production time of the oil well, reduce costs and increase efficiency.

[0006] The present invention solves the technical problem by the following technical solutions:

[0007] A blowout preventer for downhole operations, comprising an upper coupling, a valve seat body, a shell and a lower joint connected in sequence from top to bottom, wherein the upper end of the shell is internally threadedly connected to the valve seat body, the upper end of the valve seat body is externally threadedly connected to the upper coupling, the upper end of the upper coupling is connected to a lifting pipe support tube, the lower end of the shell is internally threadedly connected to the lower joint, the lower end of the lower joint is connected to a tail pipe in the well, and a liquid passage is formed among the upper coupling, the valve seat body, the shell and the lower joint; an annular hole is provided on the radial surface of the lower end of the valve seat body, an automatic valve plate system is suspended on the annular hole, a switch connecting rod system is hung in the annular hole of the automatic valve plate system, the lower end of the switch connecting rod system is connected to a push bolt of an energy storage spring, and the lower end of the energy storage spring is connected to a spring guard hoop side hole provided in the shell.

[0008] Moreover, the lower end of the valve seat body is provided with a sealing spherical surface which matches with the upper end surface of the automatic valve plate.

[0009] Moreover, the outer diameter of the upper coupling is a smooth tube, and both ends of the inner diameter are standard 21 / 2 flat oil pipe female buckles.

[0010] Moreover, the valve seat body cooperates with the automatic valve plate to close the liquid passage. The upper end of the outer diameter of the valve seat body is provided with a standard 21 / 2 flat oil pipe male buckle connected to the upper coupling. The middle and lower part of the valve seat body is expanded and provided with an ordinary pipe male thread connected to the upper end of the inner diameter of the shell; the inner diameter of the valve seat body has the same diameter as the light hole.

[0011] Moreover, the automatic valve plate system is composed of a valve bracket, a valve plate, a suspension ring and a pin shaft. The bracket is used to suspend, position, fix and connect the valve seat body and the switch connecting rod system. The valve plate cooperates with the sealing spherical surface at the lower end of the valve seat body to achieve closing and unblocking the liquid passage in the pipe.

[0012] Moreover, the outer diameter of the shell is equal to that of a smooth tube, and both ends of the inner diameter are respectively provided with common female threads connected to the lower part of the valve seat body and the upper part of the lower joint.

[0013] Moreover, the upper outer diameter of the lower joint is provided with a common pipe male thread connected to the lower part of the shell, and the middle part is reduced in diameter and provided with a standard 21 / 2 flat oil pipe male thread connected to the tail pipe in the well, and the inner diameter is a smooth pipe.

[0014] The advantages and beneficial effects of the present invention are:

[0015] 1. The blowout preventer valve of the present invention is used in conjunction with a rod-type oil pump to prevent blowouts without suppressing the well during oil well inspection and pumping operations. The rod-type pump is used to lift the pipe string instead of the lifting string, and only the pumping rod string is lifted (the oil pump is lifted together with the rod string). The operation is time-saving, ground pollution is prevented, and costs are reduced, thereby improving the production time of oil wells, reducing costs and increasing efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a structural schematic diagram of the present invention.

[0017] Description of Reference Numerals

[0018] 1-upper coupling, 2-valve seat body, 3-automatic valve plate system, 4-switch connecting rod system, 5-energy storage spring, 6-housing, 7-lower joint. DETAILED DESCRIPTION

[0019] The present invention is further described in detail below through specific examples. The following examples are only illustrative and not restrictive, and the protection scope of the present invention cannot be limited thereto.

[0020] A blowout preventer for downhole operations, the innovation of which lies in: comprising an upper coupling 1, a valve seat body 2, a shell 6 and a lower joint 7 connected in sequence from top to bottom, the upper end of the shell 6 is internally threadedly connected to the valve seat body 2, the upper end of the valve seat body 1 is externally threadedly connected to the upper coupling 1, the upper end of the upper coupling 1 is connected to a lifting pipe support tube, the lower end of the shell 6 is internally threadedly connected to the lower joint 7, the lower end of the lower joint 7 is connected to a tail pipe in the well, and a liquid passage is formed among the upper coupling 1, the valve seat body 2, the shell 6 and the lower joint 7; an annular hole is provided on the radial surface of the lower end of the valve seat body 2, an automatic valve plate system 3 is suspended on the annular hole, a switch connecting rod system 4 is hung in the annular hole of the automatic valve plate system 3, the lower end of the switch connecting rod system 4 is connected to a push bolt of an energy storage spring 5, and the lower end of the energy storage spring 5 is connected to a spring guard hoop side hole provided in the shell 6.

[0021] The upper coupling (1) is designed to be connected to the bottom of the lifting pipe (pump hanging depth) support cylinder and the valve seat body (2) at the bottom. The outer diameter of the coupling is the inner diameter of the smooth pipe and both ends are standard 21 / 2 flat oil pipe female buckles.

[0022] The valve seat body (2) is designed to cooperate with the automatic valve plate system (3) to close the liquid passage in the pipe. The upper end of the outer diameter is provided with a standard 21 / 2 flat oil pipe male buckle connected to the upper coupling (1). After the middle and lower parts are expanded, they are provided with a common pipe male thread connected to the upper end of the inner diameter of the shell (6); the inner diameter has the same diameter as the smooth hole, but a spherical surface is provided at the lower end to cooperate with the upper end surface of the automatic valve plate system (3) for easy sealing. A ring hole for suspending the automatic valve plate system (3) is also designed on the radial surface of the lower end.

[0023] The automatic valve plate system (3) is designed to cooperate with the valve seat body (2) to close the liquid passage in the pipe, and it comprises a valve bracket, a valve plate, a suspension ring, and a pin shaft; the bracket is designed to suspend, position, fix (the valve plate), and connect the valve seat body (2) and the switch connecting rod system (4); the valve plate is designed to cooperate with the spherical surface sealed at the lower end of the valve seat body (2) to achieve closing and unblocking the liquid passage in the pipe.

[0024] The switch connecting rod system (4) is designed for automatically pushing and pulling the automatic valve plate system (3) to switch, and is connected to the ring hole below the switch end of the automatic valve plate system (3) at the top and connected to the push bolt on the upper part of the energy storage spring (5) at the bottom.

[0025] The energy storage spring (5) is an energy storage release spring designed to push the automatic valve plate system to close through the switch connecting rod system, and it is seated in the spring hoop side hole in the housing (6).

[0026] The housing (6) is designed to be connected to the valve seat body (2) at the top and the lower joint (7) at the bottom, and to protect the automatic valve plate system (3), the switch connecting rod system (4), and the energy storage spring (5) inside. The outer diameter is equal to the diameter of the light tube, and the two ends of the inner diameter are respectively provided with ordinary female threads connected to the lower part of the valve seat body (2) and the upper part of the lower joint (7). The rest are internal light tubes. The middle part of the body is provided with a screw hole for fixing and positioning the top thread of the spring protection hoop.

[0027] The lower joint (7) is designed to be connected to the housing (6) at the top and the tail pipe in the well at the bottom, and to hold up the spring protection hoop inside. The upper part of the outer diameter is provided with a common pipe male thread connected to the lower part of the housing (6), and the middle part is provided with a standard 21 / 2 flat oil pipe male thread connected to the tail pipe in the well after the diameter is reduced, and the inner diameter is a smooth pipe.

[0028] The working principle of the present invention is:

[0029] According to the design of the pump hanging depth of the completion lifting pipe column, the blowout preventer of the present invention is connected to the lower end of the support tube and then lowered into the well. After the sucker rod column is lowered (the lower end of the rod column is connected to the rod-type sucker pump, the liquid inlet screen pipe under the pump is inserted into the valve seat body (2), the automatic valve plate system (3) is opened to allow liquid to enter the pipe, and the wellhead Christmas tree is tested for pressure and qualified, and then the well is handed over for pumping and production.

[0030] The blowout preventer of the present invention is used in conjunction with a rod-type oil pump. During the oil well inspection and pumping operation, the well is not pressed to prevent blowout. The rod-type pump is used to lift the pipe string instead of the lifting string. Only the pumping rod string is lifted and lowered (the oil pump is lifted and lowered together with the rod string). The operation is time-saving, ground pollution is prevented, and costs are reduced, thereby improving the production time of the oil well, reducing costs and increasing efficiency.

[0031] Although the embodiments and drawings of the present invention are disclosed for illustrative purposes, those skilled in the art will appreciate that various substitutions, changes and modifications are possible without departing from the spirit and scope of the present invention and the appended claims. Therefore, the scope of the present invention is not limited to the contents disclosed in the embodiments and drawings.

Claims

1. A blowout preventer valve for underground operation, characterized in that: The invention comprises an upper coupling (1), a valve seat body (2), a shell (6) and a lower joint (7) which are connected in sequence from top to bottom, wherein the upper end of the shell (6) is internally threadedly connected to the valve seat body (2), the upper end of the valve seat body (1) is externally threadedly connected to the upper coupling (1), the upper end of the upper coupling (1) is connected to the lifting pipe support tube, the lower end of the shell (6) is internally threadedly connected to the lower joint (7), the lower end of the lower joint (7) is connected to the tail pipe in the well, and the upper coupling (1) is connected to the lifting pipe support tube. A liquid passage is formed between the hoop (1), the valve seat body (2), the shell (6) and the lower joint (7); a ring hole is provided on the radial surface of the lower end of the valve seat body (2), an automatic valve plate system (3) is suspended on the ring hole, a switch connecting rod system (4) is hung in the ring hole of the automatic valve plate system (3), the lower end of the switch connecting rod system (4) is connected to the push bolt of the energy storage spring (5), and the lower end of the energy storage spring (5) is connected to the spring hoop side hole provided in the shell (6).

2. The blowout preventer for underground operation according to claim 1, characterized in that: The lower end of the valve seat body (2) is provided with a sealing spherical surface which matches with the upper end surface of the automatic valve plate system (3).

3. The blowout preventer for underground operation according to claim 1, characterized in that: The outer diameter of the upper coupling (1) is a smooth tube, and the inner diameter ends are standard 21 / 2 flat oil pipe female buckles.

4. The blowout preventer for underground operation according to claim 1, characterized in that: The valve seat body (2) cooperates with the automatic valve plate system (3) to close the liquid passage. The upper end of the outer diameter of the valve seat body (2) is provided with a standard 21 / 2 flat oil pipe male buckle connected to the upper coupling (1). The middle and lower part of the valve seat body (2) is expanded and provided with a common pipe male thread connected to the upper end of the inner diameter of the shell (6); the inner diameter of the valve seat body (2) has the same diameter as the light hole.

5. The blowout preventer for underground operation according to claim 1, characterized in that: The automatic valve plate system (3) is composed of a valve bracket, a valve plate, a suspension ring and a pin shaft. The bracket is used to suspend, position, fix and connect the valve seat body (2) and the switch connecting rod system (4). The valve plate cooperates with the sealing spherical surface at the lower end of the valve seat body (2) to achieve closing and unblocking the liquid passage in the pipe.

6. The blowout preventer for underground operation according to claim 1, characterized in that: The outer diameter of the shell (6) is equal to that of a plain tube, and both ends of the inner diameter are provided with common female threads connected to the lower part of the valve seat body (2) and the upper part of the lower joint (7).

7. The blowout preventer for underground operation according to claim 1, characterized in that: The upper outer diameter of the lower joint (7) is provided with a common pipe male thread connected to the lower part of the (6) shell, and the middle part is reduced in diameter and provided with a standard 21 / 2 flat oil pipe male thread connected to the tail pipe in the well, and the inner diameter is a smooth pipe.

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