Oil well blowout prevention gas collecting valve made of soluble material and using method of oil well blowout prevention gas collecting valve

Abstract

The invention discloses an oil well blowout prevention gas collecting valve adopting soluble materials and a using method, the gas collecting valve is a main body structure of a valve body formed by an upper connector and a lower connector, the outer side wall of the upper connector is connected with a shell, the inner wall of the shell is connected with a valve element metal framework, and the valve element metal framework is connected with a rubber valve element; the inner wall of the valve element metal framework is connected with the outer wall of the lower connector. An exhaust port and an air inlet are formed in the connecting position of the upper connector and the valve element metal framework and the connecting position of the shell and the valve element metal framework respectively, an exhaust channel is defined by the upper connector, the lower connector, the valve element metal framework, the rubber valve element and the shell, and a soluble sealing ring for blocking the exhaust channel is arranged in the exhaust channel. The method comprises the steps that after the soluble sealing ring is installed at a designated position, the gas collecting valve is put into a well, after the soluble sealing ring is dissolved, the exhaust channel is opened, and opening and closing of the gas collecting channel are achieved through contraction and recovery of the rubber valve element. The problem that in the prior art, when the well mouth pressure building risk is high, the gas collecting valve still needs to be manually opened through manual secondary well ascending operation is solved.

Description

Technical Field

[0001] This invention belongs to the field of associated gas recovery technology in oilfield downholes, specifically relating to an oil well blowout prevention gas gathering valve using soluble materials. This invention also relates to the method of using the above-mentioned gas gathering valve. Background Technology

[0002] Currently, associated gas recovery at oil wellheads in China mainly employs two methods: laying surface gas gathering pipelines and installing gas gathering valves at the wellhead for co-transportation with the oil gathering pipeline. The surface gas gathering pipeline method is suitable for oilfields with large gas volumes and high pressures. However, laying such pipelines is limited by high construction costs and terrain constraints, making it unsuitable for complex hilly and mountainous areas. The co-transportation method involves installing a surface gas gathering valve on the oil gathering manifold, drawing gas from the wellhead casing head to the gas gathering valve inlet via a high-pressure hose. When the associated gas pressure in the casing exceeds the back pressure of the oil pipeline, the surface gas gathering valve opens, allowing the associated gas to enter the oil gathering pipeline, resulting in co-transportation of oil and gas.

[0003] Furthermore, the gas gathering valve cores mostly use steel valve balls and valve seats, but due to the low ambient temperature in winter and the rapid release and heat absorption of associated gas, problems such as condensation blockage, valve freezing, and failure often occur in the gas gathering pipeline during winter. In addition, well workover operations require the removal and installation of surface gas gathering pipelines, and the large number of connecting threads, seals, high-pressure hoses, etc., pose leakage risks and safety and environmental hazards.

[0004] To address these issues, current technologies employ sliding-sleeve mechanical blowout prevention gas gathering valves for associated gas recovery. However, the operation of these valves requires waiting until the well is in normal production before using a pressure build-up process at the wellhead tubing to create a positive pressure differential between the tubing and the casing. This process opens the sliding-sleeve mechanism. Since some newly commissioned wells have relatively high casing pressure, opening the gas gathering valve requires even higher tubing pressure build-up, posing a risk of well pressure build-up. Furthermore, the opening operation requires technicians to return to the well after production has stabilized, increasing workload. Additionally, the initial production phase of new wells may involve the release of fracturing sand, which can cause sand jamming in the sliding-sleeve mechanism and malfunction of the sliding-sleeve pressure control switch. Summary of the Invention

[0005] The purpose of this invention is to provide an oil well blowout prevention gas gathering valve using soluble materials, which solves the problem in the prior art that when the risk of wellhead pressure buildup is high, the gas gathering valve still requires manual operation by going up to the well to open it.

[0006] Another object of the present invention is to provide a method for using an oil well blowout prevention gas collection valve made of soluble materials.

[0007] The first technical solution adopted in this invention is an oil well blowout prevention gas collection valve made of soluble material, including an upper connector, the lower end of which is connected to a lower connector to form the main structure of the valve body, a shell is connected to the outer side wall of the upper connector by threads, a valve core metal skeleton is connected to the inner wall of the shell near the lower connector, a rubber valve core is connected to the valve core metal skeleton, and the inner wall of the valve core metal skeleton is connected to the outer wall of the lower connector.

[0008] The upper connector pipe wall is provided with several sets of exhaust ports, and the connection between the shell and the valve core metal skeleton is provided with several sets of air inlets. The upper connector, lower connector, valve core metal skeleton, rubber valve core, and shell together form an exhaust channel that connects the air inlets and exhaust ports. A soluble sealing ring is provided near the exhaust port in the exhaust channel, and the soluble sealing ring blocks the connection between the air inlets and exhaust ports.

[0009] The first technical solution of the present invention is further characterized in that,

[0010] The soluble sealing ring is located at the annular end face formed by the inner side of the housing and the outer side of the upper connector.

[0011] The soluble sealing ring is made of soluble magnesium-aluminum alloy or soluble rubber material.

[0012] The rubber valve core is connected to the valve core metal skeleton through a vulcanization process to form an integrated structure.

[0013] The rubber valve core is press-fitted to the inner wall of the housing to form an annular shrink sealing surface, and the upper and lower spaces of the sealing surface are connected to the exhaust port and the air inlet port, respectively.

[0014] The end where the metal frame of the valve core connects to the rubber valve core is provided with several sets of rack and pinion structures.

[0015] A first sealing ring is provided at the connection between the housing and the upper connector;

[0016] A second sealing ring is provided at the connection between the upper and lower connectors;

[0017] A third sealing ring is provided at the connection between the valve core metal skeleton and the lower connector.

[0018] The upper connector is connected to the oil pipe hanger via threads, and the lower connector is connected to the oil pipe string via threads. The internal diameter of the valve body formed by the connection of the upper and lower connectors is consistent with and connected to the inner diameter of the oil pipe.

[0019] The second technical solution adopted in this invention is that the method of using the oil well blowout prevention gas gathering valve with soluble material is to fix the soluble sealing ring at the position of the annular end face formed by the inner side of the shell and the outer side of the upper connector, and then lower the gas gathering valve into the well. The outer surface of the soluble sealing ring interacts with the oil well fluid and dissolves after a preset dissolution time, and the exhaust channel is opened.

[0020] When the associated gas pressure inside the casing is greater than the pressure inside the gas collecting valve tubing and the deformation stress of the rubber valve core, the rubber valve core contracts towards the center, and the associated gas enters the tubing through the exhaust port; when the associated gas pressure inside the casing annulus decreases and is less than the pressure inside the tubing and the deformation stress of the rubber valve core, the rubber valve core recovers its expanded state under the action of its own extensional physical and chemical properties, and re-fits and seals against the inner wall of the casing.

[0021] The beneficial effects of this invention are:

[0022] (1) The oil well blowout prevention gas gathering valve of this invention uses soluble materials. The rubber valve core formed by vulcanizing rubber on the metal skeleton of the valve core has good ability to shrink and deform under external pressure, so as to open the valve core at a lower pressure. At the same time, it has strong resistance to internal pressure and achieves good unidirectional flow sealing. In addition, in view of the special situation of wellhead oil spill, pressurization and well kick during the production process, in accordance with the well control requirements, the soluble sealing ring is set to block the pressure transmission between the inside and outside of the gas gathering valve and temporarily and reliably close the gas gathering valve. When the oil well is in normal production, the outer surface of the soluble sealing ring interacts with the oil well fluid and dissolves after a preset dissolution time (3-5 days). The exhaust channel is opened, which meets the requirement that the gas gathering valve intake channel is closed during the pumping operation of the new well and that no additional operation is required after normal production. The gas gathering valve is automatically reopened, which reduces the operation risk of workers.

[0023] (2) The oil well blowout prevention gas gathering valve of the present invention uses soluble materials to change the existing mechanical pressure differential opening and closing to electrochemical soluble material erosion and unsealing. The sealing performance of the soluble sealing ring is more reliable than the mechanical closing sealing performance of the sliding sleeve. It does not require a second well opening operation, which reduces the workload of employees, shortens the technical operation process, improves work efficiency, and has a simpler structure and cost advantage. It solves the problem of difficult pressure relief and safety risks of the casing in some oil wells with continuous high pressure after production, as well as the overpressure operation risk of opening the sliding sleeve when the wellhead is pressured.

[0024] (3) The present invention uses a blowout prevention gas gathering valve made of soluble materials to change the associated gas recovery process from the surface to the wellbore. It can make full use of the favorable conditions of the high temperature environment in the wellbore, suppress freezing during the gas gathering process, extend the life of the gas gathering valve and improve the reliability of the gas gathering process. It effectively solves the problems of large installation workload, easy freezing and blockage in winter, short service life, small gas gathering volume, many sealing points and easy oil and gas leakage, and high safety and environmental risks of surface gas gathering valves. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the structure of the blowout prevention and gas collection valve for oil wells using soluble materials, as described in this invention.

[0026] In the diagram, 1. Upper connector, 2. Lower connector, 3. Housing, 4. Air inlet, 5. Exhaust passage, 6. Exhaust port, 7. Valve core metal skeleton, 8. Rubber valve core, 9. Soluble sealing ring, 10. First sealing ring, 11. Second sealing ring, 12. Third sealing ring. Detailed Implementation

[0027] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0028] This invention employs a blowout prevention gas collection valve made of soluble materials, shifting the associated gas recovery process from the surface to inside the wellbore. This fully utilizes the favorable conditions of the high-temperature environment within the wellbore and effectively solves the problem of valve body and pipeline freezing during associated gas recovery in winter. Specifically, as... Figure 1 As shown, the lower end of the upper connector 1 and the upper end of the lower connector 2 are connected by threads to form the main structure of the valve body. The upper end of the housing 3 is connected to the outer wall of the upper connector 1 by threads; the lower end of the housing 3 is connected to the outer shell of the valve core metal skeleton 7 by threads. The valve core metal skeleton 7 and the rubber valve core 8 are formed into an integral structure by vulcanization process, which becomes the valve core of the gas collecting valve.

[0029] The gas collecting valve of this invention has a compact overall structure, high integration, small size, few sealing points, reliable sealing process, and long service life. The valve core, composed of a metal skeleton and a rubber valve core, features large gas collecting capacity, low starting pressure, corrosion resistance, and scale prevention.

[0030] Compared to surface gas gathering valves, this system eliminates the need for surface gas gathering pipelines. It is installed during pump inspection, incurring no additional installation costs or labor requirements, and requires no routine maintenance. With fewer vulnerable parts, its lifespan is more than double that of existing surface gas gathering valves, and its gas gathering capacity is increased by 5-10 times, resulting in superior overall economic performance. Compared to sliding-sleeve downhole blowout preventer gas gathering valves, it reduces the need for secondary opening operations at the wellhead, making it particularly suitable for unattended well sites. It eliminates the risk of sliding-sleeve failure due to factors such as wax buildup and sand production within the wellbore, offering significant technological advantages and enhanced safety and environmental friendliness.

[0031] Example 1

[0032] This invention employs a blowout prevention and gas collection valve made of soluble materials, comprising an upper connector 1, the lower end of which is connected to a lower connector 2 to form the main structure of the valve body. The outer wall of the upper connector 1 is connected to a housing 3 by threads, and a first sealing ring 10 is provided at the connection between the housing 3 and the upper connector 1. A valve core metal frame 7 is connected to the inner wall of the housing 3 near the lower connector 2, and a rubber valve core 8 is connected to the valve core metal frame 7. The inner wall of the valve core metal frame 7 is connected to the outer wall of the lower connector 2, and a third sealing ring 12 is provided at the connection between the valve core metal frame 7 and the lower connector 2.

[0033] The upper connector 1 has several sets of exhaust ports 6 on its pipe wall, and the housing 3 has several sets of air inlets 4 at the connection between the housing 3 and the valve core metal skeleton 7. The upper connector 1, lower connector 2, valve core metal skeleton 7, rubber valve core 8, and housing 3 together form an exhaust channel 5 that connects the air inlets 4 and the exhaust ports 6. A soluble sealing ring 9 is provided in the exhaust channel 5 near the exhaust ports 6. The soluble sealing ring 9 is located at the annular end face formed by the inner side of the housing 3 and the outer side of the upper connector 1, and is used to block the connection between the air inlets 4 and the exhaust ports 6.

[0034] The soluble sealing ring 9, specifically designed for blowout prevention in the pump-running process, is made of soluble magnesium-aluminum alloy or soluble rubber material. It can withstand a pressure differential of 4 MPa, a temperature greater than 30°C, and a well fluid salinity of 3000-50000 mg / L, with a dissolution time of 3-5 days. This technology has been validated and widely applied in shale oil well fracturing operations (soluble bridge plugs). It is reliable, suitable for large-scale industrial production, and meets the requirements for gas gathering valve sealing, pressure, dissolution time, and well control during operations.

[0035] Example 2

[0036] This invention relates to an oil well blowout prevention gas gathering valve made of soluble materials. Its main components include an upper connector 1, a lower connector 2, a housing 3, a valve core metal skeleton 7, a rubber valve core 8, and a soluble sealing ring 9. The upper connector 1 is fixedly connected to the tubing hanger inside the wellbore via threads. The lower connector 2 is connected to the oil well production tubing string. The overall inner and outer diameters meet the size requirements of the wellbore and tubing string; that is, the internal diameter of the valve body formed by the connection of the upper connector 1 and the lower connector 2 is consistent with and communicates with the inner diameter of the tubing. The gas gathering valve's inlet channel communicates with the annulus circumference of the casing and the exhaust channel communicates with the tubing. It is installed on the tubing hanger near the wellhead within the annular space of the casing and tubing.

[0037] The main body of the gas collecting valve is composed of an upper connector 1 and a lower connector 2 connected together, with a second sealing ring 11 installed at the connection between the upper connector 1 and the lower connector 2. The valve core is formed by vulcanizing a metal core skeleton 7 and a rubber valve core 8 into a single structure. Specifically, the rubber valve core 8 is made of oil-resistant and heat-resistant nitrile rubber, which can meet the requirements of daily production, hot washing, corrosion prevention, scale prevention, and sealing of oil wells, and has a long service life. To enhance the adhesion of the rubber, the end where the metal core skeleton 7 connects to the rubber valve core 8 is provided with several sets of toothed structures.

[0038] Using the pressure difference between the casing annulus and the tubing as the driving force, when the associated gas pressure in the casing is higher than the back pressure in the tubing, the valve core opens, and the associated gas enters the tubing to form an oil-gas mixture with the oil flow; when the pressure difference decreases to a certain value, the valve core closes, the gas collection process ends, and the oil-gas leakage in the tubing into the casing annulus is prevented.

[0039] To avoid the risks associated with workers having to return to the well a second time, this example uses a soluble sealing ring 9 made of soluble material. During the commissioning of a new well, it is used in conjunction with a blowout preventer and well sealer. This technical measure seals the pressure transmission between the annulus and the tubing, allowing the tubing to remain open to the atmosphere at atmospheric pressure. If the gas gathering valve were to open at this time, oil and gas would leak into the tubing, posing a safety risk to wellhead operations and potentially causing a blowout, thus jeopardizing safe well operations. To address this, the soluble sealing ring 9 blocks the pressure transmission between the inside and outside of the gas gathering valve, temporarily closing it. When the well is in normal production, the outer surface of the soluble sealing ring 9 interacts with the well fluid, dissolving after a preset dissolution time (3-5 days), opening the venting channel. This fulfills the requirement of closing the gas gathering valve's inlet channel during pumping operations in a new well, and automatically reopens the gas gathering valve after normal production without requiring a second well return to normal operation.

[0040] Example 3

[0041] like Figure 1 As shown, this invention is vertically installed on the tubing hanger near the wellhead (the installation position can also be appropriately lowered according to well conditions). The upper connector 1 is threadedly connected to the tubing hanger inside the wellbore; the lower end of the upper connector 1 is threadedly connected to the upper end of the lower connector 2 to form the main structure; the upper end of the housing 3 is threadedly connected to the outer shell of the upper connector 1; the lower end of the housing 3 is threadedly connected to the outer shell of the valve core metal skeleton 7; the valve core metal skeleton 7 and the rubber valve core 8 are vulcanized to form an integral structure, becoming the valve core of the gas collecting valve; the valve core metal skeleton 7 is threadedly fixedly installed on the outer wall of the lower connector 2; the upper connector 1, lower connector 2, valve core metal skeleton 7, rubber valve core 8, and housing 3 together form the exhaust channel 5.

[0042] The upper connector 1 is provided with multiple sets of exhaust ports 6, which are connected to the oil pipe; the lower end of the housing 3 is provided with multiple sets of air inlets 4 above the connection between the lower end of the housing 3 and the metal skeleton of the valve core, which are connected to the exhaust channel 5; the rubber valve core 8 is shaped like an open "trumpet", and is tightly attached to the inner wall of the housing 3 in an "interference fit" manner to form an annular contraction sealing surface with the metal surface. The upper and lower spaces of the sealing surface are connected to the exhaust ports 6 and the air inlets 4 through the exhaust channel 5, respectively, forming a differential pressure single-flow control switch.

[0043] Unlike traditional metal ball valves where the air passage is located in the center hole of the valve seat, the air passage in this gas collecting valve is formed by the annular sealing surface of the rubber valve core 8 and the inner metal surface of the housing 3, significantly increasing the flow area. The lower connector 2 of the valve body is connected to the production tubing string of the oil well, and the overall inner and outer diameters meet the size requirements of the wellbore and tubing string. The upper connector 1 and the lower connector 2 are connected by threads and a second sealing ring 11. The valve core metal skeleton 7 is reliably fixed to the lower connector 2 by threads and a third sealing ring 12.

[0044] The air passage is the annular inner contact surface between the rubber valve core 8 and the housing 3, which features a large air passage capacity. The open "trumpet" rubber valve core 8, installed in an "interference fit" manner, fits against the inner wall of the housing 3 over a large area, forming an annular surface seal. It has a large unidirectional pressure resistance capacity against the oil pipe. When the pressure inside the oil pipe acts on the upper surface of the rubber valve core 8, the rubber valve core 8 is tightly attached to the metal inner wall surface of the housing 3. The higher the pressure, the tighter the seal between the rubber valve core 8 and the inner wall of the housing 3, exhibiting good pressure resistance and unidirectional flow performance.

[0045] Furthermore, the rubber valve core 8 has good ability to contract and deform under external pressure, enabling the valve core to open at a lower pressure. When the associated gas in the casing annulus exerts pressure on the lower surface of the rubber valve core 8, and the pressure of the associated gas in the casing is greater than the pressure in the oil pipe of the gas gathering valve and the deformation stress of the rubber valve core 8, the rubber valve core 8 contracts towards the center and separates from the inner surface of the shell 3, opening the gas gathering channel, and the associated gas enters the oil pipe through the exhaust port 6; when the pressure of the associated gas in the casing annulus decreases and is less than the pressure in the oil pipe and the deformation stress of the rubber valve core 8, the rubber valve core 8 recovers its expanded state under the action of its own extension physicochemical properties, re-sealing with the inner wall of the shell 3, and closing the exhaust channel 5; the associated gas in the well casing annulus enters the pressure recovery period, and the cycle of pressure buildup, opening and releasing, and re-pressure buildup of the associated gas in the casing annulus is repeated.

[0046] Furthermore, a soluble sealing ring 9 is installed inside the gas gathering valve. The soluble sealing ring 9 is made of soluble magnesium-aluminum alloy or soluble rubber material and is installed on the annular end face formed by the lower end face of the inner cavity of the housing 3 and the protruding step surface of the upper connector 1. It is used to seal the space connecting the exhaust channel 5 and the exhaust port 6. Before the pump is put into production, the gas gathering valve is in the closed state, which can block the pressure transmission inside and outside the gas gathering valve and prevent well fluid leakage through the gas gathering valve during the well process, thus preventing well control risks. After the gas gathering valve is put into the well and the oil well is in normal production, the outer surface of the soluble sealing ring 9 interacts with the well fluid and dissolves after a preset erosion time (3-5 days) until the seal fails. The exhaust channel 5 and the exhaust port 6 are then connected, realizing the gas gathering valve's blowout prevention capability during the new well production operation and its function of automatically opening according to a preset time.

[0047] Example 4

[0048] The method of using the soluble material oil well blowout prevention gas gathering valve of the present invention involves using the above-mentioned soluble material oil well blowout prevention gas gathering valve. Specifically, the soluble sealing ring 9 is fixed at the annular end face position formed by the inner side of the housing 3 and the outer side of the upper connector 1. Then, the gas gathering valve is lowered into the well. The outer surface of the soluble sealing ring 9 interacts with the oil well fluid and dissolves after a preset erosion time, and the exhaust channel 5 is opened.

[0049] During the process of pressure buildup in the casing annulus and the rise in associated gas pressure, the associated gas in the casing annulus exerts pressure on the sealing surface between the rubber valve core 8 and the housing 3. When the associated gas pressure inside the casing exceeds the pressure inside the tubing of the gas gathering valve and the deformation stress of the rubber valve core 8, the rubber valve core 8 contracts towards the center, opening the gas gathering channel, and the associated gas enters the tubing through the vent port 6. When the associated gas pressure in the casing annulus decreases and becomes less than the pressure inside the tubing and the deformation stress of the rubber valve core 8, the rubber valve core 8 recovers its expanded state under its own extensional physical and chemical properties, re-sealing against the inner wall of the housing 3, closing the gas gathering channel, and terminating the gas gathering process, preventing oil and gas leakage from the tubing into the casing annulus. The associated gas in the casing annulus then enters the pressure buildup and recovery period, repeatedly realizing the cyclical process of pressure buildup, opening and releasing, and re-pressure buildup of the associated gas in the casing annulus. The entire process is completed inside the wellbore, with no change to the surface process.

[0050] This invention is designed to recover associated gas separated from crude oil at the bottom of the well during normal oil well production, allowing it to re-enter the oil gathering process and be mixed and transported to downstream sites. The gas gathering valve meets the strength, pressure-bearing requirements, backflow prevention, blowout prevention, and the technical requirements of the oil wellbore for the minimum inner diameter, maximum outer diameter, and service life of tools. When the associated gas pressure in the annulus exceeds the back pressure in the tubing, creating a pressure differential, the gas gathering valve operates to maximize the recovery of associated gas. This invention effectively addresses the risks of leakage in surface gas gathering valves and pipeline connections, the potential for freezing in winter, the difficulties in disassembling and assembling gas gathering pipelines during well workover operations, and the well control requirements for new well commissioning.

Claims

1. An oil well blowout prevention and gas collection valve using soluble materials, characterized in that, The valve body includes an upper connector (1), the lower end of which is connected to a lower connector (2) to form the main structure of the valve body. The outer wall of the upper connector (1) is connected to a housing (3) by threads. The inner wall of the housing (3) is connected to a valve core metal frame (7) near the lower connector (2). A rubber valve core (8) is connected to the valve core metal frame (7). The inner wall of the valve core metal frame (7) is connected to the outer wall of the lower connector (2). The upper connector (1) has several sets of exhaust ports (6) on its pipe wall, and the housing (3) and the valve core metal skeleton (7) have several sets of air inlets (4) at their connection. The upper connector (1), lower connector (2), valve core metal skeleton (7), rubber valve core (8), and housing (3) together form an exhaust channel (5) that connects the air inlet (4) and the exhaust port (6). A soluble sealing ring (9) is provided near the exhaust port (6) in the exhaust channel (5). The soluble sealing ring (9) blocks the connection between the air inlet (4) and the exhaust port (6).

2. The oil well blowout prevention and gas collection valve using soluble materials according to claim 1, characterized in that, The soluble sealing ring (9) is located at the annular end face formed by the inner side of the housing (3) and the outer side of the upper connector (1).

3. The oil well blowout prevention and gas collection valve using soluble materials according to claim 2, characterized in that, The soluble sealing ring (9) is made of soluble magnesium-aluminum alloy or soluble rubber material.

4. The oil well blowout prevention and gas collection valve using soluble materials according to claim 1, characterized in that, The rubber valve core (8) is connected to the valve core metal skeleton (7) by a vulcanization process to form an integral structure.

5. The oil well blowout prevention and gas collection valve using soluble materials according to claim 4, characterized in that, The rubber valve core (8) is press-fitted to the inner wall of the housing (3) to form an annular shrink sealing surface. The upper and lower spaces of the sealing surface are respectively connected to the exhaust port (6) and the air inlet (4).

6. The oil well blowout prevention and gas collection valve using soluble materials according to claim 1, characterized in that, The valve core metal skeleton (7) is connected to the rubber valve core (8) at one end, which is provided with several sets of rack structures.

7. The oil well blowout prevention and gas collection valve using soluble materials according to claim 1, characterized in that, A first sealing ring (10) is provided at the connection between the housing (3) and the upper connector (1); A second sealing ring (11) is provided at the connection between the upper connector (1) and the lower connector (2); A third sealing ring (12) is provided at the connection between the valve core metal skeleton (7) and the lower connector (2).

8. The oil well blowout prevention and gas collection valve using soluble materials according to claim 1, characterized in that, The upper connector (1) is connected to the oil pipe hanger by a thread, and the lower connector (2) is connected to the oil pipe string by a thread. The internal diameter of the valve body formed by the connection of the upper connector (1) and the lower connector (2) is consistent with and connected to the inner diameter of the oil pipe.

9. The method of using the blowout prevention gas collection valve of the oil well using soluble material, as described in any one of claims 1 to 8, specifically, the soluble sealing ring (9) is fixed at the annular end face position formed by the inner side of the shell (3) and the outer side of the upper connector (1), and then the gas collection valve is lowered into the well. The outer surface of the soluble sealing ring (9) interacts with the oil well fluid and dissolves after a preset erosion time, and the exhaust channel (5) is opened. When the gas pressure of the associated gas in the casing is greater than the pressure in the oil pipe of the gas gathering valve and the deformation stress of the rubber valve core (8), the rubber valve core (8) contracts towards the center, and the associated gas enters the oil pipe through the exhaust port (6); when the gas pressure of the associated gas in the casing annulus decreases and is less than the pressure in the oil pipe and the deformation stress of the rubber valve core (8), the rubber valve core (8) recovers its expansion state under the action of its own extension physical and chemical properties and re-fits and seals with the inner wall of the shell (3).

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