A mechanically pressurized wellhead device for producing heavy oil based on electric heating

Abstract

and a tube connecting the discharging opening of the pump with a check valve in it at the pump end, and a check valve in it at the pump end. The pump is closed by a check valve in the oil drain plug, and the pump is closed by a check valve in the oil drain plug, and the pump is closed by a check valve in the oil drain plug, and the pump is closed by a check valve in the oil drain plug.

Description

Technical Field

[0001] The invention relates to the technical field of petroleum extraction, in particular to a mechanically pressurized extraction wellhead device based on electrically heated heavy oil. Background Art

[0002] The electric heating heavy oil extraction process enters the hollow rod through the cable, and uses the skin effect principle to convert electrical energy into thermal energy to heat the heavy oil in the wellbore. During the heating process, it is necessary to ensure that the heat can be effectively transferred to the crude oil to reduce its viscosity and increase its fluidity. Mechanical equipment such as oil pumps are used to suck the liquid in the wellbore, thereby increasing the negative pressure in the wellbore and making the heavy oil easier to extract; however, due to the uneven distribution of the viscosity of the heavy oil downhole, the electric heating system is difficult to ensure the uniformity of the viscosity of the heavy oil. Therefore, it is difficult to extract heavy oil with higher viscosity through the oil pump. The heavy oil with higher viscosity increases the obstruction of the oil pump, increases energy consumption, and easily causes the sucker rod and the pumping unit to move out of sync, which can easily lead to damage to the pumping unit and the oil pump over time and reduce the oil extraction efficiency.

[0003] When this happens, the electric heating temperature can be increased, but the higher the temperature, the more likely it is to cause failure of other components and it is difficult to control. Some wellhead devices will inject nitrogen into the casing to push the crude oil to the wellhead and improve the oil pumping efficiency. However, the heavy oil above the oil pipe will still exert a large pressure on the oil pump, causing wear of the oil pump, and the output pressure of the booster pump needs to be precisely controlled to ensure that the nitrogen can be injected into the formation at an appropriate pressure. If the pressure is not properly controlled, it may lead to excessive or insufficient nitrogen injection, thereby affecting the oil pumping efficiency.

[0004] As the amount of nitrogen increases, the casing pressure in the casing will also increase. If equipment such as oil pumps operate in an environment with excessively high casing pressure for a long time, it is easy to cause additional wear and corrosion of components and reduce oil pumping efficiency. At the same time, it is difficult to improve oil pumping efficiency if the amount of nitrogen is too small. Casing pressure refers to the process of oil and gas production. When the bottom hole fluid (including crude oil, natural gas, etc.) rises in the wellbore, it will generate a certain pressure due to gravity and other factors. When these fluids rise to the annular space between the oil pipe and the casing, some gas will accumulate here, forming casing pressure; therefore, it is very important to maintain a moderate and stable casing pressure during the oil pumping process.

[0005] Therefore, the present invention provides a mechanically pressurized production wellhead device based on electrically heated heavy oil. Summary of the Invention

[0006] The present invention provides a mechanically pressurized wellhead device for producing electrically heated heavy oil, which solves the problems of low oil extraction efficiency in the background technology by arranging a compressor, a pneumatic diaphragm pump and the like.

[0007] The technical solutions of the present invention are as follows:

[0008] A mechanically supercharged wellhead device for producing electrically heated heavy oil, comprising: a mounting seat, a Christmas tree, a tubing head, and a casing head mounted on the top of the mounting seat from top to bottom, an oil pipe mounted in the tubing head, a casing mounted in the casing head, a pneumatic diaphragm pump mounted on the top of the mounting seat, an air intake pipe 1 mounted between the air intake end of the pneumatic diaphragm pump and the tubing head, and an oil pumping pipe mounted between the liquid intake end of the pneumatic diaphragm pump and the oil pipe;

[0009] A compressor and a gas storage bottle are installed on the top of the mounting seat, an air intake pipe 2 is installed between the compressor output end and the oil pipe head, a regulating valve 1 is installed on the compressor input end, a mixing chamber is installed on the regulating valve 1, and a connecting pipe 1 is installed between the mixing chamber and the gas storage bottle;

[0010] An air intake pipe 3 is installed between the air intake pipe 1 and the mixing chamber, a regulating valve 2 is installed on the air intake pipe 3, and a connecting pipe 2 is installed between the regulating valve 2 and the regulating valve 1.

[0011] Preferably, one end of the air inlet pipe is fixedly connected and communicated with one end of the oil pipe head, and the other end is fixedly connected to the pneumatic diaphragm pump. One end of the oil extraction pipe is fixedly connected and communicated with the pneumatic diaphragm pump, and the other end passes through the oil tree and is fixedly connected to the oil pipe.

[0012] Preferably, the air intake pipe 2 is fixedly connected and communicated with the other end of the oil pipe head, the two ends of the connecting pipe 1 are respectively communicated with the mixing chamber and the gas storage bottle, and one end of the air intake pipe 3 is fixedly connected and communicated with the air intake pipe 1, and the other end is fixedly connected and communicated with the mixing chamber.

[0013] Preferably, an air tank is installed on the top of the mounting seat, and an air outlet pipe and an oil drain pipe are also installed on the pneumatic diaphragm pump. One end of the air outlet pipe is fixedly connected to the pneumatic diaphragm pump, and the other end is fixedly connected to and communicated with the air tank. A connecting pipe three is installed between the air tank and the mixing chamber, and the two ends of the connecting pipe three are respectively fixedly connected to and communicated with the air tank and the mixing chamber.

[0014] Preferably, the gas storage cylinder is filled with nitrogen.

[0015] Preferably, the first intake pipe is equipped with an electrically controlled valve and a first pressure monitor, the second intake pipe is equipped with a second electrically controlled valve and a second pressure monitor, and the third oil drain pipe is equipped with a third electrically controlled valve and a third pressure monitor.

[0016] Preferably, a switch valve is installed on the gas cylinder, and the switch valve is used to open and close the gas cylinder and the connecting pipe.

[0017] Preferably, the regulating valve includes a fixed cylinder, one end of which is fixedly connected to and communicated with the compressor input end, and the other end is fixedly connected to and communicated with the connecting pipe 2. The fixed cylinder is provided with a valve cavity at the end close to the compressor, a fixed ring is fixedly connected inside the fixed cylinder, a sliding rod is slidably connected inside the fixed ring, and the sliding rod passes through the fixed ring, one end of the sliding rod close to the valve cavity is fixedly connected to a valve core, and the other end is fixedly connected to a piston, and the piston is tightly fitted with the fixed cylinder, and a spring is installed between the fixed ring and the piston.

[0018] Preferably, the regulating valve second includes a valve body, the valve body is provided with a valve cavity second and a valve cavity third, the valve cavity second and the valve cavity third are communicated with the intake pipe third, a valve core second is provided between the valve cavity second and the valve cavity third, the valve core second is located in the gap between the valve cavity second and the valve cavity third and matches the gap between the valve cavity second and the valve cavity third, a fixed cylinder second is provided on the top of the valve body, one end of the fixed cylinder second is fixedly connected to the valve body, and the other end is fixedly connected to and communicated with the connecting pipe second, and the top of the valve body is slidably connected with a sliding rod second, one end of the sliding rod second extends into the fixed cylinder second, and the other end passes through the valve core second and is fixedly connected to the valve core second, the end of the sliding rod second close to the fixed cylinder second is fixedly connected to a piston second, and the piston second is tightly fitted with the fixed cylinder second, the end of the sliding rod second away from the fixed cylinder second is fixedly connected to a baffle, and a spring second is installed between the baffle and the bottom of the valve body.

[0019] Preferably, the pneumatic diaphragm pump includes two working chambers, a diaphragm is provided in the working chamber, an air distribution valve is provided between the two working chambers, a connecting rod is provided in the air distribution valve, and the two ends of the connecting rod are respectively connected to the two diaphragms. The pneumatic diaphragm pump is provided with two one-way ball valves on the side of the two diaphragms away from the air distribution valve, the one-way ball valve is communicated with the working chamber, the air distribution valve is communicated with the air inlet pipe and the part of the working chamber located between the two diaphragms, and the air outlet pipe is communicated with the part of the working chamber located between the two diaphragms.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] 1. The present invention increases the casing pressure by high-pressure nitrogen to press the heavy oil upward, while the pneumatic diaphragm pump further extracts crude oil from the oil pipe outlet, which not only increases the pressure below the oil pipe but also reduces the pressure above the oil pipe, avoiding damage to the oil pump caused by increased casing pressure and improving oil recovery efficiency.

[0022] 2. The present invention allows the natural gas in the casing to enter the pneumatic diaphragm pump, which can not only increase the oil pumping efficiency above the oil pipe through the pneumatic diaphragm pump, but also reduce the excessively high casing pressure downhole, thereby ensuring the oil pumping efficiency and avoiding damage to the well production equipment due to excessive casing pressure.

[0023] 3. The present invention adjusts the amount of gas injected into the well through regulating valve 1 and regulating valve 2 to prevent excessive or insufficient gas from affecting the oil pumping efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 is a perspective view of the wellhead assembly of the present invention;

[0025] Figure 2 This invention Figure 1 A partial enlarged view of middle A;

[0026] Figure 3 It is a three-dimensional diagram of the wellhead assembly of the present invention from another perspective;

[0027] Figure 4 This invention Figure 3 A partial enlarged view of middle B;

[0028] Figure 5 It is a cross-sectional schematic diagram of the Christmas tree, tubing head and casing head of the present invention;

[0029] Figure 6 is a schematic cross-sectional view of the pneumatic diaphragm pump of the present invention;

[0030] Figure 7 It is a cross-sectional schematic diagram of the regulating valve 2 of the present invention;

[0031] Figure 8 It is a cross-sectional schematic diagram of a regulating valve 1 of the present invention.

[0032] In the picture:

[0033] 1. Mounting base; 11. Christmas tree; 12. Tubing head; 13. Casing head; 14. Oil pipe; 15. Casing; 16. Gas storage tank; 17. Connecting pipe 3; 2. Pneumatic diaphragm pump; 21. Inlet pipe 1; 22. Outlet pipe; 23. Pumping pipe; 24. Oil discharge pipe; 25. Electric control valve 1; 26. Pressure monitor 1; 27. Electric control valve 3; 28. Pressure monitor 3; 29. ​​Working chamber; 210. Diaphragm; 211. Distribution valve; 212. Connecting rod; 213. One-way ball valve; 3. Compressor; 31. Inlet pipe 2; 32. Mixing chamber; 33. Connecting pipe one; 34. Inlet pipe three; 35. Electric control valve two; 36. Pressure monitor two; 4. Gas cylinder; 41. On-off valve; 5. Control valve one; 51. Fixed cylinder one; 52. Valve chamber one; 53. Fixed ring; 54. Slide rod; 55. Valve core one; 56. Piston one; 57. Spring one; 6. Control valve two; 61. Valve body; 62. Valve chamber two; 63. Valve chamber three; 64. Valve core two; 65. Fixed cylinder two; 66. Slide rod two; 67. Piston two; 68. Baffle; 69. Spring two; 7. Connecting pipe two. DETAILED DESCRIPTION

[0034] The following embodiments of the present invention are described in further detail with reference to the accompanying drawings and examples. The following examples are used to illustrate the present invention but are not intended to limit the scope of the present invention.

[0035] Example 1

[0036] like Figure 1-Figure 5 As shown, the present invention provides a mechanically pressurized wellhead device for producing heavy oil based on electric heating, comprising: a mounting base 1, on the top of which are mounted, from top to bottom, a Christmas tree 11, a tubing head 12, and a casing head 13; a tubing 14 is mounted in the tubing head 12; a casing 15 is mounted in the casing head 13; a pneumatic diaphragm pump 2 is also mounted on the top of the mounting base 1; an air intake pipe 21 is mounted between the air intake end of the pneumatic diaphragm pump 2 and the tubing head 12; and a pumping pipe 23 is mounted between the liquid intake end of the pneumatic diaphragm pump 2 and the tubing 14;

[0037] A compressor 3 and a gas cylinder 4 are mounted on the top of the mounting base 1. An air inlet pipe 2 31 is mounted between the output end of the compressor 3 and the tubing head 12. A regulating valve 1 5 is mounted on the input end of the compressor 3. A mixing chamber 32 is mounted on the regulating valve 1 5. A connecting pipe 1 33 is mounted between the mixing chamber 32 and the gas cylinder 4.

[0038] An intake pipe 3 34 is installed between the intake pipe 1 21 and the mixing chamber 32 , a regulating valve 2 6 is installed on the intake pipe 3 34 , and a connecting pipe 2 7 is installed between the regulating valve 2 6 and the regulating valve 1 5 .

[0039] The gas cylinder 4 is filled with nitrogen.

[0040] An electrically controlled valve 1 25 and a pressure monitor 1 26 are installed on the intake pipe 1 21, an electrically controlled valve 2 35 and a pressure monitor 2 36 are installed on the intake pipe 2 31, and an electrically controlled valve 3 27 and a pressure monitor 3 28 are installed on the oil drain pipe 24; the electrically controlled valve 1 25 is used to control the opening and closing of the intake pipe 1 21, and the pressure monitor 1 26 is used to monitor the pressure in the intake pipe 1 21; the electrically controlled valve 2 35 is used to control the opening and closing of the intake pipe 2 31, and the pressure monitor 2 36 is used to monitor the pressure in the intake pipe 2 31; the electrically controlled valve 3 27 is used to control the opening and closing of the oil drain pipe 24, and the pressure monitor 3 28 is used to monitor the pressure in the oil drain pipe 24.

[0041] The gas cylinder 4 is provided with a switch valve 41 , which is used to open and close the gas cylinder 4 and the connecting pipe 33 .

[0042] The pneumatic diaphragm pump 2 includes two working chambers 29, a diaphragm 210 is provided in the working chamber 29, an air distribution valve 211 is provided between the two working chambers 29, a connecting rod 212 is provided in the air distribution valve 211, and the two ends of the connecting rod 212 are respectively connected to the two diaphragms 210. The pneumatic diaphragm pump 2 is provided with two one-way ball valves 213 on the side of the two diaphragms 210 away from the air distribution valve 211. The one-way ball valve 213 is communicated with the working chamber 29, the air distribution valve 211 is communicated with the air inlet pipe 21 and the part of the working chamber 29 located between the two diaphragms 210, and the air outlet pipe 22 is communicated with the part of the working chamber 29 located between the two diaphragms 210.

[0043] like Figures 1-6 As shown, during heavy oil extraction, crude oil is extracted from the well through the oil pump in the oil pipe 14; the crude oil is discharged from the side channel of the Christmas tree 11 away from the oil pipe 23, and the pressure is monitored by the pressure monitoring valve on this side. When the heavy oil extraction efficiency decreases, the pressure changes, and the electric control valve 1 25, the electric control valve 2 35 and the switch valve 41 of the gas cylinder 4 are opened, and the compressor 3 is started. The nitrogen in the gas cylinder 4 enters the mixing chamber 32 from the connecting pipe 1 33 and then enters the compressor 3. The nitrogen is pressurized by the compressor 3, so that the pressurized nitrogen enters the oil pipe head 12 from the air inlet pipe 2 31. A part of the pressurized nitrogen enters the annular space between the oil pipe 14 and the casing 15, pushing the crude oil from the well to the oil pipe 14, thereby improving the oil extraction efficiency. The other part enters the pneumatic diaphragm pump 2 from the air inlet pipe 1 21, which is a pneumatic The diaphragm pump 2 provides power; high-pressure nitrogen first enters the air distribution valve 211 in the pneumatic diaphragm pump 2 from the air inlet pipe 21, and then sends the nitrogen into the working chamber 29 in turn, pushing the diaphragm 210 in the working chamber 29 to expand to one side, and drives the two diaphragms 210 to move synchronously through the connecting rod 212 on the two diaphragms 210; at the same time, the nitrogen is discharged from one working chamber 29 to the air outlet pipe 22, and the air distribution valve 211 automatically introduces the nitrogen into the other working chamber 29, pushing the diaphragms 210 to move in the opposite direction, thus forming a synchronous reciprocating motion of the two diaphragms 210. The reciprocating motion of the diaphragms 210 causes the volume of the working chamber 29 to change, forcing the two one-way ball valves 213 to open and close alternately, thereby continuously sucking in crude oil from the pumping pipe 23 and continuously discharging it from the oil discharge pipe 24, thereby improving the oil extraction efficiency.

[0044] By injecting high-pressure nitrogen into the annular space between the casing 15 and the oil pipe 14, the casing pressure in the well is increased, and the pressure of the crude oil flowing from the well to the oil pipe 14 is increased, thereby improving the efficiency of oil extraction; at the same time, the injected nitrogen is used to drive the pneumatic diaphragm pump 2 to work, and the crude oil is extracted from the oil pipe 14 and the oil pumping pipe 23, thereby improving the oil extraction efficiency; the oil pump principle is that the sucker rod pulls the plunger up and down reciprocatingly, so that the pump chamber pressure under the plunger is reciprocatingly increased and reduced. When the pump chamber pressure decreases, the crude oil in the well is pressed into the oil pipe 14 by the casing pressure, and when the pump chamber pressure increases, the crude oil is pressed upward into the oil pipe 14; therefore, in the process of the oil pump extracting crude oil, while the casing pressure increased by the high-pressure nitrogen presses the heavy oil upward, the pneumatic diaphragm pump 2 further extracts crude oil from the outlet of the oil pipe 14, which not only increases the pressure below the oil pipe 14, but also reduces the pressure above the oil pipe 14, avoids damage to the oil pump caused by the increased casing pressure, and improves oil extraction efficiency.

[0045] Example 2:

[0046] like Figure 1-Figure 4 As shown, an air tank 16 is installed on the top of the mounting base 1, and an air outlet pipe 22 and an oil drain pipe 24 are also installed on the pneumatic diaphragm pump 2. One end of the air outlet pipe 22 is fixedly connected to the pneumatic diaphragm pump 2, and the other end is fixedly connected to and communicated with the air tank 16. A connecting pipe three 17 is installed between the air tank 16 and the mixing chamber 32, and the two ends of the connecting pipe three 17 are respectively fixedly connected to and communicated with the air tank 16 and the mixing chamber 32.

[0047] When the viscosity of the heavy oil is suitable, if the downhole pressure monitoring system detects that the casing pressure is too high, the electrically controlled valve 1 25 is opened to allow the natural gas in the casing 15 to enter the pneumatic diaphragm pump 2. This can not only increase the oil pumping efficiency above the oil pipe 14 through the pneumatic diaphragm pump 2, but also reduce the excessively high casing pressure downhole, thereby ensuring the oil pumping efficiency and preventing the high casing pressure from damaging the well production equipment.

[0048] The natural gas enters the gas storage tank 16 through the gas outlet pipe 22 for collection, thus avoiding energy waste or environmental pollution.

[0049] The pneumatic diaphragm pump 2 is made of engineering plastics and has the characteristics of light weight, strong anti-aging ability, explosion-proof, etc. Due to its fully enclosed structure design, it is impossible to generate sparks after grounding, so it can still ensure safety when the driving gas is natural gas; the explosion-proof pneumatic diaphragm pump 2 will not overheat, and the pressurized gas is used as the power. The exhaust is an expansion and heat absorption process. The temperature of the pneumatic pump is reduced when it is working, and no harmful gas is discharged; it can pass liquids containing particles. Because it works in a volumetric manner and the inlet is a ball valve, it is not easy to be blocked, and is suitable for crude oil with high viscosity.

[0050] Example 3

[0051] like Figure 4 、 Figure 7-Figure 8As shown, the regulating valve 5 includes a fixed cylinder 51, one end of the fixed cylinder 51 is fixedly connected to and communicated with the input end of the compressor 3, and the other end is fixedly connected to and communicated with the connecting pipe 2 7. A valve cavity 52 is provided at the end of the fixed cylinder 51 close to the compressor 3, a fixed ring 53 is fixedly connected in the fixed cylinder 51, a sliding rod 54 is slidably connected in the fixed ring 53, and the sliding rod 54 passes through the fixed ring 53, one end of the sliding rod 54 close to the valve cavity 52 is fixedly connected to a valve core 55, and the other end is fixedly connected to a piston 56, and the piston 56 is tightly fitted with the fixed cylinder 51, and a spring 57 is installed between the fixed ring 53 and the piston 56.

[0052] The regulating valve 2 6 includes a valve body 61, which is provided with a valve cavity 2 62 and a valve cavity 3 63. The valve cavity 2 62 and the valve cavity 3 63 are communicated with the intake pipe 3 34. A valve core 2 64 is provided between the valve cavity 2 62 and the valve cavity 3 63. The valve core 2 64 is located in the gap between the valve cavity 2 62 and the valve cavity 3 63 and matches the gap between the valve cavity 2 62 and the valve cavity 3 63. A fixed cylinder 2 65 is provided on the top of the valve body 61. One end of the fixed cylinder 2 65 is fixedly connected to the valve body 61, and the other end is connected to the connecting pipe Two 7 are fixedly connected and communicated with each other, and a slide rod 2 66 is slidably connected to the top of the valve body 61, one end of the slide rod 2 66 extends into the fixed cylinder 2 65, and the other end passes through the valve core 2 64 and is fixedly connected to the valve core 2 64, and the end of the slide rod 2 66 close to the fixed cylinder 2 65 is fixedly connected to the piston 2 67, and the piston 2 67 is tightly fitted with the fixed cylinder 2 65, and the end of the slide rod 2 66 away from the fixed cylinder 2 65 is fixedly connected to the baffle 68, and a spring 2 69 is installed between the baffle 68 and the bottom of the valve body 61.

[0053] like Figures 1-8As shown, by injecting nitrogen into the well while discharging nitrogen from the other end of the tubing head 12, it is avoided that excessive nitrogen injection affects the oil pumping efficiency; and, a part of the nitrogen enters the pneumatic diaphragm pump 2 from the intake pipe 1 21 to provide power for the pneumatic diaphragm pump 2, and the other part enters the mixing chamber 32 through the intake pipe 3 34 and enters the compressor 3; when the nitrogen passes through the regulating valve 2 6, the high-pressure nitrogen pushes the valve core 2 64 to move upward, opens the passage between the valve core 2 64 and the valve cavity 2 62 and the valve cavity 3 63, and allows the high-pressure nitrogen to pass through the intake pipe 3 34 and enter the compressor 3 through the regulating valve 1 5; when the nitrogen passes through the regulating valve 1 5, it presses the valve core 1 55 downward, opens the passage between the valve core 1 55 and the valve cavity 1 52, and allows the nitrogen to enter the compressor 3; when the amount of nitrogen injected is too much, the intake pipe 3 34 The greater the pressure, the further the valve core 2 64 is pushed downward, increasing the gap between the valve core 2 64 and the valve cavity 2 62 and the valve cavity 3 63, allowing more nitrogen to pass through, thereby reducing the amount of nitrogen in the casing 15. At the same time, the valve core 2 64 moves downward, pushing the piston 2 67 downward, and then the gas between the piston 2 67 and the piston 1 56 through the intake pipe 3 34 drives the piston 1 56 upward, reducing the gap between the valve core 1 55 and the valve cavity 1 52, and reducing the amount of gas passing through the regulating valve 1 5; the nitrogen in the gas cylinder 4, the low-pressure nitrogen discharged from the pneumatic diaphragm pump 2, and the high-pressure nitrogen entering from the intake pipe 3 34 all enter the compressor 3 from the mixing chamber 32. When the channel capacity of the regulating valve 1 5 is reduced, the amount of mixed gas entering the compressor 3 is reduced, thereby further reducing the amount of gas entering the well.

[0054] When the amount of nitrogen injected is too little, the pressure in the intake pipe three 34 becomes smaller, and the valve core two 64 moves upward under the thrust of the spring two 69, reducing the gap between the valve core two 64 and the valve cavity two 62 and valve cavity three 63, allowing less nitrogen to pass through, thereby increasing the amount of nitrogen in the casing 15. At the same time, the valve core two 64 moves upward, pushing the piston two 67 upward, and then the gas between the piston two 67 and the piston one 56 through the intake pipe three 34 drives the piston one 56 to move downward, increasing the gap between the valve core one 55 and the valve cavity one 52, increasing the amount of gas passing through the regulating valve one 5, and thus increasing the amount of gas entering the well.

[0055] It should be noted that when the upward thrust of piston 1 56 exerted by spring 1 57 is balanced by the downward thrust of piston 1 56 exerted by the gas in mixing chamber 32 and the pressure on the other side of piston 1 56, valve core 1 55 remains stable, thereby ensuring stable regulation of regulating valve 1 5; when the downward thrust of piston 1 56 exerted by the gas in intake pipe 3 34, the pressure on the other side of piston 2 67 and the upward thrust of piston 2 67 exerted by spring 2 69 are balanced, valve core 2 64 remains stable, thereby ensuring stable regulation of regulating valve 2 6.

[0056] The nitrogen in the gas cylinder 4, the low-pressure nitrogen discharged from the pneumatic diaphragm pump 2, and the high-pressure nitrogen entering from the intake pipe 3 34 are all re-injected into the well through the compressor 3, avoiding gas leakage and environmental pollution, while also improving resource utilization.

[0057] The embodiments of the present invention are provided for the purpose of illustration and description. Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations of the present invention. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A mechanically pressurized wellhead device for producing heavy oil based on electrical heating, comprising: A mounting seat (1), wherein a Christmas tree (11), a tubing head (12) and a casing head (13) are mounted on the top of the mounting seat (1) from top to bottom, an oil pipe (14) is mounted in the tubing head (12), and a casing (15) is mounted in the casing head (13), characterized in that: an air-operated diaphragm pump (2) is also mounted on the top of the mounting seat (1), an air-operated diaphragm pump (2) is mounted between the air-operated diaphragm pump (2) and the tubing head (12), and an oil extraction pipe (23) is mounted between the liquid-operated diaphragm pump (2) and the oil pipe (14); A compressor (3) and a gas storage bottle (4) are mounted on the top of the mounting seat (1); an air intake pipe (2) (31) is mounted between the output end of the compressor (3) and the oil pipe head (12); a regulating valve (1) (5) is mounted on the input end of the compressor (3); a mixing chamber (32) is mounted on the regulating valve (5); and a connecting pipe (1) (33) is mounted between the mixing chamber (32) and the gas storage bottle (4); An intake pipe 3 (34) is installed between the intake pipe 1 (21) and the mixing chamber (32), a regulating valve 2 (6) is installed on the intake pipe 3 (34), and a connecting pipe 2 (7) is installed between the regulating valve 2 (6) and the regulating valve 1 (5); The regulating valve (5) includes a fixed cylinder (51), one end of which is fixedly connected to and communicated with the input end of the compressor (3), and the other end is fixedly connected to and communicated with the connecting pipe (7). The fixed cylinder (51) is provided with a valve cavity (52) at one end close to the compressor (3). A fixed ring (53) is fixedly connected inside the fixed cylinder (51), and a sliding rod (54) is slidably connected inside the fixed ring (53), and the sliding rod (54) passes through the fixed ring (53). The sliding rod (54) is fixedly connected to a valve core (55) at one end close to the valve cavity (52), and is fixedly connected to a piston (56) at the other end, and the piston (56) is tightly fitted with the fixed cylinder (51), and a spring (57) is installed between the fixed ring (53) and the piston (56). The regulating valve 2 (6) includes a valve body (61), the valve body (61) is provided with a valve cavity 2 (62) and a valve cavity 3 (63), the valve cavity 2 (62) and the valve cavity 3 (63) are communicated with the intake pipe 3 (34), a valve core 2 (64) is provided between the valve cavity 2 (62) and the valve cavity 3 (63), the valve core 2 (64) is located in the gap between the valve cavity 2 (62) and the valve cavity 3 (63) and matches the gap between the valve cavity 2 (62) and the valve cavity 3 (63), a fixed cylinder 2 (65) is provided on the top of the valve body (61), one end of the fixed cylinder 2 (65) is fixedly connected to the valve body (61), and the other end is fixed to the The connecting pipe 2 (7) is fixedly connected and communicated with each other. The top of the valve body (61) is slidably connected with a slide rod 2 (66). One end of the slide rod 2 (66) extends into the fixed cylinder 2 (65), and the other end passes through the valve core 2 (64) and is fixedly connected to the valve core 2 (64). The end of the slide rod 2 (66) close to the fixed cylinder 2 (65) is fixedly connected to the piston 2 (67), and the piston 2 (67) is tightly fitted with the fixed cylinder 2 (65). The end of the slide rod 2 (66) away from the fixed cylinder 2 (65) is fixedly connected to the baffle (68), and a spring 2 (69) is installed between the baffle (68) and the bottom of the valve body (61).

2. The mechanically pressurized wellhead device for producing heavy oil based on electrical heating according to claim 1, characterized in that: One end of the air inlet pipe (21) is fixedly connected to and communicates with one end of the oil pipe head (12), and the other end is fixedly connected to the pneumatic diaphragm pump (2). One end of the oil extraction pipe (23) is fixedly connected to and communicates with the pneumatic diaphragm pump (2), and the other end passes through the oil tree (11) and is fixedly connected to the oil pipe (14).

3. The mechanically pressurized wellhead device for producing heavy oil based on electrical heating according to claim 1, characterized in that: The second intake pipe (31) is fixedly connected to and communicates with the other end of the oil pipe head (12), and the two ends of the connecting pipe (33) are respectively communicated with the mixing chamber (32) and the gas storage bottle (4). One end of the third intake pipe (34) is fixedly connected to and communicates with the first intake pipe (21), and the other end is fixedly connected to and communicates with the mixing chamber (32).

4. The mechanically pressurized wellhead device for producing heavy oil based on electrical heating according to claim 1, characterized in that: An air storage tank (16) is installed on the top of the mounting base (1), and an air outlet pipe (22) and an oil discharge pipe (24) are also installed on the pneumatic diaphragm pump (2). One end of the air outlet pipe (22) is fixedly connected to the pneumatic diaphragm pump (2), and the other end is fixedly connected to and communicates with the air storage tank (16). A connecting pipe three (17) is installed between the air storage tank (16) and the mixing chamber (32), and the two ends of the connecting pipe three (17) are respectively fixedly connected to and communicate with the air storage tank (16) and the mixing chamber (32).

5. The mechanically pressurized wellhead device for producing heavy oil based on electrical heating according to claim 1, characterized in that: The gas storage cylinder (4) is filled with nitrogen.

6. The mechanically supercharged wellhead device for producing heavy oil based on electrical heating according to claim 4, characterized in that: The first intake pipe (21) is equipped with an electric control valve (25) and a first pressure monitor (26), the second intake pipe (31) is equipped with an electric control valve (35) and a second pressure monitor (36), and the third oil discharge pipe (24) is equipped with an electric control valve (27) and a third pressure monitor (28).

7. The mechanically pressurized wellhead device for producing heavy oil based on electrical heating according to claim 1, characterized in that: The gas cylinder (4) is provided with a switch valve (41), and the switch valve (41) is used for opening and closing between the gas cylinder (4) and the connecting pipe 1 (33).

8. The mechanically pressurized wellhead device for producing heavy oil based on electrical heating according to claim 4, characterized in that: The pneumatic diaphragm pump (2) includes two working chambers (29), each of which is provided with a diaphragm (210), and an air distribution valve (211) is provided between the two working chambers (29). A connecting rod (212) is provided in the air distribution valve (211), and both ends of the connecting rod (212) are connected to the two diaphragms (210). The pneumatic diaphragm pump (2) is provided with two one-way ball valves (213) on the side of the two diaphragms (210) away from the air distribution valve (211), and the one-way ball valves (213) are in communication with the working chamber (29). The air distribution valve (211) is in communication with an air inlet pipe (21) and a portion of the working chamber (29) located between the two diaphragms (210), and the air outlet pipe (22) is in communication with a portion of the working chamber (29) located between the two diaphragms (210).

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