Pumping unit and fluid balancing method

Abstract

The invention provides a pumping unit and a fluid balancing method, and belongs to the field of petroleum extraction machinery. The pumping unit comprises a base, a supporting seat is fixedly installed on the base, and a motor, a speed reducer and a support are installed on the supporting seat. The walking beam is connected with the bracket through a bearing seat; an output shaft of the speed reducer is connected with the walking beam through a crank and a connecting rod of the four-rod mechanism; the two ends of the walking beam are connected with a first horse head and a second horse head respectively, the first horse head and the second horse head are communicated through a connecting pipe arranged between the first horse head and the second horse head, an electric valve is arranged on the connecting pipe, and an electric cabinet is further arranged on the supporting seat and electrically connected with the electric valve. The oil pumping unit is used for two oil wells close to each other, the function that one oil pumping unit pumps two oil wells is achieved, the equipment investment of one oil pumping unit can be saved, the running loss of one oil pumping unit is reduced, and fluid balance is used for balancing the load difference of the two oil wells; after the balance box is arranged on the second horse head, the second horse head can be only used for pumping oil of one oil well, and fluid balance is used for weight difference between the oil well and the balance box.

Description

Technical Field

[0001] This invention relates to the field of oil extraction machinery, and in particular to an oil pumping unit and a fluid balancing method. Background Technology

[0002] The most commonly used oil well production system in oilfields is the rod pump production system, whose surface production equipment is mainly the pumping unit. Traditional oil production systems typically have one pumping unit per well, requiring a balancing mechanism to reduce power demands. With the increasing emphasis on comprehensive efficiency in oilfield development, the method of using one pumping unit to simultaneously produce oil from two wells has demonstrated better economic viability. Some oilfields in China have already conducted research and testing on this one-to-two pumping unit, designing various types of one-to-two oil production machinery. The main principles are a hydraulic cylinder-driven beam pumping unit structure, a hydraulic cylinder-driven pulley structure, and a crank-driven sheave structure. Hydraulic cylinder-driven walking beam pumping units can be balanced by setting a counterweight at the tail end of the walking beam. While balancing is easy to achieve, the seals of the hydraulic cylinders are prone to wear and failure, leading to oil leakage, internal leakage, and reduced efficiency. Hydraulic cylinder-driven pulley structures have a simple mechanical structure, but are difficult to balance, and also suffer from the problem of easily worn and failed hydraulic cylinder seals, resulting in oil leakage, internal leakage, and reduced efficiency. Crank-driven sheave structures offer simple and reliable reversing, but fail to effectively solve the balancing problem between two oil wells. Therefore, designing a reliable reversing, advanced and reliable balancing, and economical one-to-two pumping unit to overcome the shortcomings of the above-mentioned structures is of great practical significance. It is expected to achieve good field application results, thereby promoting the adoption of one-to-two oil production methods. This not only saves equipment investment but also reduces equipment wear and tear, saving energy and achieving economies of scale. By suspending a balance box on one of the levers of the one-to-two pumping unit, a traditional one-to-one pumping method can be achieved. Summary of the Invention

[0003] To address the problems existing in the prior art, this invention provides a pumping unit and a fluid balancing method. The purpose of this invention is to utilize the fluid's flowability to move the balancing medium. When used in a one-to-two oil production process, it can save the equipment investment of one pumping unit and reduce the operating losses of one pumping unit. It solves the balancing problem between the left and right wells of a one-to-two pumping unit, and the left and right flow of the balancing fluid has a double adjustment effect. It can also achieve precise balancing, eliminate the physical labor of balancing adjustment, and reduce the operating costs of balancing adjustment.

[0004] To solve the above-mentioned technical problems, the present invention provides a fluid balancing method, which uses fluid as the balancing medium. The balancing medium can flow in two chambers by utilizing the height difference or by being pumped by an electric pump.

[0005] The present invention also provides an oil pumping unit, comprising:

[0006] A base, on which a support seat is fixedly installed, and on which a motor and a reducer are fixedly installed, the motor and the reducer being connected by a belt;

[0007] A bracket, which is mounted on the support base;

[0008] A walking beam, wherein the walking beam is connected to the support base via the bracket;

[0009] The output shaft of the reducer is connected to the walking beam via a four-bar linkage; the two ends of the walking beam are respectively connected to a first donkey head and a second donkey head, and the first donkey head and the second donkey head are connected by a connecting pipe in the middle. An electric valve or an electric liquid pump is installed on the connecting pipe, and an electrical control box is also installed on the support base. The electrical control box is electrically connected to the electric valve or the electric liquid pump.

[0010] Furthermore, the four-bar linkage includes two cranks and two connecting rods. The two cranks are respectively connected to both ends of the output shaft of the reducer, and the two cranks are respectively connected to the walking beam through the two connecting rods.

[0011] Furthermore, the crank and the connecting rod are hinged together, and the connecting rod is hinged together with the walking beam.

[0012] Furthermore, the two ends of the connecting tube are respectively connected to the lower cavities of the first donkey head and the second donkey head.

[0013] Furthermore, a liquid inlet is provided on the connecting pipe near the bracket.

[0014] Furthermore, a suspension rope device is provided at the lower end of both the first and second donkey heads.

[0015] This invention also proposes a fluid balancing method, which utilizes the aforementioned pumping unit, and includes the following steps:

[0016] S1. Start the oil pumping unit;

[0017] S2. When the loads on the two ends of the walking beam are inconsistent, the walking beam is swung up and down through a four-bar linkage, so that the donkey head with the smaller load moves downward and the donkey head with the larger load moves upward.

[0018] S3. When the donkey head under light load moves to the lowest point, stop the motor and open the electric valve;

[0019] S4. At this point, the fluid will flow from the heavy-load donkey head to the light-load donkey head. After this is completed, the electric valve or electric pump will be turned off.

[0020] Furthermore, a fluid is used as the balancing medium, which can be drawn between the left and right donkey heads by utilizing the height difference or by an electric pump.

[0021] Furthermore, in step S2, the four-bar linkage includes two cranks and two connecting rods. The two cranks are respectively connected to both ends of the output shaft of the reducer, and the two cranks are respectively connected to the walking beam through the two connecting rods. The motor drives the reducer to move through the belt, and then drives the walking beam to swing up and down through the cranks and connecting rods.

[0022] Furthermore, when the fluid inside the donkey head decreases, antifreeze fluid is added to the first and second donkey heads through the filling port.

[0023] The present invention provides an oil pumping unit and a fluid balancing method, which have at least the following beneficial effects:

[0024] The pumping unit of this application adopts a double-donkey-head walking beam structure, with the first donkey head and the second donkey head each suspending the rod string or balance box of an oil well, so that one pumping unit can drive two oil wells to produce oil.

[0025] By connecting the lower chambers of the first and second donkey heads with a connecting pipe and installing an electric valve or electric pump on the connecting pipe, the left and right flow of the fluid is balanced, achieving double the adjustment effect. It can also achieve precise balance and eliminate the physical labor of balance adjustment, reducing the operation cost of balance adjustment.

[0026] By controlling the balance by making the fluid flow back and forth in the first donkey head, the second donkey head and the connecting pipe connecting the two, the influence of external factors on the fluid is reduced, thus making the adjustment of the balance more accurate and convenient.

[0027] By setting a filling port on the connecting pipe, antifreeze fluid can be filled into the lower chambers of the first and second donkey heads, and the filling amount can be controlled by an electric valve or an electric pump set on the connecting pipe. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the structure of an oil pumping unit according to an embodiment of the present invention;

[0029] Figure 2 This is a schematic flowchart of a fluid balance method according to an embodiment of the present invention;

[0030] In the diagram: 1. Electric motor; 2. Belt; 3. Reducer; 4. Four-bar linkage; 5. Suspension rope device; 6. First donkey head; 7. Walking beam; 8. Second donkey head; 9. Connecting pipe; 10. Liquid inlet; 11. Electric valve or electric liquid pump; 12. Electrical control box; 13. Support base; 14. Base. Detailed Implementation

[0031] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0032] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0033] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0034] To better understand the purpose, structure, and function of this invention, a fluid balancing method and an oil pumping unit of this invention will be further described in detail below with reference to the accompanying drawings.

[0035] Example 1

[0036] This invention provides a fluid balancing method that uses a fluid as the balancing medium. The balancing medium can flow between two chambers using a height difference or by being pumped by an electric pump. This method can be applied to suitable mechanical structures as needed.

[0037] Example 2

[0038] like Figure 1 As shown, the present invention provides an oil pumping unit, comprising:

[0039] A base 14, on which a support 13 is fixedly installed, and on which a motor 1 and a reducer 3 are fixedly installed, and the motor 1 and the reducer 3 are connected by a belt 2;

[0040] A bracket is mounted on the support base 13;

[0041] Walking beam 7, which is connected to the support base 13 via the bracket;

[0042] The output shaft of the reducer 3 is connected to the walking beam 5 via a four-bar linkage 4; the two ends of the walking beam 5 are respectively connected to a first donkey head 6 and a second donkey head 8, and the first donkey head 6 and the second donkey head 8 are connected by a connecting pipe 9 located in the middle, and an electric valve or an electric liquid pump 11 is provided on the connecting pipe 9, which is used to connect and cut off the flow of fluid; an electrical control box 12 is also provided on the support base 13, and the electrical control box 12 is electrically connected to the electric valve 11.

[0043] Example 3

[0044] like Figure 1 As shown, the present invention provides an oil pumping unit, comprising:

[0045] A base 14, on which a support 13 is fixedly installed, and on which a motor 1 and a reducer 3 are fixedly installed, and the motor 1 and the reducer 3 are connected by a belt 2;

[0046] A bracket is mounted on the support base 13;

[0047] Walking beam 7, which is connected to the support base 13 via the bracket;

[0048] The output shaft of the reducer 3 is connected to the walking beam 5 via a four-bar linkage 4; the two ends of the walking beam 5 are respectively connected to a first donkey head 6 and a second donkey head 8, and the first donkey head 6 and the second donkey head 8 are connected by a connecting pipe 9 located in the middle, and an electric valve 11 or an electric liquid pump is installed on the connecting pipe 9. An electric control box 12 is also installed on the support base 13, and the electric control box 12 is electrically connected to the electric valve 11 or the electric liquid pump.

[0049] The difference between this embodiment and Embodiment 2 is that:

[0050] The four-bar linkage 4 includes two cranks and two connecting rods. The two cranks are respectively connected to both ends of the output shaft of the reducer 3, and the two cranks are respectively connected to the walking beam 5 through the two connecting rods. The cranks and the connecting rods are hinged together, and the connecting rods are hinged together with the walking beam.

[0051] The two ends of the connecting pipe 9 are respectively connected to the lower parts of the first donkey head 6 and the second donkey head 8; a liquid inlet 10 is provided on the connecting pipe 9 near the bracket, through which antifreeze fluid can be input into the lower cavity of the first donkey head 6 and the second donkey head 8 as a balance adjustment mass;

[0052] A suspension rope device 5 is provided at the lower end of both the first donkey head 6 and the second donkey head 8, which can suspend the polished rod load or the balance box; in this real-time example, the suspension rope device 3 of the first donkey head 6 and the second donkey head 8 each suspends the oil production rod string of an oil well; if a balance box is configured on the second donkey head, it can be used for oil pumping of only one oil well, and the fluid balance is used for the weight difference between the oil well and the balance box.

[0053] Example 4

[0054] This invention provides a fluid balancing method, which utilizes the aforementioned oil pumping unit, and includes the following steps:

[0055] S1. Start the oil pumping unit;

[0056] S2. When the loads on the two ends of the walking beam are inconsistent, the walking beam is swung up and down through a four-bar linkage, so that the donkey head with the smaller load moves downward and the donkey head with the larger load moves upward.

[0057] S3. When the donkey head under light load moves to the lowest point, stop the motor and open the electric valve;

[0058] S4. At this point, the fluid will flow from the heavy-load donkey head to the light-load donkey head. After this is completed, the electric valve or electric pump will be turned off.

[0059] The fluid balance method uses fluid as the balance medium, which can be drawn between the left and right donkey heads by utilizing the height difference or by electric pump.

[0060] In step S2, the four-bar linkage includes two cranks and two connecting rods. The two cranks are respectively connected to both ends of the output shaft of the reducer, and the two cranks are respectively connected to the walking beam through the two connecting rods. The motor 1 drives the reducer 3 to move through the belt 2, and then drives the walking beam 5 to swing up and down through the cranks and connecting rods.

[0061] When the fluid in the donkey head decreases, antifreeze fluid can be added to the first donkey head 6 and the second donkey head 8 through the fluid inlet 10, and the filling amount can be controlled by the electric valve 11 or electric pump installed on the connecting pipe.

[0062] This invention utilizes the fluidity of fluids to solve the problem of balancing oil pumping units. When the fluid flows from left to right (or from right to left), the balancing weight on one side decreases by W, while the balancing weight on the other side increases by W, effectively achieving a double or 2W balancing effect. It can achieve precise balancing and eliminate the physical labor required for balancing, reducing the operating costs of balancing. When used in a one-to-two pumping unit, the fluid balance is unique; when used in a one-to-one pumping unit, the fluid balance is auxiliary and needs to be used in conjunction with a solid balancing medium with a higher specific gravity to form a two-phase balance.

[0063] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention can have various modifications and variations. Where there is no contradiction, the embodiments can be combined with each other to form new embodiments. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention are included within the protection scope of the present invention.

Claims

1. A fluid equilibrium method, characterized in that, A fluid is used as the balancing medium, which can flow between the two chambers by utilizing the height difference or by pumping.

2. An oil pumping unit, characterized in that, include: A base, on which a support seat is fixedly installed, and on which a motor and a reducer are fixedly installed, the motor and the reducer being connected by a belt; A bracket, which is mounted on the support base; A walking beam, wherein the walking beam is connected to the support base via the bracket; The output shaft of the reducer is connected to the walking beam via the crank and connecting rod of a four-bar linkage; the two ends of the walking beam are respectively connected to a first donkey head and a second donkey head, which are connected by a connecting pipe in the middle. An electric valve or an electric liquid pump is installed on the connecting pipe, and an electrical control box is also installed on the support base. The electrical control box is electrically connected to the electric valve or the electric liquid pump.

3. The oil pumping unit according to claim 2, characterized in that, The four-bar linkage includes two cranks and two connecting rods. The two cranks are respectively connected to both ends of the output shaft of the reducer, and the two cranks are respectively connected to the walking beam through the two connecting rods.

4. The oil pumping unit according to claim 3, characterized in that, The crank and the connecting rod are hinged together, and the connecting rod is hinged together with the walking beam.

5. The oil pumping unit according to claim 2, characterized in that, The two ends of the connecting tube are respectively connected to the lower cavities of the first donkey head and the second donkey head.

6. The oil pumping unit according to claim 2, characterized in that, A liquid inlet is provided on the connecting pipe near the bracket.

7. The oil pumping unit according to claim 2, characterized in that, A suspension rope device is provided at the lower end of both the first and second donkey heads.

8. A fluid balancing method, implemented using an oil pumping unit as described in any one of claims 2 to 7, characterized in that it comprises the following steps: S1. Start the oil pumping unit; S2. When the loads on the donkey heads at both ends of the walking beam are inconsistent or unbalanced, the walking beam is swung up and down through a four-bar linkage, causing the donkey head with the smaller load to move downward and the donkey head with the larger load to move upward. S3. When the donkey head under light load moves to the lowest point, stop the motor and open the electric valve; S4. At this point, the fluid will flow from the heavy-load donkey head to the light-load donkey head. After this is completed, the electric valve or electric pump will be turned off.

9. The fluid equilibrium method according to claim 8, characterized in that, A fluid is used as the balancing medium, which can be drawn between the left and right donkey heads by utilizing the height difference or by an electric pump.

10. The fluid equilibrium method according to claim 8, characterized in that, In step S2, the four-bar linkage includes two cranks and two connecting rods. The two cranks are respectively connected to both ends of the output shaft of the reducer, and the two cranks are respectively connected to the walking beam through the two connecting rods. The motor drives the reducer to move through the belt, and then drives the walking beam to swing up and down through the cranks and connecting rods.

11. The fluid equilibrium method according to claim 8, characterized in that, When the fluid inside the donkey's head decreases, add antifreeze fluid to the first and second donkey heads.

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