A stirring oil pumping device and method

Abstract

The present invention discloses a stirring oil pumping device and method, wherein the device comprises a pump barrel assembly and a plunger assembly, wherein the plunger assembly axially runs in the pump barrel, and an oil inlet valve and an oil outlet valve are installed inside the plunger assembly, wherein the oil outlet valve is located above the oil inlet valve, and the oil inlet valve is installed inside the lower port of the plunger assembly, and the lower end of the oil inlet valve is connected to a stirring device. The present invention improves the structure of a conventional oil pump, moves the oil inlet valve of the pump upward to the lower end of the plunger, and directly connects the lower end of the oil inlet valve to the stirring device, forming a pumping technology for mixing and adding medicine under the pump.

Description

Technical Field

[0001] The invention relates to oil production technology, in particular to a stirring oil pumping device and method. Background Art

[0002] In the development of oil wells that require the addition of chemicals, conventional oil pumps cannot achieve pump stirring, and the crude oil under the pump cannot be fully mixed with the chemicals, resulting in the chemicals not being able to work efficiently. This not only wastes some of the chemicals, increases investment costs, but also affects pump efficiency. At present, there are two ways to add chemicals to the pump in the mine: (1) Add from the casing gate through the oil casing annulus to the pump, and use a conventional oil pump with a solid sucker rod string; this method does not increase the investment in downhole tools such as sucker rod strings, and can also be added at any time according to production needs. It has strong on-site operability and is the main way to add chemicals to the wellbore. (2) Add to the pump through a matching hollow rod, sliding valve oil pump or offset oil pump. This method increases investment costs because of the matching of hollow rods and special pumps. Although both methods can add chemicals to the pump, the added chemicals float above the dynamic liquid surface of the crude oil and are difficult to reach the suction port of the oil pump. It is impossible to achieve uniform pumping, achieve the ideal viscosity reduction effect, and effectively reduce the load of the pumping unit.

[0003] Application number: 201710946618.0, publication date 2017-12-19 discloses a pump-type viscosity-reducing agitator, wherein a fixed wheel shaft hole is drilled horizontally on a semi-cylindrical impeller frame, an impeller groove is provided on the semi-cylindrical impeller frame, and hoop spring grooves are provided at the upper and lower ends of the semi-cylindrical impeller frame. The middle of the impeller is a hyperbolic cylinder, and blades are provided at both ends of the impeller. Rotating wheel shaft holes are drilled on both end surfaces of the impeller, and the impeller is placed in the impeller groove. The impeller is inserted into the fixed wheel shaft hole and the impeller. The axle in the rotating axle hole is installed on the impeller frame. After the two impeller frames with impellers installed are closed, a hoop spring is installed in each of the two hoop spring grooves to make them integrated and then placed in the upper part of the lower joint. The lower part of the upper joint is connected with the upper part of the lower joint, and the hollow rod is inserted into the upper joint and passes through the lower joint. The inner sides of the two impellers are close to the hollow rod, so that the hollow rod can drive the impeller to rotate, and the viscosity reducer injected from the hollow rod can be stirred here when it flows upward together with the well fluid, so that the viscosity reducer and the well fluid are mixed and evenly mixed.

[0004] There are many ways to reduce viscosity by pumping. Any reagent can be added in this application. The structure of the pump and stirring device is different from the prior art. Summary of the invention

[0005] The purpose of the present invention is to provide a stirring oil pumping device and method, which improves the structure of a conventional oil pump, moves the oil inlet valve of the pump up to the lower end of the plunger, and directly connects the lower end of the oil inlet valve to the stirring device, forming a viscosity reduction oil pumping technology with stirring and mixing under the pump.

[0006] In order to achieve the above-mentioned purpose, the present invention provides the following technical solutions: a stirring oil pumping device, including a pump barrel assembly and a plunger assembly, wherein the plunger assembly runs axially in the pump barrel, and an oil inlet valve and an oil outlet valve are installed inside the plunger assembly, wherein the oil outlet valve is located above the oil inlet valve, and the oil inlet valve is installed inside the lower port of the plunger assembly, and the lower end of the oil inlet valve is connected to a stirring device. The stirring device includes a barrel tube body, wherein the outer wall of the barrel tube body is provided with a stirring spiral groove, and a radially penetrating exchange hole is provided in the stirring spiral groove, the lower end of the barrel tube body is a blocking end, and the lower end of the barrel tube body is conical, and the upper end of the barrel tube body is a threaded connection end.

[0007] The pump barrel assembly includes an upper pump barrel and a lower pump barrel, and the plunger assembly includes an upper plunger and a lower plunger. The upper plunger is located in the upper pump barrel, and the lower plunger is located in the lower pump barrel. The lower port of the upper plunger is connected to the upper port of the lower plunger, and the lower port of the upper pump barrel is connected to the upper port of the lower pump barrel. The diameter of the upper plunger is smaller than the diameter of the lower plunger, and the inner diameter of the upper pump barrel is smaller than the inner diameter of the lower pump barrel; the oil inlet valve is installed inside the lower port of the lower plunger, and the oil outlet valve is installed inside the upper plunger.

[0008] A radially penetrating oil storage inlet and outlet hole is provided at the upper end of the lower plunger, and a radially penetrating oil outlet hole is provided at the upper end of the upper plunger. The positions of the oil storage inlet and outlet holes are higher than the oil inlet valve and lower than the oil outlet valve, and the position of the oil outlet hole is higher than the oil outlet valve.

[0009] A plunger necking platform is formed at the connection between the lower port of the upper plunger and the upper port of the lower plunger, and a pump barrel necking platform is formed at the connection between the lower port of the upper pump barrel and the upper port of the lower pump barrel. The pump barrel necking platform forms an axial limit for the plunger necking platform. A limit ring is installed on the inner wall of the lower pump barrel, and the upper end of the limit ring faces the lower end of the lower plunger to form an axial limit.

[0010] In the inner cavity of the lower pump barrel, the space between the plunger necking platform and the pump barrel necking platform forms a variable cavity.

[0011] In order to achieve the above another object, the present invention provides the following technical solution, a stirring oil pumping method, comprising the following steps:

[0012] The reagent enters the casing from the casing gate through the casing annulus and the reagent inlet on the casing to mix with the crude oil. Then the crude oil with the reagent rises to the bottom of the pump and directly enters the stirring device. The stirring device is directly connected to the lower end of the oil inlet valve. With the up and down movement of the sucker rod, the stirring device stirs and mixes the crude oil under the pump with the reagent to reduce the viscosity of the crude oil. The stirred reduced-viscosity crude oil enters the oil pump for downstroke and upstroke.

[0013] The downstroke is the process of the oil pump filling the oil well: the sucker rod and the pull rod drive the upper plunger and the lower plunger to move downward from the top dead center to the lower limit point, that is, the lower plunger moves to the limit position; in this process, the variable chamber, that is, the A chamber, increases in volume and the pressure decreases, the oil outlet valve is closed because the internal pressure of the pump chamber is less than the external pressure, and the oil inlet valve is opened because the external pressure is greater than the internal pressure of the pump chamber, and the mixed liquid of the reagent and crude oil after stirring directly enters the pump chamber; at the same time, the pressure of the liquid column in the wellbore acts on the plunger assembly in a downward direction, forming a downward feedback force;

[0014] The upstroke is the discharge process of the oil pump: the sucker rod string and the pull rod drive the upper plunger and the lower plunger to move upward from the bottom dead center to the upper limit position; in this process, the volume of the variable chamber, i.e., chamber A, becomes smaller, the pressure increases, the oil inlet valve is closed due to the internal pressure of the pump chamber being greater than the external pressure, and the oil outlet valve is opened due to the internal pressure of the pump chamber, and the oil pump discharges liquid.

[0015] Compared with the prior art, the present invention has the following beneficial effects:

[0016] The reagent is added to the pump from the casing gate through the casing annulus. The stirring device is directly connected to the lower end of the oil inlet valve. With the up and down movement of the sucker rod, the crude oil and the reagent are stirred and mixed under the pump to reduce the viscosity of the crude oil. During the downstroke, the volume of the variable chamber, i.e., chamber A, becomes larger, the pressure decreases, the oil inlet valve opens, the oil outlet valve closes, the mixed liquid enters the pump chamber, and the liquid column pressure in the upper tubing of the pump acts on the plunger to form a downward feedback force. During the upstroke, the volume of the variable chamber, i.e., chamber A, becomes smaller, the pressure increases, the oil inlet valve closes, the oil outlet valve opens, and the pump discharges liquid.

[0017] There is no fixed valve at the lower end of the oil pump barrel, the oil inlet valve of the pump is moved up to the lower end of the plunger, and the lower end of the oil inlet valve is directly connected to the stirring device.

[0018] The double plunger series structure with a small top and a large bottom can provide feedback force for the plunger to go down, effectively solving the problem of difficulty in rod string going down in heavy oil wells.

[0019] The present invention can be applied to heavy oil wells to reduce viscosity by adding chemicals, effectively solving the problem of high viscosity of crude oil in wellbore and difficulty in extracting liquid, and can replace wellbore viscosity reduction methods such as electric heating to improve pump efficiency and reduce costs. It can also be applied to adding corrosion inhibitors and scale inhibitors to the annulus of oil casings in corrosive wells and scaling wells to enhance the anti-corrosion and anti-scaling performance of corrosion inhibitors and scale inhibitors. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a structural cross-sectional view of a stirring oil pumping device of the present invention during a downstroke;

[0021] Figure 2 This is a structural cross-sectional view of a stirring oil pumping device of the present invention during an upstroke;

[0022] Figure 3 Schematic diagram of the stirring device.

[0023] In the figure: pull rod 1, upper pump barrel 2, upper plunger 3, oil outlet valve 4, oil inlet valve 5, lower plunger 6, lower pump barrel 7, stirring device 8, limit ring 9. DETAILED DESCRIPTION

[0024] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0025] See also Figures 1 to 3 The present invention provides a technical solution: a stirring oil pumping device, including a pump barrel assembly and a plunger assembly, wherein the plunger assembly runs axially in the pump barrel, and an oil inlet valve 5 and an oil outlet valve 4 are installed inside the plunger assembly, wherein the oil outlet valve is located above the oil inlet valve, and the oil inlet valve is installed inside the lower port of the plunger assembly, and the lower end of the oil inlet valve is connected to a stirring device 8.

[0026] The stirring device comprises a barrel tube body, the outer wall of the barrel tube body is provided with a stirring spiral groove, a radially penetrating exchange hole is provided in the stirring spiral groove, the lower end of the barrel tube body is a blocking end, the lower end of the barrel tube body is conical, and the upper end of the barrel tube body is a threaded connection end. The spiral groove is milled out by a milling machine according to a certain width, height, and spacing, and the groove part is evenly distributed with holes, so that the reagent and the crude oil can be exchanged at the hole position to improve the stirring effect.

[0027] The pump barrel assembly includes an upper pump barrel 2 and a lower pump barrel 7, and the plunger assembly includes an upper plunger 3 and a lower plunger 6. The upper plunger is located in the upper pump barrel, and the lower plunger is located in the lower pump barrel. The lower port of the upper plunger is connected to the upper port of the lower plunger, and the lower port of the upper pump barrel is connected to the upper port of the lower pump barrel. The diameter of the upper plunger is smaller than the diameter of the lower plunger, and the inner diameter of the upper pump barrel is smaller than the inner diameter of the lower pump barrel. The oil inlet valve is installed inside the lower port of the lower plunger, and the oil outlet valve is installed inside the upper plunger. The upper end of the upper pump barrel is connected to the sleeve, the lower end of the lower pump barrel is connected to the sleeve, the upper end of the upper plunger is connected to the pull rod, and the lower end of the lower plunger is connected to the oil pipe.

[0028] A radially penetrating oil storage inlet and outlet hole is provided at the upper end of the lower plunger, and a radially penetrating oil outlet hole is provided at the upper end of the upper plunger. The positions of the oil storage inlet and outlet holes are higher than the oil inlet valve 5 and lower than the oil outlet valve 4. The position of the oil outlet hole is higher than the oil outlet valve 4.

[0029] A plunger necking platform is formed at the connection between the lower port of the upper plunger and the upper port of the lower plunger, and a pump barrel necking platform is formed at the connection between the lower port of the upper pump barrel and the upper port of the lower pump barrel. The pump barrel necking platform forms an axial limit for the plunger necking platform. A limit ring 9 is installed on the inner wall of the lower pump barrel, and the upper end of the limit ring faces the lower end of the lower plunger to form an axial limit.

[0030] In the inner cavity of the lower pump barrel, the space between the plunger necking platform and the pump barrel necking platform forms a variable cavity, namely cavity A in the drawing.

[0031] The upper end of the pull rod 1 is connected to the sucker rod column, the lower end of the pull rod 1 is connected to the upper plunger 3, the lower end of the upper plunger 3 is connected to the lower plunger 6, the oil outlet valve 4 is assembled in the upper plunger 3, the upper pump barrel 2 is connected to the lower pump barrel 7, the upper plunger 3 is placed in the upper pump barrel 2, the oil inlet valve 5 is assembled in the lower plunger 6, the lower plunger 6 is placed in the lower pump barrel 7, and the stirring device 8 is directly connected to the lower end of the oil inlet valve 5.

[0032] The mixed liquid entering the oil pump is stirred to reduce viscosity: the reagent is added to the pump from the casing gate through the casing annulus, and the stirring device 8 is directly connected to the lower end of the oil inlet valve 5. With the up and down movement of the sucker rod, the crude oil and the reagent under the pump are stirred and mixed, thereby improving the stirring effect.

[0033] Down stroke (such as Figure 1 ), which is the process of the oil pump filling liquid: the sucker rod column and the tie rod 1 drive the upper plunger 3 and the lower plunger 6 to move downward from the top dead center to the bottom dead center, that is, the lower plunger 6 moves to the limit 9. In this process, the volume of the A cavity composed of the upper plunger 3, the upper pump barrel 2, the lower plunger 6, and the lower pump barrel 7 increases, and the pressure decreases. The internal pressure of the pump cavity of the oil outlet valve 4 is less than the external pressure and is closed, and the external pressure of the oil inlet valve 5 is greater than the internal pressure of the pump cavity and is opened. The mixed liquid of the agent and crude oil after stirring directly enters the pump cavity; at the same time, the pressure of the liquid column in the wellbore acts on the plunger (upper plunger 3 and lower plunger 6) in a downward direction, forming a downward feedback force.

[0034] Upstroke (such as Figure 2 ), which is the discharge process of the oil pump: the sucker rod string and the tie rod 1 drive the upper plunger 3 and the lower plunger 6 to move upward from the bottom dead center to the top dead center. In this process, the volume of the A cavity formed by the upper plunger 3, the upper pump barrel 2, and the lower pump barrel 7 becomes smaller, and the pressure increases. The internal pressure of the pump chamber of the oil inlet valve 5 is greater than the external pressure and is closed, and the internal pressure of the pump chamber of the oil outlet valve 4 is opened, and the oil pump discharges.

[0035] There is no fixed valve at the lower end of the oil pump barrel, the oil inlet valve of the pump is moved up to the lower end of the plunger, and the lower end of the oil inlet valve is directly connected to the stirring device.

[0036] The double plunger series structure with a small top and a large bottom can provide feedback force for the plunger to go down, effectively solving the problem of difficulty in rod string going down in heavy oil wells.

[0037] The present invention can be applied to oil well dosing, effectively solving the problem of large amount of wellbore chemicals and difficulty in extracting liquid, and can replace wellbore viscosity reduction methods such as electric heating to improve pump efficiency and reduce costs. It can also be applied to adding corrosion inhibitors and scale inhibitors to the annulus of oil casings in corrosive wells and scaling wells to enhance the anti-corrosion and anti-scaling performance of corrosion inhibitors and scale inhibitors.

[0038] In the description of the present invention, it is necessary to understand that the orientation indications or positional relationships are based on the orientations or positional relationships shown in the drawings and are only for the convenience of describing the present invention, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0039] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A stirring oil pumping device, comprising a pump barrel assembly and a plunger assembly, wherein the plunger assembly axially runs in the pump barrel, and an oil inlet valve and an oil outlet valve are installed inside the plunger assembly, wherein the oil outlet valve is located above the oil inlet valve, and is characterized in that: The oil inlet valve is installed inside the lower port of the plunger assembly, and the lower end of the oil inlet valve is connected to the stirring device, and the stirring device includes a barrel tube body, the outer wall of the barrel tube body is provided with a stirring spiral groove, and a radially penetrating exchange hole is provided in the stirring spiral groove, the lower end of the barrel tube body is a blocking end, and the lower end of the barrel tube body is conical, and the upper end of the barrel tube body is a threaded connection end; The pump barrel assembly includes an upper pump barrel and a lower pump barrel, and the plunger assembly includes an upper plunger and a lower plunger. The upper plunger is located in the upper pump barrel, and the lower plunger is located in the lower pump barrel. The lower port of the upper plunger is connected to the upper port of the lower plunger, and the lower port of the upper pump barrel is connected to the upper port of the lower pump barrel. The diameter of the upper plunger is smaller than the diameter of the lower plunger, and the inner diameter of the upper pump barrel is smaller than the inner diameter of the lower pump barrel. The oil inlet valve is installed inside the lower port of the lower plunger, and the oil outlet valve is installed inside the upper plunger. The upper end of the upper pump barrel is connected to the sleeve, and the lower end of the lower pump barrel is connected to the sleeve. The upper end of the upper plunger is connected to the pull rod, and the lower end of the lower plunger is connected to the oil pipe. A radially penetrating oil storage inlet and outlet hole is provided at the upper end of the lower plunger, and a radially penetrating oil outlet hole is provided at the upper end of the upper plunger. The positions of the oil storage inlet and outlet holes are higher than the oil inlet valve and lower than the oil outlet valve, and the position of the oil outlet hole is higher than the oil outlet valve.

2. The stirring oil pumping device according to claim 1, characterized in that: A plunger necking platform is formed at the connection between the lower port of the upper plunger and the upper port of the lower plunger, and a pump barrel necking platform is formed at the connection between the lower port of the upper pump barrel and the upper port of the lower pump barrel. The pump barrel necking platform forms an axial limit for the plunger necking platform. A limit ring is installed on the inner wall of the lower pump barrel, and the upper end of the limit ring faces the lower end of the lower plunger to form an axial limit.

3. The stirring oil pumping device according to claim 2, characterized in that: In the inner cavity of the lower pump barrel, the space between the plunger necking platform and the pump barrel necking platform forms a variable cavity.

4. A stirring oil pumping method using the stirring oil pumping device as claimed in claim 1, characterized in that: The following steps are involved: The reagent enters the casing from the casing gate through the casing annulus and the reagent inlet on the casing to mix with the crude oil. Then the crude oil with the reagent rises to the bottom of the pump and directly reaches the stirring device. The stirring device is directly connected to the lower end of the oil inlet valve. With the up and down movement of the sucker rod, the stirring device stirs and mixes the crude oil and the reagent under the pump to improve the mixing effect of the reagent and the crude oil. The stirred crude oil containing the reagent enters the oil pump for downstroke and upstroke. The downstroke is the process of the oil pump filling the oil well: the sucker rod and the tie rod drive the upper plunger and the lower plunger to move downward from the top dead center to the lower limit position, that is, the lower plunger moves to the limit position; in this process, the variable chamber, that is, the A chamber, increases in volume and the pressure decreases, the oil outlet valve is closed because the internal pressure of the pump chamber is less than the external pressure, and the oil inlet valve is opened because the external pressure is greater than the internal pressure of the pump chamber, and the mixed liquid of the reagent and crude oil after stirring directly enters the pump chamber; At the same time, the pressure of the liquid column in the wellbore acts on the plunger assembly in a downward direction, forming a downward feedback force; The upstroke is the discharge process of the oil pump: the sucker rod string and the pull rod drive the upper plunger and the lower plunger to move upward from the bottom dead center to the upper limit position; in this process, the volume of the variable chamber, i.e., chamber A, becomes smaller, the pressure increases, the oil inlet valve is closed due to the internal pressure of the pump chamber being greater than the external pressure, and the oil outlet valve is opened due to the internal pressure of the pump chamber, and the oil pump discharges liquid.

Images