阅读说明：本技术 用于高含气井的螺杆泵组 (Screw pump set for high-gas-content well ) 是由 池胜高 李盛华 李松 邹艳 卢显圣 于 2019-09-18 设计创作，主要内容包括：本发明公开了一种用于高含气井的螺杆泵组,由下螺杆泵、上螺杆泵、柔性轴组成。下螺杆泵的定子底端连接第一尾管,第一尾管侧壁上开设多个第一通孔,下螺杆泵的转子的下端插入第一尾管的部位的侧壁的至少一侧呈竖直平面的形状；上螺杆泵的定子底端连接第二尾管,第二尾管侧壁上开设多个第二通孔,上螺杆泵的转子的下端插入第二尾管的部位的侧壁的至少一侧呈竖直平面的形状；第二尾管的底端固定于下螺杆泵的定子的顶端,柔性轴两端分别与下螺杆泵的转子、上螺杆泵的转子连接。本发明具有减少或去除高含气原油所含的气体的有益效果,从而获得低含气或不含气的原油,同时具有螺杆泵能耗低、适应性强的优点。(The invention discloses a screw pump set for a high-gas-content well, which consists of a lower screw pump, an upper screw pump and a flexible shaft. The bottom end of a stator of the lower screw pump is connected with a first tail pipe, a plurality of first through holes are formed in the side wall of the first tail pipe, and at least one side of the side wall of the part, inserted into the first tail pipe, of the lower end of a rotor of the lower screw pump is in a vertical plane shape; the bottom end of a stator of the upper screw pump is connected with a second tail pipe, a plurality of second through holes are formed in the side wall of the second tail pipe, and at least one side of the side wall of the part, inserted into the second tail pipe, of the lower end of a rotor of the upper screw pump is in a vertical plane shape; the bottom end of the second tail pipe is fixed at the top end of a stator of the lower screw pump, and two ends of the flexible shaft are respectively connected with a rotor of the lower screw pump and a rotor of the upper screw pump. The invention has the beneficial effect of reducing or removing the gas contained in the crude oil with high gas content, thereby obtaining the crude oil with low gas content or without gas, and simultaneously has the advantages of low energy consumption and strong adaptability of the screw pump.)

1. Screw pump group for high gas-containing wells, characterized in that it comprises:

a lower screw pump, comprising:

the top end of the first tail pipe is fixed at the bottom end of the stator of the lower screw pump and is coaxially arranged with the stator of the lower screw pump, a plurality of first through holes are formed in the side wall of the first tail pipe, the size of each first through hole is 3-20 mm, the lower end of a rotor of the lower screw pump is inserted into the first tail pipe, and at least one side of the side wall of the part, located in the first tail pipe, of the rotor of the lower screw pump is in a vertical plane shape;

go up the screw pump, go up the stator of screw pump with the coaxial setting of stator of screw pump down, it includes to go up the screw pump:

the top end of the second tail pipe is fixed at the bottom end of the stator of the upper screw pump and is coaxially arranged with the stator of the upper screw pump, the bottom end of the second tail pipe is fixed at the top end of the stator of the lower screw pump, the side wall of the second tail pipe is provided with a plurality of second through holes, the size of each second through hole is 3-20 mm, the lower end of a rotor of the upper screw pump is inserted into the second tail pipe, and at least one side of the side wall of the part, located in the second tail pipe, of the rotor of the upper screw pump is in a vertical plane shape; the flexible shaft is arranged in the stator of the lower screw pump and the second tail pipe, the lower end of the flexible shaft is connected with the top end of the rotor of the lower screw pump, and the upper end of the flexible shaft is connected with the bottom end of the rotor of the upper screw pump; wherein the displacement of the lower screw pump is more than 2 times of the displacement of the upper screw pump.

2. Screw pump group for high gas wells according to claim 1, characterized in that the vertical planes of the side walls of the lower screw pump rotor at the location of the first tailpipe are two and parallel to each other.

3. Screw pump group for high gas wells according to claim 2, characterized in that the vertical planes of the side walls of the lower end of the rotors of the upper screw pump at the location of the second tailpipe are two and parallel to each other.

4. The screw pump group for a high gas content well according to claim 1, wherein the first through holes are circular holes, a plurality of first through holes are arranged in a plurality of rows along the circumferential direction of the first tail pipe, the radian of an arc line formed between two adjacent first through holes on the same circumference is 36-60 °, and the vertical distance between two adjacent first through holes on the same row is more than 3 times the aperture of the first through holes.

5. The screw pump group for a high gas well according to claim 4, wherein the second through holes are circular holes, a plurality of second through holes are arranged in a plurality of rows along the circumferential direction of the second tail pipe, the radian of an arc line formed between two adjacent second through holes on the same circumference is 36-60 degrees, and the vertical distance between two adjacent second through holes on the same row is more than 3 times the diameter of the second through holes.

6. Screw pump package for high gas well according to claim 1, characterized in that the bottom of the first tail pipe is provided with a limit pin, the middle part of the limit pin is provided with an oil flow hole, and the diameter of the oil flow hole is smaller than the size of the bottom surface of the rotor of the lower screw pump.

7. The screw pump set for the high gas well as recited in claim 1, wherein a limit pin is disposed at the bottom of the first tail pipe, a funnel-shaped circular hole is formed in the middle of the limit pin, the aperture of the upper opening of the funnel-shaped circular hole is larger than the aperture of the lower opening of the funnel-shaped circular hole, a pair of holes with semicircular cross sections are formed in the two sides of the limit pin, the pair of holes with semicircular cross sections are not communicated with each other, and the aperture of the lower opening of the funnel-shaped circular hole is smaller than the size of the bottom surface of the rotor of the lower screw pump.

8. Screw pump package for high gas well according to claim 1, characterised in that the bottom end of the second tailpipe is connected to the top end of the stator of the lower screw pump by means of a screw thread.

9. Screw pump package for high gas well according to claim 1 characterized in that both ends of the flexible shaft are connected with the top end of the rotor of the lower screw pump and the bottom end of the rotor of the upper screw pump by screw threads.

Technical Field

The invention relates to the technical field of petroleum and natural gas drilling and production equipment. More particularly, the invention relates to a screw pump set for a high-gas-containing well.

Background

The screw pump oil production system has the advantages of being suitable for thick oil wells, sand-containing wells, low-yield oil wells and middle and later period water-drive, polymer-drive and ternary-drive oil wells. However, when the crude oil contains a large amount of gas, the advantage of screw pump oil production is limited. On-site tests and laboratory tests show that the gas void ratio can reduce the volumetric efficiency of the screw pump, and extremely small local stress and heating are generated in the stator elastomer, so that the rotation torque is increased, the mechanical property of the stator elastomer is deteriorated, and finally the service life of the screw pump is reduced. Although static and dynamic downhole separators have been developed, in many cases, the efficiency of gas-liquid separation is very poor due to the extremely high viscosity of the fluid and the manner in which the gas is dispersed in the liquid matrix (the foam oil effect), and therefore, a screw pump device that effectively separates the above-mentioned fluid from the gas is currently required.

Disclosure of Invention

An object of the present invention is to solve at least the above problems and to provide at least the advantages described later.

The invention also aims to provide a screw pump set for a high gas-containing well, which is used for stirring high gas-containing crude oil in an oil extraction system to realize two-stage gas-liquid separation of the crude oil and achieve the beneficial effect of reducing or removing gas contained in the crude oil, so that the low gas-containing or gas-free crude oil is obtained, and meanwhile, the screw pump set has the advantages of low energy consumption and strong adaptability.

To achieve these objects and other advantages and in accordance with the purpose of the invention, there is provided a screw pump set for a high gas containing well, comprising:

a lower screw pump, comprising:

the top end of the first tail pipe is fixed at the bottom end of the stator of the lower screw pump and is coaxially arranged with the stator of the lower screw pump, a plurality of first through holes are formed in the side wall of the first tail pipe, the size of each first through hole is 3-20 mm, the lower end of a rotor of the lower screw pump is inserted into the first tail pipe, and at least one side of the side wall of the part, located in the first tail pipe, of the rotor of the lower screw pump is in a vertical plane shape;

go up the screw pump, go up the stator of screw pump with the coaxial setting of stator of screw pump down, it includes to go up the screw pump:

the top end of the second tail pipe is fixed at the bottom end of the stator of the upper screw pump and is coaxially arranged with the stator of the upper screw pump, the bottom end of the second tail pipe is fixed at the top end of the stator of the lower screw pump, the side wall of the second tail pipe is provided with a plurality of second through holes, the size of each second through hole is 3-20 mm, the lower end of a rotor of the upper screw pump is inserted into the second tail pipe, and at least one side of the side wall of the part, located in the second tail pipe, of the rotor of the upper screw pump is in a vertical plane shape;

the flexible shaft is arranged in the stator of the lower screw pump and the second tail pipe, the lower end of the flexible shaft is connected with the top end of the rotor of the lower screw pump, and the upper end of the flexible shaft is connected with the bottom end of the rotor of the upper screw pump;

wherein the displacement of the lower screw pump is more than 2 times of the displacement of the upper screw pump.

Preferably, the lower end of the rotor of the lower screw pump is located on two vertical planes of the side wall of the first tail pipe, and the two vertical planes are parallel to each other.

Preferably, the two vertical planes of the side wall of the lower end of the rotor of the upper screw pump at the position of the second tail pipe are parallel to each other.

Preferably, the first through holes are round holes, the plurality of first through holes are arranged in multiple rows along the circumferential direction of the first tail pipe, the radian of an arc line formed between two adjacent first through holes on the same circumference is 36-60 degrees, and the vertical distance between two adjacent first through holes on the same row is more than 3 times the aperture of each first through hole.

Preferably, the second through holes are round holes, the plurality of second through holes are arranged in multiple rows along the circumferential direction of the second tail pipe, the radian of an arc line formed between every two adjacent second through holes on the same circumference is 36-60 degrees, and the vertical distance between every two adjacent second through holes on the same row is more than 3 times the aperture of each second through hole.

Preferably, the bottom of the first tail pipe is provided with a limit pin, the middle part of the limit pin is provided with an oil flow hole, and the aperture of the oil flow hole is smaller than the size of the bottom surface of the rotor of the lower screw pump.

Preferably, the bottom of first tail pipe is equipped with the spacer pin, funnel-shaped round hole has been seted up at the spacer pin middle part, the last open-ended aperture that leaks funnel-shaped round hole is greater than the lower shed's of funnel-shaped round hole aperture, the spacer pin is located a pair of transverse section is semicircular ring's hole has been seted up to the both sides of leaking funnel-shaped round hole, and a pair of transverse section is not communicated between the semicircular ring's the hole, the lower shed's of funnel-shaped round hole aperture is less than the size of the bottom surface of the rotor of screw pump down.

Preferably, the bottom end of the second tail pipe is connected with the top end of the stator of the lower screw pump in a threaded manner.

Preferably, the two ends of the flexible shaft are in threaded connection with the top end of the rotor of the lower screw pump and the bottom end of the rotor of the upper screw pump.

The invention at least comprises the following beneficial effects:

screw pump set capable of being applied to gas-liquid ratio of more than 100m³/m³The high gas content crude oil is stirred in an oil extraction system, so that two-stage gas-liquid separation of the crude oil is realized, and gas contained in the crude oil is reduced or removed, thereby obtaining the crude oil with low gas content or without gas;

secondly, the screw pump set has the advantages of low energy consumption and strong adaptability of the screw pump;

thirdly, funnel-shaped round hole has been seted up at the spacer pin middle part of screw pump package, and funnel-shaped round hole's both sides have been seted up on the spacer pin and have been seted up a pair of transverse section and be the hole that does not communicate of semicircle annular, have the beneficial effect of sand control, can avoid sand blocking, reduce the equipment abrasion, play the effect of protective apparatus and assurance oil recovery speed.

Additional advantages, objects, and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention.

Drawings

FIG. 1 is a longitudinal section of the screw pump set for high gas-containing wells according to one embodiment of the invention;

FIG. 2 is a schematic structural view of a rotor of the lower screw pump according to one embodiment of the present invention;

FIG. 3 is a detailed view of the first tailpipe of one embodiment of the present invention;

fig. 4 is a schematic structural view of the limit pin according to one embodiment of the present invention;

fig. 5 is a longitudinal sectional view of the stopper pin according to one embodiment of the present invention.

Detailed Description

The present invention is further described in detail below with reference to the attached drawings so that those skilled in the art can implement the invention by referring to the description text.

It should be noted that in the description of the present invention, the indicated orientation or positional relationship is based on the orientation or positional relationship shown in the drawings, and is only for convenience of describing the present invention and simplifying the description, and does not indicate or imply that the indicated device or element must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention.

As shown in fig. 1 to 5, the present invention provides a screw pump set for a high gas-containing well, comprising:

a lower screw pump, comprising:

a first tail pipe 7, the top end of which is fixed at the bottom end of a stator 6 of the lower screw pump and is coaxially arranged with the stator 5 of the lower screw pump, the side wall of the first tail pipe 7 is provided with a plurality of first through holes 10, the size of the first through holes 10 is 3-20 mm, wherein the lower end of a rotor 5 of the lower screw pump is inserted into the first tail pipe 7, and at least one side of the side wall of the part of the rotor 5 of the lower screw pump, which is positioned in the first tail pipe 7, is in a vertical plane shape 9;

go up the screw pump, go up the stator 2 of screw pump with the stator 6 coaxial settings of screw pump down, go up the screw pump and include:

the top end of the second tail pipe 3 is fixed at the bottom end of the stator 2 of the upper screw pump and is coaxially arranged with the stator 1 of the upper screw pump, the bottom end of the second tail pipe 3 is fixed at the top end of the stator 6 of the lower screw pump, a plurality of second through holes 12 are formed in the side wall of the second tail pipe 3, the size of each second through hole 12 is 3-20 mm, the lower end of the rotor 1 of the upper screw pump is inserted into the second tail pipe 3, and at least one side of the side wall of the part, located in the second tail pipe 3, of the rotor 1 of the upper screw pump is in a vertical plane shape 11;

the flexible shaft 4 is arranged in the stator 6 of the lower screw pump and the second tail pipe 3, the lower end of the flexible shaft 4 is connected with the top end of the rotor 5 of the lower screw pump, and the upper end of the flexible shaft 4 is connected with the bottom end of the rotor 1 of the upper screw pump;

wherein the displacement of the lower screw pump is more than 2 times of the displacement of the upper screw pump.

In the technical scheme, the ground driving device drives the rotor of the upper screw pump to rotate through the sucker rod, and the rotor of the upper screw pump drives the rotor of the lower screw pump to rotate through the flexible shaft. The high gas content crude oil flows into the first tail pipe of the lower screw pump, the vertical plane on the side wall of the rotor of the lower screw pump stirs the crude oil through the rotation of the rotor of the lower screw pump, the gas in the crude oil is discharged through the first through hole under the action of centrifugal force, primary gas-liquid separation of the crude oil is realized, the crude oil after the primary gas-liquid separation is lifted into the upper screw pump under the action of the rotor and the stator of the lower screw pump, and at the moment, the gas-oil ratio of the crude oil is greatly reduced. The crude oil after the primary gas-liquid separation enters a second tail pipe of the upper screw pump, the vertical plane on the side wall of the upper screw pump rotor stirs the crude oil through the rotation of the upper screw pump rotor, and gas in the crude oil is discharged through the second through hole under the action of centrifugal force, so that the secondary gas-liquid separation of the crude oil is realized. The gas content in the crude oil subjected to the two-stage gas-liquid separation is little or none, at the moment, the crude oil subjected to the two-stage gas-liquid separation just meets the small discharge capacity requirement of the upper screw pump, and the crude oil is continuously lifted into an oil pipe under the action of a rotor and a stator of the upper screw pump. In an oil extraction system, the screw pump group is used for stirring the crude oil with high gas content, so that two-stage gas-liquid separation of the crude oil is realized, and gas in the crude oil can be reduced or removed, thereby obtaining the crude oil with low gas content or no gas.

In another technical scheme, the two vertical planes 9 of the side wall of the lower end of the rotor 5 of the lower screw pump, which is positioned at the position of the first tail pipe 7, are parallel to each other. In the first-stage gas-liquid separation, the two vertical planes parallel to each other on the rotor of the lower screw pump can effectively improve the stirring effect of the lower screw pump on the high-gas-content crude oil.

In another technical scheme, two vertical planes 9 of the side wall of the lower end of the rotor 5 of the lower screw pump, which is positioned at the position of the first tail pipe 7, are parallel to each other; the lower end of the rotor 1 of the upper screw pump is positioned on two vertical planes 11 of the side wall of the second tail pipe 3, and the two vertical planes are parallel to each other. In the first-stage gas-liquid separation, two vertical planes which are parallel to each other on the rotor of the lower screw pump can improve the stirring effect of the lower screw pump on the high gas-containing crude oil; in the secondary gas-liquid separation, two vertical planes parallel to each other on the rotor of the upper screw pump can improve the stirring effect of the upper screw pump on crude oil; thereby improving the effect of two-stage gas-liquid separation to a great extent.

In another technical scheme, the first through holes 10 are round holes, the plurality of first through holes 10 are arranged in multiple rows along the circumferential direction of the first tail pipe 7, the radian of an arc line formed between two adjacent first through holes 10 on the same circumference is 36-60 degrees, and the vertical distance between two adjacent first through holes 10 on the same row is more than 3 times the aperture of the first through holes 10. In the primary gas-liquid separation, a plurality of first through holes distributed on the first tail pipe can increase the discharge amount of gas in the crude oil while preventing the liquid in the high gas content crude oil from flowing out.

In another technical scheme, the first through holes 10 are round holes, a plurality of first through holes 10 are arranged in multiple rows along the circumferential direction of the first tail pipe 7, the radian of an arc line formed between two adjacent first through holes 10 on the same circumference is 36-60 °, and the vertical distance between two adjacent first through holes 10 on the same row is more than 3 times the aperture of the first through holes 10; the second through holes 12 are round holes, the second through holes 12 are arranged in multiple rows along the circumferential direction of the second tail pipe 3, the radian of an arc line formed between every two adjacent second through holes 12 on the same circumference is 36-60 degrees, and the vertical distance between every two adjacent second through holes 12 on the same row is more than 3 times the aperture of each second through hole 12. In the primary gas-liquid separation, a plurality of first through holes distributed on the first tail pipe can increase the discharge amount of gas in the crude oil while preventing the liquid in the high gas content crude oil from flowing out; in the secondary gas-liquid separation, a plurality of second through holes distributed on the second tail pipe can increase the discharge amount of gas in the crude oil while the liquid in the crude oil does not flow out; therefore, the gas discharge amount in the crude oil can be increased to the maximum extent while the liquid in the crude oil is prevented from flowing out, and the gas in the crude oil can be reduced or removed.

In another technical scheme, the bottom of the first tail pipe 7 is provided with a limit pin 8, the middle part of the limit pin 8 is provided with an oil flow hole, and the aperture of the oil flow hole is smaller than the size of the bottom surface of the rotor 5 of the lower screw pump. High gassy crude oil gets into in the first tail pipe in passing through the oil flow hole of spacer pin, simultaneously, when the rotor of screw pump package or the sucker rod among the oil recovery system broke, the spacer pin can bear cracked rotor or sucker rod, prevents it to drop the shaft bottom, plays the effect of protection.

In another kind of technical scheme, the bottom of first tail pipe 7 is equipped with spacer pin 8, leak hopper-shaped round hole 13 has been seted up at spacer pin 8 middle part, leak hopper-shaped round hole 13's upper shed's aperture is greater than leak hopper-shaped round hole 13's under shed's aperture, spacer pin 8 is located leak hopper-shaped round hole 13's both sides are seted up a pair of transverse section and are semicircular hole 14, and a pair of transverse section is not communicated between semicircular hole 14, leak hopper-shaped round hole 13's under shed's aperture is less than the size of the bottom surface of rotor 5 of screw pump down. The high gas-containing oil enters the first tail pipe of the lower screw pump through a pair of holes with semicircular cross sections on the limiting pin, if the crude oil contains sand, the sand is heavier than the crude oil, and in the process of stirring the crude oil by a vertical plane on the side wall of the rotor of the lower screw pump, the sand is settled at the central position and is discharged out of the tail pipe from a funnel-shaped round hole in the middle of the limiting pin under the action of centrifugal force, so that the sand prevention effect is achieved. Simultaneously, when the rotor of screw pump package or the sucker rod among the oil recovery system broke, the spacer pin can bear cracked rotor or sucker rod, prevents it and drops the shaft bottom, plays the effect of protection.

In another technical scheme, the bottom end of the second tail pipe 3 is connected with the top end of the stator 6 of the lower screw pump in a threaded manner. The upper screw pump and the lower screw pump are in threaded connection, so that the screw pump set can be conveniently disassembled and assembled.

In another technical scheme, the two ends of the flexible shaft 4 are in threaded connection with the top end of the rotor 5 of the lower screw pump and the bottom end of the rotor 1 of the upper screw pump. The flexible shaft is connected with the rotor of the upper screw pump and the rotor of the lower screw pump by threads, so that the flexible shaft can be conveniently disassembled and assembled.

While embodiments of the invention have been described above, it is not limited to the applications set forth in the description and the embodiments, which are fully applicable in various fields of endeavor to which the invention pertains, and further modifications may readily be made by those skilled in the art, it being understood that the invention is not limited to the details shown and described herein without departing from the general concept defined by the appended claims and their equivalents.