CN118815418A - Downhole driven single acting vane pump - Google Patents

Abstract

The present invention provides a downhole driven single-acting vane pump, comprising a driving mechanism, which comprises a driving member, and a packer sleeved outside the driving member and sealedly connected to the inner peripheral surface of a pipe column, and a drainage mechanism, which comprises a drainage assembly arranged downstream of the driving member, the drainage assembly comprising a liquid outlet, wherein the drainage assembly is configured to be able to cause the fluid in the pipe column to flow to the outside through the liquid outlet and the packer in sequence in a downhole driving manner under the action of the driving member. The present invention can solve the problem of rod column fatigue fracture caused by the rotation and stretching of the rod column in conventional vane pumps, and has good installation and disassembly capabilities compared to the prior art.

Description

Downhole driven single acting vane pump

Technical Field

The invention relates to the field of heavy oil reservoir production and development, and in particular to a downhole driven single-acting vane pump.

Background Art

For conventional oil reservoir development, conventional artificial lifting methods suitable for oil well lifting mainly include: rod pump oil production method, submersible electric pump oil production method, hydraulic piston pump oil production method, hydraulic jet pump oil production method, gas lift oil production method, etc. However, for heavy oil wells, especially after heavy oil thermal recovery (such as heavy oil steam injection), the above conventional lifting methods will have different degrees of adaptability problems.

In response to the above mentioned problems encountered in the development of heavy oil reservoirs, a single-acting variable displacement vane pump commonly used on the ground has become a good candidate for a new underground lifting process due to its all-metal structure and the high efficiency characteristics commonly found in positive displacement pumps. This pump is widely used in ground gathering and transportation pipelines, transportation, medical and machinery manufacturing industries.

Over the years, a number of domestic engineering and technical personnel have digested and absorbed the relevant technologies of ground vane pumps, combined with scientific research, tool development, field tests, etc., and redesigned the relevant liquid flow channels to form a new type of underground single-acting vane pump suitable for narrow underground spaces and high temperature and high pressure conditions.

However, with the continuous application of the pump on site, the immersion depth of the vane pump is greatly limited because the drive shaft is ground-driven. Therefore, the current vane pump drive system needs to be redesigned to meet the current urgent demand for deeper and deeper immersion depths.

CN206477989U discloses a double-acting vane pump for oil well production and lifting. It includes a main shaft, a pump body, an upper cam, a rotor, a stator, a lower cam and vanes, wherein the main shaft is installed in the pump body through an upper bearing component and a lower bearing component, the stator is fixedly connected to the pump body, the rotor is sleeved on the main shaft, and an annular gap is formed between the rotor and the stator, and a low-pressure oil suction area and a high-pressure oil discharge area are arranged on both sides of the annular gap, a plurality of vane grooves are arranged on the outer circumference of the rotor, and a vane is inserted in each vane groove, and the bottom of each vane groove is connected to the liquid outlet arranged on the upper bearing component, the upper cam and the lower cam are sleeved on the main shaft, and are respectively fixedly connected to the upper bearing component and the lower bearing component; each vane is pushed by the upper cam and the lower cam or the high-pressure oil entering the bottom of the vane groove to abut against the inner wall of the stator. Although the device can realize the basic functions of the vane pump, it cannot dive into a deeper well.

CN106703771A discloses a lifting device for a vane pump for oil well production. The device comprises a single plate anchor, a pump centralizer, a sand vortexer, a vane pump, a sand settling device, a spline transmission cylinder assembly, a high temperature gas injection valve, a sucker rod, an oil pipe, a well casing, an oil tree, a drive head and a bare rod, wherein the well casing is arranged below the ground surface, and the well casing is provided with a single plate anchor, a pump centralizer, a sand vortexer, a vane pump, a sand settling device, a spline transmission cylinder assembly, a high temperature gas injection valve and an oil pipe connected in sequence from bottom to top, the sucker rod is inserted into the oil pipe, and the lower end is connected to the high temperature gas injection valve, the oil tree is located above the ground surface, the bare rod is inserted into the oil tree, and is connected to the upper end of the sucker rod, and the bare rod is connected to the drive head and can be rotated by the drive head. The device is suitable for thermal production of thin oil, thick oil and high condensation oil, and does not gas lock in high temperature and gas-containing wells. For sand-containing wells, there is a sand vortex filter under the pump, and the application range is wide. Although this device can realize the basic functions of a vane pump, it cannot dive into deeper wells.

It can be seen that the existing lifting processes for vane pumps in heavy oil steam injection wells all have adaptability problems due to the influence of the driving mode, and there is still no corresponding solution in the prior art.

At present, it is hoped in the art to provide a downhole driven single-acting vane pump to solve the above technical problems.

Summary of the invention

The purpose of the present invention is to provide a downhole driven single-acting vane pump, which can replace the rod column through the separation structure of the downhole low-speed submersible motor and the downhole cable, thereby solving the rod column fatigue fracture problem caused by the rotation and stretching of the rod column in conventional vane pumps.

According to the present invention, a downhole driven single-acting vane pump is provided, comprising a driving mechanism, which comprises a driving member, and a packer sleeved outside the driving member and sealingly connected to the inner peripheral surface of a pipe string, and

The liquid discharge mechanism comprises a liquid discharge component arranged downstream of the driving member, wherein the liquid discharge component comprises a liquid outlet,

Wherein, the fluid discharge assembly is configured to be able to drive the fluid in the pipe string to flow to the outside through the fluid outlet and the packer in sequence in a downhole driving manner under the action of the driving member.

In one embodiment, the driving element is a downhole low-speed submersible motor, and is connected to the outside through a downhole cable.

In one embodiment, the liquid discharge assembly further includes a drive shaft fixedly connected to the drive member, and a vane pump sleeved outside the drive shaft, wherein the liquid outlet is radially arranged on the vane pump.

In one embodiment, the downhole driving method is to use the downhole low-speed submersible motor to drive the drive shaft to rotate, so as to cause the vane pump to discharge fluid upstream.

In one embodiment, the length of the downhole low-speed submersible motor is between 4 and 6 m, and the length of the downhole low-speed submersible motor accounts for one third to one half of the length of the drive shaft.

In one embodiment, the packer is configured as an annular structure, and a plurality of spaced-apart through holes for guiding the fluid are provided along the circumference of the annular structure.

In one embodiment, an annular groove extending radially outward is formed on the inner wall of the pipe string, and the packer is configured to be embedded in the annular groove to form a sealed connection.

In one embodiment, the downhole driven single-acting vane pump further comprises an interface converter arranged between the driving member and the driving shaft.

In one embodiment, the liquid discharge mechanism further includes a centralizer which is sleeved outside the vane pump and is sealingly connected to the inner circumferential surface of the pipe column.

In one embodiment, the vane pump is a downhole multi-stage vane pump.

Compared with the prior art, the advantages of the present invention are:

First, the present invention can replace the rod column through the separation structure of the downhole low-speed submersible motor and the downhole cable, thereby solving the rod column fatigue fracture problem caused by the rotation and stretching of the rod column of the conventional vane pump.

Secondly, in the same pipe string, the downhole driven single-acting vane pump of the present invention can deliver more fluid in the same time, thereby increasing its delivery volume per unit time.

Thirdly, compared with the prior art, the present invention has good installation and disassembly capabilities, so that the downhole driven single-acting vane pump can be put into downhole work more quickly, thereby effectively improving work efficiency.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will be described in detail below in conjunction with the accompanying drawings, in which:

FIG1 schematically shows the structure of a downhole driven single-acting vane pump according to the present invention;

2 is a cross-sectional view of a packer in a downhole driven single-acting vane pump according to the present invention.

In the drawings, the same reference numerals are used for the same components. The drawings are not drawn to scale.

The meanings of the reference numerals in the accompanying drawings are as follows:

11 driving member, 12 packer, 121 through hole,

21 Centralizer,

3 drainage assembly, drive shaft, 32 vane pump, 321 liquid outlet,

4 interface converters,

101 pipe string, 102 downhole cable.

DETAILED DESCRIPTION

In order to make the technical solutions and advantages of the present invention more clearly understood, the exemplary embodiments of the present invention are further described in detail below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than an exhaustive list of all the embodiments. In addition, the embodiments of the present invention and the features in the embodiments can be combined with each other without conflict.

It is easy to understand that the directional terms "upstream" or "above" or similar terms refer to the direction close to the wellhead, that is, the top direction in Figure 1. The directional terms "downstream" or "below" or similar terms refer to the direction away from the wellhead, that is, the bottom direction in Figure 1.

The present invention will be further described below in conjunction with the accompanying drawings.

FIG. 1 schematically shows the structure of a downhole driven single-acting vane pump 100 according to the present invention.

As shown in FIG1 , a downhole driven single-acting vane pump 100 according to the present invention includes a driving mechanism. The driving mechanism includes a driving member 11 and a packer 12. The driving member 11 is installed in a pipe string 101 through a downhole cable 102. The packer 12 is sleeved outside the driving member 11, and the packer 12 can be sealed and connected to the inner circumferential surface of the pipe string 101.

In a preferred embodiment, as shown in FIG1 , the packer 12 is configured to allow the fluid in the tubular string 101 to flow to the outside only through the through hole 121 (described below) thereon, so as to ensure that the driving member 11 has good working performance in the tubular string 101 .

According to the present invention, the downhole driven single-acting vane pump 100 further comprises a liquid discharge mechanism. As shown in FIG1 , the liquid discharge mechanism comprises a liquid discharge assembly 3 disposed downstream of the driving member 11. Preferably, the liquid discharge assembly 3 comprises a liquid outlet 321 for guiding the fluid in the tubing string 101.

According to one embodiment of the present invention, the drainage assembly 3 is configured to enable the fluid in the tubing string 101 to flow to the outside through the fluid outlet 321 and the through hole 121 on the packer 12 in a downhole driving manner (described below) under the action of the driving member 11.

In a specific embodiment, as shown in FIG1 , the driving member 11 is a downhole low-speed submersible motor, and the downhole low-speed submersible motor is connected to the outside through a downhole cable 102. In this way, on the one hand, the downhole driven single-acting vane pump 100 can be more easily lowered into the pipe string 101 to smoothly carry out subsequent work; on the other hand, since the overall volume of the downhole low-speed submersible motor is small, it can be more easily installed and disassembled.

According to one embodiment of the present invention, the downhole driving method refers to driving the driving shaft (introduced below) to rotate by a downhole low-speed submersible motor (referring to the driving member 11), thereby prompting the vane pump 32 (introduced below) to discharge fluid upstream.

At present, the conventional ground drive in the prior art usually uses a long rod to drive the vane pump to extract fluid underground. Since the rod is long overall, this method easily leads to fatigue fracture of the rod during rotation and stretching, which seriously affects the normal construction work underground.

Compared with the above-mentioned prior art, the present invention adopts the downhole driving method as described above, replacing the rod column by a downhole low-speed submersible motor and a downhole cable 102 connected to the downhole low-speed submersible motor, thereby realizing the driving work of the vane pump 32 (introduced below).

In this way, on the one hand, the problem of fatigue fracture of the rod column caused by the traditional ground drive during rotation and stretching can be effectively solved, thereby ensuring the safety of underground construction and improving the construction efficiency. On the other hand, since the length of the underground cable 102 is controllable, the underground drive single-acting vane pump 100 of the present invention can more easily adapt to deeper well depths, thus achieving good versatility.

In addition, the downhole low-speed submersible motor has a shorter length than the rod string, and the downhole low-speed submersible motor is smaller in size.

Preferably, on the one hand, using a downhole low-speed submersible motor in the same tubing string 101 can deliver more fluid in the same time, thereby increasing the delivery volume of the downhole driven single-acting vane pump 100 per unit time; on the other hand, the downhole low-speed submersible motor has good installation and disassembly capabilities compared to the rod string, thereby enabling the downhole driven single-acting vane pump 100 to be put into downhole work more quickly, thereby effectively improving work efficiency.

According to the present invention, the liquid discharge assembly 3 further includes a drive shaft (not shown in the drawings) and a vane pump 32. As shown in FIG1 , the drive member 11 is fixedly connected to the drive shaft 11, so that the drive shaft can be driven to rotate more easily. The vane pump 32 is sleeved outside the drive shaft and can rotate synchronously with the drive shaft, so that the downhole extraction work can be carried out smoothly.

In a preferred embodiment, the liquid outlet 321 is radially arranged on the vane pump 32. In this way, the liquid in the wellbore 101 extracted by the vane pump 32 can be discharged more quickly and more completely through the liquid outlet 321, and further moves upstream along the pipe string 101 through the packer 12, thereby achieving the purpose of liquid discharge.

It is easy to understand that the fluid in the wellbore 101 can be quickly discharged to the surroundings through the liquid outlet 321. Since the through holes 121 of the packer 12 are all located around the driving member 11, the fluid passing through the liquid outlet 321 can pass through the through holes 121 at a faster speed and move upstream along the pipe string 101, thereby achieving the purpose of rapid liquid discharge.

In a specific embodiment, the length of the downhole low-speed submersible motor (referring to the driving member 11) is 4 to 6 meters. It is easy to understand that since the rod string in the prior art needs to be extended into the well for driving, its length is usually dozens or even hundreds of times that of the motor (driving member 11).

It can be seen that the driving member 11 in the present invention has an extremely small volume compared to the rod column in the technology, so that it can have better stability, adaptability and safety during underground work, thereby increasing the service life of the driving member 11 underground, and further improving the stability and safety of the underground driven single-acting vane pump 100 working underground.

In one embodiment, the length of the downhole low-speed submersible motor (referring to the driving member 11) accounts for one third to one half of the length of the driving shaft. Since the driving member 11 and the driving shaft are fixedly connected, the two can move synchronously, thereby ensuring the stability of the driving member 11 and the driving shaft during operation, thereby effectively avoiding fatigue fracture of the driving shaft during rotation and stretching, thereby ensuring the safety of the driving shaft and the driving member 11 working underground.

In one embodiment, the packer 12 is configured as an annular structure, thereby facilitating a sealed connection between the driver 11 and the tubing string 101. In this way, the fluid in the tubing string 101 can only flow to the outside through the through hole 121 provided on the packer 12.

In one embodiment, a plurality of spaced through holes 121 for guiding fluid are arranged along the circumference of the annular structure (referring to the packer 12). As shown in FIG2 , specifically, adjacent through holes 121 are equally spaced. In this way, the fluid passing through the liquid outlet 321 can more accurately pass through the through holes 121 and move upstream along the pipe string 101, thereby achieving the purpose of rapid liquid discharge.

In another embodiment, a plurality of spaced through grooves (not shown) for guiding fluid are arranged along the circumference of the annular structure (referring to the packer 12). Specifically, adjacent through grooves are equally spaced. In this way, the fluid passing through the liquid outlet 321 can pass through the through grooves faster and move upstream along the pipe string 101, thereby achieving the purpose of rapid liquid discharge.

In one embodiment, an annular groove (not shown) extending radially outward is formed on the inner wall of the tubular column 101. The packer 12 is configured to be embedded in the annular groove to form a sealed connection. Since the packer 12 is fixedly connected to the driver 11 to play a supporting role. Therefore, by embedding the packer 12 in the annular groove, its support capacity for the driver 11 can be significantly improved, thereby ensuring that the driver 11 can always have a stable working environment in the tubular column 101.

According to the present invention, as shown in Fig. 1, the downhole driven single-acting vane pump 100 further includes an interface converter 4. The interface converter is arranged between the driving member 11 and the driving shaft, and can fixedly connect the two, thereby ensuring that the driving shaft and the vane pump 32 can smoothly rotate synchronously, thereby achieving the purpose of rapid liquid discharge.

According to the present invention, as shown in Fig. 1, the downhole driven single-acting vane pump 100 further includes a centralizer 21. The centralizer 21 is sleeved outside the vane pump 32 and can form a sealed connection relationship with the inner circumferential surface of the pipe string 101, thereby ensuring that the vane pump 32 can always have a stable working environment in the pipe string 101, thereby achieving the purpose of rapid liquid discharge.

Preferably, since the driving member 11 can be indirectly connected to the vane pump 32 via the driving shaft, the packer 12 and the centralizer 21 can jointly assume the supporting role for the downhole driven single-acting vane pump 100 .

In a preferred embodiment, the vane pump 32 is a downhole multi-stage vane pump.

Compared with the prior art, the present invention improves the conventional driving method of the vane pump, thereby driving the vane pump 32 by downhole driving. Specifically, the vane pump 32 is driven by the split structure of the downhole submersible low-speed motor (referring to the driving member 11) and the downhole cable 102, thereby being able to more easily and effectively solve the rod column fatigue fracture problem caused by the rotation and stretching of the rod column in the conventional vane pump.

Compared with the prior art, the present invention has the following advantages.

First, the present invention can replace the rod column by separating the downhole low-speed submersible motor (driving element 11) and the downhole cable 102, thereby solving the rod column fatigue fracture problem caused by the rotation and stretching of the rod column in conventional vane pumps.

Secondly, in the same pipe string 101, the downhole driven single-acting vane pump 100 of the present invention can deliver more fluid in the same time, thereby increasing its delivery volume per unit time.

Thirdly, compared with the prior art, the present invention has good installation and disassembly capabilities, so that the downhole driven single-acting vane pump 100 can be put into downhole work more quickly, thereby effectively improving work efficiency.

The present invention provides a downhole driven single-acting vane pump 100, which can replace the rod column through the separation structure of the downhole low-speed submersible motor and the downhole cable 102, thereby solving the problem of fatigue fracture of the rod column caused by the rotation and stretching of the rod column of the conventional vane pump. In addition, in the same pipe column 101, the present invention can transport more fluid in the same time, thereby increasing the delivery volume of the downhole driven single-acting vane pump 100 per unit time. In addition, compared with the prior art, the present invention has good installation and disassembly capabilities, thereby enabling the downhole driven single-acting vane pump 100 to be put into downhole work more quickly, thereby effectively improving work efficiency.

In the description of the present invention, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features.

In the present invention, unless otherwise clearly stipulated and limited, terms such as "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be the internal connection of two elements.

For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

The above are only preferred embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art can easily make changes or modifications within the disclosure scope of the present invention, and such changes or modifications should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims (10)

1. A downhole driven single action vane pump comprising:

a driving mechanism comprising a driving member (11), and a packer (12) sleeved outside the driving member (11) and connected with the inner peripheral surface of the pipe column (101) in a sealing manner, and

A liquid discharge mechanism comprising a liquid discharge assembly (3) arranged at the downstream of the driving member (11), wherein the liquid discharge assembly (3) comprises a liquid outlet (321),

Wherein the drainage assembly (3) is configured to drive fluid in the tubular string (101) to the outside through the outlet (321) and the packer (12) in sequence in a downhole driving manner under the action of the driving member (11).

2. A downhole driven single-acting vane pump according to claim 1, wherein the driving member (11) is a downhole low-speed submersible motor and communicates with the outside via a downhole cable (102).

3. A downhole driven single action vane pump according to claim 2, wherein the drainage assembly (3) further comprises a drive shaft fixedly connected with the drive member (11), and a vane pump (32) sleeved outside the drive shaft, wherein the liquid outlet (321) is radially arranged on the vane pump (32).

4. A downhole driven single action vane pump according to claim 3, wherein the downhole driving is by rotation of the drive shaft by the downhole low speed submersible motor to cause the vane pump (32) to drain upstream.

5. The downhole driven single action vane pump of claim 4 wherein the length of the downhole low speed submersible motor is between 4 and 6m and the length of the downhole low speed submersible motor is between one third and one half the length of the drive shaft.

6. A downhole driven single action vane pump according to claim 5, wherein the packer (12) is configured as an annular structure and a number of spaced apart through holes (121) for guiding the fluid are provided along the circumference of the annular structure.

7. A downhole driven single action vane pump according to claim 6, wherein a radially outwardly extending annular groove is formed on an inner wall of the tubular string (101), the packer (12) being configured to be inserted into the annular groove to form a sealed connection.

8. A downhole driven single action vane pump according to claim 7, further comprising an interface converter (4) arranged between the drive (11) and the drive shaft.

9. A downhole driven single action vane pump according to claim 8, wherein the drainage mechanism further comprises a centralizer (21) sleeved outside the vane pump (32) and sealingly connected to the inner peripheral surface of the pipe string (101).

10. A downhole driven single action vane pump according to any of claims 3-9, wherein the vane pump (32) is a downhole multi-stage vane pump.