WO2013026256A1

WO2013026256A1 - Downhole pressurization device

Info

Publication number: WO2013026256A1
Application number: PCT/CN2012/000834
Authority: WO
Inventors: 于连杰; 张松峰; 汪恩宝; 武强; 张�林; 魏向辉
Original assignee: 中国石油天然气集团公司; 中国石油集团渤海石油装备制造有限公司; 渤海石油装备（天津）中成机械制造有限公司
Priority date: 2011-08-19
Filing date: 2012-06-15
Publication date: 2013-02-28
Also published as: CN102953696A

Abstract

A downhole pressurization device comprises a sleeve (7) and a drill tube-shaped column (4). A pressurization tube-shaped column (10) is disposed between the sleeve (7) and the drill tube-shaped column (4). An annular space exists between the inner hole of the pressurization tube-shaped column (10) and the outer circumference of the drill tube-shaped column (4). An annular space exists between the outer circumference of the pressurization tube-shaped column (10) and the inner hole of the sleeve (7). An upper pressurization sleeve, a chamber (1), and a lower pressurization sleeve of the pressurization tube-shaped column (10) are fixedly connected sequentially from top to bottom. An annular packer (9) for packing the annular space of the pressurization tube-shaped column (10) and the sleeve (7) is mounted on the lower pressurization sleeve below the chamber (1). A pressurization water hole (2) is fixedly mounted on the chamber (1). The pressurization water hole (2) is in communication with an annular space outside the chamber (1). The pressurization device is simple in structure, and can increase the circulation rate of the downhole liquid without changing the rated pressure of the ground pump-pressurization system, thereby improving performance of rock breaking and sand-carrying.

Description

Downhole booster

Technical field

The invention relates to a device for improving the circulation speed of a downhole circulation in a petroleum natural gas drilling operation, in particular to a downhole supercharging device for oil drilling.

Background technique

In order to improve the drilling speed of oil and gas exploitation, the research on the drilling fluid circulation system has been strengthened. In the United States in the 1970s, tests showed that the drilling speed can be increased by 5 to 8 times when drilling on the ground using a circulation system with a high pump pressure of 105 MPa. However, due to the limitations of high-pressure jet drilling system equipment, the application range is narrow. high cost. At present, drilling fluid circulation system for drilling is applied under special well conditions such as high-angle wells and horizontal wells, and the ability to break rock and carry sand is reduced, thus affecting drilling efficiency. For example: When the pump pressure is 18~20MPa and the displacement is 28~32L/s, when the drilling depth reaches 3000m, the circulation pressure is only 9~12MPa _; when the well depth reaches 6000m, the pressure is basically exhausted along the path. . Therefore, the deeper the well, the smaller the pressure drop of the bottom hole, the lower the ability of the drilling fluid to wash and sand the bottom of the well, and greatly reduce the drilling efficiency.

In order to improve drilling efficiency, most of the booster pumps are installed underground. The Downhole Supercharger (Patent No. 94103752.5) is a volumetric multi-cylinder hydraulic supercharger driven by a mechanical reversing mechanism, which adopts a gear-driven reversing mechanism. The structure is complex, the manufacturing is difficult, and the cost is large. China utility model patent "an oil drilling downhole turbocharger" (patent number 01216627.8), installed between the bottom hole power drill and the drill bit, it can improve the bottom hole liquid pressure without changing the ground pump pressure More than 5 times. It relies on a bottom-hole power drill to provide power, and uses a ram-type multi-cylinder hydraulic boosting design consisting of a swash plate, multiple booster cylinders, a plunger, a liquid flow path, a check valve, and a load-bearing casing. Driven by the inner rotor of the power drill, the spherical chute on the swash plate connected to it is also rotated at the same speed at a high speed, thereby driving the plunger to reciprocate in the booster cylinder to generate high-pressure liquid through the ultra-high pressure. The pipeline is discharged from the drill nozzle to achieve high pressure jet drilling to increase the drilling speed. Due to the use of plunger multi-cylinder hydraulic pressurization The structure is also complicated and the service life is short.

Summary of the invention

SUMMARY OF THE INVENTION The object of the present invention is to provide a downhole pressurizing device which overcomes the disadvantages of complicated structure, high manufacturing difficulty and high cost of the booster used in the existing oil drilling operation.

The downhole supercharging device of the present invention comprises a casing and a drill pipe string, wherein the drill pipe string is located in the casing, and a boosting pipe column is arranged between the casing and the drill pipe string, and the inner hole of the pressurized pipe column is The outer circumference of the drill pipe string is an annulus, and the outer circle of the pressurized pipe column and the inner hole of the casing are annulus. The upper pressurizing sleeve, the cavity and the lower pressurizing sleeve of the pressurized tubular column are fixedly connected from top to bottom, and a packer is installed on the lower pressurizing sleeve below the cavity for sealing the pressurized tubular string and The annular space of the casing; the pressurized water eye is fixedly mounted on the cavity, and the pressurized water eye communicates with the annulus inside and outside the cavity. The outer circle of the cavity is a stepped axis with a small middle and large end at both ends, and the upper end of the large shaft diameter is a small upper and lower cone; the inner hole of the large axial diameter of the cavity is a conical hole with a small upper and a lower; the large axis of the cavity The lower end surface of the diameter is uniformly fixedly installed with two or more pressurized water eyes, and the angle between the axis of the pressurized water eye and the axis of the cavity is ≤45°, and the upper end of the pressurized water eye and the inner cone of the cavity The same. Two or more superchargers are installed in series.

DRAWINGS

1 is a schematic view showing the structure of a downhole pressurizing device of the present invention and its working principle.

In the figure: 1. cavity, 2. pressurized water eye, 3. pressurized casing, 4. drilling pipe column, 5. drilling fluid channel, 6. inner drilling fluid channel, 7. casing, 8. Outer drilling fluid channel, 9. Packer, 10. Pressurized column.

Concrete

The invention will now be further described with reference to the accompanying drawings and embodiments.

The downhole pressurizing device of the present invention comprises a casing 7, a boosting pipe string 10, a drill pipe string 4, and is installed from the outside to the inside, and a ring is formed between the inner hole of the pressurized pipe column 10 and the outer circumference of the drill pipe string 4. Empty, supercharged pipe column 10 outer circle ^ check 昝7 ΛίΙ.τ' ΓΗΐ^τΙ^^. The upper and lower ends of the cavity 1 of the pressurized tubular column 10 are fixedly connected with a pressurized casing 3, and the lower pressurized casing below the cavity 1 is mounted with a packer 9 for sealing the pressurized column 10 and the sleeve. The annulus between the tubes 7 is empty. A pressurized water eye 2 is fixedly mounted on the cavity 1, and the pressurized water eye 2 communicates with the annulus inside and outside the cavity 1.

The outer circumference of the cavity 1 is a stepped shaft having a small intermediate portion at both ends, and the upper end portion of the large shaft diameter is a small upper and lower cone; the inner hole corresponding to the middle portion of the large shaft diameter is a tapered hole having a small upper and a lower; The conical taper angles inside and outside the cavity 1 are substantially the same. The lower end surface of the large shaft diameter of the cavity 1 is uniformly fixed to the circumference by two or more pressurized water eyes 2, and usually four pressurized water eyes 2 are installed. There should be an angle between the axis of the pressurized water eye 2 and the axis of the cavity 1 with an angle of 45° and an optimum angle of the angle of 25 to 30°. The upper end of the pressurized water eye 2 communicates with the inner tapered hole of the cavity 1. The outer surface of the cavity 1 on which the pressurized water eye 2 is installed is processed into a lug shape, which can increase the liquid flow rate of the outer circumference of the pressurized column 10 and the inner ring of the casing 7.

In order to improve the erosion resistance of the downhole pressurizing device, the surface of the cavity 1 may be reinforced.

: mk practicality

When the drilling operation of the downhole pressurizing device according to the present invention is used, the drilling fluid entering the drilling string 4 enters the annulus between the drilling string 4 and the pressurized tubular column 10 when returning through the drilling fluid passage 5. Inner drilling fluid channel 6; outer drilling fluid enters the outer drilling fluid channel 8 formed from the wellhead into the annulus between the casing and the pressurized column 10, and the seal between the casing 7 and the pressurized column Under the action of the separator 9, there is a pressure difference between the outer drilling fluid and the inner drilling fluid, and the outer drilling fluid enters the inner drilling fluid passage 6 through the water eye installed on the cavity 1, accelerating the return of the drilling fluid. , to improve the circulation speed and sand carrying capacity of the entire inner drilling fluid, to achieve the purpose of improving drilling efficiency.

When drilling with the downhole booster of the present invention, two or more superchargers can be installed in series according to the needs of the drilling operation, thereby achieving the purpose of strong pressurization.

The downhole supercharging device of the invention has the advantages of simple structure and reasonable design, can increase the circulation speed of the well T liquid and improve the rock breaking and sand carrying capacity without changing the rated pressure of the ground pumping system. Improve drilling efficiency, reduce drilling costs, and increase the use of downhole turbochargers

Life

Claims

Rights request

A downhole pressurizing device comprising a casing, a drill pipe string, and a drill pipe string located in the casing, characterized in that a pressurization is provided between the casing (7) and the drill pipe string (4) The column (10), the inner hole of the booster column (10) and the outer circumference of the drill string (4) are annulus, between the outer circumference of the pressurized column (10) and the inner hole of the casing (7) It is an air.

2. The downhole supercharging device according to claim 1, wherein: the supercharged tubular string (10) is in turn from the upper pressurized casing, the cavity (1), and the lower pressurized casing from top to bottom. Fixed connection.

3. The downhole supercharging device according to claim 2, wherein: the outer circumference of the cavity (1) is a stepped shaft having a small intermediate portion at both ends, and the upper end portion of the large shaft diameter is upper and lower. Cone.

4. The downhole supercharging device according to claim 3, wherein: the inner hole of the large axial diameter of the cavity (1) is a conical hole that is large and small.

5. The downhole pressurization device according to claim 2, characterized in that: a packer (9) is mounted on the lower pressurizing sleeve below the cavity (1) for sealing the booster column (10) The annulus with the casing (7).

6. The downhole supercharging device according to claim 2, wherein: the pressurized body eye (2) is fixedly mounted on the cavity (1), and the pressurized water eye (2) is connected to the inside and outside of the cavity (1). The ring is empty.

7. The downhole supercharging device according to claim 6, wherein: the pressurized water eye (2) is uniformly fixed on the circumference of the lower end surface of the large shaft diameter of the cavity (1).

8. The downhole boosting device according to claim 6, wherein: said pressurized water eye (2) is 2 to 4 pressurized water eyes.

9. The downhole boosting device according to claim 6, wherein: the axis of the pressurized water eye (2) is at an angle of 45 to the axis of the cavity (1).

10. The downhole supercharging device according to claim 6, wherein the angle between the axis of the pressurized water eye (2) and the axis of the cavity (1) is 2^30.

11. The downhole increasing device according to claim 6, wherein the upper end of the pressurized water suit (2) communicates with the inner tapered hole of the cavity (1).

12. The downhole supercharging device according to claim 1, wherein: two or more of the supercharging devices are installed in series.