CN106988718B

CN106988718B - Shale gas fracturing method and device

Info

Publication number: CN106988718B
Application number: CN201610037400.9A
Authority: CN
Inventors: 杨晓峰; 周家恒; 朱孟禹; 周鑫; 朱洪亮; 满诗涵
Original assignee: China University of Mining and Technology Beijing CUMTB
Current assignee: China University of Mining and Technology Beijing CUMTB
Priority date: 2016-01-20
Filing date: 2016-01-20
Publication date: 2023-12-08
Anticipated expiration: 2036-01-20
Also published as: CN106988718A

Abstract

The invention discloses a shale gas fracturing method and device, which mainly comprise an integrated control system, ground fracturing equipment, a direction control module, a directional drilling machine, a fracturing pump and a shale gas fracturing drill bit; the shale gas fracturing drill bit comprises a three-wing drill bit, a high-pressure gas guide pipe, a direction control system, an electromagnetic numerical control valve, a conductive wire, an insulating layer and a steering joint; when the device works, the three-wing drill bit and the steering system are screwed into a target position, and after the drilling machine is stopped, the fracturing direction control system transmits azimuth information to determine the fracturing direction and the specific position. The fracturing system on the ground generates ultrahigh-pressure carbon dioxide gas through a gas fracturing pump, the ultrahigh-pressure carbon dioxide gas is conveyed to the drill bit side through a high-pressure gas conduit paved inside one side of the drill rod, and then the fracturing state is controlled by an electromagnetic numerical control valve, so that the fracturing task is completed.

Description

Shale gas fracturing method and device

Technical Field

The invention relates to the technical field of shale gas fracturing, in particular to a shale gas fracturing method and device.

Background

In the current shale gas fracturing exploitation process, complex machinery such as a vertical or horizontal drilling well, a fracturing packer, a sliding sleeve, a drillable fracturing bridge plug and the like are used for being matched with each other to finish a large-area fracturing task, and a drilling fracturing exploitation method which is simple and feasible and low in cost is lacked. The existing technical conditions are more suitable for large-scale and high-investment regional exploitation, however, under the condition of insufficient first fracturing or fracturing dead angles, the existing exploitation mode is undoubtedly inexpensible, the fracturing effect is poor, more time and cost are consumed in the traditional workflow of exiting from fracturing after drilling, and the engineering progress is prolonged.

The nature of shale gas production itself dictates that the fracturing design must be limited by natural fractures and ground stress, where the fracturing locations in the design are often on the vertical planes of several main wells, and where it is difficult to achieve good fracturing results by conventional methods. There is a need for more flexible and extensive fracturing techniques without requiring excellent fracturing results or fracturing targets at specific locations that are far from the main well.

In addition, the existing hydraulic fracturing technology mostly needs large-scale fracturing equipment on the ground, the fracturing effect and the exploitation effect are far lower than those of the pneumatic fracturing technology, and the pneumatic fracturing has the advantages and good development prospect, so that the pneumatic fracturing technology is focused, and is a mainstream trend of shale gas exploitation in the future.

Therefore, the shale gas fracturing equipment with strong development applicability, low cost, flexibility and variability must be innovated from multiple angles such as simplified flow, flexible direction change and the like to the existing fracturing machinery.

Disclosure of Invention

The invention provides a shale gas fracturing method and device for solving the technical problems existing in the prior art.

The technical scheme adopted by the invention is as follows: the shale gas fracturing method and device comprises an integrated control system, ground fracturing equipment, a directional control PLC, a directional drilling machine, a fracturing pump, a shale gas fracturing drill bit and the like; the shale gas pressure drill bit mainly comprises a three-wing drill bit, an electromagnetic numerical control valve, a high-pressure gas conduit, a direction control system, an insulating layer, a junction box and a conductive wire. The three-wing drill bit and the matched steering system are screwed into a target position, and after the drilling machine is stopped, the fracturing direction control system transmits azimuth information, so that the fracturing direction and the specific position are determined. The fracturing system on the ground generates ultrahigh-pressure carbon dioxide gas through a gas fracturing pump, the ultrahigh-pressure carbon dioxide gas is conveyed to the drill bit side through a high-pressure gas conduit paved inside one side of the drill rod, and the fracturing state is controlled through an electromagnetic numerical control valve, so that the fracturing task is completed.

The invention has the advantages that:

1. the shale gas fracturing drill bit is simple in structure and integrates drilling and shale gas fracturing. The drilling work and the fracturing work are combined uniformly, the heat dissipation process of the drill bit is synchronous with the fracturing process, the working space is saved, the manpower and material resources required by a series of working procedures such as replacing the fracturing equipment after drilling in the existing method are saved, and the small-range fracturing task can be completed rapidly and efficiently.

2. The invention has simple structural characteristics, a directional drilling mode and a direction control system with high control force, an electromagnetic valve numerical control system and an integrated system for setting azimuth information on the ground in real time also enable unrestricted and different multi-directional synchronous fracturing to be possible, a drill bit is matched with a drill rod to be similar to a common drill rod, the depth can be easily increased, the drilling direction can be flexibly changed, and therefore, the effective fracturing range is enlarged, and the target position is directionally fractured at fixed points.

3. The shale gas fracturing method and device have extremely strong applicability, can be used for solving the problem that the exploitation of the shale gas in a small range is incomplete or is irresistible, and can finish the gas fracturing work with low cost. According to the method for lateral laminating fracturing and fracturing after screwing in of the drill bit, the drill bit is screwed in to the fracturing position, the fracturing direction is determined by the fracturing direction control system at the top end of the drill bit and is subjected to fine adjustment, an instruction is sent to open an electromagnetic numerical control valve to be communicated with an external pneumatic fracturing pump, a shale gas fracturing task is completed, and the method is simple and easy to implement and is convenient to control.

Drawings

FIG. 1 is a system diagram of the present invention;

fig. 2 is an enlarged side and longitudinal cross-sectional view of a shale gas fracturing bit of the present invention.

In fig. 2: the three-wing drill bit is characterized in that the three-wing drill bit is 1, the high-pressure gas guide pipe is 2, the directional control system integrator is 3, the electromagnetic numerical control valve is 4, the conductive wire and the insulating layer are 5, the drill rod part connected with the drill bit is 6, and the steering joint is 7.

Detailed Description

The technical scheme of the invention is further specifically described below with reference to the accompanying drawings.

A shale gas fracturing method and device mainly comprises an integrated control system, ground fracturing equipment, a directional control PLC, a directional drilling machine, a fracturing pump, a shale gas fracturing drill bit and the like; the equipment and the system are mutually communicated, and information and instructions are issued by taking the integrated control system and the directional control PLC as cores.

The shale gas fracturing drill bit mainly comprises a three-wing drill bit 1, a high-pressure gas guide pipe 2, a direction control system 3, an electromagnetic numerical control valve 4, a conductive wire 5, an insulating layer, a drill rod part 6 connected with the drill bit and a steering joint 7; the high-pressure gas conduit 2 keeps safe wall thickness, a side opening on the drill bit 1 is communicated with the rock wall through a T-shaped opening, the drill bit is attached to the rock wall through expansion with heat and contraction with cold after drilling is completed, and the integrated device of the direction control system 3 and the electromagnetic numerical control valve 4 on the drill bit 1 is communicated with the outside through a wire and the insulating layer 5 thereof and participates in main movement of the rotation of the drill bit.

The shale gas fracturing method and device disclosed by the invention have the following working processes:

the method comprises the steps of estimating and connecting a certain number of drill pipes 6 with high-pressure gas conduits in a matching way through measurement and calculation, screwing the drill pipes to a designated fracturing position to stop, confirming the position of an opening of a lateral conduit and the longitudinal and transverse deflection angle through a direction control system 3 of a built-in gyroscope, performing fine adjustment, controlling an electromagnetic numerical control valve 4 on the outer side of a three-wing drill bit 1 through ground to open, and communicating an air fracturing pump device on the ground and a rock wall attached to the side of the drill bit behind the drill pipes through the high-pressure gas conduits 2 to complete air fracturing.

The foregoing description of the preferred embodiment of the invention is not intended to be limiting, but rather, the invention is capable of numerous variations and modifications without departing from the spirit and scope of the invention. The scope of the invention is defined by the appended claims and equivalents.

Claims

1. The shale gas fracturing device comprises an integrated control system, ground fracturing equipment, a directional control PLC, a directional drilling machine, a fracturing pump and a shale gas fracturing drill bit; the shale gas fracturing drill bit consists of a three-wing drill bit (1), a high-pressure gas guide pipe (2), a direction control system (3), an electromagnetic numerical control valve (4), a conducting wire (5), an insulating layer, a drill rod part (6) connected with the drill bit and a steering joint (7); shale gas fracturing device, its characterized in that:

(a) The direction control system (3) is internally provided with a gyroscope to determine the position of the three-wing drill bit (1); screwing the three-wing drill bit (1) to a fracturing position, determining the fracturing direction and performing fine adjustment by the direction control system (3) based on the actual drilling position of the drill bit, then sending out an instruction to open an electromagnetic numerical control valve (4) to communicate an external pneumatic fracturing pump, and flushing high-pressure gas to complete a shale pneumatic fracturing task;

(b) The electromagnetic numerical control valve (4) is connected with a fracturing pump and a drilling machine on the ground through a cavity and a wire hole on the cavity by a conductive wire (5) so as to execute a valve opening and closing instruction;

(c) The direction control system (3) is connected with the direction control system on the ground through the cavity and the wire guide hole on the cavity by the conductive wire (5) so as to transmit position information;

(d) The high-pressure gas guide pipe (2) is arranged on one side of the inside of the three-wing drill bit (1), internal high-pressure gas is generated by ground fracturing equipment, is sent to the top end of the drill bit through the high-pressure gas guide pipe (2) in the shale gas fracturing drill bit, is controlled to be released by the electromagnetic numerical control valve (4) after drilling is completed, is communicated with the outside under the condition that the head is controlled by the electromagnetic numerical control valve (4), and the pressure of the gas passing through the high-pressure gas guide pipe (2) is 10-100MPa, and is high-pressure carbon dioxide.

2. The shale gas fracturing device according to claim 1, wherein the integrated control system, the ground fracturing equipment, the directional control PLC and the directional drilling machine are communicated with each other, and the integrated control system and the directional control PLC are used as cores for issuing information and instructions.