CN116201471A - Repeatedly usable's fishbone formula multi-branch drilling system - Google Patents

Abstract

The invention discloses a reusable fishbone type multi-branch drilling system which comprises a drilling assembly support bracket body, an outer cylinder assembly, a connecting body, a hydraulic reciprocating push-pull rod, a plurality of drill bits, a plurality of flexible pipes and a plurality of driving turbines, wherein the drilling assembly support bracket body is internally provided with a plurality of drill bit channels, each drill bit is connected with the corresponding flexible pipe, the flexible pipes are connected to the driving turbines, the driving turbines are all positioned in the outer cylinder assembly, one end of the outer cylinder assembly is in sealing connection with the drilling assembly support bracket body, the other end of the outer cylinder assembly is in sealing connection with the connecting body, a flexible connecting shaft is arranged in the connecting body, and the hydraulic reciprocating push-pull rod is connected with each driving turbine through the flexible connecting shaft. The system well solves the problem that the flexible pipe cannot be reused after the hole is drilled, realizes repeated use of a single tool, and has the advantages of simple installation, light weight, proper length and no use limitation.

Description

A reusable fishbone spur type multi-branch drilling system

technical field

The invention relates to an oil and gas field stimulation downhole tool, in particular to a reusable fishbone spur type multi-branch drilling system.

Background technique

Fishbone drilling technology has developed a new way of connecting oil and gas reservoirs with high efficiency, precision and controllability. Fishbone branch wells use one main wellbore to drill A technology based on well completion methods can effectively improve the connectivity between oil and gas wells and reservoirs, expand the drainage area of a single well, and is an effective means to increase the productivity of a single well. At present, most domestic oil and gas wells still use cementing, perforation and screen completion in the completion stage, and the initial or later production is not ideal, and the application of fracturing stimulation technology and fishbone branch well technology is blank .

Oil field completion hydraulic fracturing operations will cause groundwater pollution. During the fracturing process, the fracturing fluid containing a large amount of chemical additives is injected into the ground, and the formation is fractured under high pressure. Therefore, the fracturing fluid will pollute the groundwater body, and the oil and gas reservoir rock After fracturing, oil and gas may also escape into the groundwater layer, causing pollution to groundwater, and the cost of hydraulic fracturing is huge. However, in the fields of tight limestone, tight sandstone and coalbed methane in the United States, Norway and other countries, fishbone drilling technology has been applied, with an average increase of 2 to 8 times, and the effect is good. The applied equipment is lowered to the designated position with the expansion setter , after setting, under the action of hydraulic pressure, the turbine drives the needle drill bit to rotate, and the three branches drill into the formation to realize the connection between the branch pipeline and the main pipeline, but this equipment is for one-time use, and the total length of the flexible pipe inserted Longer, it is not suitable for the well type where the setting body is difficult to run in, and the tool cannot be recycled, resulting in higher cost per well.

Although technical means such as fracturing and stimulation can also achieve the effect of production stimulation, there are high costs, completion of long horizontal section, liner cementing of large section of horizontal section, separate completion of open hole intervals, large differences in hydraulic fracturing results, and differences with production layers. Uncontrollable and unmeasurable connectivity, water flooding, single-layer coning of water injection and other shortcomings, and also pollute the environment. Since its application, the fishbone drilling technology has good production stimulation effect, and the production stimulation effect of anisotropic or faulted reservoirs is good; the construction is simple and reliable, and there is no casing, cementing, perforation and fracturing; the construction period is short, the cost is low, and the economic performance is high. Less, workover rig operation cost can be canceled; HSE risk is low, especially to avoid low qualified rate of horizontal well cementing; less operation time, mainly by reducing the operation time to save operation time; less liquid volume required, higher production than under the same conditions The amount of liquid required for the operation is less; the required high pump pressure equipment is less than the number of pumps and tanks used for fracturing and acid fracturing; Layer section requirements, according to the needs of stratum stratification, the labor intensity of the lower packer is low, and the labor intensity of the same output can be reduced by reducing the process; the effectiveness is high under various pressure environments, and this technology can be applied under high pressure and low pressure environments; fish used abroad The spur drilling equipment can only be used once after it goes down the well, which has limitations and high cost. Therefore, it is necessary to study a reusable downhole drilling system that can efficiently complete the branching of fishbone spurs.

Contents of the invention

Aiming at the above-mentioned problems in the prior art that conventional fracturing pollutes the environment, the fishbone drilling equipment cannot be reused, and the cost is high, the present invention provides a reusable fishbone type multi-branch drilling system.

In order to achieve the above purpose, this application proposes a reusable fishbone type multi-branch drilling system, which includes a drilling assembly support bracket, an outer cylinder assembly, a connecting body, a hydraulic reciprocating push-pull rod, multiple drill bits, A plurality of flexible pipes and a plurality of driving turbines, a plurality of drill bit passages are arranged in the drilling assembly support body, and each drill bit is connected with a corresponding flexible pipe, and the flexible pipes are connected to the driving turbine Above, the driving turbines are all located in the outer cylinder assembly, one end of the outer cylinder assembly is sealed and connected with the drilling assembly support bracket, and the other end is sealed and connected with the connecting body. The connecting shaft, the hydraulic reciprocating push-pull rod is connected with each driving turbine through the soft connecting shaft.

Further, it also includes a push-pull position measurement and control system, which is provided with a displacement sensor located at the end of the hydraulic reciprocating push-pull rod.

Further, the outer cylinder assembly provides forward rotary drilling passages for a plurality of drive turbines.

Further, the plurality of drill passages form a certain angle in the drilling assembly support body, and the angle is set according to different mines.

Further, a plurality of crown parabolas are evenly distributed on each drill bit, and grooves are arranged between two adjacent crown parabolas.

Furthermore, each flexible pipe includes a mandrel and an outer pipe, and the annular gap between the two serves as a fluid channel.

Furthermore, the diameter of each flexible drill pipe is ≤φ30mm.

Furthermore, the driving turbine drives the corresponding flexible pipe and the drill bit to rotate under the driving force of the circulating drilling fluid.

Furthermore, the driving turbine drives the corresponding flexible pipe and the drill bit forward or backward under the action of the circulating drilling fluid interception and the hydraulic reciprocating push-pull rod.

Further, when the drill bit and the flexible pipe are drilled into the drilling assembly support bracket body, they are respectively sealed by dynamic sealing rings.

As a further step, the push-pull position measurement and control system is also provided with a controller connected with the hydraulic reciprocating push-pull rod.

As a further step, the data collected by the displacement sensor is transmitted to the ground parameter collection device through a cable.

Compared with the prior art, the above technical solution adopted by the present invention has the following advantages: a reusable fishbone spur type multi-branch drilling system provided by the present invention solves the problem of the flexible pipe after drilling. The problem that the hole cannot be reused in the future can realize the repeated use of a single tool. The application of downhole fishbone spur branch drilling depth measurement acquisition and control technology realizes acquisition while drilling, and enables the drilling to be carried out in a controlled manner. By collecting position data, it is ensured that the flexible pipe and the drill bit can be recovered and reused, and then the system is lifted or lowered to change to the position of the main wellbore, and the drilling operation of the fishbone branch hole is resumed. Compared with the existing one-time multi-branch production increase technology, the present invention achieves major technological innovations in recycling and reuse technology, multi-branch positioning measurement and control. The single well saves the higher cost due to one-time multi-branch completion, which has significant economic benefits, and also has the advantages of simple installation, light weight, suitable length, and no use limitations.

Description of drawings

Fig. 1 is a sectional view of the reusable fishbone type multi-branch drilling system in the embodiment.

Description of serial numbers in the figure: 1-drilling assembly support bracket body, 2-drill bit A, 3-drill bit B, 4-drill bit C, 5-flexible tube A, 6-flexible tube B, 7-flexible tube C, 8-drive turbine A, 9-drive turbine B, 10-drive turbine C, 11-soft coupling shaft, 12-hydraulic reciprocating push-pull rod, 13-push-pull position measurement and control system, 14-cable, 15-outside Barrel assembly, 16-connector.

Detailed ways

In order to make the purpose, technical solution and advantages of the present application clearer, the present application will be further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the present application, and are not used to limit the present application, that is, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the application generally described and illustrated in the figures herein may be arranged and designed in a variety of different configurations.

Accordingly, the following detailed description of the embodiments of the application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely represents selected embodiments of the application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without making creative efforts belong to the scope of protection of the present application.

It should be noted that the term "comprising", "comprising" or any other variation thereof is intended to cover a non-exclusive inclusion such that a process, method, article or apparatus comprising a set of elements includes not only those elements, but also includes none other elements specifically listed, or also include elements inherent in such a process, method, article, or device. Without further limitations, an element defined by the statement "comprising..." does not exclude the presence of additional same elements in the process, method, article or device comprising said element.

It should be noted that like numerals and letters denote similar items in the following figures, therefore, once an item is defined in one figure, it does not require further definition and explanation in subsequent figures.

In the description of the present invention, it should also be noted that, unless otherwise clearly specified and limited, the terms "installation", "installation", "connection" and "connection" should be understood in a broad sense, for example, it may be a fixed connection, It can also be 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 intermediary, and it can be the internal communication of two components. Those of ordinary skill in the art can understand the specific meanings of the above terms in the present invention in specific situations.

Example 1

Connect the fishbone spur type multi-branch drilling system into the drill string, go down to the required drilling position, and start drilling the fishbone spur branch hole. When the drilling depth reaches the design requirement, the flexible pipe will be retracted automatically. The drill string is lowered or raised, and the position is changed to drill the next group of branch holes. In this way, a set of system can be used repeatedly, and the drilling operation of multiple groups of fishbone branch holes can be carried out continuously. It can be used for drilling new open hole holes for multiple times of fishbone small branch holes, and it can also be used as an old well to increase production. The measure is to drill old openhole wells or cased wells and screen wells that can be drilled multiple times to drill small branch holes with fishbone spines to improve the connectivity of the main wellbore and increase the drainage area of the formation, thereby improving the recovery rate and oil and gas. The output of the well not only protects the environment, but also reduces the cost.

As shown in Figure 1, a reusable fishbone spur type multi-branch drilling system includes a drilling assembly support body, an outer cylinder assembly, a connecting body, a hydraulic reciprocating push-pull rod, multiple drill bits, multiple Flexible pipes and multiple driving turbines, three drill bits, three flexible pipes and three driving turbines are used as examples in this embodiment and the accompanying drawings, including drill bit A, drill bit B, drill bit C, flexible pipe A, Flexible pipe B, flexible pipe C, drive turbine A, drive turbine B, drive turbine C. There are three drill bit passages in the drilling assembly support bracket body, wherein drill bit A is connected to drive turbine A through flexible tube A, drill bit B is connected to drive turbine B through flexible tube B, and drill bit C is connected to drive turbine B through flexible tube B. The pipe C is connected with the driving turbine C; the driving turbine A, the driving turbine B, and the driving turbine C are all located in the outer cylinder assembly, one end of the outer cylinder assembly is sealed and connected with the drilling assembly support bracket, and the other end is It is sealed and connected with the connecting body, and a soft connecting shaft is arranged in the connecting body, and the hydraulic reciprocating push-pull rod is connected with each driving turbine through the soft connecting shaft.

When drilling, the above-mentioned reusable fishbone type multi-branch drilling system is connected to the drill string, lowered into the downhole where the hole needs to be drilled, and then the pump is turned on to circulate, and the drilling fluid enters the outer cylinder assembly 15. At this time, the drilling The power of the liquid flow makes the driving turbine A8, the driving turbine B9 and the driving turbine C10 rotate, respectively drives the flexible tube A5, the flexible tube B6 and the flexible tube C7 to rotate, and then respectively drives the drill bit A2, the drill bit B3, and the drill bit C4 to rotate. Because of the throttling effect of the three sets of turbines, under the action of the drilling fluid pressure and the hydraulic reciprocating push-pull rod, the driving turbine A8, the driving turbine B9 and the driving turbine C10 move forward. The pipe B6 and the flexible pipe C7 exert a certain thrust, and transmit these thrusts to the drill bit A2, the drill bit B3, and the drill bit C4 respectively, so that the three drill bits will drill into the formation under the double action of the rotating force and the driving force, pushing and pulling The position measurement and control system monitors its drilling position in real time and controls the drilling speed. When the displacement sensor detects that the drilling depth reaches the design requirements, the hydraulic reciprocating push-pull rod is activated, and the flexible pipe and drill bit are pulled back to the initial position by driving the turbine. At this time, the limit switch in the push-pull position measurement and control system sends a signal to the surface parameters. collection equipment. After the downhole drilling system has been recovered on the ground, the drill string is lifted or lowered, the position is changed, and the drilling operation of the next group of fishbone branch holes is started.

The foregoing descriptions of specific exemplary embodiments of the present invention have been presented for purposes of illustration and description. These descriptions are not intended to limit the invention to the precise form disclosed, and obviously many modifications and variations are possible in light of the above teaching. The exemplary embodiments were chosen and described in order to explain the specific principles of the invention and its practical application, thereby enabling others skilled in the art to make and use various exemplary embodiments of the invention, as well as various Choose and change. It is intended that the scope of the invention be defined by the claims and their equivalents.

Claims (12)

1. A reusable fishbone spur type multi-branch drilling system is characterized in that it includes a drilling assembly support bracket body, an outer cylinder assembly, a connecting body, a hydraulic reciprocating push-pull rod, a plurality of drill bits, a plurality of A flexible pipe and a plurality of driving turbines, a plurality of drill bit passages are provided in the drilling assembly support body, each drill bit is connected to a corresponding flexible pipe, and the flexible pipe is connected to the driving turbines, The driving turbines are all located in the outer cylinder assembly, one end of the outer cylinder assembly is sealed and connected with the drilling assembly support bracket body, and the other end is sealed and connected with the connecting body, and a soft connecting shaft is arranged in the connecting body , the hydraulic reciprocating push-pull rod is connected with each driving turbine through the soft coupling shaft. 2. A reusable fishbone spur type multi-branch drilling system according to claim 1, characterized in that it also includes a push-pull position measurement and control system, which is provided with a displacement position at the end of the hydraulic reciprocating push-pull rod. sensor. 3 . A reusable fishbone type multi-branch drilling system according to claim 1 , wherein the outer cylinder assembly provides a forward rotary drilling channel for a plurality of driving turbines. 4 . 4. A reusable fishbone spur type multi-branch drilling system according to claim 1, characterized in that, a plurality of drill passages form a certain angle in the drilling assembly support bracket body, and the angle depends on different Mine is set. 5. A reusable fishbone spur type multi-branch drilling system according to claim 1, characterized in that, each drill bit is evenly distributed with a plurality of crown parabolas, and a crown parabola is arranged between adjacent two crown parabolas. There are grooves. 6. A reusable fishbone spur type multi-branch drilling system according to claim 1, wherein each flexible tube includes a mandrel and an outer tube, and the annular gap between the two serves as a fluid channel . 7. A reusable fishbone spur type multi-branch drilling system according to claim 1, characterized in that the diameter of each flexible drill pipe is ≤φ30mm. 8. A reusable fishbone spur type multi-branch drilling system according to claim 1, characterized in that the driving turbine drives the corresponding flexible pipe and the drill bit to rotate under the action of circulating drilling fluid. 9. A reusable fishbone spur type multi-branch drilling system according to claim 1, characterized in that the drive turbine drives the corresponding flexible The pipe and the drill bit are advanced or retracted. 10. A reusable fishbone spur type multi-branch drilling system according to claim 1, characterized in that, when the drill bit and the flexible tube are drilled into the drilling assembly support body, they are respectively passed through a dynamic seal The ring is sealed. 11. A reusable fishbone spur type multi-branch drilling system according to claim 2, characterized in that the push-pull position measurement and control system is further provided with a controller connected with a hydraulic reciprocating push-pull rod. 12. A reusable fishbone spur type multi-branch drilling system according to claim 2, characterized in that the data collected by the displacement sensor is transmitted to the ground parameter collection device through a cable.

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