A downhole hydraulic decoder

Abstract

The present invention relates to a downhole hydraulic decoder, which includes upper and lower end covers, upper and lower cavities, large and small fixing pins, various hydraulic pipelines, a sealing assembly, a self-locking mechanism, a thrust ball bearing, an anti-cylindrical cam, a moving sliding sleeve, a pipeline adapter plate, a hydraulic valve, a hydraulic valve fixing seat, a hydraulic valve fixing cap, a spring, and a guide rod. A hydraulic decoder controls the opening degrees of flow valves in 4 downhole oil layers through two hydraulic pipelines respectively. The two pipelines are respectively led out through a tee to form two hydraulic pipelines for controlling the movement of a piston. The other two pipelines are connected to the downhole flow valves through the decoder. When the piston moves, it pushes the self-locking mechanism, the thrust ball bearing, the anti-cylindrical cam, and the moving sliding sleeve to simultaneously compress the spring, so that the guide rod on the anti-cylindrical cam is inserted into the hydraulic valve, pushing the valve core to conduct the specified hydraulic valve, thereby enabling the first pipeline to communicate with the downhole flow valve, and the second pipeline is connected to the other end of the flow valve through the decoder. The opening degree of the downhole flow valve is controlled by controlling the pressures of the two pipelines.

Description

Technical Field

[0001] This invention patent relates to downhole intelligent completion technology, particularly to the field of hydraulic control intelligent wells, and specifically to a downhole hydraulic decoder. Background Art

[0002] With the progress of oil extraction technology and the increasing scarcity of oil resources, intelligent completion technology has developed rapidly and been widely applied. During the development of intelligent completion technology, hydraulic control intelligent well technology has always occupied a dominant position in this field due to its huge advantages. The start of intelligent completion technology in China is later than that in developed countries and is subject to some core technology monopolies. As a key component downhole in hydraulic control intelligent wells, the hydraulic decoder plays a very important role in improving oil production efficiency and quality.

[0003] The hydraulic decoder realizes the automatic layer selection action downhole by providing hydraulic power through the wellhead hydraulic power generation system and applying different pressures to different hydraulic pipelines in different sequences. Currently, most existing hydraulic decoders adopt a scheme of using 3 hydraulic control pipelines to control up to 6 production layers. At the same time, due to the large number of hydraulic control pipelines, it increases the technical difficulty when crossing the packer. How to use fewer control pipelines to achieve the selection of more layers to meet the current production requirements of oil wells is a technical problem to be solved by this invention. A downhole decoder system (CN111663922A) realizes the individual control of 6 decoder systems using three hydraulic pipelines.

[0004] To solve the above problems, the mechanism of the hydraulic decoder is innovatively designed, and a downhole hydraulic decoder is designed. Summary of the Invention

[0005] The purpose of this invention is to design a downhole hydraulic decoder, a hydraulic decoder that can control multiple layers with two hydraulic control pipelines and can realize the selection of all layers with only one single decoding device. Based on this, the hydraulic decoder can be installed at a lower well depth and placed above the downhole docking tool (i.e., the disconnecter). Once a failure occurs, without touching the downhole flow control valve, it can be directly taken out for repair or replacement, which will greatly reduce the maintenance cost of intelligent wells.

[0006] A downhole hydraulic decoder mentioned in the present invention includes an upper end cover (1), an upper cavity (2), a large fixing pin (3), a lower cavity (4), a lower end cover (5), a small fixing pin (6), a first hydraulic interface (7), a second hydraulic interface (8), a first pipeline (9), a second pipeline (10), a sealing assembly (11), a piston (12), a thrust sliding sleeve (13), a fixed sliding sleeve (14), a rotating sliding sleeve (15), a thrust ball bearing (16), an anti-cylindrical cam (17), a moving sliding sleeve (18), a pipeline adapter plate (19), a hydraulic valve (20), a hydraulic valve fixing seat (21), a hydraulic valve fixing cap (22), a spring (23), a guide rod (24), a flow control pipeline (25), and a hydraulic valve output pipeline (26). The upper end cover (1) is bolted to the upper cavity (2) through an upper end cover threaded hole (1-1). The outer wall of the upper cavity (2) has two symmetrically distributed threaded through holes for installing the large fixing pin (3). The upper end cover (1) has two pipeline holes (1-2) and two hydraulic interface holes (1-3). The first hydraulic interface (7) and the second hydraulic interface (8) are inserted into the hydraulic interface holes (1-3). The first pipeline (9) and the second pipeline (10) are inserted into the pipeline holes (1-2). The first hydraulic interface (7) and the first pipeline (9), and the second hydraulic interface (8) and the second pipeline (10) are respectively connected to two external pipelines through tees. The piston (12) is inserted into the upper end cover (1) and abuts against the inner step of the upper end cover (1). The piston (12) is also installed inside the upper cavity and is sealed by the sealing assembly (11). The sealing assembly (11) is divided into an O-ring retaining ring (11-1), an O-ring (11-2), a snap ring (11-3), and an O-ring support ring (11-4). The middle part of the piston (12) has two piston sealing grooves (12-1). The O-ring retaining ring (11-1) and the O-ring (11-2) are installed in the sealing grooves (12-1). The two sealing grooves (12-1) divide the piston (11) into two parts. The left half is used to push the piston (11) forward, and the right half is used to reset the piston (11). The upper cavity (2) internally has a first hydraulic flow channel (2-1) and a second hydraulic flow channel (2-2). The first hydraulic flow channel (2-1) communicates with the first hydraulic interface (7) to push the piston (11) forward, and the second hydraulic flow channel (2-2) communicates with the second hydraulic interface (8) to reset the piston (11). The piston (11) is connected to the thrust sliding sleeve (13) at the back. The thrust sliding sleeve (13) has 18 positioning blocks (13-1) and thrust sliding sleeve serrations (13-2). The positioning blocks (13-1) are evenly distributed with one high and one low. The thrust sliding sleeve (13) is fitted with the fixed sliding sleeve (14) through the positioning blocks (13-1). The fixed sliding sleeve (14) has fixed sliding sleeve long teeth (14-1), two first fixed pin holes (14-2), and a chute (14-3).The fixed sliding sleeve long teeth (14-1) are evenly distributed. There is a slide rail between every two long teeth, and each fixed sliding sleeve long tooth (14-1) has a chute (14-3) inside. The high and low positioning blocks (13-1) are respectively engaged with the slide rail and the chute (14-3). The thrust sliding sleeve (13) can slide within the fixed sliding sleeve (14). The two first fixed pin holes (14-2) are symmetrically distributed. The fixed sliding sleeve (14) is fixed by inserting a large fixed pin (3) installed in the upper cavity (2) into the first fixed pin hole (14-2). The thrust sliding sleeve (13) is engaged with the rotating sliding sleeve (15) through the tooth surface of the thrust sliding sleeve serrations (13-2). The rotating sliding sleeve (15) has rotating sliding sleeve long teeth (15-1). The tooth surface of the rotating sliding sleeve long teeth (15-1) is engaged with the tooth surface of the thrust sliding sleeve serrations (3-2), and the rotating sliding sleeve long teeth (15-1) are engaged with the fixed sliding sleeve (14) through the slide rail. The bottom surface of the rotating sliding sleeve (15) is engaged with a thrust ball bearing (16). The other side of the thrust ball bearing (16) is engaged with a reverse cylindrical cam (17). The reverse cylindrical cam (17) has a cam chute (17-1) and a guide rod fixing threaded hole (17-2). A large fixed pin (3) is inserted into the cam chute (17-1). The large fixed pin (3) is fixed to the lower cavity (4) by threading. The lower cavity (4) is engaged with the upper cavity (3) by threading. The lower cavity (4) is engaged with the lower end cover (5) by bolts. The guide rod fixing threaded hole (17-2) is engaged with the guide rod fixing threaded end (24-2) of the guide rod (24). The guide rod (24) has a guide rod pushing end (24-1) and a guide rod fixing end (24-2). The guide rod pushing end (24-1) can connect or close the hydraulic valve (20) along with the movement of the reverse cylindrical cam (17). The hydraulic valve (20) has a hydraulic valve inlet (20-1), a hydraulic valve outlet (20-2), a hydraulic valve mechanical control port (20-3), and a hydraulic valve threaded fixing end (20-4). The hydraulic valve mechanical control port (20-3) controls the opening and closing of the hydraulic valve (20) with the insertion and extraction of the guide rod pushing end (24-1). The hydraulic valve threaded fixing end (20-4) is inserted into the hydraulic valve fixing hole (21-1) of the hydraulic valve fixing seat (21) and is engaged with the hydraulic valve fixing cap (22) by threading to fix the hydraulic valve (20). The hydraulic valve fixing seat (21) has a hydraulic fixing hole (21-1), a layered pipeline hole (21-2), a flow control pipeline channel (21-3), and a fixed pin hole (21-4). The fixed pin hole (21-4) inserts a small fixed pin (6) to fix the hydraulic valve fixing seat (21). The small fixed pin (6) is installed in the lower cavity (4) by threading. The reverse cylindrical cam (17) is installed with a moving sliding sleeve (18) through surface engagement. A spring (23) is installed on the other end surface of the moving sliding sleeve (18). The other end of the spring (23) is installed inside the lower end cover (5).And against the step surface.

[0007] The first pipeline (9) and the second pipeline (10) are connected to the first pipeline interface (19-1-1) and the second pipeline interface (19-2-2) respectively through the pipeline hole (1-2); the first pipeline (9) is connected to each hydraulic valve (20) through the layered connection plate (19-1) and is connected to the hydraulic valve output pipeline (26) through the hydraulic valve outlet (20-2); the hydraulic valve output pipeline (26) enters the formation through the layered pipeline hole (21-2) and the hydraulic valve output pipeline hole (5-3); the second pipeline (10) is connected to the flow control pipeline (25) through the flow valve connection plate (19-2); the flow control pipeline enters the formation through the flow control pipeline channel (21-3) and the flow control pipeline channel (5-2).

[0008] The above-mentioned hydraulic valve (20) is a two-position two-way valve, which is equivalent to a hydraulic switch. When the valve core in the hydraulic valve (20) is subjected to the thrust applied by the guide rod (24) entering the mechanical control port (20-3) of the hydraulic valve, the oil circuit will be opened to connect the hydraulic valve inlet (20-1) and the hydraulic valve outlet (20-2).

[0009] Compared with the prior art, the present invention has the following beneficial effects:

[0010] (1) The present invention can achieve selection and control of multiple layers with only two hydraulic control pipelines, greatly reducing the number and length of downhole pipelines. At the same time, the reduction in the number of pipelines also reduces the technical difficulty of penetrating the packer;

[0011] (2) The present invention separates the hydraulic decoder from the flow control valve, and only one decoder is used to achieve the selection and control of all layers, which effectively reduces the size and complexity of the flow control valve and greatly reduces the number of hydraulic decoders;

[0012] (3) The present invention adopts a combination of hydraulic drive and mechanical movement to select and lock the floor, which makes the structure simpler and improves the stability of the mechanism movement, avoiding the problem that the decoder cannot work normally due to a certain path disconnection;

[0013] (4) The hydraulic decoder is designed in the present invention to be located at a shallower well depth and is placed above the downhole disconnector. The hydraulic decoder can be installed or removed together with the disconnector, which is convenient for later maintenance or replacement.

[0014] (5) The present invention can realize the layer selection and self-locking functions of the decoder with relatively small pressure, which greatly improves the stress conditions of various internal structures. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is a three-view appearance of a downhole hydraulic decoder;

[0016] Figure 2 Front view and top view of the internal part assembly of a downhole hydraulic decoder;

[0017] Figure 3 Cross-sectional view of the sealing structure of a downhole hydraulic decoder;

[0018] Figure 4 Structure diagram of the upper end cover of a downhole hydraulic decoder;

[0019] Figure 5 Structure diagram of the lower end cover of a downhole hydraulic decoder;

[0020] Figure 6 Structure diagram of the thrust sliding sleeve of a downhole hydraulic decoder;

[0021] Figure 7 Structure diagram of the fixed sliding sleeve of a downhole hydraulic decoder.

[0022] Figure 8 Structure diagram of the rotating sliding sleeve of a downhole hydraulic decoder.

[0023] Figure 9 Structure diagram of the anti-cylindrical cam of a downhole hydraulic decoder.

[0024] Figure 10 Structure diagram of the pipeline joint of a downhole hydraulic decoder.

[0025] Figure 11 Structure diagram of the hydraulic valve of a downhole hydraulic decoder.

[0026] Figure 12 Structure diagram of the hydraulic valve fixing seat of a downhole hydraulic decoder.

[0027] Figure 13 Structure diagram of the guide rod of a downhole hydraulic decoder;

[0028] Figure 14 Control schematic diagram of a downhole hydraulic decoder.

[0029] In the figure: 1 - upper end cap; 2 - upper cavity; 3 - large fixing pin; 4 - lower cavity; 5 - lower end cap; 6 - small fixing pin; 7 - first hydraulic interface; 8 - second hydraulic interface; 9 - first pipeline; 10 - second pipeline; 11 - sealing assembly; 12 - piston; 13 - thrust sliding sleeve; 14 - fixed sliding sleeve; 15 - rotating sliding sleeve; 16 - thrust ball bearing; 17 - anti-cylindrical cam; 18 - moving sliding sleeve; 19 - pipeline connection plate; 20 - hydraulic valve; 21 - hydraulic valve fixing seat; 22 - hydraulic valve fixing cap; 23 - spring; 24 - guide rod; 25 - flow control pipeline; 26 - hydraulic valve output pipeline. 1-1, upper end cap threaded hole; 1-2, pipeline hole; 1-3, hydraulic interface hole; 2-1, first hydraulic flow channel; 2-2, second hydraulic flow channel; 5-1, lower end cap threaded hole; 5-2, flow control pipeline channel; 5-3, hydraulic valve output pipeline hole; 11-1, O-ring retaining ring; 11-2, O-ring; 11-3, snap ring; 11-4, O-ring support ring; 12-1, piston sealing groove; 13-1, positioning block; 13-2, thrust sliding sleeve saw teeth; 14-1, fixed sliding sleeve long teeth; 14-2, first fixing pin hole; 14-3, chute; 15-1, rotating sliding sleeve long teeth; 17-1, cam chute; 17-2 guide rod fixing threaded hole; 19-1, layered connection plate; 19-1-1, first pipeline interface; 19-1-2, hydraulic valve interface; 19-2, flow valve connection plate; 19-2-1, second pipeline interface; 19-2-2, flow control pipeline interface; 20-1, hydraulic valve inlet; 20-2, hydraulic valve outlet, 20-3, hydraulic valve mechanical control port; 20-4, hydraulic valve threaded fixing end; 21-1, hydraulic valve fixing hole; 21-2, layered pipeline hole; 21-3, flow control pipeline channel; 21-4, second fixing pin hole; 24-1, guide rod pushing end; 24-2, guide rod fixing threaded end. Detailed implementation mode

[0030] Combined with the attached Figure 1 and the attached Figure 2 , the present invention is further described as follows:

[0031] A downhole hydraulic encoder mentioned in the present invention includes an upper end cap (1), an upper cavity (2), a large fixing pin (3), a lower cavity (4), a lower end cap (5), a small fixing pin (6), a first hydraulic interface (7), a second hydraulic interface (8), a first pipeline (9), a second pipeline (10), a sealing assembly (11), a piston (12), a thrust sliding sleeve (13), a fixed sliding sleeve (14), a rotating sliding sleeve (15), a thrust ball bearing (16), an anti-cylindrical cam (17), a moving sliding sleeve (18), a pipeline connection plate (19), a hydraulic valve (20), a hydraulic valve fixing seat (21), a hydraulic valve fixing cap (22), a spring (23), a guide rod (24), a flow control pipeline (25), a hydraulic valve output pipeline (26);

[0032] The large fixing pin (3) and the small fixing pin (6) are threadedly installed on the upper cavity (2) and the lower cavity (4). The upper cavity (2) and the lower cavity (4) are respectively bolted to the upper end cover (1) and the lower end cover (5), and the upper and lower cavities are threadedly fitted together;

[0033] The first hydraulic interface (7) and the first pipeline (9), and the second hydraulic interface (8) and the second pipeline (10) are respectively connected to the external pipelines through tees. The first hydraulic interface (7) and the second hydraulic interface (8) communicate with the internal flow channel of the upper cavity (2) through the upper end cover (1). The piston (12) is installed inside the upper cavity (2) and is sealed by the sealing assembly (11), and at the same time abuts against the upper end cover (1). When the first hydraulic interface (7) is pressurized, the piston (12) is pushed to move. The piston (12) pushes the thrust sliding sleeve (13), the rotating sliding sleeve (15), the thrust ball bearing (16), the anti-cylindrical cam (17) and the moving sliding sleeve (18) to move, and at the same time compresses the spring (23). During the movement of the anti-cylindrical cam (17), the guide rod (24) is driven to insert into the hydraulic valve (20), and the valve core is pushed to make the hydraulic valve (20) conduct, realizing layer selection. When the first hydraulic interface (7) is depressurized and the second hydraulic interface (8) is pressurized, under the action of hydraulic pressure and the spring, the piston (12) resets, and the guide rod (24) is pulled out of the hydraulic valve (20), closing the hydraulic valve (20) to prepare for the next layer selection. Since there is only one guide rod (24), different oil layer flow valves can be selected by conducting different hydraulic valves (20);

[0034] Combined with the attached Figure 3 , the present invention is further described as follows:

[0035] The upper cavity (2) and the piston (12), wherein the upper cavity (2) has a first hydraulic flow channel (2-1) and a second hydraulic flow channel (2-2), which are respectively connected to the external pipelines through the first hydraulic interface (7) and the second hydraulic interface (2). The piston (12) has two sealing grooves (12-1) for sealing between the piston (12) and the upper cavity (2). The sealing grooves (12-1) divide the piston (12) into left and right parts. The first hydraulic flow channel (7) communicates with the left half of the piston (12), and the second hydraulic flow channel (8) communicates with the right half of the piston (12). By controlling the pressure entering the two hydraulic flow channels, the movement of the piston (12) is controlled.

[0036] The described sealing assembly (11) is composed of an O-ring retaining ring (11-1), an O-ring (11-2), a snap ring (11-3), and an O-ring support ring (11-4). Among them, every two O-ring retaining rings (11-1) and one O-ring (11-2) form a sealing unit. There are 5 groups of sealing units between the piston (12) and the upper cavity (2) to achieve the sealing effect. At the same time, the snap ring (11-3) and the sealing groove inside the upper cavity (2) limit the movement range of the piston (12).

[0037] Combined with the attached Figure 4 and the attached Figure 5 , the present invention will be further described:

[0038] Both the upper end cover (1) and the lower end cover (5) have internal steps, threaded holes, and various pipeline holes. The internal step of the upper end cover (1) is used to abut against the piston (12), and the internal step of the lower end cover (5) is used to abut against the spring (23). At the same time, the upper cavity (2) and the lower cavity (4) are respectively connected by bolts.

[0039] Combined with the attached Figure 6 and the attached Figure 7 and the attached Figure 8 , the present invention will be further described:

[0040] The thrust sleeve (13), the fixed sleeve (14) and the rotating sleeve (15) form a self-locking mechanism, wherein one end of the thrust sleeve (13) is designed with 18 saw teeth (13-2), the thrust sleeve (13) has an equal number of positioning blocks (13-1) uniformly distributed in height in the circumferential direction, the positioning blocks (13-1) are used to limit the axial movement of the thrust sleeve (13), the center of the positioning blocks (13-1) coincides with the center of the bottom saw teeth (13-2), the fixed sleeve (14) has a fixed sleeve long tooth (14-1), a first fixed pin hole (14-2) and a sliding The fixed sleeve (14) is fixed by a large fixed pin (3) installed in the first fixed pin hole (14-2). There are 9 slide rails between the fixed sleeve teeth (14-1), and there are 9 slide grooves (14-3) in the fixed sleeve teeth (14-1). High and low positioning blocks (13-1) are respectively installed, so that the thrust sleeve (13) can only move in the axial direction. The rotating sleeve (15) has 9 rotating sleeve teeth (15-1) installed in the slide rail of the fixed sleeve (14). The tooth surface of the thrust sleeve serration (13-1) and the rotating sleeve teeth are aligned with each other. The tooth surfaces of the thrust sleeve (13) and the rotating sleeve (15) are in close contact. Before the self-locking structure is locked, the thrust sleeve (13) is installed inside the fixed sleeve (14). The high and low positioning blocks (13-1) thereon are respectively stuck in the slide rail and the slide groove (14-3). The long teeth (15-1) of the rotating sleeve are installed in the slide rail. However, at this time, the thrust sleeve (13) and the rotating sleeve (15) have only half of the contact area in each slide rail. The thrust sleeve (13) moves under the action of the piston (12). Due to the restriction of the fixed sleeve (14), it can only move axially. When the rotating sleeve (15) moves to the fixed slide rail, the thrust sleeve (13) and the rotating sleeve (15) can only move axially. When the thrust sleeve (13) and the rotating sleeve (15) are in contact with each other in an inclined manner and only contact half of each other's area, the rotating sleeve (15) is subjected to a circumferential force under the action of the thrust of the piston (12) and the bottom spring (23). The force forces the rotating sleeve (15) to rotate at a certain angle. At this time, the rotating sleeve (15) is in full contact with the thrust sleeve (13) and the inclined surface of the fixed sleeve (14).When the hydraulic control pipeline is depressurized, under the action of the spring (23), the rotating sleeve (15) pushes the thrust sleeve (13) to move axially until the long teeth (15-1) of the rotating sleeve are completely in contact with the inclined surface of the fixed sleeve (14), realizing the self-locking of the structure. Since the position of the rotating sleeve (15) is completely restricted by the fixed sleeve (14), it cannot move at this time. When unlocking is required, only pressurize to the corresponding pressure. At this time, the thrust sleeve (13) still pushes the rotating sleeve (15) to move axially. When the rotating sleeve (15) is completely separated from the fixed sleeve (14), the inclined surface where the thrust sleeve (13) contacts the rotating sleeve (15) provides a circumferential rotating force to the rotating sleeve (15) again. Then the hydraulic control pipeline is depressurized. Under the action of the spring (23), the long teeth (15-1) of the rotating sleeve move into the slide rail of the fixed sleeve (14) again, and the self-locking structure returns to the initial position, and the unlocking is successful.

[0041] Combined with the attached Figure 9 , the present invention will be further described:

[0042] The anti-cylindrical cam (17) has a cam chute (17-1) and a guide rod fixing threaded hole (17-2). The large fixing pin (3) is fixed in the lower cavity (4) by threads and inserted into the cam chute (17-1), so that the anti-cylindrical cam (17) realizes axial movement and circumferential rotation when pushed by the sleeve. When moving to a specific position, the guide rod (24) installed in the guide rod fixing threaded hole (17-2) will conduct the hydraulic valve (20) at a specific layer. At the same time, the self-locking mechanism locks the movement of the anti-cylindrical cam (17) to realize layer selection. When the self-locking mechanism is unlocked, the large fixing pin (3) in the cam chute (17-1) rotates the anti-cylindrical cam (17) again and pulls out the guide rod (24) to close the hydraulic valve (20), and the anti-cylindrical cam (17) is prepared to open the next hydraulic valve (20);

[0043] Combined with the attached Figure 10 , attached Figure 11 , attached Figure 12 and attached Figure 13 , the present invention will be further described:

[0044] The pipeline adapter (19), hydraulic valve (20), hydraulic valve fixing seat (21) and guide rod (24) are described. Among them, the pipeline adapter (19) is divided into a layered adapter (19-1) and a flow valve adapter (19-2). The layered adapter (19-1) has a first pipeline interface (19-1-1) and a hydraulic valve interface (19-1-2). The flow valve adapter (19-2) has a second pipeline interface (19-2-1) and a flow control pipeline interface (19-2-2). The hydraulic valve (20) has a hydraulic valve inlet (20-1), a hydraulic valve outlet (20-2), a hydraulic valve mechanical control port (20-3) and a hydraulic valve threaded fixing end (20-4). The hydraulic valve fixing seat (21) has a hydraulic valve fixing hole (21-1), a layered pipeline hole (21-2), a flow control pipeline channel (21-3) and a second fixing pin hole (21-4). The guide rod (24) has a guide rod pushing end (24-1) and a guide rod fixed threaded end (24-2). The layered adapter (19-1) and the flow valve adapter (19-2) are connected together by welding. Among them, the layered adapter (19-1) is used to conduct the first pipeline (9) and each hydraulic valve (20). The flow valve adapter (19-2) is used to conduct the second pipeline (10) and the flow control pipeline (25). The flow control pipeline (25) enters the flow valves in each oil layer through the flow control pipeline channel (21-3). The guide rod pushing end (24-1) enters the hydraulic valve mechanical control (20-3) port to push the valve core, conduct the hydraulic valve inlet (20-1) and the hydraulic valve outlet (20-2), connect the first pipeline (9) with the corresponding hydraulic valve output pipeline (26) and enter the flow valves in each oil layer through the layered pipeline hole (21-2). Furthermore, by adjusting the opening of the flow valves in the hydraulic control oil layer in the first pipeline (9) and the second pipeline (10), the hydraulic valve threaded fixing end (20-4) is inserted into the hydraulic valve fixing hole (21-1) and is threadedly connected to the hydraulic valve fixing cap (22) to fix the hydraulic valve (20) on the hydraulic valve fixing seat (21). The small fixing pin (6) is threadedly installed in the lower cavity (4) and inserted into the second fixing pin hole (21-4) to fix the hydraulic valve fixing seat (21);

[0045] Combined with the attached Figure 14 , the present invention will be further described as follows:

[0046] The first pipeline (9) and the second pipeline (10) are respectively connected to two external hydraulic control pipelines. The first pipeline (9) is connected to different hydraulic valves (20) through the layered adapter (19-1). The specified hydraulic valve (20) is conducted through the downhole hydraulic decoder, so as to connect the flow control valves in the specified oil layer. The second pipeline (10) is connected to the flow control pipeline (25) through the flow valve adapter (19-2). The flow control pipeline (25) is connected to each flow valve downhole. The flow valves downhole are controlled by controlling the hydraulic pressure in the two hydraulic pipelines.

[0047] The present invention is a downhole hydraulic decoder, and the implementation methods of its various functions are as follows:

[0048] Taking the selected pay zone 1 as an example, its working principle is as follows:

[0049] Before pressurization, the four hydraulic valves (20) in the hydraulic decoder are all in the closed state. When pressurizing, the second pipeline (10) is pressurized first and maintained at a constant pressure. At this time, the anti-cylindrical cam (17) moves forward and rotates by half a slot position. A guide rod (24) is installed on the anti-cylindrical cam (17). After moving to the specified position, the hydraulic valve (20) controlling the pay zone 1 is conducted through a mechanical method, and at the same time, the self-locking structure is started to lock the layer selection structure. Since there is only one guide rod (24), only one hydraulic valve (20) can be conducted every time it rotates by half a slot position. At this time, the other three hydraulic valves (20) are still in the closed state. At this time, the first pipeline (9) is pressurized, and the hydraulic oil has only two flow directions, that is, the hydraulic cavity of the hydraulic decoder and the hydraulic cavity of the flow control valve in the pay zone 1 through the hydraulic valve (20). By coordinating the pressures of the first pipeline (9) and the second pipeline (10), the opening degree adjustment of the flow control valve in the pay zone 1 can be realized;

[0050] When it is necessary to control the pay zone 2, the hydraulic valve (20) should be closed first. At this time, the first pipeline (9) is depressurized, the second pipeline (10) is pressurized, and after maintaining the pressure, it is depressurized, and the self-locking mechanism is unlocked. Then the first pipeline (9) is pressurized to push the piston (12) to move. At the same time, under the action of the spring (23), the rotor resets and rotates by half a slot position again. So far, the control of the pay zone 1 is completed. The control of other horizons needs to repeat the above operations.

[0051] At the same time, in order to accurately understand the situation of the pay zone selected by the hydraulic decoder, a vacant position is also designed. When the guide rod (24) moves to the position of the vacant position, no hydraulic valve (20) is conducted. At this time, pressurizing the first pipeline (9) again cannot control the flow control valves of any pay zones. When the pressure causes the piston (12) of the decoder to move a certain displacement, there is no passage. Since the hydraulic signal acts slowly underground and the deeper the well depth, the faster the signal attenuation, when the vacant position is selected, the pressure signal propagation distance of the first pipeline (9) is short and can be easily recognized, so as to more accurately understand the layer selection situation of the hydraulic decoder.

[0052] The above are only some preferred examples of the present invention. Any person skilled in the art can modify the above-described technical solutions or modify them into equivalent technical solutions. Therefore, any simple modification or equivalent replacement made according to the technical solutions of the present invention belongs to the scope protected by the present invention.

Claims

1. A downhole hydraulic decoder, comprising an upper end cap, an upper cavity, a large fixing pin, a lower cavity, a lower end cap, a small fixing pin, a first hydraulic interface, a second hydraulic interface, a first pipeline, a second pipeline, a sealing assembly, a piston, a thrust sliding sleeve, a fixed sliding sleeve, a rotating sliding sleeve, a thrust ball bearing, an anti-cylindrical cam, a moving sliding sleeve, a pipeline connection plate, a hydraulic valve, a hydraulic valve fixing seat, a hydraulic valve fixing cap, a spring, a guide rod, a flow control pipeline, and a hydraulic valve output pipeline, characterized in that, The described first hydraulic interface and the first pipeline, as well as the second hydraulic interface and the second pipeline, are respectively connected to the external pipeline through tees. The first hydraulic interface and the second hydraulic interface are connected to the internal flow channel of the upper cavity through the upper end cover. The piston is installed inside the upper cavity, sealed by a sealing assembly, and simultaneously abuts against the upper end cover. When the pressure of the first hydraulic interface increases, it pushes the piston to move. The piston pushes the thrust sliding sleeve, the rotating sliding sleeve, the thrust ball bearing, the anti-cylindrical cam, and the moving sliding sleeve to move, and at the same time compresses the spring. During the movement, the anti-cylindrical cam drives the guide rod to insert into the hydraulic valve, pushes the valve core to make the hydraulic valve conduct, realizes layer selection, adjusts the hydraulic pressure in the first hydraulic interface and the second hydraulic interface. Under the action of the hydraulic pressure and the spring, the piston resets, the guide rod is pulled out from the mechanical control port of the hydraulic valve, and the hydraulic valve is closed to prepare for the next layer selection. Since there is only one guide rod, by conducting different hydraulic valves, the flow valves in different oil layers can be controlled.

2. The downhole hydraulic decoder according to claim 1, characterized in that The described upper cavity, sealing assembly, and piston, where the upper cavity has a first hydraulic flow channel and a second hydraulic flow channel. The sealing assembly consists of an O-ring retaining ring, an O-ring, a snap ring, and an O-ring support ring. The middle part of the piston has two sealing grooves. Each two O-ring retaining rings and one O-ring form a sealing unit. There are 5 groups of sealing units between the piston and the upper cavity to achieve the sealing effect. At the same time, the snap ring and the sealing groove inside the upper cavity limit the movement range of the piston. When the pressure of the first hydraulic flow channel increases, it pushes the piston to move to the right through the left half of the piston. When resetting, the first hydraulic flow channel is depressurized, the second hydraulic flow channel is pressurized, and the piston is pushed back through the right half of the piston.

3. The downhole hydraulic decoder according to claim 1, characterized in that, The described upper end cover and the lower end cover both have internal steps and threaded holes. The internal step of the upper end cover is used to abut against the piston, and the internal step of the lower end cover is used to abut against the spring. At the same time, they are respectively connected to the upper and lower cavities through bolts.

4. The downhole hydraulic decoder according to claim 1, wherein, The thrust sleeve, fixed sleeve and rotating sleeve form a self-locking mechanism, wherein one end of the thrust sleeve is designed with 18 serrations, and the thrust sleeve has an equal number of positioning blocks with uniform height distribution in the circumference, and the positioning blocks are used to limit the axial movement of the thrust sleeve, and the center of the positioning blocks coincides with the center of the bottom serrations. The fixed sleeve has a fixed sleeve long tooth, a first fixed pin hole and a slide groove, and the fixed sleeve is fixed by a large fixed pin installed in the first fixed pin hole. There are 9 slide rails between the long teeth of the fixed sleeve, and there are 9 slide grooves in the long teeth of the fixed sleeve, which are respectively installed with high The low positioning block makes the thrust sleeve only move axially. The rotary sleeve has 9 rotary sleeve long teeth, which are installed in the slide rail of the fixed sleeve. The thrust sleeve serrated tooth surface is in close contact with the rotary sleeve long tooth surface. Before the self-locking structure is locked, the thrust sleeve is installed inside the fixed sleeve, and the high and low positioning blocks on it are respectively stuck in the slide rail and the slide groove. The rotary sleeve long teeth are installed in the slide rail, but at this time the thrust sleeve and the rotary sleeve have only half the contact area in each slide rail. The thrust sleeve moves under the action of the piston. Due to the limitation of the fixed sleeve, it can only move axially. When the rotary sleeve When the sleeve moves to the bottom end of the fixed sleeve, the long teeth of the rotating sleeve are separated from the slide rail of the fixed sleeve. Since the thrust sleeve and the rotating sleeve are in contact with each other in an inclined manner and only contact half of each other's area, the rotating sleeve will be subjected to a circumferential force under the thrust of the piston and the bottom spring. This force will force the rotating sleeve to rotate at a certain angle. At this time, the rotating sleeve is completely in contact with the thrust sleeve and the inclined surface of the fixed sleeve. When the hydraulic control pipeline is depressurized, the rotating sleeve pushes the thrust sleeve to move axially under the action of the spring until the rotating sleeve The long teeth of the sleeve are completely in contact with the inclined surface of the fixed sleeve, realizing the self-locking of the structure. Since the position of the rotating sleeve is completely restricted by the fixed sleeve, it cannot move at this time. When it needs to be unlocked, it only needs to be pressurized to the corresponding pressure. At this time, the thrust sleeve still pushes the rotating sleeve to make axial movement. When the rotating sleeve is completely separated from the fixed sleeve, the inclined surface where the thrust sleeve contacts the rotating sleeve again provides circumferential rotational force to the rotating sleeve, and then the hydraulic control pipeline is depressurized. Under the action of the spring, the long teeth of the rotating sleeve move again into the slide rail of the fixed sleeve, and the self-locking structure returns to its initial position, and the unlocking is successful.

5. A downhole hydraulic decoder according to claim 1, characterized in that, The anti-cylindrical cam is provided with a cam groove and a guide rod fixing threaded hole. A large fixing pin fixed in the lower cavity by thread is inserted into the cam groove, so that the anti-cylindrical cam can realize axial movement and circumferential rotation when pushed by the sliding sleeve. When it moves to a specific position, the guide rod installed in the guide rod fixing threaded hole will make the hydraulic valve at a specific layer open. At the same time, the self-locking mechanism locks the movement of the anti-cylindrical cam to realize layer selection. When the self-locking mechanism is unlocked, the large fixing pin in the cam groove makes the anti-cylindrical cam rotate again, and pulls out the guide rod to close the hydraulic valve. The anti-cylindrical cam is ready to open the next hydraulic valve.

6. The downhole hydraulic decoder according to claim 1, wherein, The pipeline adapter, hydraulic valve, hydraulic valve fixing seat and guide rod described above. The pipeline adapter is divided into a layered adapter and a flow valve adapter. The layered adapter has a first pipeline interface and a hydraulic valve interface. The flow valve adapter has a second pipeline interface and a flow control pipeline interface. The hydraulic valve has a hydraulic valve inlet, a hydraulic valve outlet, a hydraulic valve mechanical control port and a hydraulic valve threaded fixing end. The hydraulic valve fixing seat has a hydraulic valve fixing hole, a layered pipeline hole, a flow control pipeline channel and a second fixing pin hole. The guide rod has a guide rod pushing end and a guide rod fixed threaded end. The layered adapter and the flow valve adapter are connected together by welding. Among them, the layered adapter is used to conduct the first pipeline and each hydraulic valve. The flow valve adapter is used to conduct the second pipeline and the flow control pipeline. The flow control pipeline enters the flow valves in each oil layer through the flow control pipeline channel. The guide rod pushing end enters the hydraulic valve mechanical control port to push the valve core, conduct the hydraulic valve inlet and the hydraulic valve outlet, connect the first pipeline and the corresponding hydraulic valve output pipeline and enter the flow valves in each oil layer through the layered pipeline hole. Furthermore, by adjusting the hydraulic pressure in the first pipeline and the second pipeline to control the opening degree of the flow valves in the hydraulic control oil layer, the hydraulic valve threaded fixing end is inserted into the hydraulic valve fixing hole and is threadedly connected to the hydraulic valve fixing cap to fix the hydraulic valve on the hydraulic valve fixing seat. The small fixing pin is threadedly installed in the lower cavity and inserted into the second fixing pin hole to fix the hydraulic valve fixing seat.

7. A downhole hydraulic decoder according to claim 1, characterized in that, The first pipeline and the second pipeline are respectively connected to two external hydraulic control pipelines. The first pipeline is connected to different hydraulic valves through the layered adapter. The specified hydraulic valve is conducted through the downhole hydraulic decoder, so as to connect the flow control valve in the specified oil layer. The second pipeline is connected to the flow control pipeline through the flow valve adapter. The flow control pipeline is connected to each flow valve downhole. The flow valves downhole are controlled by controlling the hydraulic pressure of the first pipeline and the second pipeline.

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