Flow control valve of dynamic pushing type rotary guiding system

Abstract

The invention discloses a flow control valve of a dynamic pushing type rotary guiding system, which comprises an upper disc valve and a lower disc valve which are in coaxial running fit, the upper disc valve is provided with a first valve hole, the lower disc valve is provided with a plurality of second valve holes, the number of the second valve holes is not less than three, and the first valve hole can be communicated with the second valve holes in the rotating process of the lower disc valve; wherein the first valve hole is a fan-shaped valve hole, the circle center where the first valve hole is located is located at the central axis of the upper disc valve, the multiple second valve holes are distributed in the lower disc valve in a central symmetry mode, the second valve holes are fan-shaped valve holes, and the circle centers where the second valve holes are located are located at the central axis of the lower disc valve. According to the flow control valve of the dynamic pushing type rotary guiding system, the flow of slurry entering the lower disc valve and the overlapping area are in a linear relation, the flow switching linearity of the entering slurry is improved, and it is guaranteed that the guiding force change is linear.

Description

Technical Field

[0001] The invention relates to the field of drilling equipment, and in particular to a flow control valve of a dynamic push-type rotary guide system. Background Art

[0002] For the exploitation of hydrocarbons, such as oil and natural gas, steerable drilling technology is generally used. The core of steerable drilling technology is to use a rotary steerable drilling system to complete the guidance, so as to find the sweet spot according to the planned trajectory. The dynamic push-type rotary steerable system can make full use of mud to break rocks, carry rocks and guide. It has attracted widespread attention because its structure is simpler than that of static push-type and pointing rotary steerable systems.

[0003] The function of the flow valve in the dynamic push-to-pull rotary steering system is to distribute mud of different flow rates into the circumferentially arranged palm, so that different pressure differences are generated in the circumferentially arranged palm and the annulus. The pressure difference pushes the palm to extend and push against the well wall. Thus, through the distribution of the flow valve, the well wall generates reaction forces of different directions and sizes on the rotary steering system, that is, the guiding force. The current flow valve adopts an upper and lower disc valve structure. When the lower disc valve rotates with the rotary steering system, the upper disc valve is stabilized at a certain angle under the control of the stable platform, and the mud always enters the palm in the same circumferential direction. The common lower disc valve adopts a three-window structure. Most of them are circular windows arranged circumferentially in China, and Schlumberger abroad adopts arc windows. When the upper disc valves all use arc windows, if the lower disc valves use circular windows, when the lower disc valves rotate with the rotary steering system, the overlapping area of ​​the upper disc valve window and the lower disc valve window increases or decreases nonlinearly, and the switching linearity of the incoming mud flow is poor, which will cause the guiding force change to be nonlinear. Summary of the invention

[0004] In order to solve the above technical problems, the present invention provides a flow control valve of a dynamic push-type rotary guide system, so that the mud flow entering the lower disc valve is linearly related to the overlapping area, thereby improving the linearity of the switching of the incoming mud flow and ensuring that the guide force change is also linear.

[0005] The present invention provides a flow control valve of a dynamic push-type rotary guide system, comprising: an upper disc valve and a lower disc valve that rotate together coaxially, the upper disc valve having a first valve hole, the lower disc valve having a plurality of second valve holes, the second valve holes being no less than three, and the first valve hole being able to communicate with the second valve holes during the rotation of the lower disc valve; wherein the first valve hole is a fan-shaped valve hole, the center of which is located at the center axis of the upper disc valve, the plurality of second valve holes are distributed in the lower disc valve in a centrally symmetrical manner, and each second valve hole is a fan-shaped valve hole, the center of which is located at the center axis of the lower disc valve.

[0006] Optionally, there are four second valve holes, and the four second valve holes are centrally symmetrically distributed on the lower disc valve.

[0007] Optionally, the central angle of the first valve hole is α1, the central angle of the second valve hole is β1, and the interval angle between two adjacent second valve holes is β2, wherein α1>β1>β2.

[0008] Optionally, α1>β1+β2.

[0009] Optionally, 2*β1+2*β2≥α1≥β1+2*β2.

[0010] Optionally, the outer radius of the fan-shaped valve hole of the upper disc valve is r s1 , the inner radius of the fan-shaped valve hole of the upper disc valve is r s2 , the outer radius of the fan-shaped valve hole of the lower disc valve is r d2 , the inner radius of the fan-shaped valve hole of the upper disc valve is r d1 , where r s1 >r d2 , r s2 <r d1 .

[0011] Optionally, each second valve hole is connected to a piston, each piston is connected to a push rib plate, and the drilling fluid passes through the second valve hole to push the piston to drive the push rib plate to move.

[0012] Compared with the prior art, the beneficial effects of the present invention are as follows: a flow control valve of a dynamic push-type rotary guide system provided by the present invention opens a plurality of concentric second valve holes in the lower disc valve, and designs the second valve holes as fan-shaped valve holes, which cooperate with the fan-shaped valve holes of the first valve holes of the upper disc valve. As the lower disc valve rotates, the overlapping area between the first valve hole of the upper disc valve and the second valve hole of the lower disc valve increases or decreases linearly. According to the flow continuity principle, the mud flow entering the lower disc valve is linearly related to the overlapping area, that is, Q=AV, Q is the cement slurry flow rate, A is the overlapping area, and V is the cement slurry flow rate, which will make the guiding force change linear, and make the continuity of the control of the direction of travel of the drilling tool better. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 A schematic diagram of the structure of an upper disc valve provided in an embodiment of the present invention;

[0014] Figure 2 A schematic diagram of the structure of a lower disc valve provided in an embodiment of the present invention;

[0015] Figure 3 A schematic diagram of the overall structure of a dynamic push-type rotary guide system provided in an embodiment of the present invention;

[0016] Figure 4 It is a comparative schematic diagram of flow control related data of the flow control valve of the dynamic push-type rotary guide system provided in an embodiment of the present invention.

[0017] Description of reference numerals:

[0018] 1. Stable control platform; 2. Drilling fluid main flow channel; 3. Upper disc valve; 31. First valve hole; 4. Lower disc valve; 41. Second valve hole; 5. Piston; 6. Push rib plate; 7. Valve disc connecting rod; 8. Centralizer. DETAILED DESCRIPTION

[0019] The specific implementation of the present invention is described in detail below, but it should be understood that the protection scope of the present invention is not limited by the specific implementation. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0020] At present, the flow valve adopts an upper and lower disc valve structure. When the lower disc valve rotates with the rotary guide system, the upper disc valve is stabilized at a certain angle under the control of the stable platform, and the mud always enters the valve in the same circumferential direction. The common lower disc valve adopts a three-window structure. Domestically, most of them are circular windows with a circumferential layout, and Schlumberger abroad adopts arc windows. When the upper disc valves all use arc windows, if the lower disc valve uses a circular window, when the lower disc valve rotates with the rotary guide system, the overlapping area of ​​the upper disc valve window and the lower disc valve window increases or decreases nonlinearly. According to the flow continuity principle, the mud flow entering the lower disc valve is nonlinearly related to the overlapping area, that is, Q=AV, Q is the cement slurry flow rate, A is the overlapping area, and V is the cement slurry flow rate. Therefore, the switching linearity of the incoming mud flow is poor, which will also cause the guide force change to be nonlinear.

[0021] To this end, an embodiment of the present invention provides a flow control valve of a dynamic push-type rotary guide system, which can make the mud flow entering the lower disc valve linearly related to the overlapping area, improve the linearity of the switching of the incoming mud flow, and ensure that the guide force change is also linear.

[0022] At least one embodiment of the present invention provides a flow control valve of a dynamic push-type rotary guide system, comprising: an upper disc valve and a lower disc valve that rotate coaxially, the upper disc valve having a first valve hole, the lower disc valve having a plurality of second valve holes, the second valve holes being no less than three, and the first valve hole being able to communicate with the second valve holes during the rotation of the lower disc valve; wherein the first valve hole is a fan-shaped valve hole, the center of which is located at the center axis of the upper disc valve, the plurality of second valve holes are distributed in a centrally symmetrical manner on the lower disc valve, and each second valve hole is a fan-shaped valve hole, the center of which is located at the center axis of the lower disc valve.

[0023] In the flow control valve of the dynamic push-type rotary guide system provided by the above embodiment of the present invention, by making the mud flow entering the lower disc valve linearly related to the overlapping area, the switching linearity of the incoming mud flow is improved, ensuring that the guide force change is also linear.

[0024] The present invention is described below by several specific embodiments. In order to keep the following description of the embodiments of the present invention clear and concise, the detailed description of known functions and known components may be omitted. When any component of the embodiments of the present invention appears in more than one accompanying drawings, the component may be represented by the same reference numeral in each of the accompanying drawings.

[0025] refer to Figure 1 and Figure 2 , Figure 1 A schematic diagram of the structure of the upper disc valve provided in an embodiment of the present invention, Figure 2 A schematic diagram of the structure of the lower disc valve provided by an embodiment of the present invention is shown in FIG. Figure 1 and Figure 2 As shown, an embodiment of the present invention provides a flow control valve of a dynamic push-type rotary guide system, including an upper disc valve 3 and a lower disc valve 4 that rotate coaxially, the upper disc valve 3 having a first valve hole 31, the lower disc valve 4 having a plurality of second valve holes 41, and the second valve holes 41 are not less than three. During the rotation of the lower disc valve 4, the first valve hole 31 can be connected to the second valve hole 41, wherein the first valve hole 31 is a fan-shaped valve hole, and the center of the circle where the first valve hole 31 is located is located at the central axis of the upper disc valve 3, and the plurality of second valve holes 41 are distributed in a centrally symmetrical manner on the lower disc valve 4, and each second valve hole 41 is a fan-shaped valve hole, and the center of the circle where the second valve hole 41 is located is located at the central axis of the lower disc valve 4.

[0026] The present invention provides a plurality of concentric second valve holes in the lower disc valve, and designs the second valve holes as fan-shaped valve holes, which cooperate with the fan-shaped valve holes of the first valve holes of the upper disc valve. As the lower disc valve rotates, the overlapping area between the first valve hole of the upper disc valve and the second valve hole of the lower disc valve increases or decreases linearly. According to the flow continuity principle, the mud flow entering the lower disc valve is linearly related to the overlapping area, that is, Q=AV, Q is the cement slurry flow rate, A is the overlapping area, and V is the cement slurry flow rate. This will make the guide force change linear, and the control continuity of the direction of travel of the drilling tool will be better. The fan-shaped second valve hole can ensure that the flow increase and decrease have good linearity. Figure 4 , Figure 4 FIG. 1 is a schematic diagram for comparing flow control related data of a flow control valve of a dynamic push-to-pull rotary guide system provided in an embodiment of the present invention. Figure 4 As shown in the figure, taking a second valve hole as an example, compared with a circular hole with the same flow area, the orifice is set to be fully open at the beginning, and the flow rate is 20L / s. When the orifice is closed at a certain angle, the comparison of the flow rate changes over time is as follows: Figure 4 shown.

[0027] The current lower valve disc has only three windows, and the overlapping area variation range of the upper and lower disc valve windows is also smaller. Therefore, the adjustable range of the guide force is small, and the three windows have a small adjustable range for the guide force.

[0028] Based on the above problems, the present invention provides a flow control valve of a dynamic push-type rotary guide system with four second valve holes 41, and the four second valve holes 41 are centrally symmetrically distributed on the lower disc valve 4. Since the lower disc valve has four fan-shaped second valve holes 41, the overlapping area variation range of the first valve hole 31 of the upper disc valve 3 and the second valve hole 42 of the lower disc valve 4 is also increased, thereby increasing the adjustable range of the guiding force. At the same time, since each second valve hole 41 corresponds to a rear push-up rib 6, the four second valve holes 41 are four push-up ribs 6. However, if the number of second valve holes 41 is too large, more push-up ribs 6 will be required, which will make the mechanical structure more complicated and reduce the system reliability. In addition, too many second valve holes 41 will reduce the structural strength. Therefore, four second valve holes 41 are the best choice.

[0029] Specifically, in this embodiment, a flow control valve of a dynamic push-to-pull rotary steering system is provided, wherein the center angle of the first valve hole 31 is α1, the center angle of the second valve hole 41 is β1, and the interval angle between two adjacent second valve holes 41 is β2, wherein α1>β1>β2. β1>β2 ensures that the flow entering from the interval of the second valve hole 41 is sufficient, thereby ensuring that the push-to-pull rib plate 6 has sufficient pressure to push the drilling tool to deflect, and at the same time ensures that the push-to-pull rib plate has sufficient push time.

[0030] Considering that if α1≤β1+β2, when the first valve hole 31 completely covers β1 of the second valve hole 41 and half of the distance between the two adjacent second valve holes 41 on both sides and the middle second valve hole 41, that is, α1 completely covers β1 and β2, when the direction of the guide force needs to be changed, the stabilizing platform drives the upper valve disc 3 to rotate and then drives the first valve hole 31 to rotate. The first valve hole 31 needs to pass through a certain angle to overlap with the adjacent second valve hole 41, which will cause a hysteresis loop of the guide force.

[0031] Therefore, in a flow control valve of a dynamic push-type rotary guide system provided in an embodiment of the present invention, α1>β1+β2.

[0032] Furthermore, 2*β1+2*β2≥α1≥β1+2*β2. α1≥β1+2*β2 can ensure that no hysteresis occurs when the direction of the guide force is switched. If α1 exceeds 2*β1+2*β2, the first valve hole 31 will completely cover the two second valve holes 41 at the same time, resulting in uneven distribution of the direction of the guide force. Therefore, in the present invention, it is necessary to ensure that 2*β1+2*β2≥α1≥β1+2*β2.

[0033] As an optional method, in order to ensure the flow rate, the radial length of the first valve hole 31 needs to be greater than the radial length of the second valve hole 41, and the outer radius of the fan-shaped valve hole of the upper disc valve 3 is r s1 , the inner radius of the fan-shaped valve hole of the upper valve 3 is r s2 , the outer radius of the fan-shaped valve hole of the lower disc valve 4 is r d2 , the inner radius of the fan-shaped valve hole of the upper valve 3 is r d1 , where r s1 >r d2 , r s2 <r d1 .

[0034] refer to Figure 3 , Figure 3 The overall structural diagram of the dynamic push-to-pull rotary guide system provided by the embodiment of the present invention is as follows: Figure 3 As shown, each second valve hole 41 is connected to a piston 5, and each piston 5 is connected to a pushing rib 6. The drilling fluid passes through the second valve hole 41 to push the piston 5 and drive the pushing rib 6 to move.

[0035] like Figure 3 As shown, the drilling fluid enters the drill collar through the middle of the stabilizer 8, and the drilling fluid flows inside the drill collar. A part of the drilling fluid flows into the upper disc valve, and a part of the drilling fluid enters the drilling fluid main flow channel 2. The stabilization control platform 1 is fixedly connected to the upper disc valve 3, and the lower disc valve 4 is fixedly connected to the drill collar through the valve disc connecting rod 7. The stabilization platform 1 is connected to the drill collar through a bearing, and the drill bit 2 is fixedly connected to the drill collar. Each second valve hole 41 in the lower disc valve 4 is connected, and each second valve hole 41 is connected to a piston 5. Each piston 5 can drive a push rib 6. The drill collar drives the lower disc valve 4, the piston 5, the pushing rib 6, and the valve disc connecting rod 7 to rotate through the rotary guide system. The stable control platform 1 drives the upper disc valve 3 to stabilize at a fixed circumferential angle under the drive of the internal motor. During the rotation of the lower disc valve 4, the second valve hole 41 always overlaps with the first valve hole 31 in the upper disc valve 3 at a fixed circumferential angle, so that the drilling fluid passing through the upper disc valve 3 always enters the piston 5 at a fixed circumferential angle and drives the corresponding pushing rib 6, which ensures the consistency of the size and direction of the pushing force. If the direction and size of the pushing force need to be changed, it is only necessary to drive the upper disc valve 3 to stabilize at different circumferential fixed angles through the stable control platform 1.

[0036] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations can be made to the embodiments without departing from the principles and spirit of the present invention, and the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A flow control valve for a dynamic push-type rotary guide system, characterized in that: The invention comprises an upper disc valve (3) and a lower disc valve (4) which are coaxially rotatable, wherein the upper disc valve (3) has a first valve hole (31), and the lower disc valve (4) has a plurality of second valve holes (41), wherein the number of the second valve holes (41) is not less than three, and during the rotation of the lower disc valve (4), the first valve hole (31) can be connected to the second valve hole (41); wherein: The first valve hole (31) is a fan-shaped valve hole, and the center of the circle where the first valve hole (31) is located is located at the central axis of the upper disc valve (3); A plurality of the second valve holes (41) are centrally symmetrically distributed on the lower disc valve (4), and each of the second valve holes (41) is a fan-shaped valve hole, with the center of the circle where the second valve hole (41) is located located at the central axis of the lower disc valve (4).

2. A flow control valve for a dynamic push-type rotary guide system as claimed in claim 1, characterized in that: There are four second valve holes (41), and the four second valve holes (41) are centrally symmetrically distributed on the lower disc valve (4).

3. A flow control valve of a dynamic push-type rotary guide system as claimed in claim 1, characterized in that: The central angle of the first valve hole (31) is α1, the central angle of the second valve hole (41) is β1, and the interval angle between two adjacent second valve holes (41) is β2, wherein α1>β1>β2.

4. A flow control valve of a dynamic push-type rotary guide system as claimed in claim 3, characterized in that: α1＞β1+β2。 5. A flow control valve of a dynamic push-type rotary guide system as claimed in claim 4, characterized in that: 2*β1+2*β2≥α1≥β1+2*β2。 6. A flow control valve of a dynamic push-type rotary guide system as claimed in claim 1, characterized in that: The outer radius of the fan-shaped valve hole of the upper disc valve (3) is r s1 The inner radius of the fan-shaped valve hole of the upper disc valve (3) is r s2 The outer radius of the fan-shaped valve hole of the lower disc valve (4) is r d2 The inner radius of the fan-shaped valve hole of the upper disc valve (3) is r d1 , wherein the r s1 >r d2 , r s2 <r d1 .

7. A flow control valve of a dynamic push-type rotary guide system as claimed in claim 2, characterized in that: Each of the second valve holes (41) is connected to a piston (5), and each of the pistons (5) is connected to a push rib (6). The drilling fluid passes through the second valve hole (41) to push the piston (5) and drive the push rib (6) to move.

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