Axial valve control type torsion impactor and control method

Abstract

The invention relates to an axial valve control type torsion impactor and a control method, and belongs to the field of drilling tools. The impactor comprises an outer pipe body, an outer cavity, a main valve chamber, an auxiliary valve chamber, an impact hammer, a hammer seat, a lower valve plate, a switching valve and a flow guide and sand removal mechanism. A return runner is arranged between the outer pipe body and the outer cavity, an impact runner is arranged between the outer cavity and the main valve chamber, and a feedback runner is arranged between the main valve chamber and the auxiliary valve chamber. The on-off state of the feedback flow channel is dynamically controlled by the position of the impact hammer. The control method comprises the following steps that the switching valve is driven to move axially by controlling the pressure of liquid in the flow channel, and the axial displacement of the switching valve is utilized to trigger the circumferential impact action of the impact hammer. Through collaborative innovation of an axial valve control framework, a runner-cavity linkage mechanism and a flow guide sand removal system, the industrial problems of poor adaptability of small aperture, insufficient reliability, high energy consumption and the like are solved while the efficient rock breaking performance is maintained.

Description

Technical Field

[0001] The invention belongs to the field of drilling tools and relates to an axial valve-controlled torsion impactor and a control method. Background Art

[0002] In the field of deep hole hard rock drilling, the torque impactor is a highly efficient rock-breaking tool that can convert hydraulic energy into torsional impact kinetic energy, significantly improving the drilling efficiency in hard formations. In the existing technology, mainstream torque impactors usually integrate a set of rotary waterway control valve groups inside the hammer, and realize the switching of the water flow channel through the relative movement of the hammer and the valve assembly in the circumferential direction, thereby driving the circumferential impact action of the hammer. However, this type of design requires complex rotary waterway control components to be accommodated in a limited space, resulting in a large overall radial size of the tool. Although this structure performs well in large-diameter drilling scenarios such as oil and gas drilling, in underground coal mine operations, the borehole diameter is usually much smaller than the oil and gas drilling specifications. The outer diameter of the existing torque impactor is difficult to adapt to the narrow underground working environment, which greatly limits its application in the coal mining field.

[0003] Further research has shown that existing rotary valve control solutions have inherent defects: on the one hand, the precise matching of circumferential rotary valve components requires extremely high manufacturing process requirements, and long-term use is prone to wear and tear leading to seal failure; on the other hand, the rotary motion requires sufficient radial space to accommodate the movement trajectory of the valve body, further exacerbating the expansion of the tool's outer diameter. These problems are particularly prominent in small-diameter drilling scenarios in coal mines, not only reducing tool reliability but also increasing the complexity and cost of underground operations. Although the industry has attempted to improve by simplifying the valve group or optimizing the flow path layout, the basic structural principle of the rotary valve has limited its radial size to achieve a breakthrough reduction. Summary of the Invention

[0004] In view of this, the purpose of the present invention is to provide an innovative axial valve-controlled torsion impactor. Different from the traditional rotary valve design, the present invention abandons the circumferential motion control mechanism and adopts an axially movable switching valve structure. By arranging the control valve group along the axial direction of the tool and using the fluid pressure to drive the linear displacement of the switching valve, the flow channel can be opened and closed and switched. This design not only avoids the occupation of radial space by the rotary valve assembly, but also significantly reduces the overall outer diameter of the tool by optimizing the flow channel layout and the chamber linkage relationship. In addition, the axially moving switching valve is dynamically coupled with the displacement of the impact hammer, and a closed-loop control is formed through the pressure regulation of the feedback flow channel, which further improves the accuracy and stability of the impact action. This technological breakthrough effectively solves the adaptation problem of existing torsion impactors in small-diameter drilling scenarios in coal mines, while taking into account the efficiency and reliability of the tool.

[0005] In order to achieve the above object, the present invention provides the following technical solutions:

[0006] The present invention relates to an axial valve-controlled torsion impactor and its control method, suitable for deep-hole hard rock drilling, particularly for small-diameter drilling in coal mines. The impactor comprises an outer tube, an outer cavity, a main valve chamber, a secondary valve chamber, an impact hammer, a hammer seat, a lower distribution plate, a switching valve, and a diversion and sand removal mechanism.

[0007] A return flow channel is provided between the outer tube body and the outer cavity, an impact flow channel is provided between the outer cavity and the main valve chamber, and a feedback flow channel is provided between the main valve chamber and the auxiliary valve chamber. An impact chamber, a return chamber, and a feedback chamber are formed between the impact hammer, the hammer seat, and the lower distribution plate. The impact flow channel is connected to the impact chamber, and the return flow channel is connected to the return chamber. The on-off state of the feedback flow channel is dynamically controlled by the position of the impact hammer to achieve selective connection between the feedback chamber and the feedback flow channel. The switching valve is axially arranged in the main valve chamber and can move axially between the upper limit position and the lower limit position: when the switching valve is in the upper limit position, the impact flow channel is connected to the return flow channel; when the switching valve is in the lower limit position, the impact chamber and the return chamber are blocked, and the impact flow channel is connected to the interior.

[0008] Optionally, the switching valve has a groove at its upper end and a through hole communicating with the interior at its lower end. Furthermore, the groove and the inner wall of the main valve chamber form a pressure regulating chamber for balancing the axial movement resistance of the switching valve.

[0009] Optionally, the diversion and sand removal mechanism includes a diversion cover and a diversion seat. The outlet end of the diversion cover adopts a tapered flow channel design, and a water outlet hole is opened on the side wall; the outlet end of the diversion seat is extended with a long diversion tube, and its outlet position is closer to the outlet end of the diversion cover than the water outlet hole of the diversion cover.

[0010] Furthermore, the outlet end of the long flow guide tube extends to the end of the tapered flow channel of the flow guide cover, and the outlet direction thereof is parallel to the axial center line of the flow guide cover.

[0011] Optionally, a step is provided at the contact position between the switching valve and the feedback flow channel to form a pressure-holding chamber of the switching valve.

[0012] Optionally, the effective action area of ​​the impact hammer in the impact chamber is larger than the effective action area of ​​the impact hammer in the feedback chamber. When the impact hammer moves to the end of the impact stroke, the feedback flow channel of the lower distribution plate is connected to the feedback chamber.

[0013] The control method of the present invention includes the following steps: controlling the fluid pressure in the flow channel to drive the axial movement of the switching valve, and utilizing the axial displacement of the switching valve to trigger the circumferential impact of the hammer. When the switching valve is in the upper limit position, the impact flow channel communicates with the return flow channel, and the fluid pressure drives the hammer to perform the return motion. When the switching valve is in the lower limit position, the impact flow channel communicates with the impact chamber, and the fluid pressure drives the hammer to perform the impact motion. The displacement of the hammer is adjusted by dynamically controlling the on / off state of the feedback flow channel to adjust the axial position of the switching valve, forming a periodic impact cycle.

[0014] Optionally, the on-off state of the feedback flow channel is triggered by the impact hammer at the end of the impact stroke, so that the feedback chamber is connected to the feedback flow channel, thereby changing the force state of the switching valve and driving its axial movement.

[0015] The beneficial effects of the present invention are:

[0016] This invention, through its axial valve-controlled structural design, achieves breakthrough technical optimization in deep-hole hard rock drilling, especially in small-diameter drilling scenarios in coal mines. Its core innovations and derivative benefits are as follows:

[0017] 1. Significantly reduce radial dimensions and break through the bottleneck of coal mine operations

[0018] Streamlined design: The traditional torque impactor's rotating waterway control valve group is abandoned, and the circumferential motion control mechanism is replaced with an axial linear motion switching valve. The valve body is arranged along the tool axis, eliminating the rigid radial space occupied by the rotating valve group.

[0019] Compact flow channel layout: Through the axial layered integration of the return flow channel, impact flow channel and feedback flow channel, the flow channel system is embedded in the sandwich space between the outer tube body and the outer cavity, greatly reducing the outer diameter of the tool.

[0020] 2. Improve the accuracy and reliability of impact action

[0021] Dynamic closed-loop control mechanism:

[0022] The impact hammer displacement is selectively connected to the feedback chamber and the feedback flow channel to adjust the axial position of the switching valve in real time.

[0023] When the impact hammer moves to the end of its stroke, the feedback flow channel is automatically connected, driving the switching valve to move upward to switch the flow channel, forming a closed-loop control of "displacement-pressure feedback-valve position switching".

[0024] Anti-eccentric load impact design:

[0025] The effective action area of ​​the impact hammer in the impact chamber is larger than that in the feedback chamber, ensuring that the liquid pressure always drives the impact action first;

[0026] The return chamber and the impact chamber are symmetrically distributed to offset the radial eccentric load moment and avoid seal failure caused by abnormal vibration of the tool.

[0027] 3. Enhance anti-pollution ability and service life

[0028] High-efficiency diversion and sand removal mechanism:

[0029] Efficient separation is achieved based on the difference in inertia between solid and liquid phases. High-density solid particles (such as rock chips and gravel) have great inertia and are difficult to follow the sudden change in fluid direction. They maintain a straight motion trajectory and hit the inner wall of the guide cover.

[0030] After the particles are decelerated by collision, they are discharged from the diversion holes on the side wall of the deflector under the action of gravity;

[0031] The low-density liquid phase fluid has a small inertia and can change its flow direction along with the expanded diameter section at the end of the tapered flow channel and be output through the long guide tube of the guide seat;

[0032] The long guide pipe extends to the end of the tapered flow channel, and its outlet direction is strictly parallel to the axial centerline, which directionally flushes the moving area of ​​the switching valve to avoid valve body sticking due to sand accumulation.

[0033] Low resistance valve control system:

[0034] The groove at the upper end of the switching valve and the inner wall of the main valve chamber form a pressure regulating chamber to balance the pressure difference between the upper and lower ends of the valve body and reduce the axial movement resistance;

[0035] The stepped pressure-holding chamber design utilizes local high pressure to drive the switching valve to respond quickly, avoiding action delays caused by sand in the fluid.

[0036] 4. Energy saving and consumption reduction and improved drilling efficiency

[0037] Efficient conversion of hydraulic energy:

[0038] When the switching valve is in the lower limit position, the impact flow channel directly connects to the impact chamber, and the liquid pressure is converted into the torsional kinetic energy of the impact hammer without loss;

[0039] During the return phase, residual pressure is released through the pressure relief channel to reduce system energy consumption.

[0040] Adaptive hard rock formations:

[0041] Through periodic impact cycles (impact → feedback trigger → return → reset), high-frequency torsional impact effectively cracks hard formations such as granite and quartzite.

[0042] 5. Manufacturing and maintenance cost optimization

[0043] Simplified process structure: The axial valve body only requires precision turning, which reduces the difficulty of processing the arc-shaped sealing surface of the traditional rotary valve group;

[0044] Modular design of wearing parts: key components such as the guide cover and switching valve adopt detachable modules to shorten the time of underground replacement.

[0045] In summary, the present invention, through the collaborative innovation of the axial valve control structure, the flow channel-chamber linkage mechanism and the diversion and sand removal system, while maintaining efficient rock breaking performance, overcomes industry problems such as poor adaptability to small apertures, insufficient reliability, and high energy consumption, providing a revolutionary tool for hard rock drilling in underground coal mines.

[0046] Other advantages, objects, and features of the present invention will be described in part in the following description and, in part, will be apparent to those skilled in the art upon examination of the following or may be learned from practice of the present invention. The objects and other advantages of the present invention may be realized and obtained through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention will be described in detail below with reference to the accompanying drawings, in which:

[0048] Figure 1 Schematic diagram of the structure of the present invention;

[0049] Figure 2 The present invention Figure 1 AA view in the;

[0050] Figure 3 Schematic diagram of the hammer structure of the present invention.

[0051] Figure numerals: 1 outer tube body, 2 guide cover, 3 main valve chamber, 4 switching valve, 5 upper distribution plate, 6 impact hammer, 7 lower joint, 8 hammer seat, 9 lower distribution plate, 10 core tube, 11 auxiliary valve chamber, 12 outer cavity, 13 guide seat, 14 upper joint, 201 guide hole, 401 drain hole, 601 feedback trigger chamber, 801 return chamber, 802 impact chamber, I return flow channel, Ⅱ feedback flow channel, Ⅲ impact flow channel. DETAILED DESCRIPTION

[0052] The following describes the embodiments of the present invention by means of specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present invention, and the following embodiments and features in the embodiments can be combined with each other without conflict.

[0053] Among them, the accompanying drawings are only for illustrative purposes and represent only schematic diagrams rather than actual pictures, and should not be understood as limiting the present invention. In order to better illustrate the embodiments of the present invention, some parts of the accompanying drawings may be omitted, enlarged or reduced, and do not represent the dimensions of actual products. For those skilled in the art, it is understandable that some well-known structures and their descriptions may be omitted in the accompanying drawings.

[0054] The same or similar numbers in the drawings of the embodiments of the present invention correspond to the same or similar parts; in the description of the present invention, it should be understood that if there are terms such as "upper", "lower", "left", "right", "front", "back", etc. indicating directions or positional relationships, they are based on the directions or positional relationships shown in the drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operate in a specific direction. Therefore, the terms describing the positional relationship in the drawings are only used for illustrative purposes and cannot be understood as limiting the present invention. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to specific circumstances.

[0055] See also Figures 1 to 3 The impactor includes an outer tube body 1, a flow guide cover 2, a main valve chamber 3, a switching valve 4, an upper distribution plate 5, an impact hammer 6, a lower joint 7, a hammer seat 8, a lower distribution plate 9, a core tube 10, an auxiliary valve chamber 11, an outer cavity 12, a flow guide seat 13, an upper joint 14, and a guide hole 201, a leakage hole 401, a feedback trigger chamber 601, a return chamber 801, and an impact chamber 802 integrated in the above structure, and is provided with a return flow channel I, a feedback flow channel II, and an impact flow channel III.

[0056] 1. Overall structural layout

[0057] Drilling fluid diversion path: Drilling fluid enters the diversion seat 13 from the upper joint 14 and is accelerated through the tapered flow channel of the diversion cover 2. Large solid particles flow out from under the diversion cover 2 due to inertia; the filtrate enters the main valve chamber 3 area through the diversion hole 201.

[0058] Axial valve control system: Switching valve 4 is axially mounted within main valve chamber 3. Its upper end is provided with a groove (forming a pressure-regulating chamber with the inner wall of main valve chamber 3) and its lower end is provided with a through hole. A step is provided at the contact surface between switching valve 4 and feedback flow channel II, forming a pressure-holding chamber for the switching valve.

[0059] Impact actuator: The impact hammer 6 is installed between the hammer base 8 and the lower valve plate 9. The three of them form a return chamber 801, an impact chamber 802, and a feedback trigger chamber 601. The effective area of ​​the impact hammer 6 in the impact chamber 802 is larger than that in the feedback trigger chamber 601.

[0060] 2. Workflow

[0061] (1) Impact stroke start (switching valve 4 is in the lower limit position)

[0062] The liquid is divided into two paths:

[0063] One way is to impact the upper end of the switching valve 4 through the guide cover 2, pushing it to maintain the lower limit position;

[0064] The other path passes through the guide hole 201 → impact flow channel III → impact chamber 802, and at the same time passes through the return flow channel I → return chamber 801.

[0065] Impact action: Because the effective action area of ​​the impact hammer 6 in the impact chamber 802 is larger, and the two chambers 801 / 802 are symmetrically distributed ( Figure 2 ), the liquid pressure drives the impact hammer 6 to rotate clockwise until it hits the hammer seat 8 to generate a torsional impact.

[0066] (2) Feedback triggering and valve position switching

[0067] When the impact hammer 6 moves to the impact end point, its structure triggers the feedback flow channel II of the lower distribution plate 9 to communicate with the feedback trigger chamber 601 ( Figure 3 ).

[0068] The high-pressure liquid enters the pressure-holding chamber of the switching valve through the feedback flow channel II, pushing the switching valve 4 upward to the upper limit position.

[0069] (3) Return motion (switching valve 4 is at the upper limit position)

[0070] Flow channel switching:

[0071] The impact flow channel III is connected to the low-pressure area through the leakage hole 401;

[0072] The return flow channel I is connected to the high-pressure area of ​​the guide hole 201.

[0073] Return action: the impact chamber 802 is depressurized, and the return chamber 801 maintains high pressure. The pressure difference drives the impact hammer 6 to rotate counterclockwise and reset.

[0074] (4) Cycle reset

[0075] When the impact hammer 6 moves counterclockwise to the limit position, the feedback trigger chamber 601 is disconnected from the feedback flow channel II;

[0076] The upper end of the switching valve 4 loses pressure balance and moves downward to the lower limit position under the action of the fluid, restarting the impact stroke to form a periodic impact cycle.

[0077] 3. Collaboration among core institutions

[0078] Diversion and sand removal mechanism ( Figure 1 ):

[0079] The long guide tube of the guide seat 13 extends to the end of the tapered flow channel of the guide cover 2, and the outlet direction is parallel to the axial centerline;

[0080] Large particles flow out from the neck hole under the action of inertia, and the long guide tube outputs clean liquid in a direction to the switching valve 4 area.

[0081] Feedback control accuracy assurance:

[0082] Impact hammer 6 displacement precise control feedback flow channel II on and off;

[0083] The switching valve's pressure-holding chamber uses a step surface to accumulate pressure, ensuring a quick response of the valve body.

[0084] Anti-eccentric load design:

[0085] The return chamber 801 and the impact chamber 802 are arranged symmetrically around the circumference to offset the radial unbalanced torque;

[0086] The rigid support structure of the core tube 10 and the outer tube body 1 suppresses vibration transmission.

[0087] This embodiment achieves efficient impact in small-aperture hard rock drilling by replacing the rotary valve group with axial valve control, dynamic linkage between flow channel and chamber, and coordinated diversion and sand removal. Figure 2 As shown, the circumferential motion path of the impact hammer 6 is strictly matched with the flow channel pressure switching, ensuring the reliability and adaptability of underground coal mine drilling.

[0088] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not limiting. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention can be modified or replaced by equivalents without departing from the purpose and scope of the technical solutions, which should all be included in the scope of the claims of the present invention.

Claims

1. An axial valve-controlled torsion impactor, characterized in that: include: An outer tube body (1), an outer cavity (12), a main valve chamber (3), an auxiliary valve chamber (11), an impact hammer (6), a hammer seat (8), a lower distribution plate (9), and a switching valve (4); A return flow channel (I) is provided between the outer tube body (1) and the outer cavity (12), an impact flow channel (III) is provided between the outer cavity (12) and the main valve chamber (3), and a feedback flow channel (II) is provided between the main valve chamber (3) and the auxiliary valve chamber (11); An impact chamber (802), a return chamber (801) and a feedback chamber (601) are formed between the impact hammer (6), the hammer seat (8) and the lower distribution plate (9), wherein: The impact flow channel (III) is in communication with the impact chamber (802), and the return flow channel (I) is in communication with the return chamber (801); The on / off state of the feedback flow channel (II) is dynamically controlled by the position of the impact hammer (6) to achieve selective communication between the feedback chamber (601) and the feedback flow channel (II); The switching valve (4) is axially arranged in the main valve chamber (3), and the switching valve (4) can move axially between an upper limit position and a lower limit position: When the switching valve (4) is in the upper limit position, the impact flow channel (III) is connected to the return flow channel (I); When the switching valve (4) is in the lower limit position, the impact chamber (802) and the return chamber (801) are blocked, and the impact flow channel (III) is connected to the interior.

2. The axial valve-controlled torsion impactor according to claim 1, characterized in that: The switching valve (4) is provided with a groove at the upper end and a through hole communicating with the interior at the lower end.

3. The axial valve-controlled torsion impactor according to claim 2, characterized in that: The groove of the switching valve (4) and the inner wall of the main valve chamber (3) form a pressure regulating chamber for balancing the axial movement resistance of the switching valve (4).

4. The axial valve-controlled torsion impactor according to claim 1, characterized in that: The invention also includes a diversion and sand removal mechanism, which includes a diversion cover (2) and a diversion seat (13). The outlet end of the diversion cover (2) adopts a tapered flow channel design, and a water outlet hole (201) is opened on the side wall. The water outlet end of the diversion seat (13) is extended with a diversion long pipe, and the outlet position of the diversion long pipe is closer to the outlet end of the diversion cover than the water outlet hole (201) of the diversion cover (2).

5. The axial valve-controlled torsion impactor according to claim 1, characterized in that: A step is provided at the contact position between the switching valve (4) and the feedback flow channel (II), forming a switching valve pressure-holding chamber.

6. The axial valve-controlled torsion impactor according to claim 1, characterized in that: The effective action area of ​​the impact hammer (6) in the impact chamber (802) is larger than its effective action area in the feedback chamber (601); when the impact hammer (6) moves to the end of the impact stroke, the feedback flow channel (II) of the lower distribution plate (9) is connected to the feedback chamber (601).

7. The axial valve-controlled torsion impactor according to claim 4, characterized in that: The outlet end of the long flow guide tube extends to the end of the tapered flow channel of the flow guide cover (2).

8. The axial valve-controlled torsion impactor according to claim 7, characterized in that: The outlet direction of the long flow-guiding tube is parallel to the axial center line of the flow-guiding cover (2).

9. A control method of the axial valve-controlled torsion impactor according to any one of claims 1 to 8, characterized in that: The following steps are involved: The liquid pressure in the control flow channel is driven to drive the switching valve (4) to move axially, and the axial displacement of the switching valve (4) is used to trigger the circumferential impact action of the impact hammer (6); When the switching valve (4) is in the upper limit position, the impact flow channel (III) is connected to the return flow channel (I), and the liquid pressure drives the impact hammer (6) to perform the return movement; When the switching valve (4) is in the lower limit position, the impact flow channel (III) is connected to the impact chamber (802), and the liquid pressure drives the impact hammer (6) to perform the impact movement; The displacement of the impact hammer (6) is adjusted by dynamically controlling the on-off state of the feedback flow channel (II) to adjust the axial position of the switching valve (4), thereby forming a periodic impact cycle.

10. The method according to claim 9, characterized in that: The on / off state of the feedback flow channel (II) is triggered by the impact hammer (6) at the end of the impact stroke, so that the feedback chamber (601) is connected to the feedback flow channel (II), thereby changing the force state of the switching valve (4) and driving its axial movement.

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