Water pressure core pushing device and control method thereof

Abstract

The invention belongs to the field of engineering machinery, and relates to a water pressure core pushing device and a control method thereof.The water pressure core pushing device comprises a drill cylinder of a hollow cylinder structure, and a water inlet is formed in one end of the drill cylinder and used for introducing cooling water; the first material pushing plate is installed in an inner cavity of the drilling barrel in a sliding mode in the axial direction of the drilling barrel, a water outlet hole penetrating in the axial direction and a valve element installation cavity arranged in the radial direction are formed in the first material pushing plate, the valve element installation cavity communicates with the water outlet hole, and a valve element and an elastic assembly are arranged in the valve element installation cavity; the valve element is installed in the valve element installation cavity in a radial moving mode, is located at the initial position under the pretightening force effect of the elastic assembly so as to seal the water outlet hole, and moves outwards under the centrifugal force effect so as to open the water outlet hole. Through centrifugal movement of the valve element, automatic switching of water flow states in the drilling stage and the element pushing stage is achieved, and external control is not needed; water flow is used for cooling and lubricating during drilling, and closed water flow forms high pressure during core pushing so as to realize core pushing.

Description

Technical Field

[0001] The invention belongs to the field of engineering machinery and relates to a water pressure core pushing device and a control method thereof. Background Art

[0002] As a mechanical equipment widely used in geotechnical engineering, geological exploration and pile foundation construction, the core function of the water-grinding drill is to obtain cylindrical rock cores by cutting the rock formation in an annular shape through a rotating drill bit. However, the smooth discharge of the rock core has always been a technical difficulty during the construction process. In conventional water-grinding drilling operations, when the drill bit cuts into the rock formation, if there are cracks developed inside the rock mass or uneven rock properties, the rock core is prone to break and get stuck inside the coring drill bit. Since the outer diameter of the rock core is usually smaller than the inner diameter of the drill bit steel tube, coupled with the irregular shape of the broken rock core and the obstruction of residual gravel and mud inside the drill bit, the rock core is skewed and stuck in the drill bit, making it difficult to remove directly.

[0003] At present, the core pushing methods commonly used in the industry include mechanical percussion method, jacking method and split drill bit method, which have the following significant defects: Mechanical percussion method: Vibration is generated by manually knocking on the outer wall of the drill bit to loosen the core. This method relies on operating experience, and the percussion force is difficult to accurately control, which can easily cause deformation of the drill bit structure or damage to the connecting parts, and has limited effect on deep core jams. Jacking method: Insert rigid tools such as steel bars at the top opening of the drill bit (usually the drill barrel) to forcibly push out the core. This method requires frequent disassembly of equipment, limited operating space, high risk of secondary core fragmentation during jacking, and cannot achieve continuous operation. Split drill bit method: The coring drill bit is designed as a detachable two-half structure, and the core is removed by splitting the drill bit. Although this method can directly expose the stuck core, the split structure greatly weakens the overall strength of the drill bit, increases manufacturing costs, and repeated disassembly and assembly significantly reduces construction efficiency.

[0004] It is worth noting that a large amount of cooling water needs to be continuously injected during the water-grinding drilling operation to reduce the friction heat of the drill bit and lubricate the cutting surface, but the existing technologies have not effectively utilized this inherent resource. The cooling water is usually directly discharged or simply recycled, and the fluid kinetic energy contained in it is not developed to assist in core pushing, which not only wastes energy but also misses the potential technical breakthrough of simplifying the core pushing process.

[0005] In summary, the traditional water-grinding drill core pushing method generally has problems such as low efficiency, reliance on manual intervention, large equipment loss and inability to operate continuously. The existing improvement schemes are difficult to promote and apply in actual projects due to their complex structure, high cost, poor compatibility and insufficient reliability. Therefore, there is an urgent need for an innovative method that can make full use of the existing working medium (cooling water) of the water-grinding drill, has a simple structure and can achieve efficient and continuous discharge of the core. Summary of the invention

[0006] In view of this, the purpose of the present invention is to provide a water pressure core pushing device and a control method thereof, which converts the fluid pressure of cooling water into core discharge power by optimizing the internal flow channel design of the drill barrel, thereby realizing the integration and efficiency of the construction process, and further solving the problems raised in the background technology.

[0007] In order to achieve the above object, the present invention provides the following technical solutions:

[0008] A hydraulic core pushing device, comprising:

[0009] The drill tube is a hollow cylindrical structure with a water inlet at one end for the cooling water to flow in;

[0010] A first push plate is slidably installed in the inner cavity of the drill tube along the axial direction of the drill tube, wherein the first push plate is provided with an axially penetrating water outlet hole and a radially arranged valve core installation cavity, wherein the valve core installation cavity is connected to the water outlet hole and has a valve core and an elastic component built therein;

[0011] The valve core is radially movable and installed in the valve core installation cavity. It is in an initial position under the preload force of the elastic component to close the water outlet hole, and moves outward under the centrifugal force to open the water outlet hole.

[0012] Furthermore, the hydraulic core pushing device also includes:

[0013] The second pushing plate is arranged on a side of the first pushing plate away from the water inlet, and a water hole is provided on the second pushing plate.

[0014] Furthermore, the outer edge of the second push plate is clearance-matched with the inner wall of the drill tube.

[0015] Furthermore, a spacer ring is arranged between the first push plate and the second push plate; specifically, the spacer ring is a low-resistance spacer ring, which functions to reduce the resistance between the first push plate and the second push plate and form a water-passing gap between the first push plate and the second push plate.

[0016] Furthermore, a sealing assembly is provided on the contact surface between the first pusher plate and the drill tube to prevent leakage of cooling water.

[0017] Furthermore, a plug is provided at one end of the valve core installation cavity away from the water outlet, which is used to fix the spring and close the valve core installation cavity.

[0018] Furthermore, the elastic component is a spring.

[0019] Furthermore, a sealing assembly is provided on the contact surface between the first pusher plate and the drill tube to prevent leakage of cooling water.

[0020] Furthermore, the sealing component is a sealing ring.

[0021] On the other hand, a control method of a hydraulic core pushing device is also provided, based on the above hydraulic core pushing device, comprising the following steps:

[0022] Drilling stage:

[0023] The drill tube is driven to rotate and drill, and the core pushes the first push plate to move toward the water inlet;

[0024] The valve core is subjected to the centrifugal force to overcome the pre-tightening force of the elastic component, opening the water outlet, and the cooling water flows to the core contact surface through the water outlet;

[0025] Core pushing stage:

[0026] Stop the rotation of the drill tube, and reset the valve core to close the water outlet;

[0027] Continuous water injection forms a closed cavity. When the water pressure rises to the set threshold, the first push plate is pushed out at a constant speed to push the core out and withdraw the drill tube from the borehole.

[0028] Furthermore, after the core pushing stage is completed, water injection is stopped and the first pusher plate is pushed to reset by the next cycle of cores.

[0029] The beneficial effects of the present invention are:

[0030] First of all, the hydraulic core pushing device innovatively uses the centrifugal force generated during the rotation of the drill barrel to control the on and off of the water flow. During the drilling stage, the rotation of the drill barrel drives the valve core to overcome the preload of the elastic component, thereby opening the water outlet, allowing the cooling water to accurately flow to the core contact surface, effectively meeting the cooling needs during the drilling process. During the core pushing stage, the drill barrel stops rotating, and the valve core automatically resets to close the water outlet, forming a closed cavity. Through continuous water injection, the water pressure rises to the set threshold and pushes the first push plate to push the core out at a constant speed. This design not only ensures the stability of the core pushing process, but also realizes the precise control of the water flow, greatly improving the efficiency of drilling and core pushing.

[0031] Secondly, the device performs well in water conservation. When the drill tube does not rotate, the valve core remains closed due to the elastic component, so no water will flow out. Considering that most of the time in the drilling process is auxiliary time, this design significantly reduces the waste of water resources and achieves the goal of water conservation and environmental protection.

[0032] Finally, the device realizes the function of automatic core pushing, which greatly liberates manpower and simplifies the construction steps. Traditional drilling devices require manual operation during the core pushing process, which is not only labor-intensive but also poses safety hazards. This device uses water pressure to push the first push plate to realize the automatic pushing of the core, which not only ensures the safety of construction workers but also improves construction efficiency. More importantly, this innovative design solves major problems in the industry and provides new ideas and methods for the development of drilling technology.

[0033] Other advantages, objectives and features of the present invention will be described in the following description to some extent, and to some extent, will be obvious to those skilled in the art based on the following examination and study, or can be taught from the practice of the present invention. The objectives and other advantages of the present invention can be realized and obtained through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] 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 in conjunction with the accompanying drawings, wherein:

[0035] Figure 1 It is a schematic diagram of the structure of the drill tube in the conventional core pushing method;

[0036] Figure 2 Schematic diagram of the structure of a water pressure core pushing device in the embodiment (drilling state);

[0037] Figure 3 Schematic diagram of the structure of a water pressure core pushing device in the embodiment (core pushing state);

[0038] Figure 4 It is a partial structural schematic diagram of a water pressure core pushing device in the embodiment;

[0039] Figure 5 It is a flow chart of a control method of a water pressure core pushing device in an embodiment.

[0040] Figure numerals: 1-drill barrel, 2-first push plate, 3-spring, 4-valve core, 5-second push plate, 6-nut, 7-flat washer, 8-spacer ring, 9-blocking, 10-sealing ring, 11-water outlet, 12-water hole, 13-water inlet. DETAILED DESCRIPTION

[0041] The following describes the embodiments of the present invention by 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 only illustrate the basic concept of the present invention in a schematic manner, and the following embodiments and features in the embodiments can be combined with each other without conflict.

[0042] Among them, the drawings are only used for illustrative explanations, and they only represent schematic diagrams rather than actual pictures, and should not be understood as limitations on the present invention. In order to better illustrate the embodiments of the present invention, some parts of the drawings may be omitted, enlarged or reduced, and do not represent the size of actual products. For those skilled in the art, it is understandable that some well-known structures and their descriptions in the drawings may be omitted.

[0043] 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 the terms "upper", "lower", "left", "right", "front", "rear", etc. indicate the orientation or position relationship, they are based on the orientation or position relationship shown in the drawings, which is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation. Therefore, the terms describing the position 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.

[0044] See also Figure 1 , is a drill barrel used in the jacking method in the prior art, and a through hole for inserting a steel bar is provided at one end of the drill barrel 1 away from the drill barrel opening; the operation method thereof during coring is as follows: a steel bar is inserted into the through hole at one end of the drill barrel 1 away from the drill barrel opening, so as to push the core out with the steel bar.

[0045] This method requires frequent disassembly of equipment, limited operating space, a high risk of secondary core breakage during the jacking process, and inability to achieve continuous operation.

[0046] Example 1

[0047] See also Figure 2 to Figure 4 , which is a water pressure core pushing device, including a drill tube 1, a first push plate 2, a spring 3, a valve core 4, a second push plate 5, a nut 6, a flat washer 7, a spacer ring 8 and a sealing component;

[0048] The structural connection relationship of each component is as follows

[0049] The drill barrel 1 is a hollow cylindrical structure, having an inner cavity for slidably installing the first push plate 2 along its axial direction and accommodating the core, and a water inlet 13 is provided at one end thereof for connecting the drilling mechanism, so as to allow cooling water to flow into the drill barrel 1;

[0050] The first push plate 2 is slidably installed in the inner cavity of the drill tube 1 along the axial direction of the drill tube 1, and is provided with a water outlet hole 11 that penetrates the first push plate 2 along the axial direction and a valve core installation cavity arranged radially. The valve core installation cavity is arranged on the side of the water outlet hole 11 away from the center of the first push plate 2, and is connected to the water outlet hole 11, and a valve core 4 and a spring 3 are built therein. The valve core 4 is a radially movable structure, and its initial position is preloaded by the spring 3, and is located in the water outlet hole 11, and is used to close the water outlet hole 11 with a diameter of A;

[0051] Furthermore, the spring 3 is arranged on a side of the valve core 4 away from the center of the first push plate 2, and a plug 9 is provided at one end of the valve core installation cavity away from the water outlet 11 to close the valve core installation cavity and fix one end of the spring 3.

[0052] The second push plate 5: The second push plate 5 is arranged on the side of the first push plate 2 away from the water inlet, and penetrates the first push plate 2 through a stud protruding in the middle thereof, and then is connected to the stud through a nut 6, and a flat washer 7 is provided between the nut 6 and the first push plate 2, so that the first push plate 2 and the second push plate 5 are rotatably connected with the stud as the axis, and a water hole 12 opposite to the water outlet 11 is provided on the second push plate 5, so that cooling water can flow out of the drill tube; in this embodiment, a retaining ring can be used to replace the nut 6 to realize the axial limiting function of the stud.

[0053] In another embodiment, the nut 6 can also lock the first push plate 2 and the second push plate 5 by connecting with the stud so that the first push plate 2 and the second push plate 5 are fixedly connected; or the first push plate 2 and the second push plate 5 are fixedly connected by methods such as welding.

[0054] Furthermore, a spacer ring 8 is provided between the second push plate 5 and the first push plate 2. Specifically, the spacer ring is a low-resistance spacer ring, which functions to reduce the resistance between the first push plate and the second push plate and to form a water-passing gap between the first push plate and the second push plate to prevent the second push plate 5 from blocking the water outlet hole 11 when the water hole 12 of the second push plate 5 is coaxially arranged with the water outlet hole 11.

[0055] The outer edge of the second push plate 5 is clearance-matched with the inner wall of the drill tube 1 to avoid direct frictional contact between the second push plate 5 and the drill tube 1 .

[0056] Sealing assembly: The sealing assembly is a sealing ring 10 arranged on the contact surface between the first push plate 2 and the drill tube to prevent cooling water from leaking from the contact surface between the first push plate 2 and the drill tube 1; the sealing ring 10 is embedded in the circumferential groove of the first push plate 2.

[0057] Furthermore, a cutter tooth is provided at one end of the drill tube 1 away from the water inlet 13, and the inner diameter of the cutter tooth is smaller than the inner diameter of the drill tube and the outer diameters of the first push plate 2 and the second push plate 5, so as to prevent the first push plate 2 from falling out of the drill tube during pushing the core. Specifically, the cutter tooth is connected to the drill tube 1 by welding or threading.

[0058] Furthermore, a hard alloy wear-resistant layer is inlaid on the surface of the second push plate 5, which is suitable for highly abrasive rock formations such as granite and quartzite.

[0059] Furthermore, in other embodiments, the spring 3 may be replaced by other elastic components having the same function, such as a rubber elastomer or an elastic gasket.

[0060] Example 2

[0061] like Figure 5 As shown, a control method of a hydraulic core pushing device is provided. One end of the hydraulic core pushing device provided with a water inlet is connected to a drilling mechanism, and the drill tube is driven to rotate by the drilling mechanism, and cooling water is introduced into the water inlet. The control method specifically includes the following steps:

[0062] Drilling stage ( Figure 2 ):

[0063] The second push plate 5 and the first push plate 2 stay at the cutter teeth, the drilling mechanism is started, the drill tube 1 rotates at high speed to drill downward, the rock forms a core in the drill tube 1, and pushes the second push plate 5 and the first push plate 2 to move axially toward one end of the water inlet;

[0064] Centrifugal force: The valve core 4 is subjected to centrifugal force to overcome the preload of the spring 3, and moves radially outward to open the water outlet with a diameter of A;

[0065] Water flow path: Cooling water is injected from the water inlet 13 at the top of the drill tube 1, and flows to the rock contact surface through the water outlet 11 opened by the valve core 4 and the water hole 12 of the second push plate 5, so as to achieve cooling, lubrication and debris flushing of the drill bit;

[0066] Anti-wear design: The second push plate 5 rotates relatively or synchronously with the first push plate 2 and directly contacts the rock to avoid the first push plate 2 from being worn out due to friction.

[0067] Core Pushing Stage Figure 3 ):

[0068] When the drill tube 1 drills to the designed depth, the drilling mechanism stops rotating, the centrifugal force of the valve core 4 disappears, and the spring 3 pushes the valve core 4 to return to its original position, closing the water outlet 11;

[0069] Water pressure energy storage: Continuous water injection forms a closed cavity between the drill tube 1 and the first push plate 2. After the water pressure gradually increases to a set threshold, the high-pressure water pushes the first push plate 2 to push out the core at a constant speed (such as 2-5MPa, the specific water pressure value is set according to actual needs);

[0070] Core pushing: Water pressure pushes the first push plate 2 and the second push plate 5 to move axially along the drill barrel 1, and the core is pushed out from the bottom of the drill barrel at a constant speed through mechanical linkage to prevent the core from breaking due to instantaneous impact force, and the drill barrel is simultaneously withdrawn from the borehole through the drilling mechanism connected to the drill barrel.

[0071] Reset: After the core is pushed, stop injecting water.

[0072] Furthermore, in the next drilling cycle, the first push plate 2 and the second push plate 5 are pushed toward one end of the drill tube close to the water inlet through the core.

[0073] A water pressure core pushing device is provided in this embodiment, which realizes automatic switching of water flow states between drilling and core pushing stages through the centrifugal movement of the valve core 4 without external control; the water flow is used for cooling and lubrication during drilling, and the water flow is closed to form high pressure during core pushing to avoid waste of water resources; and a second push plate 5 is provided to bear the friction effect to extend the service life of the first push plate 2.

[0074] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. 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 solution of the present invention can be modified or replaced by equivalents without departing from the purpose and scope of the technical solution, which should be included in the scope of the claims of the present invention.

Claims

1. A hydraulic core pushing device, characterized in that: include: The drill tube (1) is a hollow cylindrical structure, one end of which is provided with a water inlet (13) for introducing cooling water; A first push plate (2) is slidably installed in the inner cavity of the drill tube (1) along the axial direction of the drill tube (1), and the first push plate (2) is provided with an axially penetrating water outlet hole (11) and a radially arranged valve core installation cavity, wherein the valve core installation cavity is connected to the water outlet hole (11) and has a valve core (4) and an elastic component built therein; The valve core (4) is radially movable and installed in the valve core installation cavity, and is in an initial position under the action of the pre-tightening force of the elastic component to close the water outlet hole (11), and moves outward under the action of centrifugal force to open the water outlet hole (11).

2. The hydraulic core pushing device according to claim 1, characterized in that: Also includes: The second pushing plate (5) is arranged on a side of the first pushing plate (2) away from the water inlet (13), and the second pushing plate (5) is provided with a water hole (12).

3. The hydraulic core pushing device according to claim 2, characterized in that: The outer edge of the second push plate (5) is clearance-matched with the inner wall of the drill tube (1).

4. The hydraulic core pushing device according to claim 2, characterized in that: A spacer ring (8) is arranged between the first push plate (2) and the second push plate (5).

5. The hydraulic core pushing device according to claim 2, characterized in that: The elastic component is a spring (3).

6. The hydraulic core pushing device according to claim 2, characterized in that: A sealing component is provided on the contact surface between the first pusher plate (2) and the drill tube (1) to prevent cooling water leakage.

7. The hydraulic core pushing device according to claim 6, characterized in that: The sealing component is a sealing ring (10).

8. A control method for a hydraulic core pushing device, based on the device according to any one of claims 1 to 7, characterized in that: The following steps are involved: Drilling stage: The drill tube (1) is driven to rotate and drill, and the rock core pushes the first push plate (2) to move toward the water inlet (13); The valve core (4) overcomes the pre-tightening force of the elastic component under the action of centrifugal force, opens the water outlet hole (11), and the cooling water flows to the core contact surface through the water outlet hole (11); Core pushing stage: The rotation of the drill tube (1) is stopped, and the valve core (4) is reset to close the water outlet hole (11); Continuous water injection forms a closed cavity, and when the water pressure rises to a set threshold, the first push plate (2) is pushed out at a constant speed to push out the core and withdraw the drill tube from the borehole.

9. The control method according to claim 8, characterized in that: After the core pushing stage is completed, water injection is stopped and the first pusher plate (2) is pushed back to its original position by the next cycle of cores.

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