Pressure balanced ahead coring drill

Abstract

The application discloses a pressure balance ahead coring drill tool and relates to the field of geological drilling. The pressure balance ahead coring drill tool comprises a one-way mechanism, the bottom of the one-way mechanism is movably connected with a two-way circulation mechanism through threads, the surface of the two-way circulation mechanism is movably connected with a drill inner tube through threads, the bottom of the surface of the two-way circulation mechanism is movably connected with a drill outer tube through threads, the bottom of the drill inner tube is movably connected with an inner drill bit through threads, the bottom of the drill outer tube is movably connected with an outer drill bit through threads, the one-way mechanism comprises an upper joint, the inner cavity of the upper joint is provided with a valve seat, the bottom of the surface of the valve seat is sleeved with a first spring, and the two-way circulation mechanism comprises a double circulation joint. Through positive circulation of the gap between the inner tube and the outer tube and reverse circulation of the inner tube, the pressure balance ahead coring drill tool can realize optimization of a drill flow channel, pressure balance, and prevention of the situation that, in the process of brine mineral exploration drilling, a mine layer contains ore due to serious mud making, thereby causing a drill jam and the like, so that the problems in the background art are solved.

Description

Technical Field

[0001] This invention relates to the field of geological drilling, specifically to a pressure-balanced advanced coring tool. Background Technology

[0002] Currently, in the exploration process of brine mines, it is necessary to drill and sample the ore-bearing strata to provide physical data and geological information for the investigation and evaluation of mineral resources. Therefore, it is necessary to use drilling tools to sample the ore-bearing strata.

[0003] Currently, commonly used drilling tools for brine mineral exploration and sampling include single-tube drilling tools, ordinary double-tube drilling tools, and wireline coring tools. These tools obtain ore samples by drilling into the ore layer. However, existing drilling tools are all designed with a positive circulation channel, resulting in an imbalance of pressure inside and outside the drilling tool during drilling. Conventional wireline coring tools and double-tube drilling tools are prone to problems such as drill blockage and pressure buildup, leading to drilling difficulties and making them unsuitable for formations with severe slurry formations. Wireline coring drill rods are not interchangeable with reaming drill rods, resulting in high construction costs and hindering their use.

[0004] To address the above problems, this invention provides a pressure-balanced advanced coring tool. Summary of the Invention

[0005] The purpose of this invention is to provide a pressure-balanced advanced coring drill bit. By optimizing the flow channel and balancing the pressure of the drill bit through positive circulation of the inner and outer tube annular gap and reverse circulation of the inner tube, the drilling bit can be optimized and the drilling can be balanced. This prevents situations such as drill blockage caused by severe mud making in the ore-bearing layer during brine mineral exploration drilling, thereby solving the problems in the background art.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a pressure-balanced advanced coring drill bit, comprising a one-way mechanism, the bottom of which is threadedly connected to a two-way circulation mechanism, the surface of which is threadedly connected to an inner tube, the bottom of which is threadedly connected to an outer tube, the bottom of which is threadedly connected to an inner drill bit, the bottom of which is threadedly connected to an outer drill bit, the one-way mechanism comprising an upper connector, the inner cavity of which is provided with a valve seat, the bottom of which is fitted with a first spring, the two-way circulation mechanism comprising a double circulation connector, the bottom of which is provided with a valve groove, the front and rear sides of which are provided with reverse circulation channels, the bottom of which are provided with positive circulation channels, the bottom of which is threadedly connected to a valve cap, the top of which is provided with a steel ball, and the inner cavity of which is provided with a sample negative pressure fixing mechanism.

[0007] Furthermore, the sample negative pressure fixing mechanism includes a piston plate, a through hole at the bottom of the piston plate, a positioning shell fixedly connected to the top of the piston plate, a positioning frame fixedly connected between the two sides of the inner cavity of the positioning shell, a limit rod at the top of the positioning frame, a second spring sleeved through the bottom of the limit rod, and a sealing plate fixedly connected to the bottom of the limit rod.

[0008] Furthermore, a limiting block is fixedly connected to the top of the limiting rod, a rubber pad is fixedly connected to the bottom of the sealing plate, and a sealing ring is fitted on the surface of the piston plate.

[0009] Furthermore, the top of the positioning frame is provided with an opening for use with the limiting rod, and the inner wall of the drill bit outer tube is provided with a sliding groove for use with the piston plate.

[0010] Furthermore, an anti-wear ring is fitted onto the surface of the upper connector, and the surface of the valve seat is fixedly connected to the first spring.

[0011] Furthermore, a rubber sealing ring is fixedly connected to the top of the valve cover, and a retaining ring is fixedly connected to the bottom of the valve cover.

[0012] Furthermore, the inner wall of the upper connector is provided with a tapered inclined surface that cooperates with the valve seat, and the outer drill bit is located at the bottom of the inner drill bit.

[0013] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0014] 1. The present invention provides a pressure-balanced advanced coring drill bit, which, through a sample negative pressure fixing mechanism, can create a negative pressure state inside the drill bit after the rock core enters the inner tube, firmly adsorbing the rock core inside, thereby preventing the rock core from falling off due to gravity.

[0015] 2. Through the design of positive and negative circulation channels, during drilling and drilling with drilling fluid circulation, the top of the inner tube of the drill bit is directly connected to the annular channel between the outer tube of the drill bit and the borehole wall. The annular channel between the outer tube of the drill bit and the inner tube of the drill bit is connected to the bottom of the hole through the drill bit, thereby ensuring that the inside of the drill bit is connected to the bottom of the hole and avoiding pressure buildup or drill blockage.

[0016] 3. Through the design of the one-way mechanism, during drilling and drilling without drilling fluid circulation, the valve seat closes under the pressure of the first spring, and the annular channel between the inner tube and the outer tube of the drill bit is closed, preventing mud and sand from entering the hole and causing blockage.

[0017] 4. Through the advanced core sampling structure design, during drilling with drilling fluid circulation, the drilling fluid enters the annular channel between the outer tube of the drill string and the borehole wall through the annular channel between the inner tube and the outer tube of the drill string, thus avoiding disturbing the core. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of the present invention;

[0019] Figure 2 This is a cross-sectional view of the structure of the present invention;

[0020] Figure 3 This is a side sectional view of the dual-loop connector of the present invention;

[0021] Figure 4 This is an exploded view of the negative pressure fixing mechanism for samples according to the present invention.

[0022] In the diagram: 1. One-way mechanism; 2. Two-way circulation mechanism; 3. Drill tool inner tube; 4. Drill tool outer tube; 5. Inner drill bit; 6. Outer drill bit; 101. Upper connector; 102. Valve seat; 103. First spring; 201. Double circulation connector; 202. Valve groove; 203. Reverse circulation channel; 204. Positive circulation channel; 205. Valve gland; 206. Steel ball; 7. Sample negative pressure fixing mechanism; 701. Piston plate; 702. Through hole; 703. Positioning shell; 704. Positioning frame; 705. Limiting rod; 706. Second spring; 707. Sealing plate; 708. Rubber pad; 8. Anti-wear ring. Detailed Implementation

[0023] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0024] To address the technical problems of drill string blockage and pressure buildup caused by pressure imbalance inside and outside the drill string during drilling, and the resulting drilling difficulties, such as... Figure 1-4 As shown, the following preferred technical solutions are provided:

[0025] A pressure-balanced advanced coring drill bit includes a one-way mechanism 1. The bottom of the one-way mechanism 1 is threadedly connected to a two-way circulation mechanism 2. The surface of the two-way circulation mechanism 2 is threadedly connected to an inner drill tube 3. The bottom of the surface of the two-way circulation mechanism 2 is threadedly connected to an outer drill tube 4. The bottom of the inner drill tube 3 is threadedly connected to an inner drill bit 5, and the bottom of the outer drill tube 4 is threadedly connected to an outer drill bit 6. The one-way mechanism 1 includes an upper connector 101, and the inner cavity of the upper connector 101 is provided with a valve seat 102. A first spring 103 is fitted on the bottom of the surface 102. The bidirectional circulation mechanism 2 includes a double circulation joint 201. A valve groove 202 is opened at the bottom of the double circulation joint 201. A reverse circulation channel 203 is opened on the front and rear sides of the inner cavity of the valve groove 202. A positive circulation channel 204 is opened at the bottom of both sides of the inner cavity of the double circulation joint 201. A valve cover 205 is connected to the bottom of the inner cavity of the valve groove 202 by a thread. A steel ball 206 is set on the top of the valve cover 205. A sample negative pressure fixing mechanism 7 is set in the inner cavity of the drill outer tube 4.

[0026] The sample negative pressure fixing mechanism 7 includes a piston plate 701, a through hole 702 at the bottom of the piston plate 701, a positioning shell 703 fixedly connected to the top of the piston plate 701, a positioning frame 704 fixedly connected between the two sides of the inner cavity of the positioning shell 703, a limit rod 705 provided at the top of the positioning frame 704, a second spring 706 sleeved at the bottom of the limit rod 705 through the positioning frame 704, and a sealing plate 707 fixedly connected to the bottom of the limit rod 705.

[0027] A limit block is fixedly connected to the top of the limit rod 705, a rubber pad 708 is fixedly connected to the bottom of the sealing plate 707, and a sealing ring is fitted on the surface of the piston plate 701.

[0028] The top of the positioning frame 704 has an opening for use with the limiting rod 705, and the inner wall of the drill string outer tube 4 has a sliding groove for use with the piston plate 701.

[0029] Specifically, the sample negative pressure fixing mechanism 7 creates a negative pressure state inside the drill string inner tube 3 after the core sample enters it, firmly adhering the core sample inside and preventing it from falling out due to gravity. Through the design of the positive circulation channel 204 and the reverse circulation channel 203, during drilling and drilling with drilling fluid circulation, the top of the drill string inner tube 3 directly connects to the annular channel between the drill string outer tube 4 and the borehole wall. The annular channel between the drill string outer tube 4 and the drill string inner tube 3 connects to the bottom of the borehole through the drill bit, thus ensuring the internal structure of the drill string is aligned with the borehole wall. The bottom of the hole is connected to prevent pressure buildup or drill blockage. Through the design of the one-way mechanism 1, during drilling and drilling without drilling fluid circulation, the valve seat 102 closes under the pressure of the first spring 103, and the annular channel between the inner tube 3 and the outer tube 4 of the drill bit is closed accordingly, preventing mud and sand from entering the hole and causing blockage. Through the advanced core sampling structure design, during drilling with drilling fluid circulation, the drilling fluid enters the annular channel between the outer tube 4 and the hole wall through the annular channel between the inner tube 3 and the outer tube 4 of the drill bit, avoiding disturbance of the core.

[0030] To solve the technical problems of poor sealing between valve gland 205 and steel ball 206 and difficulty in removal, such as Figure 2 and Figure 3 As shown, the following preferred technical solutions are provided:

[0031] The surface of the upper connector 101 is fitted with an anti-wear ring 8, and the surface of the valve seat 102 is fixedly connected to the first spring 103.

[0032] A rubber sealing ring is fixedly connected to the top of the valve cover 205, and a retaining ring is fixedly connected to the bottom of the valve cover 205.

[0033] Specifically, the rubber sealing ring can improve the sealing effect between the valve cover 205 and the steel ball 206, and the retaining ring can facilitate the user to disassemble the valve cover 205.

[0034] To address the technical problem of poor sealing between the valve seat 102 and the inner wall of the upper connector 101, allowing mud and sand to easily enter the upper connector 101, such as... Figure 2 As shown, the following preferred technical solutions are provided:

[0035] The inner wall of the upper connector 101 is provided with a tapered inclined surface that mates with the valve seat 102, and the outer drill bit 6 is located at the bottom of the inner drill bit 5.

[0036] Specifically, the tapered inclined surface can fit against the inclined surface at the top of the valve seat 102 and cooperate with the first spring 103 to make the two fit tightly against each other, thereby improving the sealing effect of the valve seat 102.

[0037] Working Principle: During use, the drill pipe is fixed to the top of the upper connector 101 via a female threaded connection. During drilling, the drilling fluid comes into contact with the valve seat 102 through the internal channel of the upper connector 101. The pressure of the drilling fluid squeezes the valve seat 102, causing it to move downwards and compress the first spring 103. When the top of the valve seat 102 no longer contacts the conical inclined surface, the drilling fluid enters the double circulation connector 201, thus forming a unidirectional flow channel. After entering the double circulation connector 201, the drilling fluid enters the space between the inner tube 3 and the outer tube 4 of the drill string through the positive circulation channel 204, cooling the inner drill bit 5 and the outer drill bit 6 and transmitting hydraulic power. During the drilling process, the drilling fluid in the inner tube 3... The drilling fluid flows upward, passing through the piston plate 701 and valve cover 205 before flowing into the valve groove 202 and pushing the steel ball 206. The steel ball 206 moves upward to open the channel, and the drilling fluid flows out of the drill string after passing through the reverse circulation channel 203, thus ensuring that the inside of the drill string is connected to the bottom of the hole, balancing the pressure, and avoiding pressure buildup or drill blockage. After the core enters the inner tube 3 of the drill string, the core moves upward to squeeze the piston plate 701. The air between the core and the piston plate 701 squeezes the sealing plate 707 through the through hole 702, causing the sealing plate 707 to move upward to squeeze the second spring 706. After the air between the core and the piston plate 701 is discharged, a negative pressure state is formed between the two, which firmly adsorbs the core in the inner tube 3 of the drill string, effectively preventing the core from falling out.

[0038] In summary, this pressure-balanced advanced coring drill bit, through the coordinated use of the inner tube 3, outer tube 4, inner drill bit 5, outer drill bit 6, upper connector 101, valve seat 102, first spring 103, double circulation connector 201, valve groove 202, reverse circulation channel 203, forward circulation channel 204, valve cover 205, and steel ball 206, solves the problems of drill blockage, pressure buildup, and drilling difficulties caused by the pressure imbalance inside and outside the drill bit during drilling.

[0039] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0040] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A pressure balanced ahead coring drill tool comprising a one-way mechanism (1), characterized in that: The bottom of the one-way mechanism (1) is connected to the two-way circulation mechanism (2) by a threaded connection. The surface of the two-way circulation mechanism (2) is connected to the drill inner tube (3) by a threaded connection. The bottom of the surface of the two-way circulation mechanism (2) is connected to the drill outer tube (4) by a threaded connection. The bottom of the drill inner tube (3) is connected to the inner drill bit (5) by a threaded connection. The bottom of the drill outer tube (4) is connected to the outer drill bit (6) by a threaded connection. The one-way mechanism (1) includes an upper connector (101). The inner cavity of the upper connector (101) is provided with a valve seat (102). The bottom of the surface of the valve seat (102) is sleeved with... The bidirectional circulation mechanism (2) includes a first spring (103), a double circulation joint (201), a valve groove (202) is provided at the bottom of the double circulation joint (201), a reverse circulation channel (203) is provided on the front and rear sides of the inner cavity of the valve groove (202), a positive circulation channel (204) is provided at the bottom of both sides of the inner cavity of the double circulation joint (201), a valve cover (205) is connected to the bottom of the inner cavity of the valve groove (202) by a thread, a steel ball (206) is provided on the top of the valve cover (205), and a sample negative pressure fixing mechanism (7) is provided in the inner cavity of the drill outer tube (4). The sample negative pressure fixing mechanism (7) includes a piston plate (701) and a rubber pad (708) that can seal the piston plate. The inner wall of the drill outer tube (4) is provided with a sliding groove that cooperates with the piston plate (701).

2. The pressure-balanced lead coring tool according to claim 1, characterized in that: The piston plate (701) has a through hole (702) at the bottom. A positioning shell (703) is fixedly connected to the top of the piston plate (701). A positioning frame (704) is fixedly connected between the two sides of the inner cavity of the positioning shell (703). A limit rod (705) is provided at the top of the positioning frame (704). The bottom of the limit rod (705) passes through the positioning frame (704) and is fitted with a second spring (706). A sealing plate (707) is fixedly connected to the bottom of the limit rod (705).

3. The pressure-balanced lead coring tool according to claim 2, characterized in that: The top of the limiting rod (705) is fixedly connected to a limiting block, the bottom of the sealing plate (707) is fixedly connected to a rubber pad (708), and the surface of the piston plate (701) is fitted with a sealing ring.

4. The pressure-balanced lead coring tool according to claim 2, characterized in that: The top of the positioning frame (704) has an opening that works in conjunction with the limiting rod (705).

5. The pressure-balanced lead coring tool according to claim 1, characterized in that: The surface of the upper connector (101) is fitted with an anti-wear ring (8), and the surface of the valve seat (102) is fixedly connected to the first spring (103).

6. The pressure-balanced lead coring tool according to claim 1, characterized in that: A rubber sealing ring is fixedly connected to the top of the valve cover (205), and a retaining ring is fixedly connected to the bottom of the valve cover (205).

7. The pressure-balanced lead coring tool according to claim 1, characterized in that: The inner wall of the upper connector (101) is provided with a tapered inclined surface that cooperates with the valve seat (102), and the outer drill bit (6) is located at the bottom of the inner drill bit (5).

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