A water jet type high-low pressure conversion coal seam slotting device

Abstract

This utility model discloses a water jet type high-low pressure conversion coal seam slotting device, including a male head shell, a female head shell, and a nozzle. The joint between the male and female head shells is set as cavity one. The threaded connection of the female head shell is installed with the drill rod. The nozzles are symmetrically threaded on both sides of the outer side of cavity two. A channel two is opened inside the nozzle. A negative pressure valve block is threaded on the side of cavity two near cavity one. The side of the negative pressure valve block near cavity one is opened as channel one. This solves the technical problem that the front section and nozzle of the water jet type high-low pressure conversion coal seam slotting device will simultaneously emit water during drilling. It realizes that the front end of the water jet type high-low pressure conversion coal seam slotting device emits water during drilling. Due to the negative pressure principle, the nozzle is in a closed state. During the cutting process, the front section is closed, and the nozzle is in a water jet state. The valve core can overcome the pressure of the return spring, and the water flow pushes the valve core and flows out from the jet hole, realizing the drilling operation state.

Description

Technical Field

[0001] This utility model relates to the field of coal seam slotting technology, specifically to a water jet type high-low pressure conversion coal seam slotting device. Background Technology

[0002] To improve the gas extraction efficiency of low-permeability coal seams, high-pressure water jets are used to cut slots in the gas extraction boreholes. High-pressure water jet cutting alters the original stress and fracture conditions of the coal seam, improving gas flow and increasing gas extraction efficiency. However, existing water jet coal seam cutting devices require flaring. During drilling, cooling water flows through the high-low pressure conversion water jet coal seam cutting device, with water exiting from both the front section and the nozzle simultaneously. This reduces the water flow through the drill bit, decreasing its cooling effect and reducing dust removal capacity during drilling.

[0003] Therefore, a water jet type high-low pressure conversion coal seam slotting device is needed. Utility Model Content

[0004] To address the problems existing in the prior art, this utility model provides a water jet type high-low pressure conversion coal seam slotting device. In order to overcome the above-mentioned technical shortcomings, the purpose is to achieve that during the drilling process, the water jet type high-low pressure conversion coal seam slotting device has water exiting at the front end and the nozzle closed; during the slotting process, the front section is closed and the nozzle is in the water jet state.

[0005] To achieve the above objectives, this utility model provides the following technical solution: a water jet type high-low pressure conversion coal seam slotting device, comprising a male head shell, a female head shell, and nozzles. The joint between the male and female head shells is configured as cavity one. The threaded connection of the female head shell is installed with a drill rod. A filter plate is provided between cavity one and the threaded connection. One side of the male head shell is configured as cavity two, and the other side is configured as an outflow channel. Nozzles are symmetrically threaded on both sides of the exterior of cavity two. A channel two is opened inside the nozzles. A negative pressure valve block is threaded on the side of cavity two closest to cavity one, and a... The valve core housing is set up with a channel 1 on one side of the negative pressure valve block near the cavity 1 and a channel 3 on the other side. The nozzle is further threaded into the channel 3. The channel 2 is connected to the channel 3. The valve core housing contains a valve core. A return spring is sleeved on the side of the valve core away from the channel 3. The return spring is installed between the valve core and the inner wall of the valve core housing. The valve core has a jet hole in its circumference so that the fluid flows from the channel 3 through the jet hole to the valve core housing. In the initial state of the valve core or during the cutting operation, due to the pressure of the return spring, the valve core abuts against the negative pressure valve block and the jet hole is closed.

[0006] Preferably, the outside of the outflow channel is configured with a threaded layer, and a filter plate 2 is provided at the outlet end of the outflow channel.

[0007] Preferably, the side of channel two closest to channel three is configured as a funnel-shaped channel, and the smaller diameter end of the funnel-shaped channel continues to extend outward to form a slender channel segment of channel two.

[0008] Preferably, the axial length of channel one is at least twice its inner diameter.

[0009] Preferably, the inner diameter of channel one is smaller than the inner diameter of channel three.

[0010] Preferably, the nozzles are symmetrically arranged along the axis of the male head housing, and the number is set to two. The nozzles pass through the male head housing and the negative pressure valve block in sequence to realize the connection between channel two and channel three.

[0011] In summary, this utility model provides a water jet type high-low pressure conversion coal seam slotting device. This utility model patent achieves this by regulating the water pressure and flow rate: during drilling operations, the interior of channel three is under negative pressure, allowing high-pressure gas from the outside to quickly pass through the funnel-shaped structure. The external gas flows into the interior of channel three, and the water inside channel three does not flow out due to the negative pressure. This solves the technical problem that the front section and nozzle of the water jet type high-low pressure conversion coal seam slotting device will simultaneously emit water during drilling. It realizes that during drilling, the front end of the water jet type high-low pressure conversion coal seam slotting device emits water, and due to the negative pressure principle, the nozzle is in a closed state; during slotting, the front section is closed, and the nozzle is in a water jet state.

[0012] When slit cutting is required, the flow rate and pressure of the delivered water can be reduced. Due to the pressure of the return spring, the valve core inlet side contacts and closes with the valve core housing. At this time, the delivered water is jetted out from the nozzle channel, allowing slit cutting to be performed. When the water pressure and flow rate are increased, the valve core can overcome the pressure of the return spring, and the water flow lifts the valve core, flowing out from the jet hole, thus achieving drilling operation. Attached Figure Description

[0013] Fig. 1 This is a schematic diagram of the overall structure of the water jet type high-low pressure conversion coal seam slotting device of this utility model;

[0014] Fig. 2 This is a schematic diagram of the internal cross-sectional structure of the water jet type high-low pressure conversion coal seam slotting device of this utility model;

[0015] Fig. 3 This is a cross-sectional schematic diagram of the structure of the valve core of this utility model installed between the valve core housing and the negative pressure valve block;

[0016] In the diagram: male head housing 1, cavity 2 11, outflow channel 12, filter plate 2 13, valve core housing 2, return spring 3, valve core 4, nozzle 5, valve core 4, jet hole 41, channel 2 51, negative pressure valve block 6, channel 1 61, channel 3 62, female head housing 7, cavity 1 71, filter plate 1 72. Detailed Implementation

[0017] The present invention will be further described below with reference to the accompanying drawings.

[0018] like Figs. 1 to 3 As shown:

[0019] This utility model is a water jet type high-low pressure conversion coal seam slotting device. In order to solve the problem of the existing water jet coal seam slotting device, when the cooling water flows through the inside of the water jet type high-low pressure conversion coal seam slotting device during the drilling process, the front section and the nozzle will simultaneously discharge water, which will reduce the amount of water passing through the front drill bit, thereby reducing the cooling effect of the drill bit and the powder removal capacity during the drilling operation.

[0020] The technical solution adopted in this patent is as follows: It includes a male head housing 1, a female head housing 7, and a nozzle 5. The joint between the male head housing 1 and the female head housing 7 is configured as cavity 1 71. The threaded connection of the female head housing 7 is installed with the drill rod. A filter plate 72 is installed between cavity 1 71 and the threaded connection. One side of the interior of the male head housing 1 is configured as cavity 2 11, and the other side is configured as an outflow channel 12. The nozzles 5 are symmetrically threaded on both sides of the exterior of cavity 2 11. A channel 2 51 is opened inside the nozzles 5. A negative pressure valve block 6 is threaded on the side of cavity 2 11 closest to cavity 1 71, and the other side is configured as a valve core housing 2. A channel is opened inside the negative pressure valve block 6 on the side closest to cavity 1 71. 1. On the other side, a channel 3 62 is opened. The nozzle 5 continues to be threaded into the channel 3 62. The channel 2 51 is connected to the channel 3 62. The valve core 4 is installed inside the valve core housing 2. The return spring 3 is sleeved on the side of the valve core 4 away from the channel 3 62. The return spring 3 is installed between the inner wall of the valve core housing 2 and the valve core 4. The valve core 4 has a jet hole 41 in its circumference so that the fluid flows from the channel 3 62 through the jet hole 41 to the valve core housing 2. The valve core housing 2 is connected to the outflow channel 12 so that the fluid flows out. In the initial state or during the cutting operation, due to the pressure of the return spring 3, the valve core 4 abuts against the negative pressure valve block 6 and the jet hole 41 is closed.

[0021] The specific operating principle is as follows: During drilling operations, water is transported from the drill rod to the cavity 71 of the cutting device, and then enters the channel 61 inside the negative pressure valve block 6. The axial length of the channel 61 is more than twice its inner diameter. Thus, when the fluid reaches the channel 62 through the channel 61, it forms a high-speed fluid. According to Bernoulli's principle, the pressure inside the channel 62 decreases due to the high-speed movement of the fluid, creating a negative pressure state. The fluid inside the channel 62 will not flow out of the channel 51 inside the nozzle 5. Due to the pressure of the high-speed fluid, it will press against the valve core 4, offsetting the pressure of the return spring 3 on the valve core 4. All the high-speed fluid will reach the valve core housing 2 through the jet hole 41 on the valve core 4, and then flow out through the outflow channel 12 of the water jet type high-low pressure conversion coal seam cutting device. Since the diameter of the channel 61 is small, it can play a role in adjusting the closing pressure of the valve core of the water jet type high-low pressure conversion coal seam cutting device. Therefore, its size can be determined by the high-low pressure switching pressure of the cutting device.

[0022] When slit cutting is required, the flow rate and pressure of the delivered water can be reduced. Due to the pressure of the return spring 3, the valve core 4's inlet side contacts and closes with the valve core housing 2. At this time, the delivered water is ejected from the nozzle 5 through channel 2 51, allowing slit cutting to be performed. When the delivered water pressure and flow rate increase, the valve core 4 can overcome the pressure of the return spring 3, and the water flow lifts the valve core 4, flowing out from the jet hole 41, thus achieving a drilling operation state.

[0023] In at least one embodiment, the outside of the outflow channel 12 is configured as a threaded layer, and a filter plate 2 13 is provided at the outlet end of the outflow channel 12 to achieve water filtration and successfully complete the drilling operation.

[0024] In at least one embodiment, the side of channel 2 51 near channel 3 62 is configured as a funnel-shaped channel, and the smaller diameter end of the funnel-shaped channel continues to extend outward to form a long and narrow channel segment of channel 2 51.

[0025] Specifically, during drilling operations, the interior of channel 3 62 is under negative pressure. To further enhance the pressure inside channel 2 51 from the outside in, a slender channel structure is used at the end in contact with the outside, and a funnel-shaped structure is used at the end in contact with channel 3 62. This allows high-pressure gas from the outside to quickly pass through the funnel-shaped structure and flow into the interior of channel 3 62. Due to the negative pressure, the water inside channel 3 62 does not flow outward. This solves the technical problem of water exiting from the front section and nozzle simultaneously inside the water jet type high-low pressure conversion coal seam slotting device. It enables the water jet type high-low pressure conversion coal seam slotting device to exit water at the front end during drilling, while the nozzle is in a closed state due to the negative pressure principle; during the slotting process, the front section is closed, and the nozzle is in a water jet state.

[0026] In at least one embodiment, the inner diameter of channel 1 61 is smaller than that of channel 3 62, so that high-speed water flows to channel 3 62. During the drilling operation, a negative pressure state is formed in channel 3 62 to prevent water from being ejected through channel 2 51 of nozzle 5. During the slit cutting operation, the flow rate and pressure of the delivered water are reduced, and the water flows out through channel 2 51 of nozzle 5, at which time the slit cutting operation can be carried out.

[0027] In at least one embodiment, to enable the switching between drilling and slitting operations, the flow rate and pressure of the water supply are adjusted to meet the switching requirements. The structure is as follows: two nozzles 5 are symmetrically arranged along the axis of the male housing 1, and the nozzles 5 sequentially penetrate the male housing 1 and the negative pressure valve block 6 to connect channel 2 51 and channel 3 62. Under high-speed water pressure, channel 3 62 forms a negative pressure state, preventing water from flowing out through the nozzles 5. During slitting operations, the flow rate and pressure of the water supply are reduced, and the water flows out through the nozzles 5. The inlet side of the valve core 4 contacts and closes with the valve core housing 2, allowing slitting operations to be performed.

[0028] The embodiments described in this utility model are for illustrative purposes only and do not constitute a limitation on the scope of the claims. Other substantially equivalent substitutions that can be conceived by those skilled in the art are all within the protection scope of this utility model.

Claims

1. A water jet type high-low pressure conversion coal seam slotting device, characterized in that, The system includes a male head housing (1), a female head housing (7), and a nozzle (5). The joint between the male head housing (1) and the female head housing (7) is set as cavity one (71). The threaded connection of the female head housing (7) is installed with the drill rod. A filter plate one (72) is set between cavity one (71) and the threaded connection. One side of the interior of the male head housing (1) is set as cavity two (11), and the other side is set as an outlet channel (12). The nozzles (5) are symmetrically threaded on both sides of the exterior of cavity two (11). A channel two (51) is opened inside the nozzles (5). A negative pressure valve block (6) is threaded on the side of cavity two (11) near cavity one (71), and the other side is set as a valve core housing (2). A passage is opened on the side of the negative pressure valve block (6) near cavity one (71). Channel 1 (61) is opened on the other side as Channel 3 (62). The nozzle (5) continues to be threaded into the inside of Channel 3 (62). Channel 2 (51) is connected to Channel 3 (62). The valve core housing (2) is equipped with a valve core (4). A reset spring (3) is sleeved on the side of the valve core (4) away from Channel 3 (62). The reset spring (3) is installed between the inner wall of the valve core housing (2) and the valve core (4). The valve core (4) has a jet hole (41) in its circumference so that the fluid flows from Channel 3 (62) through the jet hole (41) to the valve core housing (2). In the initial state or during the cutting operation, due to the pressure of the reset spring (3), the valve core (4) abuts against the negative pressure valve block (6) and the jet hole (41) forms a closed state.

2. The water jet type high-low pressure conversion coal seam slotting device according to claim 1, characterized in that, The outside of the outflow channel (12) is set with a threaded layer, and a filter plate (13) is provided at the outlet end of the outflow channel (12).

3. The water jet type high-low pressure conversion coal seam slotting device according to claim 1, characterized in that, The side of channel 2 (51) near channel 3 (62) is set in the shape of a trumpet mouth, and the smaller diameter end of the trumpet mouth continues to extend outward to form the slender channel section of channel 2 (51).

4. The water jet type high-low pressure conversion coal seam slotting device according to claim 1, characterized in that, The axial length dimension of channel one (61) is at least twice its inner diameter dimension.

5. A water jet type high-low pressure conversion coal seam slotting device according to claim 4, characterized in that, The inner diameter of channel one (61) is smaller than that of channel three (62).

6. A water jet type high-low pressure conversion coal seam slotting device according to claim 1, characterized in that, The nozzles (5) are symmetrically arranged along the axis of the male head housing (1), and the number is set to two. The nozzles (5) pass through the male head housing (1) and the negative pressure valve block (6) in sequence to realize the connection between channel two (51) and channel three (62).

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