Pressure self-balancing superhigh pressure sealed water braid

Abstract

A pressure self-balancing superhigh pressure sealing water braid comprises a mandrel, a water braid shell, a gland, a pressing wire, a transition pressure disc, a rotating bearing and a thrust ball bearing. The mandrel is arranged inside the water braid shell through the gland, the bearing, the transition pressure disc and the pressing wire. The rotating bearing is arranged on both sides of the shoulder of the mandrel to support the mandrel inside the water braid shell. The transition pressure disc is arranged between the rotating bearing and the thrust ball bearing to change the force direction of the two bearings from radial to axial. The gland is arranged at the right end of the water braid shell. Sealing elements are arranged between the end cover and the mandrel and between the end cover and the water braid shell. The water hole in the mandrel is communicated with the water braid shell. A high pressure sealing element is arranged at the left end of the water braid shell to isolate the high pressure water in the mandrel and the water braid. The left end of the water braid shell is provided with a thread matched with the drill rod. The water braid can be connected with the drill rod and rotates with the drill rod while the mandrel is fixed. The water braid can bear a large pressure and has the advantages of convenient connection, wear resistance and good sealing performance.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of coal mine gas control, especially to the technical field of high-pressure water cutting and punching in a borehole. BACKGROUND

[0002] In the process of coal mining, a large amount of gas is often contained in the coal seam, so measures need to be taken to reduce the gas content of the coal seam before mining to eliminate its danger. Generally, a drilling machine is used to drill a borehole in the coal seam, and gas is extracted through negative pressure. After the gas pressure and content meet the standards, the coal seam can be mined. Due to the poor permeability of the coal seam in China, the influence radius of a single extraction hole is small and difficult to meet the requirements; only relying on automatic release of gas has low efficiency; and it is difficult to meet the production needs. In order to improve the gas extraction efficiency, the most effective method at present is to use high-pressure water jet to cut or punch the coal seam after drilling, thereby expanding the actual influence range of the borehole twice, increasing the borehole radius, and improving the extraction efficiency. Therefore, the drill rod used for drilling needs to be directly used for punching and cutting, and high-pressure water flows through the inside of the drill rod during punching and cutting. In order to ensure that the high-pressure hose successfully enters the continuously rotating drill rod, higher requirements are placed on the water braid at the tail of the drill rod. The water braid not only needs to withstand high pressure of more than 30MPA, but also needs to be dynamically sealed in a rotating state. In addition, the water braid needs to ensure smooth rotation under the premise of ensuring sealing, prevent water from entering the inside of the water braid, prevent internal components from rusting, and require long service life of the sealing element. Due to the large internal pressure, the internal structure must be reasonably stressed to prevent friction between components. SUMMARY

[0003] The pressure self-balancing super-high-pressure sealed water braid has the advantages of high pressure resistance, good sealing, flexible and reliable rotation, long service life, and the like.

[0004] The application is characterized in that the left side of the pressure self-balancing superhigh-pressure sealing water braid shell is provided with threads matched with the drill rod and connected with the drill rod, and the right side of the shell is connected with a high-pressure rubber pipe; the water braid shell, the pressure wire, the mandrel, the transition pressure disc and the gland are connected concentrically from left to right; the right side of the mandrel is connected with the high-pressure rubber pipe; the water braid shell is connected with the high-pressure sealing drill rod; the mandrel penetrates through the pressure wire, the transition pressure disc and the gland and goes deep into the water braid shell; the mandrel and the water braid shell are relatively connected in rotation; the gland is connected with the water braid shell through bolts; the gland is provided with a first sealing groove and a second sealing groove; the right side hole of the water braid shell is provided with a sealing chamfer surface matched with the second sealing groove of the gland; the first sealing groove and the second sealing groove are both provided with sealing elements; a high-pressure combined sealing element is arranged between the inner hole of the mandrel and the water braid shell; the pressure wire is provided with external threads; the inner hole of the water braid shell is provided with external threads; the high-pressure sealing element is fixed in the water braid shell through the threads of the pressure wire; the shaft shoulder of the mandrel is provided with rotary bearings on the left and right sides; the inner rings of the two bearings are both supported on the two sides of the shaft shoulder; the outer ring of the left bearing is supported on the left side of the inner hole of the water braid shell; the inner ring of the right bearing is supported on the small-diameter side of the transition pressure disc; the large-diameter side of the transition pressure disc is supported on the tight side of the thrust ball bearing; the loose side of the thrust ball bearing is connected with the gland fixed on the water braid shell; the mandrel is provided with a water passing hole; the water braid shell is provided with a water passing hole; the water passing hole of the mandrel is connected with the water passing hole of the water braid shell; the outer circle of the water braid shell is milled with a clamping plane to facilitate the clamping of the water braid dismounting tool.

[0005] Further, the connection mode of the right side of the mandrel and the high-pressure rubber pipe is the quick plug connector commonly used in coal mines.

[0006] Further, the gland is fixed on the water braid shell through bolts, and the gland is provided with a first sealing groove and a second sealing groove; the right side hole of the water braid shell is provided with a sealing chamfer surface matched with the second sealing groove of the gland, and the sealing chamfer surface plays a sealing role in the gaps between the mandrel and the gland and between the gland and the water braid shell.

[0007] Further, the inside of the water braid shell is filled with lubricating oil, which plays a lubricating and anti-rust role, can balance the high-pressure water pressure received by the front-end sealing ring, and also has the functions of lubricating the sealing ring and preventing high-pressure water from entering the water braid.

[0008] Further, the bearings inside the water braid shell are a combination of radial force bearings and axial force bearings, the radial force bearings for supporting are two deep groove ball bearings, and the axial force bearing is a thrust ball bearing.

[0009] Further, a transition pressure disc is arranged between the two different bearings.

[0010] Further, a high-pressure combined sealing element is arranged between the left side of the mandrel and the water passing hole of the water braid, and the high-pressure combined sealing element is fixed in the water braid shell through the thread connection between the pressure wire and the inner thread of the water braid shell.

[0011] Further, the arrangement of the drill pipe, the water braid shell, the mandrel and the high-pressure rubber tube is linear, so that the high-pressure rubber tube moves along the same line with the drill pipe and the water braid, and the radial pulling of the rubber tube on the water braid is avoided.

[0012] Further, the water braid shell has a clamping plane on the outer circle, so that the water braid can be clamped by a tool such as a pipe wrench or a wrench.

[0013] Advantages of the present application:

[0014] The water braid described in the present application adopts a combined mode of deep groove ball bearings and thrust ball bearings, two deep groove ball bearings bear radial force, and play a supporting role on the mandrel, so as to ensure the flexible rotation of the mandrel during use of the water braid; and the thrust ball bearing bears bearing force, so as to ensure that the internal parts of the water braid do not produce axial displacement when the water braid bears high-pressure water.

[0015] The water braid gland described in the present application adopts two sealing grooves, and the water braid shell forms a closed space filled with lubricating oil under the combined sealing effect of the gland sealing groove and the high-pressure combined sealing on the left side of the mandrel, so as to play a lubricating and rust-proof role on the bearing parts in the water braid shell, and also to maintain a certain pressure in the water braid shell to prevent water leakage.

[0016] The high-pressure combined sealing on the left side of the water braid mandrel described in the present application uses an open installation mode, and is fixed by a compression wire. The open installation can ensure that the skeleton of the combined sealing is not damaged during installation to the greatest extent, and the compression wire is left-handed thread to prevent the water braid from being unclamped during rotation with the drill pipe.

[0017] The water braid structure described in the present application adopts a linear arrangement of the drill pipe, the water braid shell, the mandrel and the high-pressure rubber tube, so that the high-pressure rubber tube moves along the same line with the drill pipe and the water braid, and the radial pulling of the rubber tube on the water braid is avoided.

[0018] The water braid shell has a clamping plane on the outer circle, so that the water braid can be clamped by a tool such as a pipe wrench or a wrench. BRIEF DESCRIPTION OF DRAWINGS

[0019] Fig. 1 The present application is an external view;

[0020] Fig. 2 The present application is an internal structure schematic view;

[0021] Fig. 3 The present application is a gland first and second sealing groove and water braid shell orifice sealing chamfer surface schematic view;

[0022] Reference numerals: 1. Mandrel, 2. Gland, 3. Seal I, 4. Thrust ball bearing, 5. Transition pressure plate, 7. Pressure wire, 8. High-pressure combination seal, 9. Water braid housing, 10. Water braid housing water passage hole, 11. Mandrel water passage hole, 13. Gland first sealing groove, 14. Gland second sealing groove, 15. Sealing chamfer surface, 17. Shoulder, 18. Bearing plane, 19. Seal II, 20. Housing front end inner hole, 21. Threaded inner hole, 22. Rotary bearing I, 23. Rotary bearing II, 24. Bearing mounting hole, 25. Drill rod connection thread. Detailed Implementation

[0023] like Figs. 1 to 3 As shown, a pressure-balanced ultra-high pressure sealed water braid includes a water braid housing (9), a pressure wire (7), a mandrel (1), a transition pressure plate (5), and a pressure cap (2) that are concentrically connected from left to right. In this example, the right side of the mandrel is connected to the high-pressure hose using a quick-connect coupling commonly used in coal mines, and the left side is connected to the drill rod with a thread matching the tail of the drill rod. The water braid housing (9) and the pressure cap (2) can rotate synchronously under the drive of the drill rod, while the mandrel remains relatively stationary with the high-pressure hose.

[0024] The gland (2) is fixed to the water braid housing (9) by bolts. The gland (2) is provided with a first sealing groove (13) and a second sealing groove (14), on which seal I (3) and seal II (19) are respectively placed to seal the gap between the mandrel (1) and the gland (2) and the gap between the gland (2) and the orifice of the water braid housing (9). Under the combined action of the two seals at the gland (2) and the high-pressure combined seal (8) at the left end of the mandrel, the sealed space formed inside the water braid housing (9) is filled with lubricating oil, which can not only lubricate and prevent rust on the bearing components inside the water braid housing, but also maintain a certain pressure inside the water braid housing to prevent water leakage.

[0025] High pressure combined seal (8) is arranged between the mandrel (1) and the inner hole of the water braid shell (9), the pressing wire (7) is provided with external thread, the inner hole (21) of the water braid shell (9) is provided with internal thread, the high pressure combined seal is fixed in the water braid shell (9) through the pressing wire (7) thread, the shaft shoulder (7) of the mandrel (1) is provided with rotating bearing I (22) and rotating bearing II (23) on the left and right sides respectively, the inner rings of the two bearings are all supported on the two sides of the shaft shoulder, the outer ring of the rotating bearing I (22) on the left side is supported on the left side of the inner hole (24) of the water braid shell, the inner ring of the rotating bearing II (23) on the right side is supported on the small diameter side of the transition pressure plate (5), the large diameter side of the transition pressure plate (5) is supported on the tight side of the thrust ball bearing (4), the loose side of the thrust ball bearing (4) is in contact with the pressing cover fixed on the water braid shell, the mandrel water hole (11) is arranged in the mandrel (1), the water braid shell water hole (10) is arranged on the water braid shell (9), the mandrel water hole (11) and the water braid shell water hole (10) are communicated, and the outer circle of the water braid shell is milled with the holding plane (18) to facilitate the holding of the water braid dismounting tool.

[0026] When the application is implemented, the right side of the mandrel (1) is connected with the high pressure rubber pipe, the left side of the water braid shell (9) is connected with the drill rod, the mandrel (1) and the high pressure rubber pipe are stationary relative to the water braid shell (9), and the pressing cover (2) rotates with the drill rod together with the water braid shell (9). The two seals of the pressing cover (2) can make the external dust, water and other impurities enter the water braid shell (9), and can also prevent the lubricating oil in the water braid shell (9) from leaking to ensure the lubrication, rust prevention, pressure maintenance and leakage prevention of the inside of the water braid shell (9). The high pressure combined seal (8) can prevent high pressure water from leaking from the contact between the relatively rotating water braid shell (9) and the left side of the mandrel (1), and prevent the loss of high pressure water pressure. The high pressure water passes through the mandrel water hole (11), the water braid shell water hole (10) and the drill rod in turn from the high pressure rubber pipe to the deep part of the drill hole. When the water braid of the application is dismounted, the holding plane (18) of the outer circle of the water braid shell can be clamped by using a pipe wrench and other tools, which is convenient and fast. The application has the characteristics of convenient connection, good sealing performance, excellent rust prevention and wear resistance, long service life and the like.

Claims

1. A pressure self-balancing ultra-high pressure seal water braid, characterized by: Its water braid shell (9), pressure wire (7), mandrel (1), transition pressure disc (5), gland (2), rotary bearing I (22), rotary bearing II (23) and thrust ball bearing (4), above from left to right concentric connection; Water braid shell (9) left side has and drill pipe matching thread and drill pipe is connected, right side mandrel (1) and high pressure rubber tube is connected; The mandrel (1) passes through the pressure wire (7), the transition pressure disc (5), the gland (2) and goes into the water braid shell (9) inside, the mandrel (1) and the water braid shell (9) are relatively rotatablely connected;The gland (2) is connected with the water braid shell (9), the gland (2) is provided with first sealing groove (13) and second sealing groove (14), the right side orifice of the water braid shell (9) is provided with sealing chamfer surface (15) matched with the second sealing groove (14) of the gland (2), and sealing elements are arranged in the first sealing groove (13) and the second sealing groove (14). High pressure combined seal (8) is arranged between the inner hole (20) of the shell front end of the mandrel (1) and the water braid shell (9), the pressure wire (7) is provided with external thread, the threaded inner hole (21) of the water braid shell (9) is provided with internal thread, the high pressure combined seal (8) is fixed in the water braid shell (9) through the thread of the pressure wire (7), the shaft shoulder (17) of the mandrel (1) is provided with rotary bearing I (22) and rotary bearing II (23) on the left and right sides respectively, the inner rings of the two bearings are all supported on the two sides of the shaft shoulder (17), the outer ring of the rotary bearing I (22) is supported on the left side of the bearing mounting hole (24), the inner ring right side of the rotary bearing II (23) is supported on the small diameter side of the transition pressure disc (5), the large diameter side of the transition pressure disc (5) is supported on the tight side of the thrust ball bearing (4), and the loose side of the thrust ball bearing (4) is connected with the gland (2) fixed on the water braid shell (9), the mandrel (1) is provided with mandrel water hole (11), the water braid shell (9) is provided with water braid shell water hole (10), the mandrel water hole (11) and the water braid shell water hole (10) are communicated, and the outer circle of the water braid shell (9) is milled with a clamping plane (18) to facilitate the clamping of the water braid dismounting tool.

2. A pressure self-balancing ultra-high pressure seal water strand according to claim 1, characterized in that: The gland (2) is provided with first sealing groove (13) and second sealing groove (14), the right side orifice of the water braid shell (9) is provided with sealing chamfer surface (15) matched with the second sealing groove (14) of the gland (2), sealing element I (3) and sealing element II (19) are respectively arranged in the two sealing grooves, and the gaps between the mandrel (1) and the gland (2) and the gaps between the gland (2) and the water braid shell (9) are sealed.

3. A pressure self-balancing ultra-high pressure seal water strand according to claim 1, characterized in that: The high pressure combined seal (8) adopts "open type" installation mode, the pressure wire (7) is fixed in the threaded inner hole (21) of the water braid shell (9) through thread, which fixes the high pressure combined seal (8), and the pressure wire (7) and the internal thread of the threaded inner hole (21) are left-handed threads.

4. A pressure self-balancing ultra-high pressure seal water strand according to claim 1, characterized in that: Under the effect of high pressure combination seal (8) and seal I (3), seal II (19), a sealed space is formed inside the water braid shell (9), which is filled with lubricating oil, which will play the effect of hydraulic balance on both ends of the high pressure combination seal (8) and also has the effect of preventing high pressure water from penetrating, and also plays the role of lubricating the seal ring and the bearing.

5. A pressure self-balancing ultrahigh pressure seal water braid according to claim 1, wherein: The internal bearing arrangement adopts a combined form, wherein the rotary bearing I (22) and the rotary bearing II (23) used are deep groove ball bearings, the rotary bearing I (22) and the rotary bearing II (23) play a supporting role between the water braid shell (9) and the mandrel (1), bear radial load, and ensure axial concentricity, and the thrust ball bearing (4) bears the thrust of the high pressure water to the right side of the mandrel (1) between the transition pressure disc (5) and the pressure cover (2), bears axial load, and ensures smooth rotation of the mandrel (1).

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