Abrasive water jet tunneling machine remote phased active sand supply system

Abstract

The application relates to the technical field of heading machines, and provides a long-distance staged active sand supply system of an abrasive water jet heading machine, which comprises a rotation center, a pneumatic conveying device and an abrasive degassing device which are sequentially connected; a sand storage ring is formed between the stationary shell of the rotation center and the rotation core; a gas distribution bin, a second high-pressure gas pipeline and a second abrasive pipeline are arranged in the rotation core; the sand storage ring is connected to a sand box, and the abrasive in the sand box is conveyed to the sand storage ring through a pneumatic conveying mode; the sand storage ring is connected to the pneumatic conveying device through the second abrasive pipeline, the gas distribution bin is connected to the pneumatic conveying device through the second high-pressure gas pipeline, and after the gas enters the pneumatic conveying device, a gas pressure difference is formed, so that the abrasive enters the abrasive degassing device under the action of the gas pressure difference; the abrasive degassing device is connected to a water jet cutter sand mixing cavity, and the abrasive in the abrasive degassing device enters the water jet cutter sand mixing cavity under the action of the negative pressure generated by the water jet. The long-distance sand supply problem from the sand box on the trolley to the cutter head is solved.

Description

Technical Field

[0001] This invention relates to the field of tunneling machine technology, and in particular to a long-distance, phased active sand supply system for an abrasive waterjet tunneling machine. Background Technology

[0002] The statements in this section are merely background information related to the present invention and do not necessarily constitute prior art.

[0003] Tunnel boring machines (TBMs), as highly integrated construction equipment for urban underground tunnels, have advantages such as minimal environmental disturbance and high safety and reliability, and are widely used in the construction of urban underground space projects. However, with the deepening of their application, the safe and efficient passage of TBMs through reinforced concrete structures, extremely hard rock, and isolated boulders has become a current bottleneck problem.

[0004] High-pressure abrasive waterjet technology, due to its advantages of low energy consumption, high efficiency, and safety, has been applied in fields such as mineral resource extraction and machining. High-pressure waterjet pre-cuts in rock masses and reinforced concrete structures, reducing the strength of obstacles and significantly improving the cutting capabilities of mechanical equipment. Currently, significant breakthroughs have been achieved in both theory and technology for waterjet-equipped TBMs and shield tunneling machines for rock breaking and obstacle clearance.

[0005] However, tunneling machines equipped with water jets face challenges in multi-media rotary transmission, especially in the long-distance quantitative transmission of abrasive materials. This is mainly because the large structure of tunneling machines results in a long single-trip sand supply distance, leading to problems such as insufficient sand supply and difficulty in quantitative sand supply when the tunneling machine is equipped with an abrasive water jet system. This is also the key obstacle preventing abrasive water jet-assisted tunneling machines from being applied in engineering. Summary of the Invention

[0006] To address the shortcomings of existing technologies, this invention provides a long-distance, phased, active sand supply system for an abrasive waterjet tunneling machine. The first phase involves conveying sand from the sand box to the sand storage ring using pneumatic high-pressure methods. The second phase involves conveying sand from the sand storage ring to the abrasive deaeration device using a pneumatic conveying pump. The third phase involves the negative pressure generated by the high-pressure water jet drawing the abrasive from the abrasive deaeration device into the waterjet mixing chamber. This phased, active pneumatic sand supply system solves the problem of long-distance sand supply from the sand box on the trolley to the cutterhead.

[0007] To achieve the above objectives, the present invention adopts the following technical solution:

[0008] The first aspect of the present invention provides a long-distance, phased active sand supply system for an abrasive waterjet tunneling machine.

[0009] A long-distance, phased active sand supply system for an abrasive waterjet tunneling machine includes a rotating center, a pneumatic conveying device, and an abrasive degassing device connected in sequence; a sand storage ring is formed between the stationary shell of the rotating center and the following core of the rotating center; and an air distribution chamber, a second high-pressure air pipeline, and a second abrasive pipeline are provided inside the following core of the rotating center.

[0010] The sand storage ring is connected to the sand box, and the abrasive in the sand box is transported to the sand storage ring by pneumatic high pressure.

[0011] The sand storage ring is connected to the pneumatic conveying device through the second abrasive pipeline, and the gas distribution chamber is connected to the pneumatic conveying device through the second high-pressure gas pipeline. After the gas in the gas distribution chamber enters the pneumatic conveying device, a pressure difference is formed in the pneumatic conveying device, so that the abrasive entering the pneumatic conveying device enters the abrasive degassing device under the action of the pressure difference.

[0012] The abrasive degassing device is connected to the water jet mixing chamber via a hose, and the abrasive in the abrasive degassing device enters the water jet mixing chamber under the negative pressure generated by the water jet.

[0013] Furthermore, the rotary center is also equipped with a high-pressure water pipeline connected to the water jet nozzle on the cutter head.

[0014] Furthermore, the pneumatic conveying device is connected to a control valve, which adjusts the cross-sectional area of ​​the pipe to control the amount of abrasive and the flow rate. The control valve is used to adjust the abrasive flow rate in the abrasive channel.

[0015] Furthermore, the gas distribution chamber is connected to an air pump, and the air pressure and flow rate of the gas entering the gas distribution chamber can be adjusted by controlling the air pump.

[0016] Furthermore, the abrasive degassing device includes a bearing and an internal component disposed within the bearing. The outer ring of the bearing is fixed to the cutter head, and rollers are disposed between the outer ring of the bearing and the internal component.

[0017] Furthermore, the internal component is a hollow column with its interior hollowed out in a fan shape, and a sand inlet pipe is provided on the first end face of the internal component, and a sand outlet pipe is provided on the second end face of the internal component. The sand inlet pipe is connected to the pneumatic conveying device, and the sand outlet pipe is connected to the water jet sand mixing chamber.

[0018] Furthermore, the second end face of the internal component is provided with an exhaust hole, and the height of the exhaust hole is the same as that of the sand inlet pipe.

[0019] Furthermore, the sand storage ring is provided with an abrasive inlet, an exhaust outlet, and an anti-clogging sand discharge outlet;

[0020] The sand storage ring is connected to the sand box through the abrasive inlet, and the exhaust port and anti-clogging sand discharge port are located on the opposite side of the abrasive inlet.

[0021] Furthermore, the pneumatic conveying device has an axially extending abrasive channel with a variable diameter. The end of the abrasive channel with a larger opening is connected to the second abrasive pipeline, and the end of the abrasive channel with a smaller opening is connected to the abrasive degassing device.

[0022] A second aspect of the present invention provides a tunneling machine.

[0023] A tunneling machine employs the long-distance, phased active sand supply system for an abrasive waterjet tunneling machine as described in the first aspect.

[0024] Compared with the prior art, the beneficial effects of the present invention are:

[0025] 1. The present invention discloses a long-distance, phased active sand supply system for an abrasive waterjet tunneling machine. The first stage is to transport sand from the sand box to the sand storage ring using a pneumatic high-pressure method; the second stage is to transport sand from the sand storage ring to the abrasive deaeration device using a pneumatic conveying device; the third stage is to use the negative pressure generated by the high-pressure water jet to draw the abrasive in the abrasive deaeration device into the water jet mixing chamber. This system realizes phased active pneumatic sand supply and solves the problem of long-distance sand supply from the sand box on the trolley to the cutterhead.

[0026] 2. The abrasive waterjet tunneling machine remote-controlled phased active sand supply system of the present invention adopts a numerical control system to control the sand supply. The sand supply can be adjusted in two ways: first, by adjusting the air pump parameters through the numerical control system; second, by adjusting the state of the control valve behind the pneumatic conveying device through the numerical control system to adjust the sand supply flow rate. This achieves two-stage adjustment of the sand supply, thereby achieving precise control of the abrasive flow rate and ensuring continuous sand supply.

[0027] 3. The present invention provides a long-distance, phased active sand supply system for an abrasive waterjet tunneling machine, which proposes an abrasive degassing device to achieve gas-sand separation. Gas is discharged through the exhaust port, and abrasive is deposited at the bottom of the abrasive degassing device, which greatly reduces the gas content of the abrasive when it is output from the bottom, thereby reducing the disturbance of gas to the waterjet and increasing the effective target distance. Attached Figure Description

[0028] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments and descriptions of the invention are used to explain the invention and do not constitute an improper limitation of the invention.

[0029] Figure 1 This is a structural diagram of the long-distance, phased, active sand supply system according to Embodiment 1 of the present invention;

[0030] Figure 2This is a structural diagram of the rotation center in Embodiment 1 of the present invention;

[0031] Figure 3 This is a cross-sectional view of the rotation center in Embodiment 1 of the present invention;

[0032] Figure 4 This is a schematic diagram of the pneumatic conveying device according to Embodiment 1 of the present invention;

[0033] Figure 5 This is a structural diagram of the abrasive degassing device according to Embodiment 1 of the present invention;

[0034] Figure 6 This is a cross-sectional view of the abrasive degassing device of Embodiment 1 of the present invention;

[0035] Figure 7 This is a structural diagram of the internal components of Embodiment 1 of the present invention. Detailed Implementation

[0036] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0037] It should be noted that the following detailed descriptions are exemplary and intended to provide further illustration of the invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0038] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of exemplary embodiments according to the invention. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0039] In this invention, terms such as "upper," "lower," "left," "right," "front," "back," "vertical," "horizontal," "side," and "bottom" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. These terms are used only to facilitate the description of the structural relationships of the various components or elements of this invention and do not specifically refer to any component or element in this invention. They should not be construed as limiting the invention.

[0040] In this invention, terms such as "fixed connection," "connected," and "linked" should be interpreted broadly, indicating a fixed connection, an integral connection, or a detachable connection; a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can determine the specific meaning of these terms in this invention based on the specific circumstances, and they should not be construed as limitations on the invention.

[0041] Where there is no conflict, the embodiments and features in the embodiments of the present invention can be combined with each other.

[0042] Example 1

[0043] Embodiment 1 of the present invention provides a long-distance, phased active sand supply system for an abrasive waterjet tunneling machine.

[0044] This embodiment provides a long-distance, phased active sand supply system for abrasive waterjet tunneling machines, applicable to abrasive waterjet tunneling machines.

[0045] To address the issue of continuous sand supply over long distances, this embodiment provides a long-distance, phased, active sand supply system for an abrasive waterjet tunneling machine. The system employs a phased delivery design: the first phase involves transporting sand from the sand box to the sand storage ring using pneumatic high-pressure methods; the second phase involves transporting sand from the sand storage ring to the abrasive deaeration device using a pneumatic pumping device; and the third phase utilizes the negative pressure generated by the high-pressure water jet to draw the abrasive from the abrasive deaeration device into the water jet mixing chamber.

[0046] like Figure 1 As shown in the figure, this embodiment provides a long-distance, staged active sand supply system for an abrasive waterjet tunneling machine, comprising: a CNC system 1, an air pump 2, a sand box 3, a pneumatic conveying device 4, a control valve 5, a rotary center 6, and an abrasive degassing device (hereinafter referred to as degassing device or degassing mechanism) 7 installed on the cutterhead. The pneumatic conveying device 4 and the control valve 5 are sequentially installed on the output side of the rotary center 6.

[0047] like Figure 2 and Figure 3 As shown, the rotation center 6 is divided into a stationary outer shell 611 and a rotating core 612 (as shown in the figure). Figure 3 As shown, the obliquely marked outer shell is the stationary outer shell, and the unfilled internal part is the rotating core. The rotating core provides pipeline channels for various media (abrasive, gas, high-pressure water, foam, and oil, etc.) and rotates coaxially with the cutter head. The stationary outer shell connects to the input pipelines of each phase material; the rotating core contains the output pipelines of each phase material, and the output pipelines can maintain the same rotational speed as the cutter head. A sand storage ring 606 is located on the stationary outer shell adjacent to the rotating core, and a gas distribution chamber 607 is located inside the rotating core. The stationary outer shell and the rotating core are connected and rotated by bearings, with a sealing ring on the outside of the bearings. To prevent sand blockage inside the sand storage ring 606, a sand discharge port 603 is provided on its outside to drain sand. An exhaust port 604 is located next to the sand discharge port 603, which can balance the air pressure of the sand storage ring 606.

[0048] like Figure 2 and Figure 3 As shown, the diameter of the rotating core of the rotary center 6 is larger at one end near the cutter head than at the other end.

[0049] like Figure 2 and Figure 3 As shown, the stationary outer shell of the rotation center 6 includes a first sleeve and a second sleeve.

[0050] A high-pressure water pipeline 601 is installed on the central axis of the rotating core; the inlet of the high-pressure water pipeline 601 is connected to a high-pressure water rotary joint 9; and the outlet of the high-pressure water pipeline 601 is connected to a water jet nozzle.

[0051] The first sleeve is located on the side of the rotating core away from the cutter head. Several high-pressure air inlets are arranged on the surface of the first sleeve. The first end of the first high-pressure air pipeline 602 inside the rotating core is connected to the air pump 2 through a high-pressure air inlet. The first high-pressure air pipeline 602 inside the rotating core is arranged around the high-pressure water pipeline 601, and each high-pressure air inlet is connected to one first high-pressure air pipeline 602. The second end of the first high-pressure air pipeline 602 is connected to the air distribution chamber 607 inside the rotating core. A second high-pressure air pipeline 609 is provided inside the rotating core of the rotation center 6. One end of the second high-pressure air pipeline 609 is connected to the air distribution chamber 607, and the other end is connected to the pneumatic conveying device.

[0052] The surface of the first sleeve is also provided with several other medium inlets 610, such as foam and oil passages, which are connected to other medium pipelines opened inside the rotating core. These other medium pipelines are connected to the cutter head.

[0053] The second sleeve is fitted on the outside of the rotating core, forming a sand storage ring 606 between the sleeve and the rotating core. That is, the sand storage ring 606 adopts the sleeve form.

[0054] The outer surface of the second sleeve has an abrasive inlet (abrasive entrance) 605, an exhaust port 604, and an anti-clogging sand discharge port 603, all of which are connected to the sand storage ring 606. The abrasive inlet 605 is connected to the first abrasive pipeline, which in turn connects to the sand box 3. The exhaust port 604 is connected to the sand storage ring 606 and can balance the air pressure inside the sand storage ring 606. The exhaust port 604 and the anti-clogging sand discharge port 603 are located on the opposite side of the abrasive inlet 605, and during use, the abrasive inlet 605 is located at the top of the stationary outer shell (second sleeve) of the rotation center 6. A second abrasive pipeline (located on the side with the larger diameter) is installed inside the rotating core. The inlet of the second abrasive pipeline is connected to the sand storage ring 606. The second abrasive pipeline 608 is located outside the high-pressure water pipeline and the first high-pressure air pipeline 602, and the outlet of the second abrasive pipeline is connected to the pneumatic conveying device.

[0055] The abrasive storage ring 606, located at the rotary center 6, temporarily stores the abrasive input from the external abrasive path. After the abrasive path is introduced into the storage ring 606, the abrasive deposits inside. Excess gas is discharged through the exhaust port 604, which is lined with a one-way gas-guiding membrane. A rubber hose is connected to the outlet of the storage ring 606, forming the second abrasive pipeline. This rubber hose connects to the pneumatic conveying device 4, which can also be flexibly connected to the abrasive degassing device on the cutter head using a rubber hose.

[0056] When the sand has accumulated beyond all the sand outlets, the pneumatic conveying device 4 can be activated to begin the second stage of abrasive conveying.

[0057] like Figure 4 As shown, the pneumatic conveying device 4 has an internal diameter variable and connects to both a second high-pressure air pipeline and a second abrasive pipeline. The pneumatic conveying device 4 has an axially extending abrasive channel 402 with a variable diameter (the abrasive direction is from the larger opening to the smaller opening; the larger opening end of the abrasive channel 402 connects to the second abrasive pipeline, and the smaller opening end connects to the sand inlet pipe 704 via a third abrasive pipeline 8). The pneumatic conveying device 4 also has an inlet 401 on the side connected to the second abrasive pipeline. The inlet 401 is connected to the abrasive channel 402 via a control valve and is also connected to the second high-pressure air pipeline. When high-pressure gas (gas in the exhaust port) is introduced, due to the special internal structure, a low-pressure zone (at the smaller opening) and a high-pressure zone (at the larger opening) are formed inside the pneumatic conveying device 4. The abrasive flows from the high-pressure zone to the low-pressure zone, thus conveying the abrasive towards the cutter head. The pneumatic conveying device 4 is connected to a control valve to regulate the abrasive flow rate.

[0058] The CNC system 1 can control the air pump 2, adjusting the air pressure and flow rate; it can also adjust the control valve connected to the pneumatic conveying device 4. The regulation of these two parts can achieve precise control of the abrasive flow rate, thereby ensuring the stability of sand transportation and realizing quantitative sand supply.

[0059] like Figure 5 and Figure 6 As shown, the abrasive degassing device 7 includes a bearing and an internal component 706 disposed within the bearing. The bearing consists of an outer ring and rollers 705 arranged sequentially from the outside in. Several rollers 705 are disposed between the internal component 706 and the outer ring, and the outer ring is fixed to the cutter head. Figure 7 As shown, the internal component 706 is a hollow column with its interior hollowed out in a fan shape. A sand inlet pipe 704 is provided on the first end face of the internal component 706, and a sand outlet pipe 701 is provided on the second end face. Several vent holes 702 are also provided on the second end face of the internal component 706. The sand outlet pipe 701 is located at the apex of the fan-shaped hollow area of ​​the internal component 706, and the sand inlet pipe 704 is located at the center of the arc edge of the fan-shaped hollow area of ​​the internal component 706. The vent holes 702 and the sand inlet pipe 704 are at the same height.

[0060] Among them, a one-way gas guiding membrane 703 is provided on the second end face of the internal component 706 at the exhaust hole 702 to prevent external gas from entering due to pressure difference.

[0061] The internal components can rotate relative to the cutter head, ensuring that the abrasive is deposited in the lower part. The internal components 706 rotate detached from the cutter head. When the cutter head rotates, the internal components 706 always keep the sand outlet pipe 701 in the lower part. The fan-shaped hollowing of the internal components 706 is to increase the mass of the lower part, so that the internal part of the abrasive degassing device can better detach from the outer ring and keep the sand outlet pipe 701 in the lower part.

[0062] The cutter head is equipped with a water jet nozzle, which is connected to the outlet of the high-pressure water pipeline 601. The water jet mixing chamber is connected to the sand outlet pipe 701 of the abrasive degassing device through the abrasive transport hose. The sand inlet pipe 704 of the abrasive degassing device is connected to the abrasive channel 402.

[0063] The abrasive degassing device adopts the same form as the bearing. The internal component 706 can rotate relative to the cutter head, ensuring that the abrasive is always deposited at the bottom. A sand outlet pipe 701 is installed at the bottom, connected to the abrasive transport hose to ensure smooth abrasive passage. An exhaust port 702 is opened at the top of the abrasive degassing device to allow gas to escape from above. A one-way gas-guiding film is attached to the inner side of the exhaust port 702. Since the sand outlet pipe 701 is connected to the water jet mixing chamber through the abrasive transport hose, a negative pressure is created when the water jet is ejected at high speed. This negative pressure forces the abrasive through the abrasive transport hose and into the water jet at the nozzle.

[0064] This embodiment provides a long-distance, staged active sand supply system for an abrasive waterjet tunneling machine. The first stage involves conveying sand from the sand box to the sand storage ring using pneumatic high-pressure pumping. The second stage involves conveying sand from the sand storage ring to the abrasive deaeration device using a pneumatic pumping device. In the third stage, the negative pressure generated by the high-pressure water jet draws the abrasive from the abrasive deaeration device into the water jet mixing chamber. A sand quantity control valve is designed at the abrasive outlet of the abrasive deaeration device. This system achieves staged active pneumatic sand supply, solving the problem of long-distance sand supply from the sand box on the trolley to the cutterhead.

[0065] This embodiment provides a long-distance, phased active sand supply system for an abrasive waterjet tunneling machine. It adopts a numerical control system to control the sand supply amount. The sand supply amount can be adjusted in two ways. First, the parameters of the air pump 2 are adjusted by the numerical control system. Second, the sand supply flow rate is adjusted by adjusting the state of the control valve behind the pneumatic conveying device. This achieves two-stage adjustment of the sand supply amount, so as to accurately control the abrasive flow rate and ensure the continuity of sand supply.

[0066] This embodiment provides a long-distance, phased active sand supply system for an abrasive waterjet tunneling machine. It proposes an abrasive degassing device to achieve gas-sand separation. Gas is discharged through the exhaust port, and abrasive is deposited at the bottom of the abrasive degassing device, which greatly reduces the gas content of the abrasive when it is output from the bottom. This reduces the disturbance of gas to the waterjet and increases the effective target distance.

[0067] Example 2

[0068] Embodiment 2 of the present invention provides a tunneling machine.

[0069] This embodiment provides a tunneling machine that employs a long-distance, phased active sand supply system for an abrasive waterjet tunneling machine as described in Embodiment 1.

[0070] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A long-distance, staged active sand supply system for an abrasive waterjet tunneling machine, characterized in that: It includes a rotary center, a pneumatic conveying device, and an abrasive degassing device connected in sequence; a sand storage ring is formed between the stationary shell of the rotary center and the rotating core; and an air distribution chamber, a second high-pressure air pipeline, and a second abrasive pipeline are provided inside the rotating core of the rotary center. The sand storage ring is connected to the sand box, and the abrasive in the sand box is transported to the sand storage ring by pneumatic high pressure. The sand storage ring is connected to the pneumatic conveying device through the second abrasive pipeline, and the gas distribution chamber is connected to the pneumatic conveying device through the second high-pressure gas pipeline. After the gas in the gas distribution chamber enters the pneumatic conveying device, a pressure difference is formed in the pneumatic conveying device, so that the abrasive entering the pneumatic conveying device enters the abrasive degassing device under the action of the pressure difference. The abrasive degassing device is connected to the water jet mixing chamber, and the abrasive in the abrasive degassing device enters the water jet mixing chamber under the negative pressure generated by the water jet. The abrasive degassing device includes a bearing and an internal component disposed within the bearing. The outer ring of the bearing is fixed to the cutter head, and rollers are disposed between the outer ring of the bearing and the internal component. The internal component is a hollow column with the interior hollowed out in a fan shape. The first end face of the internal component is provided with a sand inlet pipe, and the second end face of the internal component is provided with a sand outlet pipe. The sand inlet pipe is connected to the pneumatic conveying device, and the sand outlet pipe is connected to the water jet sand mixing chamber. The second end face of the internal component is provided with an exhaust hole, and the height of the exhaust hole is the same as that of the sand inlet pipe; The pneumatic conveying device has an axially extending abrasive channel with varying diameter. The end of the abrasive channel with a larger opening is connected to the second abrasive pipeline, and the end of the abrasive channel with a smaller opening is connected to the abrasive degassing device.

2. The long-distance, staged active sand supply system for an abrasive waterjet tunneling machine as described in claim 1, characterized in that: The rotary center is also equipped with a high-pressure water pipeline connected to the water jet nozzle on the cutter head.

3. The long-distance, staged active sand supply system for an abrasive waterjet tunneling machine as described in claim 1, characterized in that: The pneumatic conveying device is connected to a control valve, which is used to adjust the abrasive flow rate in the abrasive channel.

4. The long-distance, staged active sand supply system for an abrasive waterjet tunneling machine as described in claim 1, characterized in that: The gas distribution chamber is connected to an air pump, and the air pressure and flow rate of the gas entering the gas distribution chamber can be adjusted by controlling the air pump.

5. The long-distance, staged active sand supply system for an abrasive waterjet tunneling machine as described in claim 1, characterized in that: The sand storage ring is equipped with an abrasive inlet, an exhaust outlet, and an anti-clogging sand discharge outlet. The sand storage ring is connected to the sand box through the abrasive inlet, and the exhaust port and anti-clogging sand discharge port are located on the opposite side of the abrasive inlet.

6. A tunneling machine, characterized in that: The abrasive waterjet tunneling machine adopts a long-distance, staged active sand supply system as described in any one of claims 1-5.

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