Hydraulic system and shield tunneling machine

Abstract

The hydraulic system comprises a propulsion oil cylinder, a two-way cartridge valve, a pressure reducing valve and a second one-way valve. The two-way cartridge valve has a first interface, a second interface and a control cavity. The first interface is connected with a control valve group. The second interface is connected with a first oil source and communicates with a rodless cavity of the propulsion oil cylinder. The control cavity communicates with the second interface through a control oil path. The pressure of the first oil source is configured to be greater than the pressure of a second oil source connected with the control valve group. The inlet of the pressure reducing valve communicates with the control cavity. The outlet of the pressure reducing valve communicates with the first interface through a first one-way valve. The second one-way valve is arranged between the first oil source and the second interface and allows oil to flow from the first oil source to the second interface. When the hydraulic system is powered off, the control valve group is closed to maintain pressure, and the control cavity and the second interface are pressure balanced, so that the two-way cartridge valve is in a closed state, the first interface and the second interface are cut off, and the pressure of the rodless cavity of the propulsion oil cylinder is maintained by the second one-way valve and the two-way cartridge valve.

Description

Technical Field

[0001] This disclosure relates to the field of hydraulic transmission control technology, and more specifically, to a hydraulic system and a tunnel boring machine. Background Technology

[0002] During tunnel construction, due to complex and variable geological conditions, even when the propulsion system operates under normal pressure, shield tunneling machines may experience jamming due to load resistance exceeding the upper limit. The conventional approach is to increase the pressure of the propulsion hydraulic system or add an auxiliary high-pressure escape system. Currently, there are relatively few types of ultra-high-pressure hydraulic components, and their cost is high. Furthermore, ultra-high-pressure escape is a short-term, high-load condition; upgrading the entire propulsion system to an ultra-high-pressure design would result in extremely poor system economy. Therefore, existing shield tunneling machine ultra-high-pressure escape systems typically employ a localized ultra-high-pressure approach, balancing localized ultra-high-pressure efficiency with overall economic efficiency.

[0003] Current ultra-high pressure escape systems for tunnel boring machines (TBMs) typically use manual ball valves to switch and isolate the ultra-high pressure escape oil source from the propulsion cylinders from the normal mode oil source. Specifically, two ultra-high pressure ball valves are installed in parallel in the rodless chamber of the propulsion cylinder: one controls the oil supply for ultra-high pressure escape, and the other controls the oil supply for the normal propulsion system. When ultra-high pressure escape is needed, the normal oil supply ball valve is closed, and the ultra-high pressure oil supply ball valve is opened. When ultra-high pressure escape is not needed, the normal oil supply ball valve is opened, and the ultra-high pressure oil supply ball valve is closed. While this method balances economy and performance to some extent, it requires switching the ball valves of all cylinders in the propulsion system individually, which is overly cumbersome and carries the risk of misoperation. Summary of the Invention

[0004] In view of this, the present disclosure provides a hydraulic system and a tunnel boring machine to overcome some of the technical problems of the aforementioned related technologies.

[0005] One aspect of this disclosure provides a hydraulic system including a propulsion cylinder, a two-way cartridge valve, a pressure reducing valve, and a second check valve. The two-way cartridge valve has a first port, a second port, and a control chamber. The first port is connected to a control valve assembly, the second port is connected to a first oil source and communicates with the rodless chamber of the propulsion cylinder, and the control chamber is connected to the second port via a control oil circuit. The pressure of the first oil source is configured to be greater than the pressure of the second oil source connected to the control valve assembly. The inlet of the pressure reducing valve communicates with the control chamber, and the outlet of the pressure reducing valve communicates with the first port via a first check valve. The second check valve is located between the first oil source and the second port and allows oil to flow from the first oil source to the second port. When the hydraulic system is de-energized, the control valve assembly closes to maintain pressure, and the pressures of the control chamber and the second port are balanced, causing the two-way cartridge valve to be in a closed state, cutting off the first and second ports. The pressure in the rodless chamber of the propulsion cylinder is maintained jointly by the second check valve and the two-way cartridge valve.

[0006] According to embodiments of this disclosure, the pressure-bearing area of ​​the valve core control chamber end of the two-way cartridge valve is configured to be greater than the pressure-bearing area of ​​the second interface end; and the sum of the pressure-bearing area of ​​the first interface end and the pressure-bearing area of ​​the second interface end of the two-way cartridge valve is equal to the pressure-bearing area of ​​the valve core control chamber end.

[0007] According to embodiments of this disclosure, the ratio of the pressure-bearing area of ​​the valve core control chamber end to the pressure-bearing area of ​​the second interface end is 3:1; and / or, the ratio of the pressure-bearing area of ​​the first interface end to the pressure-bearing area of ​​the second interface end is 2:1.

[0008] According to embodiments of this disclosure, the set opening pressure threshold of the pressure reducing valve is configured to be less than the first pressure of the first oil source, less than the second pressure of the second oil source, and less than the rated pressure of the control valve assembly.

[0009] According to embodiments of this disclosure, the first pressure is configured to be greater than or equal to 420 bar; and / or, the second pressure is configured to be less than or equal to 350 bar.

[0010] According to embodiments of this disclosure, the hydraulic system has an escape mode, a thrust extension mode, and a thrust retraction mode. In the escape mode, a first oil source is configured to supply oil to a second port, the pressure in the control chamber is equal to that in the second port, and a two-way cartridge valve cuts off the first port from the second port through the pressure-bearing area difference of the valve core. In the thrust extension mode, a control valve assembly is configured to supply oil to the first port, the pressure in the control chamber is released through a pressure reducing valve and a first check valve, and a two-way cartridge valve connects the first port to the second port so that the oil from the second oil source enters the rodless chamber of the thrust cylinder. In the thrust retraction mode, the control valve assembly connects the first port to return oil, the pressure in the control chamber is released through a pressure reducing valve and a first check valve, and a two-way cartridge valve connects the second port to the first port.

[0011] According to embodiments of this disclosure, a two-way cartridge valve, a pressure reducing valve, a first check valve, and a second check valve are all mounted on the same valve block; the valve block has: a first oil passage connecting a first interface to a control valve group; a second oil passage connecting a second interface to a first oil source; a control oil passage connecting a control chamber to a second interface; a pressure reducing valve and a first check valve connected in series between the control oil passage and the first oil passage; and a second check valve disposed in the second oil passage.

[0012] According to an embodiment of this disclosure, the hydraulic system further includes a first damping orifice, one end of which is connected to a second interface and the other end of which is connected to a control chamber, and is configured to form a pressure difference between the second interface and the control chamber when oil returns to the control chamber.

[0013] According to embodiments of this disclosure, the hydraulic system further includes a second damping orifice, an oil passage connected in series between the control chamber and the second interface, configured to reduce vibration during the opening and closing of the insert of the two-way cartridge valve.

[0014] According to embodiments of this disclosure, a tunnel boring machine (TBM) is provided, including a shield body and a hydraulic system as described in any of the above embodiments. The propulsion cylinder of the hydraulic system is disposed on the shield body, and the piston rod of the propulsion cylinder is configured to drive the shield body forward or to escape obstacles. The control valve group of the hydraulic system is disposed in the control system of the shield body and is configured to control the extension and retraction of the propulsion cylinder in propulsion mode. A first oil source of the hydraulic system is configured to provide the propulsion cylinder with a pressure higher than that of a second oil source in escape mode.

[0015] According to the hydraulic system and tunnel boring machine (TBM) provided in this disclosure, the TBM achieves switching between an escape mode and a normal propulsion mode by integrating the aforementioned hydraulic system. During normal propulsion, the control valve group controls the propulsion cylinder to drive the shield body at conventional pressure. When escape is required, the first oil source provides ultra-high pressure hydraulic fluid, and the two-way cartridge valve automatically closes and isolates the high-pressure oil circuit according to the pressure status. The ultra-high pressure hydraulic fluid enters the rodless chamber of the propulsion cylinder through the second check valve, providing escape thrust. In the event of a power outage, the hydraulic system can also passively maintain pressure in the rodless chamber to prevent the shield body from sliding backward. Attached Figure Description

[0016] The above and other objects, features, and advantages of this disclosure will become clearer from the following description of embodiments of the present disclosure with reference to the accompanying drawings, in which:

[0017] Figure 1 A schematic diagram of a hydraulic system provided for an illustrative embodiment of this disclosure.

[0018] Figure label:

[0019] 1. Propulsion cylinder; 11. Rodless chamber; 12. Rod chamber;

[0020] 2. Two-way cartridge valve;

[0021] 3. Second damping orifice;

[0022] 4. First damping orifice;

[0023] 5. Second check valve;

[0024] 6. Primary oil source;

[0025] 7. Pressure reducing valve;

[0026] 8. First check valve;

[0027] 9. Control valve assembly;

[0028] 10. Control cavity;

[0029] A. First interface;

[0030] B. Second interface;

[0031] 100. First oil passage;

[0032] 200. Second oil passage;

[0033] 300. Control the oil passage. Detailed Implementation

[0034] The embodiments of the present disclosure will now be described with reference to the accompanying drawings. However, it should be understood that these descriptions are exemplary only and are not intended to limit the scope of the disclosure. In the following detailed description, numerous specific details are set forth to provide a thorough understanding of the embodiments of the present disclosure for ease of explanation. However, it will be apparent that one or more embodiments may be practiced without these specific details. Furthermore, descriptions of well-known structures and techniques are omitted in the following description to avoid unnecessarily obscuring the concepts of the present disclosure.

[0035] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit this disclosure. The terms “comprising,” “including,” etc., as used herein indicate the presence of the stated features, steps, operations, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, or components.

[0036] All terms used herein (including technical and scientific terms) have the meanings commonly understood by those skilled in the art, unless otherwise defined. It should be noted that the terms used herein are to be interpreted in a manner consistent with the context of this specification, and not in an idealized or overly rigid way.

[0037] When using expressions such as "at least one of A, B and C", they should generally be interpreted in accordance with the meaning that is commonly understood by those skilled in the art (e.g., "a system having at least one of A, B and C" should include, but is not limited to, a system having A alone, a system having B alone, a system having C alone, a system having A and B, a system having A and C, a system having B and C, and / or a system having A, B and C, etc.).

[0038] Figure 1 A schematic diagram of a hydraulic system provided for an illustrative embodiment of this disclosure.

[0039] This disclosure provides a hydraulic system, with reference to Figure 1As shown, the system includes a propulsion cylinder 1, a two-way cartridge valve 2, a pressure reducing valve 7, and a second check valve 5. The two-way cartridge valve 2 has a first port A, a second port B, and a control chamber 10. The first port A is connected to a control valve assembly 9, and the second port B is connected to a first oil source 6 and communicates with the rodless chamber 11 of the propulsion cylinder 1. The control chamber 10 is connected to the second port B through a control oil circuit. The pressure of the first oil source 6 is configured to be greater than the pressure of the second oil source connected to the control valve assembly 9. The inlet of the pressure reducing valve 7 is connected to the control chamber 10, and the outlet of the pressure reducing valve 7 is connected to the first port A via a first check valve 8. The second check valve 5 is located between the first oil source 6 and the second port B and allows oil to flow from the first oil source 6 to the second port B. When the hydraulic system is de-energized, the control valve assembly 9 closes to maintain pressure, and the pressures of the control chamber 10 and the second port B are balanced, causing the two-way cartridge valve 2 to be in a closed state, cutting off the connection between the first port A and the second port B. The pressure in the rodless chamber 11 of the propulsion cylinder 1 is maintained by the second check valve 5 and the two-way cartridge valve 2.

[0040] In some illustrative embodiments, reference is made to Figure 1 As shown, the propulsion cylinder 1, as the actuator of this hydraulic system, is used to convert the pressure energy of the hydraulic fluid into mechanical energy to drive the shield of the tunnel boring machine forward. The propulsion cylinder 1 includes a rodless chamber 11 and a rod chamber 12. The rodless chamber 11 is directly connected to the second port B of the two-way cartridge valve 2, and is used to receive hydraulic fluid from the first oil source 6 or the second oil source connected to the control valve group 9 to push the piston rod out. The number of propulsion cylinders 1 can be selected according to the actual configuration of the tunnel boring machine propulsion system. One control valve group 9 can control one or more propulsion cylinders 1.

[0041] The two-way cartridge valve 2 is a component in this hydraulic system that enables oil circuit switching and pressure isolation. It has a first interface A, a second interface B, and a control chamber 10. The first interface A is connected to the control valve assembly 9 via an oil circuit. The second interface B is connected to the first oil source 6 via a second check valve 5, and also directly connected to the rodless chamber 11 of the propulsion cylinder 1. The control chamber 10 is connected to the second interface B via a control oil circuit. Regarding pressure configuration, the pressure of the first oil source 6 is configured to be greater than the pressure of the second oil source connected to the control valve assembly 9. Typically, the first oil source 6 is an ultra-high pressure oil source, usually a hydraulic booster assembly or an ultra-high pressure hydraulic pump assembly, used for ultra-high pressure escape conditions when the tunnel boring machine (TBM) is stuck; the second oil source is a conventional pressure oil source used for normal TBM tunneling conditions.

[0042] The inlet of the pressure reducing valve 7 is connected to the control chamber 10 of the two-way cartridge valve 2, and its outlet is connected to the first port A of the two-way cartridge valve 2 via the first check valve 8. Through this connection method, the pressure reducing valve 7 can control the pressure transmission path between the control chamber 10 and the first port A.

[0043] The second check valve 5 is located between the first oil source 6 and the second port B of the two-way cartridge valve 2. Its installation direction allows oil to flow only from the first oil source 6 to the second port B, while the reverse direction is blocked. The oil output from the first oil source 6 enters the second port B of the two-way cartridge valve 2 through the second check valve 5, and then enters the rodless chamber 11 of the propulsion cylinder 1, pushing the cylinder to extend.

[0044] In the above embodiment, the control chamber 10 of the two-way cartridge valve 2 is directly connected to its second port B, and a controllable pressure relief oil circuit is formed between the control chamber 10 and the first port A using a pressure reducing valve 7 and a first check valve 8. During the escape operation, the pressure reducing valve 7 is closed to cut off the oil circuit; during normal propulsion, the pressure reducing valve 7 is opened to open the oil circuit. A second check valve 5 is positioned between the first oil source 6 and the second port B. When the first oil source 6 is activated, ultra-high pressure oil enters the second port B through the second check valve 5 and connects to the rodless chamber 11 of the propulsion cylinder 1, directly driving the propulsion cylinder 1 to extend and provide ultra-high pressure escape thrust. At this time, because the pressure reducing valve 7 is closed, the oil circuit between the control chamber 10 and the first port A is not connected, and the pressure in the control chamber 10 remains equal to that in the second port B, ensuring that the two-way cartridge valve 2 is reliably closed.

[0045] When the hydraulic system experiences a sudden power outage, the control valve assembly 9 closes to maintain pressure. Simultaneously, the control chamber 10 of the two-way cartridge valve 2, due to its direct connection with the second interface B, achieves pressure balance, causing the two-way cartridge valve 2 to automatically close, cutting off the only return path of the rodless chamber 11 of the propulsion cylinder 1 via the first interface A. At the same time, the reverse shut-off function of the second check valve 5 prevents the oil in the rodless chamber 11 from flowing back to the first oil source 6. Together, these two mechanisms seal the pressure in the rodless chamber 11 between the propulsion cylinder 1 and the control valve assembly 9, achieving passive pressure maintenance during power outages.

[0046] In the above embodiment, when the hydraulic system is powered off, the control valve group 9 closes to maintain pressure, keeping the first port A in a closed state. Simultaneously, since the control chamber of the two-way cartridge valve 2 is directly connected to the second port B via the control oil circuit, the pressure in the control chamber 10 and the second port B is balanced. This pressure balance keeps the two-way cartridge valve 2 in the closed position, thereby cutting off the oil circuit between the first port A and the second port B. At this time, the oil in the rodless chamber 11 of the propulsion cylinder 1 cannot be released to the first port A side through the two-way cartridge valve 2, nor can it flow in the reverse direction to the first oil source 6 via the second check valve 5. Therefore, the pressure in the rodless chamber 11 of the propulsion cylinder 1 is maintained jointly by the second check valve 5 and the two-way cartridge valve 2, achieving passive pressure maintenance under power failure conditions. This resists external water and soil pressure, prevents the propulsion cylinder 1 from unexpectedly retracting, and improves the safety and reliability of the hydraulic system under extreme power failure conditions.

[0047] According to embodiments of this disclosure, the pressure-bearing area of ​​the valve core control chamber 10 end of the two-way cartridge valve 2 is configured to be greater than the pressure-bearing area of ​​the second interface B end; and the sum of the pressure-bearing area of ​​the first interface A end and the pressure-bearing area of ​​the second interface B end of the two-way cartridge valve 2 is equal to the pressure-bearing area of ​​the valve core control chamber 10 end. Specifically, at least one of the following ratios is satisfied: the ratio of the pressure-bearing area of ​​the valve core control chamber 10 end to the pressure-bearing area of ​​the second interface B end is 3:1; the ratio of the pressure-bearing area of ​​the first interface A end to the pressure-bearing area of ​​the second interface B end is 2:1.

[0048] In some illustrative embodiments, when the first oil source 6 supplies oil, the pressure of the second port B of the two-way cartridge valve 2 is equal to that of the control chamber 10. Since the pressure-bearing area at the end of the valve core control chamber 10 is greater than the pressure-bearing area at the end of the second port B, the downward closing force of the valve core control chamber 10 is greater than the upward opening force of the second port B, and the valve core is reliably closed.

[0049] When the control valve group 9 supplies oil to the first port A, the pressure in the control chamber 10 is released by the pressure reducing valve 7, the pressure in the control chamber 10 decreases, the downward closing force decreases, the valve core opens smoothly, and the oil is allowed to flow from the first port A to the second port B and enter the rodless chamber 11 of the propulsion cylinder 1.

[0050] When the hydraulic system is de-energized, the pressure in control chamber 10 and the second port B is balanced. Since the pressure-bearing area at the end of control chamber 10 is greater than that at the end of the second port B, the two-way cartridge valve 2 automatically remains closed and works in conjunction with the second check valve 5 to seal the pressure in the rodless chamber 11, achieving passive pressure maintenance. Furthermore, because the sum of the pressure-bearing areas at the first port A and the second port B equals the pressure-bearing area at the end of control chamber 10, the force on the valve core under various operating conditions satisfies the predictability of mechanical equilibrium, ensuring the smoothness and reliability of the opening and closing actions.

[0051] According to embodiments of this disclosure, the set opening pressure threshold of the pressure reducing valve 7 is configured to be less than the first pressure of the first oil source 6, and less than the second pressure of the second oil source and the rated pressure of the control valve assembly 9. Specifically, the first pressure is configured to be greater than or equal to 420 bar; and / or, the second pressure is configured to be less than or equal to 350 bar.

[0052] In some illustrative embodiments, the pressure reducing valve 7 is used to control the switching of the two-way cartridge valve. When the first oil source 6 supplies oil to increase the pressure of the second port B and the control chamber 10, the pressure on the first port A side has reached or exceeded the set threshold of the pressure reducing valve 7. The pressure reducing valve 7 remains closed, preventing the pressure in the control chamber 10 from being released, thereby ensuring that the two-way cartridge valve 2 is reliably closed.

[0053] When the control valve group 9 supplies or returns oil to the first port A, causing the pressure at the first port A to be lower than the set threshold of the pressure reducing valve 7, the pressure reducing valve 7 automatically opens, allowing the pressure in the control chamber 10 to be released, and the two-way cartridge valve 2 opens smoothly, restoring normal oil circuit conduction.

[0054] In some illustrative embodiments, the pressure reducing valve 7 can be replaced by a solenoid ball valve. The inlet of the solenoid ball valve is connected to the control chamber 10 of the two-way cartridge valve 2, and the outlet is connected to the first port A via the first check valve 8. The on / off state of the solenoid ball valve is controlled electrically. When the two-way cartridge valve 2 needs to be closed, the solenoid ball valve is controlled to close its valve port, preventing the pressure in the control chamber 10 from being released to the first port A, and the two-way cartridge valve 2 remains closed. When the two-way cartridge valve 2 needs to be opened, the solenoid ball valve is controlled to open its valve port, and the pressure oil in the control chamber 10 is released to the first port A via the solenoid ball valve and the first check valve 8, thus opening the two-way cartridge valve 2.

[0055] In some illustrative embodiments, the pressure reducing valve 7 can also be replaced by a hydraulically controlled check valve. The flow direction of the hydraulically controlled check valve is opposite to that of the first check valve 8; that is, the inlet of the hydraulically controlled check valve is connected to the first port A, and the outlet is connected to the control chamber 10. The control port of the hydraulically controlled check valve is taken from the rod chamber 12 of the propulsion cylinder 1. When the hydraulic rod of the propulsion cylinder 1 retracts, the return oil pressure in the rod chamber 12 increases, causing the hydraulically controlled check valve to open in the reverse direction, allowing the pressure oil in the control chamber 10 to be released to the first port A through the hydraulically controlled check valve, and the two-way cartridge valve 2 opens. When the hydraulic rod of the propulsion cylinder 1 extends or is stationary, the pressure in the rod chamber 12 is low, the hydraulically controlled check valve closes, preventing the pressure oil in the first port A from entering the control chamber 10, and at the same time, the pressure in the control chamber 10 cannot be released, so the two-way cartridge valve 2 remains closed.

[0056] According to embodiments of this disclosure, the hydraulic system has an escape mode, a thrust extension mode, and a thrust retraction mode. In the escape mode, the first oil source 6 is configured to supply oil to the second port B, the pressure in the control chamber 10 is equal to that in the second port B, and the two-way cartridge valve 2 cuts off the first port A from the second port B through the pressure-bearing area difference of the valve core. In the thrust extension mode, the control valve assembly 9 is configured to supply oil to the first port A, the pressure in the control chamber 10 is released through the pressure reducing valve 7 and the first check valve 8, and the two-way cartridge valve 2 connects the first port A and the second port B, so that the oil from the second oil source enters the rodless chamber 11 of the thrust cylinder 1. In the thrust retraction mode, the control valve assembly 9 connects the first port A to the return oil, the pressure in the control chamber 10 is released through the pressure reducing valve 7 and the first check valve 8, and the two-way cartridge valve 2 connects the second port B to the first port A.

[0057] In some illustrative embodiments, when the hydraulic system is in the escape mode, the first oil source 6 supplies oil to the second port B. Since the pressure in the control chamber 10 and the second port B are equal, and the pressure-bearing area of ​​the valve core control chamber 10 of the two-way cartridge valve 2 is greater than that of the second port B, the valve core cuts off the connection between the first port A and the second port B under the action of the pressure-bearing area difference. At this time, the oil enters the rodless chamber 11 of the propulsion cylinder 1 through the second check valve 5 and the second port B, driving the propulsion cylinder 1 to extend and provide escape thrust.

[0058] When the hydraulic system is in the thrust extension mode, the control valve group 9 supplies conventional pressure oil to the first port A. Since the set opening pressure threshold of the pressure reducing valve 7 is less than the pressure of the second oil source, and the pressure of the first port A is lower than this threshold, the pressure reducing valve 7 automatically opens. The pressure in the control chamber 10 is released to the first port A through the pressure reducing valve 7 and the first check valve 8, resulting in a decrease in the pressure in the control chamber 10. The valve core of the two-way cartridge valve 2 is subjected to an upward opening force, connecting the first port A and the second port B, allowing the oil from the second oil source to smoothly enter the rodless chamber 11 of the thrust cylinder 1, pushing the thrust cylinder 1 to extend smoothly.

[0059] When the hydraulic system is in the propulsion / retraction mode, the control valve assembly 9 connects the first port A to return oil. The pressure at the first port A rapidly drops to near zero, below the set opening pressure threshold of the pressure reducing valve 7. The pressure reducing valve 7 automatically opens, and the pressure in the control chamber 10 is released to the first port A through the pressure reducing valve 7 and the first check valve 8, thus reducing the pressure in the control chamber 10. Under the pressure of the second port B, the valve core of the two-way cartridge valve 2 connects the second port B to the first port A. The oil in the rodless chamber 11 of the propulsion cylinder 1 returns oil through the control valve assembly 9, achieving smooth retraction of the propulsion cylinder 1.

[0060] According to embodiments of this disclosure, the two-way cartridge valve 2, the pressure reducing valve 7, the first check valve 8, and the second check valve 5 are all mounted on the same valve block. The valve block includes: a first oil passage 100, connecting the first interface A to the control valve assembly 9; a second oil passage 200, connecting the second interface B to the first oil source 6; and a control oil passage 300, connecting the control chamber 10 to the second interface B. The pressure reducing valve 7 and the first check valve 8 are connected in series between the control oil passage 300 and the first oil passage 100, and the second check valve 5 is disposed in the second oil passage 200.

[0061] In some illustrative embodiments, the hydraulic system integrates a two-way cartridge valve 2, a pressure-reducing valve 7, a first check valve 8, and a second check valve 5 onto a single valve block. The components are connected via a first oil passage 100, a second oil passage 200, and a control oil passage 300 within the valve block. The pressure-reducing valve 7 and the first check valve 8 are connected in series between the control oil passage 300 and the first oil passage 100, while the second check valve 5 is located in the second oil passage 200. This integrated design reduces external piping and joints, lowers the risk of leakage, and improves system sealing reliability and contamination resistance. Simultaneously, the compact oil passage layout shortens the pressure transmission path between the control chamber 10 and the second interface B, as well as the venting path from the control chamber 10 to the first interface A via the pressure-reducing valve 7 and the first check valve 8, thereby improving system response speed.

[0062] According to an embodiment of this disclosure, the hydraulic system further includes a first damping orifice 4, one end of which is connected to a second interface B, and the other end of which is connected to a control chamber 10. The first damping orifice 4 is configured to form a pressure difference between the second interface B and the control chamber 10 when oil returns to the control chamber 10.

[0063] In some illustrative embodiments, the first damping orifice 4 is disposed between the second interface B and the control chamber 10, and is connected in parallel in the control oil circuit between the control chamber 10 and the second interface B. When the control chamber 10 is depressurized to the first interface A via the pressure reducing valve 7 and the first check valve 8, the pressure drop rate in the control chamber 10 is faster than the pressure change in the second interface B due to the throttling effect of the parallel damping orifice. This creates a pressure difference where the pressure in the control chamber 10 is lower than the pressure in the second interface B, providing additional upward opening force for the valve core of the two-way cartridge valve 2, ensuring that the valve core can be reliably and smoothly lifted in the push-back mode.

[0064] According to embodiments of this disclosure, the hydraulic system further includes a second damping orifice 3, which is connected in series between the control chamber 10 and the second interface B, and is configured to reduce vibration during the opening and closing of the insert of the two-way cartridge valve 2.

[0065] In some illustrative embodiments, the second damping orifice 3 is connected in series in the control oil circuit between the control chamber 10 and the second interface B. Its function is to absorb pressure fluctuation energy through a throttling effect during the opening and closing of the two-way cartridge valve 2, thereby effectively suppressing valve core vibration. Specifically, when the two-way cartridge valve 2 opens or closes, the pressure in the control chamber 10 undergoes transient changes. Without the damping orifice, the oil in the control oil passage 300 may experience pressure oscillations due to sudden pressure changes, causing the valve core to repeatedly impact the valve seat or valve cover, resulting in hydraulic shock and noise. The second damping orifice 3, by limiting the oil flow between the control chamber 10 and the second interface B, slows down the rate of pressure change in the control chamber 10, making the valve core movement smoother and less impactful. This not only reduces system vibration and noise during operation but also reduces wear between the valve core and valve seat, extending the service life of the two-way cartridge valve 2. Simultaneously, it avoids unexpected oil circuit interruptions caused by valve core vibration, further improving the stability and reliability of the hydraulic system.

[0066] According to embodiments of this disclosure, a tunnel boring machine (TBM) is provided, including a shield body and a hydraulic system as described in any of the above embodiments. A propulsion cylinder 1 of the hydraulic system is disposed on the shield body, and the piston rod of the propulsion cylinder 1 is configured to drive the shield body forward or to escape obstacles. A control valve group 9 of the hydraulic system is disposed in the control system of the shield body and is configured to control the extension and retraction of the propulsion cylinder 1 in propulsion mode. A first oil source 6 of the hydraulic system is configured to provide a pressure higher than that of a second oil source to the propulsion cylinder 1 in escape mode.

[0067] In some illustrative embodiments, the tunnel boring machine (TBM) integrates the aforementioned hydraulic system to achieve flexible switching between two operating modes: escape mode and normal propulsion. During normal tunneling, control valve group 9 controls propulsion cylinder 1 to drive the shield body forward smoothly at conventional pressure (≤350 bar). When encountering a jam and needing to escape, the first oil source 6 provides ultra-high pressure (≥420 bar) hydraulic fluid. The two-way cartridge valve 2 in the hydraulic system automatically closes according to the pressure status, isolating the ultra-high pressure oil circuit from the normal propulsion oil circuit, protecting control valve group 9 and the second oil source from high pressure impact. Simultaneously, the ultra-high pressure hydraulic fluid enters the rodless chamber 11 of propulsion cylinder 1 through the second one-way valve 5, providing a powerful escape thrust. In the event of a power outage, the hydraulic system automatically achieves passive pressure maintenance in the rodless chamber to prevent the shield body from sliding backward due to external pressure. Furthermore, the hydraulic system adopts an integrated valve block structure, which helps reduce manufacturing costs and simplifies installation and maintenance. This TBM can achieve ultra-high pressure escape under complex geological conditions and also has the ability to passively maintain pressure during power outages, thereby improving operational safety and system reliability.

[0068] The embodiments of this disclosure have been described above. However, these embodiments are for illustrative purposes only and are not intended to limit the scope of this disclosure. Although various embodiments have been described above, this does not mean that the measures in the various embodiments cannot be used advantageously in combination. The scope of this disclosure is defined by the appended claims and their equivalents. Various substitutions and modifications can be made by those skilled in the art without departing from the scope of this disclosure, and all such substitutions and modifications should fall within the scope of this disclosure.

Claims

1. A hydraulic system, characterized in that, include: Hydraulic cylinder (1); The two-way cartridge valve (2) has a first interface, a second interface and a control chamber. The first interface is connected to the control valve group (9), the second interface is connected to the first oil source (6) and connected to the rodless chamber of the propulsion cylinder (1). The control chamber is connected to the second interface through the control oil circuit. The pressure of the first oil source (6) is configured to be greater than the pressure of the second oil source connected to the control valve group (9). Pressure reducing valve (7), the inlet of the pressure reducing valve (7) is connected to the control chamber, and the outlet of the pressure reducing valve (7) is connected to the first interface via the first check valve (8); The second check valve (5) is located between the first oil source (6) and the second port, and allows oil to flow from the first oil source (6) to the second port; When the hydraulic system is de-energized, the control valve group (9) closes to maintain pressure, and the pressure of the control chamber is balanced with that of the second interface, so that the two-way cartridge valve (2) is closed, cutting off the first interface from the second interface. The rodless chamber pressure of the propulsion cylinder (1) is maintained by the second check valve (5) and the two-way cartridge valve (2).

2. The hydraulic system according to claim 1, characterized in that, The pressure-bearing area of ​​the valve core control chamber end of the two-way cartridge valve (2) is configured to be greater than the pressure-bearing area of ​​the second interface end; Furthermore, the sum of the pressure-bearing area of ​​the first interface end and the pressure-bearing area of ​​the second interface end of the two-way cartridge valve (2) is equal to the pressure-bearing area of ​​the valve core control cavity end.

3. The hydraulic system according to claim 2, characterized in that, The ratio of the pressure-bearing area of ​​the valve core control chamber end to the pressure-bearing area of ​​the second interface end is 3:1; And / or, the ratio of the pressure-bearing area of ​​the first interface end to the pressure-bearing area of ​​the second interface end is 2:

1.

4. The hydraulic system according to claim 1, characterized in that, The set opening pressure threshold of the pressure reducing valve (7) is configured to be less than the first pressure of the first oil source (6), less than the second pressure of the second oil source, and less than the rated pressure of the control valve group (9).

5. The hydraulic system according to claim 4, characterized in that, The first pressure is configured to be greater than or equal to 420 bar; And / or, the second pressure is configured to be less than or equal to 350 bar.

6. The hydraulic system according to claim 4, characterized in that, The hydraulic system has an escape mode, a propulsion extension mode, and a propulsion retraction mode; In the escape mode, the first oil source (6) is configured to supply oil to the second interface, the control chamber and the second interface have equal pressure, and the two-way cartridge valve (2) cuts off the first interface and the second interface through the pressure-bearing area difference of the valve core; In the propulsion extension mode, the control valve group (9) is configured to supply oil to the first interface, the pressure of the control chamber is released through the pressure reducing valve (7) and the first check valve (8), and the two-way cartridge valve (2) connects the first interface with the second interface so that the oil from the second oil source enters the rodless chamber of the propulsion cylinder (1); In the propulsion retraction mode, the control valve group (9) connects the first interface to return oil, the pressure in the control chamber is released through the pressure reducing valve (7) and the first one-way valve (8), and the two-way cartridge valve (2) connects the second interface to the first interface.

7. The hydraulic system according to claim 1, characterized in that, The two-way cartridge valve (2), the pressure reducing valve (7), the first check valve (8) and the second check valve (5) are all installed on the same valve block; The valve block contains: The first oil passage connects the first interface to the control valve group (9). The second oil passage connects the second interface to the first oil source (6). The control oil passage connects the control chamber to the second interface; The pressure reducing valve (7) and the first check valve (8) are connected in series between the control oil passage and the first oil passage, and the second check valve (5) is located in the second oil passage.

8. The hydraulic system according to claim 1, characterized in that, Also includes: A first damping orifice (4) is configured to form a pressure difference between the second interface and the control cavity when oil is circulated through the control cavity. One end of the first damping orifice (4) is connected to the second interface, and the other end of the first damping orifice (4) is connected to the control cavity.

9. The hydraulic system according to claim 1, characterized in that, Also includes: The second damping orifice (3), which is connected in series in the oil passage between the control cavity and the second interface, is configured to reduce vibration during the opening and closing of the insert of the two-way cartridge valve (2).

10. A tunnel boring machine, characterized in that, include: shield; The hydraulic system as described in any one of claims 1 to 9; The propulsion cylinder (1) of the hydraulic system is disposed on the shield body, and the piston rod of the propulsion cylinder (1) is configured to drive the shield body forward or to escape from a tangled situation; The control valve group (9) of the hydraulic system is located in the control system of the shield body and is configured to control the extension and retraction of the propulsion cylinder (1) in the propulsion mode; The first oil source (6) of the hydraulic system is configured to provide a higher pressure to the propulsion cylinder (1) than the second oil source in the escape mode.

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