Multi-channel continuous grease feeding device for tail seal of shield machine

Abstract

A multi-channel continuous grease supply device for the tail seal of a shield machine, through the coordinated work of multiple injection devices and standby injection devices, can automatically switch when any grease pump is insufficient or abnormal, ensuring uninterrupted grease supply and significantly reducing the risk of slurry leakage caused by tail seal grease interruption. The supply device uses a large grease tank instead of the traditional small barrel grease supply mode, which can store a large amount of grease at one time, reduce the construction interruption and labor caused by frequent replacement of grease barrels, and improve the continuity of shield tunneling. The injection device and the supply device are independently arranged, compact in structure, and easy to install and maintain in the narrow space of the shield machine; the large tank supports integral lifting, improving the replacement efficiency.

Description

Technical Field

[0001] This utility model relates to the field of shield tunnel sealing grease pumping technology, specifically a multi-channel continuous grease supply device for the tail seal of a shield machine. Background Technology

[0002] In the field of tunnel boring machine (TBM) construction, the tail seal performance plays a crucial role in ensuring construction safety and quality. As a key component in maintaining the tail seal performance, the rationality and reliability of the tail seal grease injection system directly affect the overall operation of the TBM. Currently, most existing shield tail seal grease injection systems use multiple barrel-type grease pumps to supply grease to each grease chamber. While this traditional grease supply system is relatively simple in structure, it has revealed a series of shortcomings that urgently need to be addressed in practical applications: First, the grease supply relies on individual barrels of grease. When one barrel is depleted, manual barrel replacement, manual venting, and restarting of the pumping system are required. In the demanding environment of shield machine construction, this is cumbersome, occupies construction space, and reduces construction efficiency. Second, the grease supply stability is poor. If one grease pump has insufficient oil or malfunctions, the corresponding grease chamber will experience a short-term grease shortage, leading to a drop in tail seal pressure, grout leakage, and other risks, threatening construction safety and stability. Third, the use of small grease tanks also presents problems. If manual replenishment is not timely after depletion, or if the pump is sucked into a vacuum or air is mixed in, it will cause a momentary interruption in grease supply, reducing sealing performance and affecting construction quality. How to solve the problem of multi-channel continuous grease supply for shield machine tail seals is an urgent issue to be addressed. Summary of the Invention

[0003] The purpose of this invention is to provide a multi-channel continuous grease supply device for the tail seal of a tunnel boring machine. The large grease container in the supply device can continuously and stably supply grease to the small grease containers of each injection device, thus solving the problems in the prior art.

[0004] The technical solution adopted by this utility model to solve its technical problem is: a multi-channel continuous grease supply device for the tail seal of a tunnel boring machine, including a replenishment device and several interconnected injection devices. The replenishment device includes a base plate, on which a large grease container and a support frame are provided. A replenishment pump is installed on the support frame. The suction port of the replenishment pump extends into the large grease container. A grease output main pipe is installed on the outlet of the replenishment pump. The grease output main pipe is connected to several grease output branch pipes. A switch valve is installed on each grease output branch pipe. Each grease output branch pipe is connected to an injection device. The injection device includes a movable plate, on which a small grease container is provided. A grease pump is installed in the small grease container. A grease injection pipeline is installed on the outlet of the grease pump. A PTC heater, a water bath circulation jacket, and a grease distribution valve group are provided on the grease injection pipeline. The grease output branch pipes are connected to the small grease container. A lifting cylinder is mounted on the support frame, with its piston rod fixed to the base plate. A vertically arranged guide cylinder is also provided on the base plate, and a guide rod that cooperates with the guide cylinder is provided on the support frame. The extension and retraction of the piston rod of the lifting cylinder can drive the large grease container to move vertically up and down relative to the supply pump. The bottom of the moving plate is equipped with casters, and a vertically movable anchoring electromagnet is also mounted on the moving plate. An injection hole is provided on the small grease container, and the grease output branch pipe is connected to the small grease container through the injection hole. A transparent observation window is also provided on the outer surface of the small grease container. The movable plate is equipped with a mounting bracket, on which a pneumatic control valve assembly and a pneumatic motor are mounted. A pneumatic control pipeline is connected between the pneumatic control valve assembly and the pneumatic motor. The pneumatic motor is connected to a grease pump through an air circuit. The pneumatic control valve assembly includes a connected air inlet pipe, an intermediate pipe, and an air delivery pipe. A miniature pressure pump and a flow meter are installed between the air inlet pipe and the intermediate pipe. A pressure reducing valve is installed between the intermediate pipe and the air delivery pipe. The pressure reducing valve includes a valve body. A signal feedback device is installed at the bottom of the valve body. A main valve core that can be vertically raised and lowered is installed inside the valve body. A piston is installed at the bottom of the main valve core. A spring is installed at the top of the main valve core. The spring always tends to push the main valve core downward. A moving iron core is fitted around the outer periphery of the main valve core. An electromagnetic coil is installed on the upper part of the valve body. When the electromagnetic coil is energized, it attracts the moving iron core to move upward and compresses the spring to move.

[0005] The positive effects of this utility model are as follows: The multi-channel continuous grease supply device for the tail seal of a tunnel boring machine (TBM) described herein, through the coordinated operation of multiple injection devices and a backup injection device, can automatically switch when any grease pump experiences insufficient or abnormal oil supply, ensuring uninterrupted grease supply and significantly reducing the risk of grout leakage caused by grease interruption at the tail seal. The supply device uses a large grease tank instead of the traditional small-bucket grease supply mode, allowing for the storage of a large amount of grease at once, reducing construction interruptions and manual labor caused by frequent grease tank replacements, and improving the continuity of TBM tunneling. The injection device and supply device are independently arranged, with a compact structure, facilitating installation and maintenance within the confined space of the TBM; the large tank supports overall hoisting, improving replacement efficiency.

[0006] The use of large grease containers for unified grease supply eliminates the cumbersome operations of frequent manual container changes, manual venting, and restarting of the pumping system, saving construction time and space and effectively improving the overall efficiency of tunnel boring machine (TBM) construction. The multi-channel continuous grease supply design ensures that even if one channel fails, others can continue to operate normally, preventing grease interruption in the corresponding grease chamber and effectively preventing risks such as tail seal pressure drop and grout leakage, thus ensuring construction safety and stability. The design, including a PTC heater and water bath circulation jacket, ensures grease is pumped at an appropriate temperature, improving sealing performance. Simultaneously, a transparent observation window facilitates real-time monitoring of grease levels and timely replenishment, preventing sealing performance degradation due to grease supply interruptions. Attached Figure Description

[0007] Figure 1 This is a schematic diagram of the structure of this utility model; Figure 2 This is a schematic diagram of the injection device; Figure 3 yes Figure 2 Side view; Figure 4 yes Figure 2 A magnified view of part of I; Figure 5 This is a schematic diagram of the structure of a pneumatic control valve assembly; Figure 6 This is a simplified diagram illustrating the flow direction of oil when the grease distribution valve assembly is in operation. Detailed Implementation

[0008] This utility model describes a multi-channel continuous grease supply device for the tail seal of a tunnel boring machine, such as... Figure 1-4 As shown, the device includes a replenishment unit and several interconnected injection devices. The replenishment unit includes a base plate 1, on which a large grease container 2 and a support frame 3 are mounted. A replenishment pump 4 is installed on the support frame 3, and the suction port of the replenishment pump 4 extends into the large grease container 2. A grease output main pipe 5 is installed at the outlet of the replenishment pump 4. The grease output main pipe 5 is connected to several grease output branch pipes 6, and a switch valve 7 is installed on each grease output branch pipe 6. Each grease output branch pipe 6 is connected to an injection device.

[0009] The injection device includes a movable plate 8, on which a small grease container 9 is mounted. A grease pump 10 is installed inside the small grease container 9. A grease injection line 11 is installed at the output port of the grease pump 10. The grease injection line 11 is equipped with a PTC heater 12, a water bath circulation jacket 13, and a grease distribution valve assembly 14. A grease output branch pipe 6 is connected to the small grease container 9. The grease distribution valve assembly 14 can be the grease distribution valve assembly described in Chinese Patent Publication No. CN202421631836.7: An Automatically Lubricated Scraper Conveyor Sprocket Assembly.

[0010] The replenishment device can be installed on a supporting trolley behind the tunnel boring machine. A large grease container 2 is used for centralized storage of large-capacity grease and can be hoisted or replaced as a whole. A replenishment pump 4 is installed on a support frame 3, with its suction inlet extending to the bottom of the large grease container 2 to draw grease from the container. The support frame 3 forms the fixed skeleton of the replenishment pump 4. The outlet of the replenishment pump 4 is connected to the main grease output pipe 5, which connects to the small grease containers 9 of each injection device via various grease output branch pipes 6. Selective grease replenishment of each small grease container 9 is achieved through a switching valve 7. This replenishment device features large grease storage capacity, high replenishment efficiency, convenient replacement, and multi-point automatic grease replenishment, making it a crucial module for the continuous operation of multiple injection devices.

[0011] The grease distribution valve assembly 14 of the injection device can precisely distribute the high-pressure grease output from the grease pump 10 to multiple grease injection ports at the tail of the tunnel boring machine through multiple reversing valves and branches of the internal centralized distribution manifold. The grease pressure and flow rate of each branch can be independently adjusted to ensure uniform grease injection in each sealing area of ​​the tail, avoiding local seal failure due to insufficient grease injection. The valve assembly can be equipped with built-in pressure and flow sensors to feed back the grease injection status of each branch to the control system, realizing automated monitoring and fault early warning of tail grease injection.

[0012] Each injection device employs a multi-stage temperature control architecture. The grease sequentially passes through the preheating zone of the PTC heater 12 and the constant-temperature zone of the water bath circulation jacket 13. The PTC heater 12 can be connected in series between the grease container outlet and the inlet of the water bath circulation jacket 13, using a sleeve-type connection. The inner and outer tubes of the PTC heater 12 are coaxially arranged, and both ends are sealed by flange connections. Graphite gaskets are installed between the flanges to prevent leakage of the hot medium. The jacket body of the water bath circulation jacket 13 can be wrapped around the outside of the main oil supply pipeline, using a welded structure. The jacket shell is fixed to the main pipeline by a circumferential weld, forming a closed heating chamber. A temperature sensor can also be installed inside the pipeline, vertically mounted at the outlet pipeline of the water bath circulation jacket 13 via an insertion connector. The sensor probe extends into half the inner diameter of the pipeline to ensure full contact with the grease, enabling real-time monitoring and feedback of the grease temperature.

[0013] When using the device described in this utility model for grease supply, the flow rate of each injection pipeline is monitored by a flow meter. When the flow rate is abnormal, a grease replenishment operation is performed. The replenishment pump 4 is started, and its suction port extends deep into the large grease container 2, directly drawing grease from the bottom of the tank and transporting it through the grease output main pipe 5 to the target small grease container 9 with abnormal flow, ensuring that the inside of the tank is always free of air. The injection device at this location is started to draw grease, which is then heated by the PTC heater 12 and the water bath circulation jacket 13 to prevent pipeline blockage. After passing through the grease distribution valve group 14, the grease is distributed and delivered to multiple grease injection ports at the tail of the tunnel boring machine. Once the grease capacity in the small grease container 9 returns to full capacity, the replenishment pump 4 is stopped, and the switch valve 7 is closed, ending the grease replenishment process.

[0014] Furthermore, to facilitate the vertical movement of the large grease container 2 and ensure automatic alignment of the suction inlet of the replenishment pump 4 with the container opening during grease tank replacement, a lifting cylinder 15 is installed on the support frame 3. The piston rod of the lifting cylinder 15 is fixed to the base plate 1, and a vertically arranged guide cylinder 16 is also provided on the base plate 1. A guide rod 17 that cooperates with the guide cylinder 16 is provided on the support frame 3. The extension and retraction of the piston rod of the lifting cylinder 15 can drive the large grease container 2 to move vertically up and down relative to the replenishment pump 4. During subsequent continuous grease supply, if the grease level in the large grease container 2 drops, the retraction of the piston rod of the lifting cylinder 15 can cause the grease suction pipe of the replenishment pump 4 to extend below the grease level in the large grease container 2, ensuring good contact between the suction inlet and the grease surface and guaranteeing normal grease supply.

[0015] Furthermore, in order to enable the movement and positioning of each injection device, the bottom of the moving plate 8 is provided with casters 18, and a vertically lifting anchoring electromagnet 19 is also installed on the moving plate 8. The casters 18 facilitate pushing the injection device to a designated position. When it is necessary to fix the injection device in a certain position, the anchoring electromagnet 19 can be controlled to descend vertically to contact the steel plate ground. After being energized, the injection device can be fixed on the ground.

[0016] To connect the supply device with each injection device, the small grease container 9 is provided with an injection hole 20, and the grease output branch pipe 6 is connected to the small grease container 9 through the injection hole 20. Furthermore, to allow operators to monitor the grease content in the small grease container 9 in a timely manner, so as to replenish it promptly or end the grease injection after replenishment, a transparent observation window 21 is provided on the outer surface of the small grease container 9. The amount of grease in the small grease container 9 can be observed in real time through the observation window 21. During the grease injection process, when the grease level in the target small grease container 9 is observed to return to full capacity, the valve can be closed in a timely manner to end the grease replenishment process.

[0017] Furthermore, the movable plate 8 is provided with a mounting bracket 22, and the mounting bracket 22 is provided with a pneumatic control valve assembly 23 and a pneumatic motor 24, such as... Figure 5 As shown, a pneumatic control pipeline 25 is provided between the pneumatic control valve group 23 and the pneumatic motor 24, and the pneumatic motor 24 is connected to the grease pump 10 through the air passage.

[0018] The pneumatic control valve assembly 23 includes an inlet pipe 26, an intermediate pipe 27, and an outlet pipe 28 that are connected to each other. A miniature pressure pump 29 and a flow meter 30 are provided between the inlet pipe 26 and the intermediate pipe 27. A pressure reducing valve is provided between the intermediate pipe 27 and the outlet pipe 28. The pressure reducing valve includes a valve body 31. A signal feedback device 32 is provided at the bottom of the valve body 31. A main valve core 33 that can be vertically raised and lowered is provided inside the valve body 31. A piston 34 is provided at the bottom of the main valve core 33. A spring 35 is provided at the top of the main valve core 33. The spring 35 always has the tendency to push the main valve core 33 downward. A moving iron core 36 is fitted around the outer periphery of the main valve core 33. An electromagnetic coil 37 is provided on the upper part of the valve body 31. When the electromagnetic coil 37 is energized, it attracts the moving iron core 36 to move upward and compresses the spring 35 to move, thereby controlling the opening degree of the piston 34 and realizing the control of the air delivery volume and air delivery rate.

[0019] The pneumatic control valve assembly 23 can integrate a filter to remove moisture, oil, and impurities from the compressed air, preventing component wear or blockage. It can also be equipped with a pressure reducing valve to adjust the input compressed air pressure to the stable range required by the grease pump, typically 3-5 bar, ensuring stable operating pressure for the pneumatic motor and plunger pump, thereby controlling the grease pump's flow rate and pressure. The compressed air flow direction can be switched according to system commands or manual operation to start and stop the grease pump, as well as adjust the grease injection pressure and flow rate. The grease injection frequency and dosage can be adjusted when the tunnel boring machine's speed changes.

[0020] The multi-channel continuous grease supply device for the tail seal of a tunnel boring machine (TBM) as described in this invention comprises a replenishment device, multiple injection devices, a grease distribution valve group 14, a pneumatic control valve group 23, and a dynamic temperature-controlled viscosity stabilization module. The replenishment device is mounted on the rear trolley of the TBM and selectively replenishes grease to the small grease containers 9 of each injection device via a switching valve 7, achieving large-capacity centralized grease storage and multi-point automatic grease replenishment. The injection device consists of a grease pump 10, small grease containers 9, a PTC heater 12, a water bath circulation jacket 13, and high-pressure grease injection pipelines, capable of stably delivering high-pressure grease to the front, middle, and rear grease chambers of the tail. The grease distribution valve group 14 adopts a centralized distribution manifold structure, allowing independent adjustment of pressure and flow rate for multiple grease injection branches, and enabling multi-point monitoring and automated early warning through sensors. The system's supporting dynamic viscosity control module preheats and maintains a constant temperature for the grease, effectively avoiding clogging problems caused by low-temperature, high-viscosity conditions. This invention enables a continuous, uniform, and stable supply of sealing grease to the tail of the shield, reduces the need for manual replacement of grease tanks, improves the reliability of grease injection, reduces the risk of grout leakage, and is suitable for shield tunneling under long-distance and complex geological conditions.

[0021] The technical solution of this utility model is not limited to the scope of the embodiments described herein. All technical contents not described in detail herein are publicly known technologies.

Claims

1. A multi-channel continuous grease supply device for the tail seal of a tunnel boring machine, characterized in that: It includes a supply device and several interconnected injection devices. The supply device includes a base plate (1), on which a large grease container (2) and a support frame (3) are mounted. A supply pump (4) is installed on the support frame (3). The suction port of the supply pump (4) extends into the large grease container (2). A grease output main pipe (5) is installed on the discharge port of the supply pump (4). The grease output main pipe (5) is connected to several grease output branch pipes (6). A switch valve (7) is installed on the grease output branch pipes (6). Each grease output branch pipe (6) is connected to the injection device. The injection device includes a movable plate (8), a small grease container (9) is provided on the movable plate (8), a grease pump (10) is installed in the small grease container (9), and a grease injection pipeline (11) is installed on the output port of the grease pump (10). The grease injection pipeline (11) is provided with a PTC heater (12), a water bath circulation jacket (13) and a grease distribution valve group (14). The grease output branch pipe (6) is connected to the small grease container (9).

2. The multi-channel continuous grease supply device for the tail seal of a tunnel boring machine according to claim 1, characterized in that: A lifting cylinder (15) is installed on the support frame (3). The piston rod of the lifting cylinder (15) is fixed on the base plate (1). A vertically arranged guide cylinder (16) is also provided on the base plate (1). A guide rod (17) that cooperates with the guide cylinder (16) is provided on the support frame (3). The extension and retraction of the piston rod of the lifting cylinder (15) can drive the large oil container (2) to move vertically relative to the supply pump (4).

3. A multi-channel continuous grease supply device for the tail seal of a tunnel boring machine according to claim 1, characterized in that: The bottom of the movable plate (8) is provided with casters (18), and an anchoring electromagnet (19) that can be raised and lowered vertically is also installed on the movable plate (8).

4. A multi-channel continuous grease supply device for the tail seal of a tunnel boring machine according to claim 1, characterized in that: The small oil container (9) is provided with an injection hole (20), and the oil output branch pipe (6) is connected to the small oil container (9) through the injection hole (20). A transparent observation window (21) is also provided on the outer surface of the small oil container (9).

5. A multi-channel continuous grease supply device for the tail seal of a tunnel boring machine according to claim 1, characterized in that: The movable plate (8) is provided with a mounting bracket (22), on which a pneumatic control valve assembly (23) and a pneumatic motor (24) are provided. A pneumatic control pipeline (25) is provided between the pneumatic control valve assembly (23) and the pneumatic motor (24). The pneumatic motor (24) is connected to the grease pump (10) through an air passage. The pneumatic control valve assembly (23) includes a connected air inlet pipe (26), an intermediate pipe (27), and an air delivery pipe (28). A miniature pressure pump (29) and a flow meter (30) are provided between the air inlet pipe (26) and the intermediate pipe (27). The intermediate pipe (27) and the air delivery pipe (28) are connected. A pressure reducing valve is provided between the valve body (31) and the valve body (31) has a signal feedback device (32) at the bottom. A main valve core (33) that can be vertically raised and lowered is provided inside the valve body (31). A piston (34) is provided at the bottom of the main valve core (33). A spring (35) is provided at the top of the main valve core (33). The spring (35) always has the tendency to push the main valve core (33) down. A moving iron core (36) is fitted around the outer periphery of the main valve core (33). An electromagnetic coil (37) is provided on the upper part of the valve body (31). When the electromagnetic coil (37) is energized, it attracts the moving iron core (36) to move up and compresses the spring (35) to move.

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