Shield tail sealing brush structure and shield tail structure of shield tunneling machine
By incorporating an outer protective plate, a middle protective plate, and an inner protective plate, along with a steel wire layer, an arc-shaped surface, and decreasing grease pressure into the shield tail sealing brush structure, the problems of shield tail brush wear and bending are solved, achieving a shield tail brush design with high-efficiency sealing and long service life, suitable for construction in complex geological formations.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- CHINA RAILWAY 11TH BUREAU GRP CORP LTD
- Filing Date
- 2025-06-17
- Publication Date
- 2026-04-21
AI Technical Summary
The shield tail brush experiences increased wear in long-distance, deep-buried, and high-water-pressure strata, leading to frequent bending, easy failure, and safety hazards. In particular, in soft strata, the shield body retreats frequently, increasing friction and affecting the sealing effect.
A shield tail sealing brush structure is designed, including an outer protective plate, a middle protective plate, and an inner protective plate, as well as a steel wire layer, forming a double-seal structure. An arc-shaped curved surface is set at the root of the tail brush to reduce friction. Combined with the multiple shield tail brushes and the decreasing grease pressure in the filling chamber, an adaptive dynamic seal is achieved.
It improves the wear resistance and sealing reliability of the tail brush, extends its service life, reduces maintenance costs, adapts to complex geological conditions, and enhances construction safety and continuity.
Smart Images
Figure CN224149563U_ABST
Abstract
Description
Technical Field
[0001] This utility model belongs to the technical field of shield tunneling construction, and specifically relates to a shield tail sealing brush structure and a shield tail structure of a tunnel boring machine. Background Technology
[0002] During tunnel boring machine (TBM) construction, the tail brush is a crucial sealing component that prevents groundwater and synchronous grout from seeping into the tunnel and isolates the external strata from the tunnel interior. However, in long-distance, deep-buried, and high-water-pressure strata, the tail brush experiences accelerated wear as the TBM advances. Furthermore, with increasing depth, the pressure required to balance the tunnel face gradually increases, and according to the law of action and reaction forces, the shield also experiences a reaction force. Under this reaction force, when the TBM completes tunneling and performs segment assembly and hydraulic jack retrieval, the shield may retract. This retraction is particularly frequent in soft strata due to increased soil pressure, and it causes the tail brush to retract as well, leading to increased friction between the tail brush and the outer arc of the tunnel segments.
[0003] When the outer arc of the tunnel segment is uneven or the outer arc surface is not smooth, especially when the tail brush retracts and passes through the splice seam of two adjacent tunnel segments, the tail brush will bend in the opposite direction due to the force. Frequent bending will cause the tail brush to fatigue and damage, eventually leading to the failure of the shield tail seal, which poses a great safety hazard. Utility Model Content
[0004] This utility model provides a tail shield sealing brush structure and a shield machine tail shield structure to solve the problems of frequent bending, wear, and easy failure of the tail shield brush.
[0005] To solve the above-mentioned technical problems, the technical solution adopted by this utility model is as follows:
[0006] On the one hand, this application provides a shield tail sealing brush structure, including a shield tail brush, the shield tail brush including a tail brush head and a tail brush root connected as one piece, the tail brush head is used to be fixed to the shield machine, and the tail brush root is used to contact the surface of the tunnel segment.
[0007] The shield tail brush includes an outer protective plate and an inner protective plate, and the outer protective plate has an arc-shaped curved surface on the side away from the head of the tail brush.
[0008] A middle protective plate is also provided between the inner protective plate and the outer protective plate, and a steel wire layer is provided in the area between the outer protective plate and the middle protective plate as well as in the area between the middle protective plate and the inner protective plate.
[0009] Furthermore, the tail brush root includes a straight section and a bent section, and the arcuate surface is formed at the connection between the straight section and the bent section.
[0010] Furthermore, the root of the tail brush is bent counterclockwise relative to the head of the tail brush, the bent section is bent clockwise relative to the straight section, and the arc-shaped surface is used to abut against the surface of the tube segment.
[0011] Furthermore, the outer protective plate (13) comprises two layers of 1.0mm thick spring plates plus three layers of 0.6mm thick spring plates; the inner protective plate (14) comprises two layers of 1.0mm thick spring plates.
[0012] Furthermore, the middle protective plate includes a 1.0mm thick spring plate.
[0013] Furthermore, the steel wire layer wraps around the periphery of the middle protective plate, and the middle protective plate and the steel wire layer can be removed together.
[0014] Furthermore, the outer protective plate is made of an arc-shaped steel plate that matches the outer arc of the pipe segment along the circumference of the pipe segment.
[0015] On the other hand, this application provides a shield tail structure for a tunnel boring machine, including a shield tail, wherein multiple shield tail brushes are arranged at intervals along the tunneling direction on the periphery of the shield tail, and a filling chamber is formed between adjacent shield tail brushes, wherein the filling chamber is filled with shield tail grease.
[0016] Furthermore, the grease filling pressure in the different filling chambers is different.
[0017] Furthermore, along the tunneling direction, the shield tail grease filling pressure in each of the filling chambers decreases step by step.
[0018] The present invention can achieve the following beneficial effects:
[0019] (1) The shield tail brush is provided with an arc-shaped curved surface on the outer protective plate so that the shield tail brush and the outer arc surface of the tube segment form a tangential surface contact, which reduces the friction between the root of the tail brush and the outer arc surface of the tube segment, reduces the concentration of frictional stress, avoids the tail brush being subjected to concentrated force and frequently bending and breaking in the reverse direction during retraction, thereby improving the service life of the shield tail brush and ensuring the sealing effect.
[0020] (2) The tail brush is equipped with an outer protective plate, a middle protective plate and an inner protective plate, and a steel wire layer is wrapped around the middle protective plate to divide the original single tail brush into two tail brushes, forming a double-sealed structure to improve the friction resistance and water pressure resistance.
[0021] (3) Multiple shield tail brushes are set along the tunneling direction. If one of the shield tail brushes is damaged, it can be replaced without affecting the sealing effect. At the same time, the design of the shield tail brushes allows each layer of protective plate and steel wire layer to be replaced separately, reducing maintenance costs. Attached Figure Description
[0022] The present invention will be further described below with reference to the accompanying drawings and embodiments:
[0023] Figure 1 This is a schematic diagram of a shield tail sealing brush structure according to the present invention;
[0024] Figure 2 This is a schematic diagram illustrating the internal structure of the shield tail brush of this utility model;
[0025] Figure 3 This is a plan view of the shield tail during tunneling of the present invention;
[0026] Figure 4 for Figure 3 Enlarged view of point A in the middle.
[0027] The attached diagram lists the components represented by each number as follows:
[0028] 1. Tail brush; 11. Tail brush head; 12. Tail brush root; 121. Straight section; 122. Bending section; 13. Outer protective plate; 131. Arc-shaped surface; 14. Inner protective plate; 15. Middle protective plate; 16. Steel wire layer;
[0029] 2. Shield tail; 21. Filling chamber;
[0030] 100, tunnel segments; 200, tunnel boring machine. Detailed Implementation
[0031] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present utility model. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present utility model belong to the present utility model.
[0032] Furthermore, the described features, structures, or characteristics can be combined in any suitable manner in one or more embodiments. Numerous specific details are provided in the following description to give a thorough understanding of embodiments of this application. However, those skilled in the art will recognize that the technical solutions of this application can be practiced without one or more of the specific details, or other methods, components, apparatuses, steps, etc., can be employed. In other instances, well-known methods, apparatuses, implementations, or operations are not shown or described in detail to avoid obscuring various aspects of this application.
[0033] like Figures 1 to 4As shown, a shield tail sealing brush structure includes a shield tail brush 1, which includes a tail brush head 11 and a tail brush root 12 connected as one piece. The tail brush head 11 is fixed to the shield tail 2 of the tunnel boring machine 200 by high-strength bolts. The tail brush root 12 is used to contact the outer arc surface of the tunnel segment 100. By the tight contact between the tail brush root 12 and the tunnel segment 100, the sealing of groundwater and synchronous grouting slurry is achieved.
[0034] The tail shield brush 1 includes an outer protective plate 13, a middle protective plate 15, and an inner protective plate 14 arranged sequentially. The areas between the outer protective plate 13 and the middle protective plate 15, as well as the areas between the middle protective plate 15 and the inner protective plate 14, are filled with a steel wire layer 16. The steel wire layer 16 wraps around the middle protective plate 15. The steel wire layer 16 is used to isolate the middle protective plate 15 and the inner protective plate 14, as well as to isolate the middle protective plate 15 and the outer protective plate 13. In addition, the middle protective plate 15 and the steel wire layer 16 can be removed together.
[0035] The shield tail sealing brush structure of this embodiment adds a middle protective plate 15 in the middle of the traditional single tail brush. That is, the shield tail sealing brush structure of this utility model adopts the design of outer protective plate 13 + steel wire layer 16 + middle protective plate 15 + steel wire layer 16 + inner protective plate 14, which divides the original single tail brush into two tail brushes to form a double sealing structure, thereby improving the anti-friction and anti-water pressure ability of the shield tail brush 1, and reducing the probability of sealing failure at the shield tail brush 1.
[0036] Specifically, the outer protective plate 13 comprises two layers of 1.0mm thick spring plates and three layers of 0.6mm thick spring plates, the middle protective plate 15 comprises one layer of 1.0mm thick spring plate, and the inner protective layer comprises two layers of 1.0mm thick spring plates. The outer protective plate 13 is made of an arc-shaped steel plate that matches the outer arc of the segment 100 along its circumference. The steel plate is made of 65Mn with a hardness of HRC43-48 and is formed by CNC bending process to ensure a fit of ≥95% with the segment 100.
[0037] Furthermore, the wire brush inside the wire layer 16 is made of corrosion-resistant stainless steel wire with a diameter of 0.35mm, and the spring plate is treated with anti-rust to improve fatigue resistance and corrosion resistance.
[0038] This invention, by forming a layered steel plate structure, increases the sealing pressure resistance of the tail brush 1 to 12 bar, making it suitable for ultra-high water pressure formations. Simultaneously, when the outer protective plate 13 wears, the middle protective plate 15 provides further protection, thus offering secondary protection and extending the lifespan of the tail brush 1. Furthermore, the structural design of the tail brush 1 in this invention allows for the individual replacement of the protective plate or the steel wire layer 16 when the tail brush 1 is damaged, reducing maintenance costs.
[0039] The outer protective plate 13 also has an arc-shaped curved surface 131 on the side away from the tail brush head 11. Specifically, the tail brush root 12 includes a straight section 121 and a bent section 122. The tail brush root 12 is bent counterclockwise relative to the tail brush head 11, while the bent section 122 is bent clockwise relative to the straight section 121. The arc-shaped curved surface 131 is formed at the connection between the straight section 121 and the bent section 122 for contacting the surface of the tube 100.
[0040] The bending radius of the arc surface 131 is 10mm and the bending length is 35mm. By processing the tail brush root 12 into an arc structure, the tail brush root 12 and the outer arc surface of the tube 100 form a tangential surface contact, which reduces the friction between the tail brush root 12 and the outer arc surface of the tube 100, reduces the concentration of frictional stress, and avoids the tail brush from being frequently bent and broken due to concentrated force during retraction.
[0041] In addition, this application also provides a shield tail structure for a tunnel boring machine, including a shield tail 2. Multiple shield tail brushes 1 are arranged at intervals along the tunneling direction on the periphery of the shield tail 2. A filling chamber 21 is formed between adjacent shield tail brushes 1. The filling chamber 21 is filled with shield tail grease, and the filling pressure of shield tail grease in different filling chambers 21 is different.
[0042] Specifically, taking the setting of four filling chambers 21 as an example, according to the design characteristics of the filling chambers 21, it is necessary to make precise control based on factors such as geological conditions, propulsion speed, and equipment parameters. The grease injection pressure gradient of each chamber is set according to the grouting pressure. Usually, the pressure of the P4 filling chamber 21, that is, the outermost filling chamber 21, needs to be 2 bar higher than the grouting pressure. The pressure of the P3 filling chamber 21 is 0.5 bar lower than the P4 filling chamber 21. The pressure of the P2 filling chamber 21 is 0.5 bar lower than the P3 filling chamber 21. The pressure of the P1 filling chamber 21 is further reduced by 0.5 bar, that is, P4 = P3 + 0.5 = P2 + 1 = P1 + 1.5.
[0043] The aforementioned grease injection pressure is automatically cyclically controlled by the shield machine 200 PLC to ensure stable pressure in each filling chamber 21 and uniform injection in each path, preventing grout leakage at the tail of the shield 2. The purpose is to perform layered and graded pressure injection based on the arrangement of each sealing chamber and the ground pressure, forming a stepped pressure from the inside to the outside and using the pressure difference to achieve adaptive dynamic sealing.
[0044] In summary, this utility model provides a tail shield sealing brush structure and a shield machine tail shield structure. The tail shield sealing brush structure includes a tail brush head 11 and a tail brush root 12 connected as one piece, and is provided with an outer protective plate 13, a middle protective plate 15, and an inner protective plate 14. Steel wire layers 16 are provided between the outer protective plate 13 and the middle protective plate 15, and between the middle protective plate 15 and the inner protective plate 14, forming a structural arrangement with layered buffering and multi-level sealing functions. This utility model, through the arc-shaped tail brush structure and the setting of multiple elastic protective plates, not only significantly improves the wear resistance and sealing reliability of the tail shield brush 1 under high-pressure tunneling environments, but also effectively disperses frictional loads and delays fatigue failure through the double barrier structure constructed by the middle protective plate 15 and the steel wire layers 16, improving the overall structure's adaptability to complex geological conditions such as long distances, deep burial depths, and high water pressure. Furthermore, by arranging multiple tail brushes 1 at intervals around the tail 2 in the tunneling direction, forming a filling chamber 21 between adjacent brushes, and applying decreasing tail grease pressure, an adaptive dynamic sealing effect is further achieved, enhancing the safety and continuity of the tunnel boring machine construction process.
[0045] The technical solution of this utility model has advantages such as reasonable structure, convenient maintenance and strong sealing stability. It can significantly extend the service life of the shield tail sealing component, reduce construction risks and maintenance costs, and is suitable for the urgent needs of high sealing reliability and adaptability to complex strata in current shield construction. It has broad prospects for engineering promotion and application and industry value.
[0046] The above embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it. Under the concept of this utility model, the technical features of the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other variations of different aspects of this utility model as described above. For the sake of brevity, they are not provided in detail. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this utility model.
Claims
1. A tail seal brush structure, characterized by: Includes a tail brush (1), the tail brush (1) includes a tail brush head (11) and a tail brush root (12) connected as one piece, the tail brush head (11) is used to be fixed to the tunnel boring machine (200), and the tail brush root (12) is used to contact the surface of the tunnel segment (100); The shield tail brush (1) includes an outer protective plate (13) and an inner protective plate (14). The outer protective plate (13) has an arc-shaped curved surface (131) on the side away from the tail brush head (11). A middle protective plate (15) is also provided between the inner protective plate (14) and the outer protective plate (13). A steel wire layer (16) is provided in the area between the outer protective plate (13) and the middle protective plate (15) and in the area between the middle protective plate (15) and the inner protective plate (14).
2. The tail seal brush structure of claim 1, wherein: The tail brush root (12) includes a straight section (121) and a bent section (122), and the arc-shaped surface (131) is formed at the junction of the straight section (121) and the bent section (122).
3. The tail seal brush structure of claim 2, wherein: The root (12) of the tail brush is bent counterclockwise relative to the head (11) of the tail brush, the bent section (122) is bent clockwise relative to the straight section (121), and the arc-shaped surface (131) is used to abut against the surface of the tube segment (100).
4. The tail seal brush structure of claim 1, wherein: The outer protective plate (13) comprises two layers of 1.0mm thick spring plates plus three layers of 0.6mm thick spring plates; the inner protective plate (14) comprises two layers of 1.0mm thick spring plates.
5. The shield tail sealing brush structure according to claim 1, characterized in that: The middle protective plate (15) includes a 1.0mm thick spring plate.
6. The tail seal brush structure of claim 1, wherein: The steel wire layer (16) wraps around the periphery of the middle protective plate (15), and the middle protective plate (15) and the steel wire layer (16) can be removed together.
7. The tail seal brush structure of claim 1, wherein: The outer protective plate (13) is made of an arc-shaped steel plate that matches the outer arc of the segment (100) along the circumference of the segment (100).
8. A shield tail structure of a shield machine, characterized by: Includes a shield tail (2), and multiple shield tail brushes (1) as described in any one of claims 1-7 are arranged at intervals around the shield tail (2) along the tunneling direction. A filling chamber (21) is formed between adjacent shield tail brushes (1), and the filling chamber (21) is filled with shield tail grease.
9. The shield tail structure of claim 8, wherein: The pressure of the shield tail grease filling in the different filling chambers (21) is different.
10. A shield tail structure for a tunnel boring machine according to claim 9, characterized in that: Along the tunneling direction, the shield tail grease filling pressure in each of the filling chambers (21) decreases step by step.