A wear-resistant layer structure for a hard rock tunneling machine cutter head
Patent Information
- Application Number
- CN202522354221.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-11-06
- Publication Date
- 2026-09-18
- Estimated Expiration
- 2035-11-06
AI Technical Summary
[0002]目前，硬岩掘进机作为隧道、矿道等地下工程的核心装备，其刀盘直接与高强度、高硬度的岩石接触，承受高频冲击、剧烈摩擦与高温载荷，因此刀盘表面的耐磨层是保障掘进效率、延长刀盘服役寿命的关键结构，然而，当前硬岩掘进机刀盘耐磨层技术仍存在多方面缺陷，难以适配复杂硬岩掘进工况的需求
通过采用Fe-Cr-C系铁基合金作为金属连接层，并用热压方式连接刀盘钢基体与导电监测层，能有效降低不同材料层间的热膨胀系数差异，减少界面应力，避免层间剥离，提升整体结构的结合强度和服役稳定性；从内到外依次设置金属连接层、梯度氧化层、导电监测层和耐磨表层，使各层分别承担连接、过渡、监测和耐磨的核心功能。
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Figure CN224770197U_ABST
Abstract
Description
Technical Field
[0001] This utility model belongs to the field of wear-resistant technology for tunneling machine cutterheads, and particularly relates to a wear-resistant layer structure for hard rock tunneling machine cutterheads. Background Technology
[0002] Currently, hard rock tunnel boring machines (TBMs) are core equipment for underground engineering projects such as tunnels and mines. Their cutterheads come into direct contact with high-strength and high-hardness rocks and are subjected to high-frequency impacts, intense friction, and high-temperature loads. Therefore, the wear-resistant layer on the surface of the cutterhead is a key structure to ensure tunneling efficiency and extend the service life of the cutterhead. However, the current wear-resistant layer technology for hard rock TBM cutterheads still has many shortcomings and is difficult to adapt to the needs of complex hard rock tunneling conditions.
[0003] Currently, there is no effective online monitoring method for the wear layer of the cutterhead. The wear level can only be judged by periodic shutdown and disassembly inspection or by the experience of operators. If the inspection interval is too long, the steel substrate of the cutterhead may be exposed due to complete wear of the wear layer, causing irreversible damage to the substrate. If the inspection is too frequent, the tunneling operation will be interrupted, increasing the construction cycle and labor costs.
[0004] There is an urgent need for improvement, so we propose a wear-resistant layer structure for the cutterhead of a hard rock tunnel boring machine. Utility Model Content
[0005] The purpose of this invention is to address the aforementioned technical problems by providing a wear-resistant layer structure for the cutterhead of a hard rock tunnel boring machine, thereby achieving the effect of monitoring the condition of the cutterhead.
[0006] In view of this, the present invention provides a wear-resistant layer structure for the cutterhead of a hard rock tunnel boring machine, comprising: The cutter head steel substrate has a metal connecting layer on its outer side; A gradient oxide layer is disposed outside the metal interconnect layer; A conductivity monitoring layer is disposed outside the gradient oxide layer; A zoned gradient thickness wear-resistant surface layer is disposed on the outermost side of the cutterhead steel substrate. The metal connection layer is integrally formed from an Fe-Cr-C iron-based alloy, and the metal connection layer is connected to the cutter head steel substrate and the conductive monitoring layer by hot pressing.
[0007] Furthermore, the total thickness of the gradient oxide layer and the metal bonding layer is 200~500μm.
[0008] Furthermore, the conductive monitoring layer has a thickness of 50~100μm and is integrally formed from titanium carbide ceramic.
[0009] Furthermore, the surface of the conductive monitoring layer is also provided with a nickel foil electrode, the thickness of which is 5~10μm, and the nickel foil electrode is connected to the control system of the hard rock tunneling machine through a wire.
[0010] Furthermore, the partitioned gradient thickness wear-resistant surface layer includes: The edge area has a thickness of 15~20mm; The thickness of the area surrounding the tool is 10~15mm; The central area has a thickness of 5-8mm.
[0011] Furthermore, the outer surface of the partitioned gradient thickness wear-resistant surface layer is also coated with an aluminum nitride coating, the aluminum nitride coating having a thickness of 5~10μm, to improve the heat dissipation performance of the wear-resistant layer.
[0012] The beneficial effects of this utility model are: By using Fe-Cr-C iron-based alloy as the metal connecting layer and hot-pressing to connect the cutter head steel substrate and the conductive monitoring layer, the difference in thermal expansion coefficients between different material layers can be effectively reduced, interface stress can be reduced, interlayer delamination can be avoided, and the overall structural bonding strength and service stability can be improved. The metal connecting layer, gradient oxide layer, conductive monitoring layer and wear-resistant surface layer are set from the inside to the outside, so that each layer undertakes the core functions of connection, transition, monitoring and wear resistance respectively. Attached Figure Description
[0013] Figure 1 This is a schematic diagram of the overall structure of a wear-resistant layer structure for a cutterhead of a hard rock tunnel boring machine proposed in this utility model. The markings in the diagram are as follows: 1. Steel substrate of the cutter head; 2. Metal connection layer; 3. Gradient oxide layer; 4. Conductive monitoring layer; 42. Nickel foil electrode; 5. Partitioned gradient thickness wear-resistant surface layer; 51. Aluminum nitride coating. Detailed Implementation
[0014] The technical solutions of the embodiments of this application will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application are within the scope of protection of this application.
[0015] In the description of this application, it should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. For ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following drawings denote similar items; therefore, once an item is defined in one drawing, it need not be further discussed in subsequent drawings.
[0016] It should be noted that the terms "first," "second," etc., used in the specification and claims of this application are used to distinguish similar objects and not to describe a specific order or sequence. It should be understood that such use of data can be interchanged where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein, and the objects distinguished by "first," "second," etc., are generally of the same class and are not limited in number; for example, a first object can be one or more. Furthermore, in the specification and claims, "and / or" indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.
[0017] It should be noted that in the description of this application, the directional terms such as "front, back, up, down, left, right", "horizontal, vertical, horizontal" and "top, bottom" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description. Unless otherwise stated, these directional terms do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the scope of protection of this application. The directional terms "inner" and "outer" refer to the inner and outer contours relative to the outline of each component itself.
[0018] It should be noted that, in this application, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element. Furthermore, it should be noted that the scope of the methods and apparatuses in the embodiments of this application is not limited to performing functions in the order shown or discussed, but may also include performing functions substantially simultaneously or in the reverse order, depending on the functions involved. For example, the described methods may be performed in a different order than described, and various steps may be added, omitted, or combined. Additionally, features described with reference to certain examples may be combined in other examples.
[0019] Reference Figure 1 A wear-resistant layer structure for the cutterhead of a hard rock tunnel boring machine, comprising: The cutter head steel substrate 1 has a metal connecting layer 2 on its outer side; Gradient oxide layer 3 is disposed on the outside of metal connection layer 2; Conductivity monitoring layer 4 is disposed outside the gradient oxide layer 3; The partitioned gradient thickness wear-resistant surface layer 5 is set on the outside of the conductive monitoring layer 4 and the outermost side of the cutter head steel substrate 1. The metal connection layer 2 is integrally formed from Fe-Cr-C iron-based alloy, and the metal connection layer 2 is connected to the cutter head steel substrate 1 and the conductive monitoring layer 4 by hot pressing.
[0020] In this application, the Fe-Cr-C iron-based alloy powder and the cutterhead steel substrate 1 have similar compositions. During hot pressing, diffusion welding occurs, forming a metallurgical bonding interface. This effectively eliminates the difference in thermal expansion coefficients between the steel substrate and the outer layer material, avoiding interlayer delamination caused by temperature changes. The synergistic operation of the multi-layer functional chain ensures the stability of the inner layer structure from the cutterhead steel substrate 1 outwards. The gradient oxide layer 3 achieves a smooth transition of mechanical properties through composition gradient, alleviating the stress impact of the outer hard material. The conductive monitoring layer 4 can provide real-time feedback on the wear status. The zoned wear-resistant surface layer directly resists rock friction and impact. The four-layer structure sequentially transmits load, buffers stress, monitors status, and provides protection, forming a closed-loop functional system.
[0021] It needs to be explained that the gradient oxide layer 3 is a silicon carbide sheet, the nano-ceramic composite conductive monitoring layer 44 is titanium carbide ceramic, and the partitioned gradient thickness wear-resistant surface layer 5 is Cr20 high-chromium cast iron.
[0022] In the example of this application, the total thickness of the gradient oxide layer 3 and the metal bonding layer 2 is 200~500μm.
[0023] As a preferred example of this utility model, the gradient oxide layer 3 gradually increases in hardness from the inside to the outside, forming a hardness gradient with the metal connection layer 2 and the conductive monitoring layer 4. When the outer layer is subjected to impact load, the stress gradually decreases through the gradient layer, avoiding direct action on the steel substrate and causing brittle fracture. If the total thickness is less than 200μm and the thickness of the gradient oxide layer 3 is less than 80μm, the stress attenuation is insufficient and it is easy to cause interface cracking; if it is greater than 500μm, the self-weight of the transition layer increases by 1.2kg, which leads to an increase in the energy consumption of the cutterhead rotation. The range of 200~500μm can ensure the stress buffering effect while meeting the lightweight design requirements of the tunneling machine.
[0024] In the example of this application, the thickness of the conductive monitoring layer 4 is 50~100μm, and the conductive monitoring layer 4 is integrally formed from titanium carbide ceramic.
[0025] As a preferred example of this utility model, titanium carbide ceramic has both high hardness and stable conductivity. When used as a monitoring layer, it can withstand a certain degree of wear and can also provide feedback on the wear status through its own structural changes. When the wear-resistant surface wears down to the monitoring layer, the TiC grains are eroded, the integrity of the crystal structure is destroyed, and the resistance value increases linearly with the amount of wear. A thickness of 50~100μm ensures that the changes in electrical signals during the wear process are stable and controllable: if the thickness is <50μm, the wear is too fast and the monitoring cycle is too short; if it is >100μm, the electrical signal response to minor wear is lagging and cannot accurately capture the initial wear state. This thickness range can achieve a linear correlation of >95% between the wear amount and the electrical signal, which meets the monitoring accuracy requirements.
[0026] In the example of this application, the surface of the conductive monitoring layer 4 is also provided with a nickel foil electrode 42, the thickness of which is 5~10μm, and the nickel foil electrode 42 is connected to the control system of the hard rock tunneling machine through a wire.
[0027] As a preferred example of this utility model, a 5-10 μm thick nickel foil has high conductivity and flexibility. After being tightly attached to the upper and lower surfaces of the conductive monitoring layer 4, it can convert the resistance change of the monitoring layer into an electrical signal, which is transmitted to the control system through wires. The flexibility of the nickel foil ensures that it does not fall off when the cutter head vibrates, maintaining stable contact. The control system presets a resistance threshold. When the wear-resistant surface wears down to the monitoring layer and the resistance of the monitoring layer increases with the amount of wear and exceeds the threshold, the system triggers an early warning signal, and the operator can perform timely maintenance to avoid exposure and damage to the cutter head steel substrate 1.
[0028] In the example of this application, the partitioned gradient thickness wear-resistant surface layer 5 includes: The edge area has a thickness of 15~20mm; The thickness of the area surrounding the tool is 10~15mm; The central area has a thickness of 5-8mm.
[0029] As a preferred example of this utility model, when the cutterhead is working, the edge area has the highest linear velocity and the most intense impact friction with the rock; the area around the cutter has the second highest wear rate due to stress concentration caused by cutter installation; and the center area has the lowest linear velocity and the lowest wear rate. Therefore, a 15-20mm thick wear-resistant layer is provided in the edge area, 10-15mm in the area around the cutter, and 5-8mm in the center area, so that the life of each area matches its actual wear rate. By distributing the thickness as needed, compared with using a 15mm thick surface layer for the whole, material consumption can be reduced by 20%-30%, the weight of the cutterhead can be reduced, and premature local wear leading to the replacement of the whole cutterhead can be avoided, thus extending the cutterhead replacement cycle.
[0030] In the example of this application, the outer surface of the partitioned gradient thickness wear-resistant surface layer 5 is also coated with an aluminum nitride coating 51, the aluminum nitride coating 51 having a thickness of 5~10μm, to improve the heat dissipation performance of the wear-resistant layer.
[0031] As a preferred example of this utility model, a coating 5~10μm thick can quickly dissipate the heat generated by friction, reducing the working temperature of the wear-resistant surface by 40%~50%, and avoiding material oxidation and hardness reduction caused by high temperature; the aluminum nitride coating 51 forms a dense structure through physical vapor deposition, which can isolate oxygen, moisture and corrosive components in the air and rock debris, reduce chemical corrosion and erosion wear of the wear-resistant surface, and further extend its service life.
[0032] The embodiments of this application have been described above with reference to the accompanying drawings. Unless otherwise specified, the embodiments and features in the embodiments of this application can be combined with each other. This application is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of this application without departing from the spirit and scope of the claims, and all of these forms are within the protection scope of this application.
Claims
1. A wear layer structure for a hard rock tunneling machine cutter head, characterized by ,include: A steel substrate for the cutter head (1) is provided with a metal connecting layer (2) on the outer side of the steel substrate for the cutter head (1). A gradient oxide layer (3) is disposed on the outside of the metal connection layer (2); A conductivity monitoring layer (4) is disposed outside the gradient oxide layer (3); A partitioned gradient thickness wear-resistant surface layer (5) is disposed on the outside of the conductive monitoring layer (4).
2. The wear layer structure for a hard rock tunneling machine cutter head according to claim 1, characterized in that, The metal connection layer (2) is integrally formed from Fe-Cr-C iron-based alloy, and the metal connection layer (2) is connected to the cutter head steel substrate (1) and the conductive monitoring layer (4) by hot pressing.
3. The wear layer structure for a hard rock tunneling machine cutter head according to claim 1, characterized in that, The total thickness of the gradient oxide layer (3) and the metal bonding layer (2) is 200~500μm.
4. The wear layer structure for a hard rock tunneling machine cutter head according to claim 1, characterized in that, The conductive monitoring layer (4) has a thickness of 50~100μm and is integrally formed from titanium carbide ceramic.
5. The wear layer structure for a hard rock tunneling machine cutter head according to claim 1, characterized in that, The surface of the conductive monitoring layer (4) is also provided with a nickel foil electrode (42), the thickness of which is 5~10μm.
6. The wear-resistant layer structure for a cutterhead of a hard rock tunnel boring machine according to claim 1, characterized in that, The partitioned gradient thickness wear-resistant surface layer (5) includes: The edge area has a thickness of 15~20mm; The thickness of the area surrounding the tool is 10~15mm; The central area has a thickness of 5-8mm.
7. The wear layer structure for a hard rock tunneling machine cutter head according to claim 1, characterized in that, The outer surface of the partitioned gradient thickness wear-resistant surface layer (5) is also coated with an aluminum nitride coating (51), the thickness of which is 5~10μm.