Cutting picks play a crucial role in mining machinery like shearers and tunnel boring machines, directly influencing the effectiveness and safety of mining operations. As mines delve deeper and encounter increasingly intricate conditions, the demands for cutting pick performance escalate accordingly. Therefore, studying ways to improve the performance of cutting picks is of great significance for improving the overall performance of mining machinery and promoting efficient and safe mining of mines.
Material
Material selection for cutting picks is crucial to improving their performance. Because the working environment of the cutting pick is unique, its failure symptoms include loss of the cutting pick, fragmentation of the cutter head, carbide wear, etc. These symptoms are all related to the material. Therefore, the material selection of the cutting pick needs to meet some strength and hardness requirements. The strength is mainly bending strength and tensile strength, and it also needs to meet high impact toughness. In addition, the selection of materials should be based on the specific use environment and conditions.
Structural design
Reasonable structural design can reduce the stress concentration of the cutting pick, improve its impact resistance, and affect its wear resistance and service life. Effective design methods are crucial for ensuring that the geometry, size, and geometric parameters of the cutting picks, the arrangement of the cutting picks, and the corresponding cutting parameters are all optimized. It guarantees uniform forces during operation, consistent wear levels, and a seamless movement process. Ultimately, this enhances work efficiency, ensuring reliability improvements.
Overlay welding of wear-resistant layer
Addressing the challenge of rapid wear and failure in cutting picks involves employing a surfacing welding method. This method entails adding a surface layer in the form of an annular belt, approximately 20-30mm wide and 2-3mm thick, along the circumferential direction on the tooth body just below the apex of the cutting pick cone. This annular belt is the wear-resistant cladding layer. Widely utilized wear-resistant cladding materials include martensite cladding alloy, the high-chromium Fe-Cr-C alloy system, tungsten carbide, niobium carbide, and similar options. The function of the pick wear-resistant surfacing layer is to compensate for or change the performance degradation caused by the carbide tip brazing process when forming the tooth body circumference. The other is to further optimize or enhance the performance of the cutter head. Of course, the latter’s significance becomes more pronounced when employing a tooth manufacturing process that involves initial brazing of the cutter head followed by overall heat treatment. But the actual situation is not simple. The appearance and use of cut-off wear-resistant cladding convert or partially convert the friction and impact between the cut-off cutter head and the cut coal rock into the friction and impact between the cladding and the cut coal rock. Friction wear and impact damage between them are influenced not only by the characteristics and compatibility of the two contact materials but are also subject to numerous factors in the coal mining process.
Brazing and heat treatment processes
Brazing and heat treatment processes of cutting picks are pivotal technologies for ensuring their quality and service life. A well-designed brazing process is essential for ensuring the strength and stability of the connections in cutting picks. At the same time, implementing stringent control over the brazing process ensures that the connection quality of each tooth meets the specified requirements, thus guaranteeing the smooth operation of the entire coal mining machine, tunnel boring machine, and other associated equipment. By controlling a well-designed heat treatment process, it is possible to alter the internal structure of the pick material, thereby enhancing its mechanical properties and wear resistance. At the same time, heat treatment can also eliminate internal stress in the material and improve its impact resistance. Therefore, it is necessary to select an appropriate heat treatment process based on the material and usage requirements of cutting pick.
Quality inspection and control
Establish a complete quality inspection system to strictly control the material, processing, and finished product quality of cutting picks to ensure the stability and consistency of product quality. By utilizing non-destructive testing, mechanical property testing, and other methods, potential quality issues can be identified and promptly addressed.
Enhancing the performance of cutting picks remains a central focus of attention and ongoing research in mining machinery. Through various ways, we can continuously improve the performance and quality level of cutting picks to meet the needs of efficient and safe mining in mines. As science and technology continually advance, and the ethos of innovation-driven development becomes ingrained in our collective mindset, there is every reason to believe that the future will bring forth a slew of high-performance cutting picks, making significant contributions to the mining industry.
