Application Of Laser Cladding Technology: Repairing The Cutting Pick Of Coal Cutter

Cutting pick is one of the vulnerable parts in mining and roadway driving machinery, which is the main tool for coal dropping and crushing. Its performance directly affects the production capacity of the shearer, power consumption, working stability and other related parts of the service life. There are many kinds of picks, and the general structure is to embed the carbide cutter head in the quenched and tempered low-alloy steel cutter body.

The cutting pick is subjected to high cyclic compressive stress, shear stress and impact load during operation. This may lead to the tool head falling off, the tool break and the tool head, tool body wear. Because the mechanical properties of the cutter body directly affect the service life of the cutter, the reasonable selection of the material of the cutter body and the effective heat treatment method have positive significance to reduce the wear and break of the cutter body, and the consumption of the cutter, improve the operation rate of the mining machinery, and increase the comprehensive economic benefits of coal mining production.

The cutting pick is a vulnerable part of mining machinery. Through long-term analysis and research of the cutting picks, the reliability of the cutting picks is simply analyzed from several aspects, such as the selection of new picks, the layout of the picks and the improvement of the pick's structure, so as to improve the reliability of the cutting picks, reduce the proportion of the tooth consumption in the cost of tons of coal, and improve the effective working time of the coal cutter. The reliability of the cutting pick is related to many factors, such as the pick itself, the shearer's factor and the occurrence condition of the coal seam.

The staff who often operate the coal cutter must know very well that the shearer cutter is one of the more easily damaged equipment, and the problem of repairing the cutter after damage has become the most concerned problem of manufacturers and customers. Today, we introduce a method of repairing the cutter, so that the product can achieve the greatest economic value.

Ultra-high Speed Laser Cladding, also known as Extreme High-Speed Laser Cladding (EHLA), invented by Fraunhofer ILT of Germany, is praised as the most competitive process that can replace electroplating technology at present. In 2017, he was awarded the Joseph von Fraunhofer Innovation Award, the German Laser Innovation Award (Berthold Leibinger Innovationspreis) and the Steel Innovation Prize of the German Steel Association program) and other awards due to the innovative technological progress it brings to the industry.

The ultra-high speed laser cladding technology is mainly used to improve the wear resistance, corrosion resistance, high-temperature resistance, and oxidation resistance of the surface of the parts, so as to achieve the goal of surface modification or repair and meet the requirements of the specific properties of the material surface.

The ultra-high speed laser cladding technology essentially changes the melting position of the powder, so that the powder will melt at the intersection of the laser above the workpiece, and then evenly coated on the surface of the workpiece. Its cladding rate can be as high as 20-200m/min, due to the small heat input, heat-sensitive materials, thin walls and small-size components can be used for surface cladding and can be used in all new material combinations, such as aluminum-based materials, titanium materials or cast iron coating preparation. Since the surface quality of the coating is significantly higher than that of ordinary laser cladding, only simple grinding or polishing can be applied, so the material waste and subsequent processing amount are greatly reduced, and the ultra-high speed laser cladding has irreplaceable application advantages in cost, efficiency, and thermal impact on the parts.