Core Methods of Laser Cladding Technology in Repairing Agricultural Machinery

This method is mainly applicable to agricultural machinery components that suffer dimensional wear due to long-term friction, such as tractor power take-off shafts, harvester drum shafts, plowshare cutting edges, and seeder furrow openers. The repair process is clear and controllable: first, preprocess the surface of the worn component to remove oil stains, rust, and fatigue layers, ensuring the repair surface is clean and flat; then select matching cladding materials (commonly used wear-resistant materials such as WC-Co cemented carbide and NiCrBSi nickel-based alloy) according to the component's material (e.g., 45# steel, alloy steel) and working conditions; precisely deposit the materials on the worn parts using Laser Cladding equipment, controlling parameters such as laser power and powder feeding speed to form a strong metallurgical bond between the cladding layer and the substrate, achieving precise dimensional recovery; finally, perform finish machining on the clad component to ensure its dimensional accuracy meets the assembly requirements. For example, for tractor shaft parts with a wear amount of 0.5-5mm, the dimensional tolerance of the shaft diameter can be controlled within ±0.02mm after repair using this method, fully meeting the subsequent assembly needs.

For crack defects in agricultural machinery components such as casings, gears, and hydraulic component housings caused by heavy loads and vibrations, laser cladding crack repair method can achieve precise repair. Different from traditional welding repair which is prone to thermal deformation and crack propagation, this method has the advantages of low heat input and narrow heat-affected zone. The specific steps are: first, conduct flaw detection on the cracks to determine the length, depth, and direction of the cracks; open precise V-shaped or U-shaped grooves along the crack direction to facilitate the filling of cladding materials; select cladding materials matching the substrate material (e.g., low-carbon alloy cladding powder for structural steel components); precisely scan along the grooves with laser beams to fuse the cladding materials with the substrate and fill the crack defects; perform secondary flaw detection after repair to ensure the cracks are completely healed without internal defects. For example, after repairing cracks in the gearbox housing of a combine harvester using Laser Cladding technology, the mechanical properties of the housing can be restored to more than 90% of those of new products, effectively avoiding the seal failure problem caused by housing deformation after traditional welding repair.

This method is applicable to agricultural machinery components that have not yet completely failed but have shown early signs of wear and corrosion, such as seeder fertilizer tubes, irrigation equipment joints that are in long-term contact with soil and chemical fertilizers, and gear tooth surfaces subject to high-frequency vibrations. The core purpose is to prepare a high-performance coating on the component surface through Laser Cladding to pre-strengthen the component performance and extend its service life. The repair process does not require waiting for the component to completely fail and can be completed during regular maintenance: after simple pretreatment of the component surface, select corrosion-resistant and wear-resistant cladding materials, and prepare a 0.3-2mm thick coating on the component surface through laser cladding; no subsequent extensive finish machining is required, and it can directly meet the service requirements. For example, after NiCrBSi nickel-based alloy cladding strengthening on the inner wall of the seeder fertilizer tube, its corrosion resistance is improved by 3-5 times, which can effectively resist the erosion of chemical fertilizer media and extend the service life of the component by more than 2 times.

Under the background of the large-scale and precision development of modern agriculture, Laser Cladding technology can not only significantly reduce the operation and maintenance costs of agricultural machinery for farmers and farms, improve agricultural production efficiency, but also promote the transformation of the agricultural machinery maintenance industry towards high quality and greenization.