Wind power parts of special repair methods of laser cladding

Wind power 2019 - parts of special repair methods of laser cladding 06 - 28 kai senior engineer ( Nanjing AnWeiShi transmission technology co. , LTD. ) Laser cladding ( 激光熔覆) Is a surface modification technique, also called laser cladding and laser deposition. It refers to the different ways to add material in the cladding substrate surface coating materials selected by the laser irradiation to a thin layer of melted at the same time, the sum of the substrate surface and rapid solidification formed dilution rate is extremely low, metallurgical combination of surface coating and matrix, and significantly improve the primary surface wear-resisting, corrosion resistance, heat resistance, oxidation resistance and electrical properties of process method, so as to achieve the aim of surface modification or repair, both meet the requirements of the specific performance on the surface of a material, and save a lot of valuable elements. Laser cladding low dilution rate, compact structure, good coating combined with matrix, use and reliable. At present the application of laser cladding, its main use in three aspects: one is the material surface modification, such as turbine blade, roll, etc. ; Second, repair parts, such as wind power main shaft, planet carrier, planetary wheel, etc. ; Third, rapid prototyping, it is using metal powder sintering overlay, step by step a rapid manufacturing model. Our company is mainly used in wind power on the repair parts, figure 1 for using the method of laser cladding repairing planetary shaft neck. Figure 1 laser cladding method to repair the planet carrier shaft neck wind power components such as main shaft, bogie often found in the process of repair hair or wear serious, if not for repair cannot continue to use, before using the laser cladding method to repair, most parts according to scrap processing. At the end of 2014, our company for the first time by the method of laser cladding, the planet wheel inner hole to run the repair and heaven, has been nearly four years, in addition, the main shaft, the planet carrier ( Ductile iron) And high-speed shaft were developed using the technology to repair, and heaven already use more than two years, no one so problems. We adopt the special repair technology, greatly improve the utilization rate of the secondary parts, reduce the maintenance cost, and shorten the maintenance cycle gear box. Laser cladding process is simple and reliable method to repair parts, parts repair process is as follows: 1, to remove fatigue layer of parts repair location, generally require partial grinding or turning, the process of parts surface roughness has no special requirements. 2, according to the parts material characteristics preheating treatment, prevent defects such as cracks. 3, after preheating of the laser cladding parts, can generally be cladding 3 ~ 4 mm, if the fix position to demand higher hardness, thickness of cladding might reduce relatively, because the cladding layer thickness, hardness is higher and higher, in the case of without heat treatment, large area cladding prone to defects such as cracks. After cladding parts as shown in figure 2. Figure 2 after laser cladding of planet carrier journal 4, cladding to stress after annealing and penetrant inspection, ensure that after laser cladding parts without defect. 5, to machining of cladding layer, meet the requirements of drawing size. Journal of laser cladding parts machining, as shown in figure 3. Figure 3 planet carrier shaft neck after machining