| 摘要 |
The invention relates to a process and device for metal coating by flame spraying and cold-hardening by particle blasting, the process allowing to substitute steels of which the shaft-type long parts are manufactured by using steels of lower mechanical characteristics and cold-hardening the same only in the wear-prone regions, which leads to lowering the production costs by eliminating energy-consuming and polluting surface heat treatments. According to the invention, the process consists in that both the surface preparation of the part to be cold-hardened, the metal-coating powder application and the cold-hardening are carried out within a single installation by means of the same spraying/blasting device by adequately separating the supply circuits and by a more precise control of the process parameters. The device claimed by the invention is of a combined type, between a device for thermal spraying with powder into the combustion flame and a cold-hardening blasting device by the compressed-air blasting of the particles, with direct control of the process parameters, the compressed air entraining blasting/cold-hardening particles from the particle tank () which pass then through a central channel () projecting the particles onto the substrate surface, and by thermal spraying upon the metal coating operation, the compressed air generated by the compressor () entraining the powder from the tank () passing then through the central channel () of the spraying/blasting device () where it meets the flue gases passing through some channels (), the powder being melted and applied onto the substrate by spraying, while through other channels () there flows a compressed air stream for cooling the device. |
