The surface roughness of cast impeller refers to the micro geometric characteristics composed of micro spacing and peak valley on the surface of cast impeller. It is an important index to measure the surface quality of rough impeller castings.
For the surface roughness inspection of impeller casting, the standard comparison sample block is used to inspect according to the standard of surface roughness comparison sample block (casting surface) (GB / t6060.1-1997). The surface roughness of cast impeller is ra1 6. The rest is RA3 2 ~ 1.6. Because the upper and lower end faces have machining allowance, the surface roughness of the hub and rim end faces can fully reach RA3 2～1.6。 Meet the surface roughness requirements of impeller castings.