Return material. Sieve the powder mixed in step 7 through a vibrating powder sieve equipped with a 50-mesh screen, and then pour it into a double cone mixer for mixing.
Material return. Mix the powder in step 7 and pass it through a vibrating screen with a 50 mesh sieve, then pour it into a double cone mixer for mixing.
Return the material. Sieve that powder mix in step 7 with a vibrating sieve equipped with a 50-mesh screen, and then pouring into a biconical mixer for mixing.