I recent years, multi-line mill - line grinding um - corrosion wear ums, um aasive wear, wear ums, sewage um wear, wear-resistant um sewage, solid waste treatment wear ums, charcoal um wear black, titanium dioxide wear ums, high shear mixing and grinding um - ieline colloid mill and other roducts, has won 42 national atents of indeendent intellectual roerty rights certificates ...