... four years by our technical department, using the sintering process with introducing advanced equipments from abroad. The property and technical specifications ... level in the worldSize: Φ0-0.063,Φ0.063-0.125,Φ0.125-0.25, Φ0.25-0.425,Φ0.4-0.6,Φ0.6-0.8,Φ0.8-1.0, Φ1.0-1.2,Φ1.2 ... don't have the appearance of being hollow, anomalistic, or with small beads on the surface. Excellent tenacity, this advantage ...