Our co. is a specialized enterprise for hot rolling ball ground steel balls produced according to the standards of GB8649. The yearly capacity is 72,000 tons of all sorts of ball ground steel balls of 20mm-150mm.The material of ball ground steel balls is excellent quality special steel. Its technological characteristics are: (1) We have purchased from steel plant special round steel for corresponding steel balls. (2)Round steel is heated to 800-900. (3) Once ball formation by rolling machine of the production line. (4) With advanced finishing technique, abrasion loss of ball ground steel balls gets lower, its hardness becomes larger. (Hardness for ground balls whose diameters are more than 100mm can be kept from the surface to the center of the balls). It has high tenacity, the breakage rate is rather low. (but its life time is more than twice that for casting balls). These products are widely used in mines, mineral media, all sorts of grinding machines in bad environment. These products can be stably used for a long time, the effect is rather ideal. Its properties are as follows: 1. High hardness, high abrasion-proof, high whole hardness: its surface hardness is HRC56-60. its central hardness is HRC54-59HRC. The hardness difference is less than 5HRC. 2. High tenacity: the impact tenacity is more than 17J/cm2. Extremely low breakage rate: the properties for peel resistant and breakage resistant is more than 100 times those of other products. There are almost no breakages when ball impact times reach 100,000 to 200,000. Actual breakage rate is less than 0.01%. Specifications of products Nominal diameter Theoretical diameter Theor