A high chromium, quality index:

The chromium content is more than 10%, the carbon content in 1.80%-3.20% between called high chrome grinding ball, the national standard requirements of high chromium ball hardness (HRC) must be greater than or equal to 58 or more AK than 3.0J/ cm, shock value 2, if the hardness of high chromium high temperature quenching + tempering treatment must be used (there are oil quenching and air quenching two quenching method in domestic high chromium quenching), such as the measurement of hardness (HRC) below 54 shows high chromium ball without quenching.

In two, chromium ball quality index:

The chromium content of 3% ~ 7%, the carbon content in 1.80%-3.20% between called chrome balls, impact value AK is greater than or equal to 2.0J/ cm 2, national standard requirement in chromium ball hardness (HRC) must be greater than or equal to 47 or more, in order to ensure the quality of chrome steel ball in high temperature tempering (to eliminate casting stress goals), such as the steel ball surface dark red indicates that the product has been the high temperature tempering treatment, such as the steel ball surface is still a metal color indicates that the products are not high temperature tempering.

Three, low chromium ball quality index:

The chromium content of 0.5% ~ 2.5%, the carbon content are called low chromium ball in between 1.80%-3.20%, the national standard of low chromium ball hardness (HRC) must be greater than or equal to 45 or more AK than 1.5J/ cm, impact value of 2, in order to ensure the quality of steel ball low chromium ball is also high temperature tempering (to eliminate casting stress purposes), such as the steel ball surface dark red indicates that the product has been the high temperature tempering treatment, such as the steel ball surface is still a metal color indicates that the products are not high temperature tempering.

Four, forged ball quality index:

By the steel with different process into the ball, the carbon content below 1%, the material is crucial to the quality of the product (alloy elements), no casting surface of mouth, ball will not appear in the grinding process of deformation, always is spherical, the production technology at present are:

(1) the air hammer forging: more common, but the human cost is high, and the product quality is affected by artificial factors, the quality of instability;

(2) roll section: this process only Shandong Huamin steel ball Limited by Share Ltd in use, as the independent research and development and manufacturing, is the domestic first fully automated forging production line, low labor cost and stable product quality, a line of annual production capacity of at least 30000 tons.

Hardness (HRC) and the wear resistance of the steel material and process according to different and somewhat difference, Huamin steel ball surface hardness can reach above 60, both inside and outside the hardness difference of 1-3 degree, grinding ball is superior to the overall wear high chromium.

Comparison of five, wear resistance:

(1) gene in different: forging ball material for high quality steel, and cast ball material scrap;

(2) cast ball surface a casting opening, trachoma and zoning, and forging ball surface smooth, the surface quality seriously affects the deformation of the ball in the grinding process, forging ball due to surface quality is better than that of cast ball, not easy to deformation in the process of use.

(3) forging ball impact toughness is greater than 12, and the cast ball is only 3-6, the decision breaking rate forging ball is better than that of cast ball.

(4) the mill ball casting for diameter of 1.5-3.8m, and is suitable for forging ball mill diameter 1.5-11m and above.

(5) is only applicable to dry grinding ball casting and forging ball, because of its good gene - quality steel, born with corrosion resistance, dry grinding and wet grinding are applicable.