The larger the steel ball is, the harder to get the precision grade. Ø 76.2 mm (3″) is the biggest apply diameter of steel ball batch manufacture machine. In the steel ball industry, big steel balls have low precision grade. Even the normal precision grade of Ø 76.2 mm chrome steel ball for wind turbine bearing is G 60 only.

Recently, Luoyang Mingzhen Bearing Steel Ball Co., Ltd. (MZ STEEL BALL) made batch trial production of Ø 76.2 mm big size high precision chrome steel balls and successfully extend the highest precision grade of our Ø 76.2 mm large size chrome steel ball to G 28. The specifications include variation of ball diameter, deviation from spherical form, surface roughness, hardness and so on totally satisfy the requirements of ISO3290-1:2008, GB/T 308.1-2013, ANSI/ABMA Std. 10A, DIN5401, JIS B 1501, ГООТ 3722, KS B 2001 and other international steel ball standards.