Ball quality is defined as follows:

Surface Hardness is measured on the Rockwell Scale. Minimum hardness is RC 60 for carbon, chrome and 440 stainless  balls and varies for other p

roducts according to the material and desired toughness.

Case Depth is the radial distance from the ball surface to the point where hardness falls to Rockwell C 50. The core is the remaining soft inner area.

Durability fatigue life tests are performed to assure long durability and maximum strength.
Surface Integrity is defined as the surface smoothness and freedom from defects such as flats, pits, soft spots and cuts. Balls must be free of such defects when inspected without magnification.
Size is the mean diameter, measured between two parallel planes on the ball surface.
Sphericity is defined as the deviation from a true spherical form (out-of-round condition).

Gosen focuses on delivering the best quality accessories solutions is what sets us apart. Although the ball is small, we believe each ball has its importance to customers’ every applications. Gosen always commits itself to ensure each ball we provide you is quality. Every Gosen ball is manufactured to American Bearing Manufacturers Association (ABMA) Standard No.10 and to customer specifications where appropriate. Strict lot control throughout production ensures traceability of both the wire used and the experienced personnel involved at each stage of manufacturing to delivery. Each division maintains a highly developed system of process control that assures consistency at each step. Testing methods are in place to achieve superior quality on any grade product. The quality and after service is 100% guaranteed.