Ball Screw Precision Grades: C3 / C5 / C7 Explained

Precision grade is the most important specification when purchasing ball screws. Accuracy classes C3, C5 and C7 are commonly used in industrial applications. The number represents the tolerance level: the smaller the number, the higher the positioning accuracy.

Ball screw precision grade comparison diagram

C3 grade ball screw

C3 is ultra-precision grade, made by grinding process. It features very small travel deviation. C3 ball screws are widely adopted for high-end CNC equipment, precision laser machines and precision measuring devices, where repeated positioning accuracy is critical.

C5 grade ball screw

C5 is the most popular grade for general high-precision automation. It balances accuracy and cost. Our C5 rolled ball screws are a cost-saving choice for most automated production lines, material handling machines and standard CNC devices.

C7 grade ball screw

C7 is the economical grade. It is suitable for low-speed, low-precision applications such as simple conveying equipment, lifting mechanisms and simple automation frames.

How to choose?

You need to confirm your machine’s positioning tolerance requirement. If you have strict positioning demand, choose C3 ground ball screws. For standard automation machines, C5 rolled ball screws will be enough to save your budget.

We manufacture C3 ground ball screws and C5 rolled ball screws with custom specifications. Send your drawing to us for a customized quotation.