Comparison and Analysis of Rolled Ball Screws and Ground Ball Screws

I. Core Difference (One-Sentence Summary)

Rolled Ball Screw (Cold Roll Forming) = Low Cost, High Efficiency, General Precision; Ground Ball Screw (Precision Grinding) = Ultra-High Precision, High Rigidity, Long Service Life, Suitable for Precision Equipment.

II. Detailed Parameter Comparison Table

III. In-Depth Analysis of Key Differences

3.1 Root Cause of Precision and Performance Gaps

• Rolled: Affected by die wear and metal spring back, the raceway has large shape errors, making it difficult to achieve high preload, and slight gaps are likely to occur at high speed/commutation.

• Ground: The grinding machine can correct heat treatment deformation, and the raceway has extremely high profile accuracy and position accuracy, enabling zero-backlash transmission.

3.2 Material and Process (Suitable for 95Cr18/102Cr17Mo)

• Rolled: Mostly uses medium and low carbon steel, with a cold work hardened surface and a soft core, making slender parts prone to deformation.

• Ground: Commonly uses high carbon chromium stainless steel (95Cr18, 102Cr17Mo), with overall deep hardening and extremely strong dimensional stability.

3.3 Difficulty in Controlling Length/Diameter Tolerance

• Rolled: The longer the length, the worse the rolling deformation and straightness, and the length tolerance is much more difficult to guarantee than the diameter tolerance.

• Ground: It can be controlled through multiple grinding, straightening and aging processes, and both length and diameter accuracy are easy to guarantee.

IV. Typical Application Scenarios

4.1 Rolled Ball Screws (Cost-Effectiveness Priority)

• Ordinary manipulators, packaging machines, injection molding machines, lifting platforms

• General automation, non-standard equipment, low-precision transmission scenarios

4.2 Ground Ball Screws (High Precision Priority)

• CNC machine tools, precision grinders, medical equipment (IVD automated assembly lines, surgical robots)

• Semiconductor equipment, measuring instruments, robots, aerospace equipment

• Precision lead screws, high-precision transmission scenarios related to life sciences

V. Selection Suggestions (Direct Application)

• Choose Rolled: Precision requirement of C7 and below, limited budget, large batch, general automation scenarios.

• Choose Ground: Precision of C5 and above, zero backlash requirement, high-speed/heavy-load working conditions, high-precision equipment such as medical/semiconductor/machine tools, and long-term precision stability required.