In the professional field of ball screws, "lead" refers to the distance the nut travels axially during one revolution of the screw.
For buyers, choosing between a large lead and a small lead essentially involves balancing speed with accuracy/thrust. Below is a comparison of the key differences between the two.
| Feature | High Lead Ball Screw | Low Lead Ball Screw |
| Movement Speed | Extremely fast. Suitable for high-frequency, rapid positioning scenarios. | Slower. Suitable for fine adjustments and slow feed. |
| Positioning Accuracy | Relatively low. A large lead means that the rotation angle is more sensitive to the effect of displacement. | Extremely high. Small pulse equivalent, resulting in more precise micro-displacement control. |
| Load Capacity | Lower. Under the same driving torque, the axial thrust generated is smaller. | It is relatively high. By utilizing the principle of helix angle in the thread, it can generate greater axial thrust. |
| Self-Locking | It is prone to reversible transmission. When used vertically, the load is prone to sliding down due to gravity. | Good. Although ball screws generally have poor self-locking properties, they are relatively more stable with a small lead. |
| Temperature Rise And Noise | High-speed operation easily generates heat and requires high dynamic balance. | It operates smoothly with relatively low noise and heat generation. |
Large Lead: The "Sprinter" for Efficiency
Large lead screws (such as 25mm in diameter, 25mm or larger lead) are primarily used in high-speed automated equipment.
Advantages: Achieves extremely high linear speeds even at relatively low motor speeds. This reduces motor heat generation and extends the lifespan of the drive system.
Challenges: Due to the large thread helix angle, it places higher demands on the motor's braking capability (brake). When installed vertically, a holding brake motor must be used; otherwise, the nut is highly susceptible to falling due to gravity after power failure.

Small Lead: The "Precision Needle" for Power
Small lead screws (such as 25mm in diameter, 4mm or 5mm lead) are the preferred choice for machine tools and precision measuring instruments.
Advantages: High mechanical magnification. For the same motor output torque, a smaller lead can translate into greater cutting or compressive force. Simultaneously, it offers higher resolution, achieving micron-level precision positioning.

Challenges: High-speed movement requires a significant increase in motor speed, which may trigger the lead screw's "critical speed," causing resonance or severe vibration.
3. Application Scenarios Recommendations
Situations requiring a large lead:
Woodworking machinery, laser cutting machines (requiring rapid idle return), handling robots.
Automated production lines requiring high cycle times.
Situations requiring a small lead:
CNC machining centers, CNC grinding machines (requiring heavy-duty cutting and high precision), laboratory precision displacement stages, injection molding machine injection mechanisms (requiring enormous thrust).