Dongfeng
SFE Series Ground Ball Screw Assembly
SFE2005 ground ball screw assembly at C5 precision grade, delivering ±0.008 mm/300 mm lead accuracy with a 20 mm shaft and 5 mm lead — designed for semiconductor wafer handling, medical imaging stages, and precision CNC applications where positional repeatability under 0.01 mm is a hard requirement.
Highlights
- C5 precision grade per ISO 3408 — lead accuracy ±0.008 mm/300 mm, axial play below 0.005 mm with pre-loaded double nut
- 20 mm shaft diameter, 5 mm lead — ball track ground after heat treatment for consistent geometry along full travel length
- GCr15 chrome steel shaft, through-hardened and precision ground; nut body alloy steel with surface treatment for corrosion resistance
- Pre-loaded double-nut assembly supplied; pre-load class available upon request (light/medium) to match stiffness and drag torque requirements
- Suitable for vertical axis and high-duty-cycle applications — axial rigidity up to 280 N/µm under rated pre-load conditions
- Standard lengths 200 mm to 1200 mm; longer shafts and custom end machining per customer drawing available upon request
- Low thermal growth design: ground thread geometry minimizes friction heat at high feed rates, relevant for semiconductor and optical alignment stages
- Compatible with standard BK/BF 20 fixed bearing blocks and SFE2005 nut housings; metric flange pattern
| Precision Grade | C5 (ISO 3408) |
|---|---|
| Shaft Diameter | 20 mm |
| Lead | 5 mm |
| Lead Accuracy | ±0.008 mm / 300 mm |
| Axial Play | < 0.005 mm (pre-loaded double nut) |
| Material | Chrome Steel (GCr15 / 52100), ground |
| Dynamic Load Capacity | 12.7 kN (double nut) |
| Axial Rigidity | Up to 280 N/µm |
| Standard Lengths | 200 mm – 1200 mm |
| Reference SKU | SFE-2005-600 |
SFE Series — Ground Ball Screw
Where rolled screws reach their limit, the SFE2005 starts. The 20 mm shaft is ground after through-hardening — not before — so the ball track geometry reflects the final metallurgical state of the material. Result: C5 grade per ISO 3408, lead accuracy ±0.008 mm per 300 mm, axial play held below 0.005 mm with the pre-loaded double-nut assembly. These numbers matter on semiconductor wafer transfer stages, ophthalmology scanner axes, or any motion platform where a 0.01 mm drift shows up in product yield.
Specifications
| Parameter | Value |
|---|---|
| Precision Grade | C5 (ISO 3408) |
| Shaft Diameter | 20 mm |
| Lead | 5 mm |
| Lead Accuracy | ±0.008 mm / 300 mm |
| Axial Play | < 0.005 mm (pre-loaded double nut) |
| Material | GCr15 Chrome Steel, precision ground |
| Dynamic Load Capacity | 12.7 kN (double nut assembly) |
| Axial Rigidity | Up to 280 N/µm under rated pre-load |
| Standard Lengths | 200 mm – 1200 mm |
Key Features
Post-Hardening Grind
Ball track is ground after heat treatment, removing distortion introduced during hardening. This is what separates C5 ground from C7 rolled in sustained high-cycle duty.
Ground PrecisionPre-loaded Double Nut
Factory-set pre-load eliminates backlash for bidirectional positioning. Pre-load class (light or medium) can be specified at order to balance rigidity against drag torque for the application.
Zero BacklashLow Thermal Growth
Ground thread geometry produces lower friction heat at high feed rates versus rolled — relevant when thermal expansion of the screw shaft would otherwise accumulate as positioning error over long duty cycles.
High RigidityTarget Applications
Semiconductor wafer handling and inspection stages, medical imaging linear axes (CT, ophthalmology), precision machining centers (VMC/HMC feed axes), optical alignment platforms, and measurement equipment. For lighter-duty desktop CNC and engravers where C7 tolerance is acceptable, the SFU rolled series offers a more cost-efficient alternative.
FAQ
What MOQ applies to the SFE ground series?
MOQ is 10 pieces per configuration (diameter + lead + length combination). For mixed lengths or custom end machining, minimum order quantity and lead time are confirmed per inquiry — typically 20-35 business days for ground series versus 7-15 for standard rolled.
Is the pre-load class fixed, or can it be customized?
Pre-load class can be specified as light or medium at order. Light pre-load suits high-speed axes where drag torque must stay low; medium suits applications needing higher axial stiffness. Exact pre-load force values and corresponding drag torque data are available upon request.
Do you provide material certificates or inspection reports?
Material certificates (GCr15 heat number traceability) and dimensional inspection reports are available upon request for orders requiring documentation. Please specify at inquiry stage so we can factor inspection time into the lead time.
Request Specifications & Pricing
Provide shaft length, pre-load class, end machining requirements, and order quantity. We respond within 1 business day with pricing and lead time confirmation.
Request a Quote
