Product Overview
Yubao Transmission Technology produces precision shafts using premium alloy steel, processed through CNC centerless grinding or cylindrical grinding. Surface roughness achieves Ra≤0.4μm (precision grade), straightness ≤0.01mm/300mm, and diameter tolerance controlled to h6 grade. With over two decades of technical expertise, our products have supplied international high-end customers for more than ten years, with annual shipments exceeding one million pieces, demonstrating stable and reliable quality.
Technical Parameters
Basic Parameters
| Parameter | Symbol | Unit | Value/Range | Tolerance | Notes |
|---|
| Outer Diameter | D | mm | 21–350 | h6–h9 | Full range φ21–350mm |
| Total Length | L | mm | ≤1500 | ±0.05 | Max. machining length 1300–1500mm |
| Length-to-Diameter Ratio | L/D | — | ≤60:1 | — | Swiss-type lathe processing up to 1200/200 |
| Straightness | — | mm | 0.01 | ≤ | Per 300mm length |
| Cylindricity | — | mm | 0.005 | ≤ | Precision grinding guaranteed |
| Radial Runout | TIR | mm | 0.008 | ≤ | Measured between centers |
Surface Quality & Materials
| Parameter | Symbol | Unit | Value/Range | Tolerance | Notes |
|---|
| Surface Roughness | Ra | μm | 0.2–0.8 | ≤ | Precision grade ≤0.4, standard grade ≤0.8 |
| Surface Hardness | HRC/HV | — | 55–62 | — | Post-heat treatment hardness |
| Material Grade | — | — | Customized | — | Common: 40Cr, 20CrMnTi, GCr15, 16MnCr5 |
| Heat Treatment | — | — | Customized | — | Tempering/Carburizing/Nitriding/Induction |
| Center Hole Spec | — | — | 1.0–12.5 | — | Type A/B/C |
Machining Capabilities
| Process | Equipment | Range | Accuracy Achieved |
|---|
| Precision Turning | HEADMAN/DOOSAN/STAR CNC Lathes | φ21–350mm | Diameter tolerance ±0.003mm |
| Centerless Grinding | HFC-18/MFG20 | Below φ50mm | Roundness ≤0.001mm, Ra≤0.2μm |
| Cylindrical Grinding | MB1320E/DW-350-CNC | Length ≤1500mm | Radial runout ≤0.003mm |
| Heat Treatment | HF Induction/Continuous Furnace | Hardened layer 0.5–3mm | Surface HRC 58–62 |
| Inspection | VICI Vision/Mahr Roundness Tester | Full automatic inspection | 100% geometric tolerance verification |
Product Features
- Exceptional Surface Quality: CNC centerless grinding achieves Ra as low as 0.2μm, meeting high-speed rotation and precision fit requirements
- Strict Geometric Tolerances: Straightness ≤0.01mm, cylindricity ≤0.005mm, ensuring smooth operation with minimal vibration
- Flexible Material Selection: Available in bearing steel, alloy structural steel, stainless steel, and other materials for different operating environments
- Complete Heat Treatment: In-house HF induction hardening equipment and partnered heat treatment lines ensure controllable hardness gradient and case depth
- High-Volume Consistency: Automated production lines with robotic loading/unloading, SPC process control, CPK≥1.33, ensuring stable quality at million-piece scale
Typical Applications
| Application Sector | Specific Use | Technical Requirements |
|---|
| Household Appliances | Washing machine motor shaft, AC compressor shaft | Ra≤0.4μm, lifespan ≥10 years, low noise |
| Industrial Automation | Servo motor shaft, robot joint shaft | Straightness ≤0.01mm, high rigidity |
| Power Tools | High-speed output shaft | Balance grade ≤G6.3, long lifespan |
| Automotive | Steering sensor shaft, window regulator shaft | Compliant with IATF 16949 quality standards |
