CBN (Cubic Boron Nitride) cutting tools are highly effective in the wind power industry, particularly for machining bearings.
Bearings used in wind turbines endure harsh operating conditions, such as high loads, variable speeds, and exposure to challenging environments, which necessitates superior performance in both durability and precision.
Processing wind power industry bearings involves several key challenges:
1. High Hardness of Workpiece Material
The bearing materials used in wind power applications have high hardness, typically HRC58-62 after heat treatment. This places stringent demands on the wear resistance of cutting tools.
2. Large Part Size and Continuous High-Temperature Resistance
Bearings for wind power are usually large, with slewing ring bearings often exceeding 1 meter in diameter. Cutting tools need to withstand continuous high temperatures during machining.
3. Uneven Margin Due to Deformation After Heat Treatment
Parts tend to deform after heat treatment, causing uneven margins, especially on bearing raceways. This requires cutting tools that can handle intermittent cutting and resist impact.
4. High Machining Accuracy and Surface Roughness Requirements
Bearings need precise assembly, so dimensional and shape tolerances are critical. Typical tolerance ranges are 0.03-0.05mm, and surface roughness must reach Ra0.8 or better.
Case Studies
Case 1: Inner and Outer Ring Machining for Wind Power Bearings
- Workpiece Details:
- Type: Wind power bearing
- Material: 42CrMo4
- Machining Location: Bearing inner race and outer race
- Hardness: HRC60
- Diameter: Inner race D2165XSD600.32, outer race D2143XSD76.2
- Equipment: CNC Vertical Turning Lathe
- Surface Roughness: Ra0.8
- Insert & Code: Solid CBN Insert RNGN090300 S0102002
- Machining Parameters:
- Cutting speed (Vc): 150-180m/min
- Feed rate (f): 0.1-0.2mm/r
- Depth of cut (Ap): 0.1-0.8mm
Case 2: Finish Machining of Cylindrical Rollers for Wind Power Bearings
- Workpiece Details:
- Type: Cylindrical roller for wind power bearing
- Material: 100CrMnsxxx
- Hardness: HRC58-62
- Surface Roughness: Rz2-3
- Processing Method: Continuous cutting
- Cooling Method: External cooling
- Machining Details: Finish turning the cylindrical roller
- Insert & Code: PCBN Insert DNGA150612-4N S0102505
- Machining Parameters:
- Cutting speed (Vc): 200m/min
- Feed rate (f): 0.3mm/r
- Depth of cut (Ap): 0.12mm
Conclusion
In wind power bearing machining, the high hardness of materials, large component size, uneven margin after heat treatment, and strict requirements for machining accuracy and surface finish demand cutting tools with excellent wear resistance, high-temperature tolerance, and impact resistance.
The CBN and PCBN inserts used in these cases effectively meet these requirements, showcasing machining efficiency and product quality improvements through optimized cutting parameters and tool selection.
