71911 ACD/P4AQGB
71900 Series Super Precision Angular Contact Ball Bearings
Image may differ from product. See technical specification for details.
Basic Information
Main Dimensions
Ball & Washer Dimensions
Performance
Materials
- Fast delivery
- Enjoy discounts on bulk purchases
- Secure Payment
- Fast Global Shipping
Product Overview and Core Advantages
The 71911 ACD/P4AQGB is a high-precision angular contact ball bearing designed for demanding applications requiring exceptional rotational accuracy and rigidity. Engineered to a P4A tolerance class, this bearing excels in handling combined radial and axial loads simultaneously. Its universal matchable (SU) design allows for flexible mounting in various preload configurations, while the phenolic cage and factory-applied lubrication enable reliable high-speed performance up to 46,000 rpm. This bearing is an ideal solution for machine tool spindles and other high-precision machinery.
71911 ACD/P4AQGB Bearing Model Code Explained, Specifications & Naming Convention
| Code Segment | Technical Meaning |
|---|---|
| 71911 | Basic bearing series and size designation (55mm bore, 80mm OD) |
| AC | Angular Contact design with a 25° contact angle |
| D | High load capacity design with optimized internal geometry |
| P4A | High precision tolerance class with enhanced running accuracy |
| QGB | Special grouping code indicating universal matchable (SU) bearings supplied in sets of 4 |
Structural Features and Performance Benefits
Optimized Internal Geometry: The 25° contact angle and large ball diameter (7.938mm) with 23 balls provide superior load carrying capacity for both radial and axial forces.
High-Speed Capability: The phenolic cage offers excellent strength-to-weight ratio and smooth operation at limiting speeds of 46,000 rpm, while factory lubrication ensures immediate startup performance.
Precision Engineering: Manufactured to P4A tolerance class with tight dimensional control (bore and OD tolerance: -0.004mm to 0), ensuring minimal runout and vibration in precision applications.
Universal Matching Design: The SU designation allows bearings to be mounted in various preload configurations (back-to-back, face-to-face, or tandem) without selective matching, simplifying installation and maintenance.
71911 ACD/P4AQGB Bearing Typical Application Areas
- Machine Tool Spindles: High-precision machining centers, grinding spindles, and milling applications
- High-Speed Motors: Precision electric motors and spindle drives requiring minimal vibration
- Industrial Pumps: Centrifugal pumps and compressor systems handling combined loads
- Precision Instruments: Measuring equipment and optical devices demanding exceptional running accuracy
- Aerospace Components: Guidance systems and auxiliary power units requiring reliable high-speed operation
