71811 ACD/P4DBB
71800 Series Super Precision Angular Contact Ball Bearings
Image may differ from product. See technical specification for details.
Part No.
Part No.
71811 ACD/P4DBB
Basic Information
System of measurement
Metric
Weight
0.16 kg
Tolerance class
P4
Seal type
Open
For load direction
Angular Contact
Main Dimensions
Bore diameter
55 mm
Bore diameter tolerance
-0.004mm to 0
Outside diameter
72 mm
Outside diameter tolerance
-0.004mm to 0
Width
18 mm
Width tolerance
-0.2mm to 0
Contact angle
25 °
Ball & Washer Dimensions
Ball diameter
4.762 mm
Ball quantity
29
Performance
Temperature range
- 30°C to 110 °C
Radial dynamic load rating
3510 lbf
Radial static load rating
4590 lbf
Limiting speed
34 X 1000 rpm
Lubrication
Lubricated
Matched arrangement
Duplex Back-to-Back (DB)
Number of bearings in matched set
2
Universal matching bearing
No (Standard)
Preload
Light / Class B
Materials
Ring material
Chrome Steel
Ball material
Chrome Steel
Cage material
Phenolic
Technical Drawings
No drawings available at the moment, will be launched soon
In Stock
Price available upon request.
Our sales team will respond within 24 hours with a competitive quote tailored to your requirements.
REQUEST A QUOTE
- Fast delivery
- Enjoy discounts on bulk purchases
- Secure Payment
- Fast Global Shipping
71811 ACD/P4DBB Bearing Product Overview & Core Advantages
The 71811 ACD/P4DBB is a super-precision angular contact ball bearing designed for the most demanding applications. This duplex back-to-back (DB) matched pair is preloaded to Light / Class B standards, delivering exceptional system rigidity and rotational accuracy. Its primary advantage lies in its ability to handle combined loads—significant radial and thrust loads from both directions—simultaneously, making it an ideal choice for high-speed spindles and precision machinery requiring uncompromising performance and dimensional stability.
71811 ACD/P4DBB Bearing Model Code Explained, Specifications & Naming Convention
| Suffix Code | Technical Meaning |
|---|---|
| ACD | Indicates a 25° contact angle and a specific internal design optimized for high rigidity and speed. |
| P4 | Denotes an ultra-high precision tolerance class (ABEC 7 / ISO P4), ensuring minimal runout and superior running accuracy. |
| DB | Specifies the bearing set is supplied as a Duplex Back-to-Back matched pair, preloaded for maximum stiffness. |
71811 ACD/P4DBB Bearing Structural Features & Performance Benefits
- High Rigidity & Running Accuracy: The back-to-back duplex arrangement and P4 precision class create an exceptionally stiff bearing system that minimizes deflection under load, crucial for maintaining precision in machining and positioning.
- Superior Load Capacity: The 25° contact angle is engineered to efficiently support substantial combined radial and axial loads from both directions, a key feature of angular contact bearings.
- Optimized High-Speed Performance: The lightweight phenolic resin cage reduces centrifugal forces, while the open design and pre-lubrication facilitate efficient cooling, enabling operation at a high limiting speed of 34,000 rpm.
- Premium Material & Construction: Manufactured from high-grade chrome steel for rings and balls, this bearing ensures long-term durability and consistent performance under the specified temperature range.
71811 ACD/P4DBB Bearing Typical Application Areas
This precision bearing is engineered for high-performance applications, including:
- Machine Tool Spindles: High-speed machining centers, grinding spindles, and CNC lathes.
- Precision Drives & Feed Systems: High-accuracy robotic arms, linear actuators, and indexing tables.
- High-Frequency Motors & Spindles: Where minimal runout and high rigidity are paramount.
- Medical & Laboratory Equipment: Centrifuges and other precision instruments requiring smooth, accurate rotation.
