71909 ACD/P4ADBCGMM
71900 Series Super Precision Angular Contact Ball Bearings
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Part No.
Part No.
71909 ACD/P4ADBCGMM
Basic Information
System of measurement
Metric
Weight
0.26 kg
Tolerance class
P4A
Seal type
Open
For load direction
Angular Contact
Main Dimensions
Bore diameter
45 mm
Bore diameter tolerance
-0.004mm to 0
Outside diameter
68 mm
Outside diameter tolerance
-0.004mm to 0
Width
24 mm
Width tolerance
-0.2mm to 0
Contact angle
25 °
Ball & Washer Dimensions
Ball diameter
6.35 mm
Ball quantity
23
Performance
Temperature range
- 30°C to 110 °C
Radial dynamic load rating
4478 lbf
Radial static load rating
4050 lbf
Limiting speed
41 X 1000 rpm
Lubrication
Grease
Matched arrangement
Duplex Back-to-Back (DB)
Number of bearings in matched set
2
Universal matching bearing
No (Standard)
Preload
Moderate / Class C
Materials
Ring material
Chrome Steel
Ball material
Chrome Steel
Cage material
Phenolic
Technical Drawings
No drawings available at the moment, will be launched soon
Price:
$ 168.81
/ each
In Stock
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71909 ACD/P4ADBCGMM Bearing Product Overview & Core Advantages
The 71909 ACD/P4ADBCGMM is a precision duplex pair of angular contact ball bearings, pre-configured in a back-to-back (DB) arrangement. This matched set is engineered to deliver exceptional high rigidity and stability, making it ideal for applications requiring superior running accuracy. Its primary characteristic is the ability to support combined loads—significant radial loads and axial loads in both directions—simultaneously. Manufactured to a P4A tolerance class and preloaded to a moderate (Class C) level, this bearing assembly offers reliable, high-performance operation in demanding, high-speed environments.
71909 ACD/P4ADBCGMM Bearing Model Code Explained, Specifications & Naming Convention
| Code Segment | Technical Meaning |
|---|---|
| 71909 | Basic bearing series and size designation. |
| AC | Angular Contact design with a 25° contact angle. |
| D | Duplex pair (two bearings as a set). |
| P4A | High precision tolerance class, exceeding ABEC 7/ISO P4 standards. |
| DB | Matched arrangement: Back-to-Back. |
| CG | Moderate preload (Class C). |
| MM | The universal matching code for this specific preload and tolerance combination. |
71909 ACD/P4ADBCGMM Bearing Structural Features & Performance Benefits
- High Rigidity & Stability: The duplex back-to-back (DB) arrangement creates a wide, rigid support system that effectively resists overturning moments, ensuring exceptional shaft positioning accuracy and operational stability.
- Superior Load Capacity: The angular contact design with a 25° contact angle is optimized to handle combined radial and axial loads from both directions simultaneously.
- High-Speed Performance: The lightweight and robust phenolic cage minimizes centrifugal forces, reduces friction, and contributes to the high limiting speed of 41,000 rpm. The open design facilitates efficient lubrication management.
- Precision & Accuracy: Manufactured to P4A tolerance class with strict dimensional control on the bore diameter, outside diameter, and width, this bearing guarantees smooth, quiet, and precise rotation essential for high-end machinery.
- Durable Construction: Components made from chrome steel provide excellent hardness, wear resistance, and a long service life under demanding operating conditions.
71909 ACD/P4ADBCGMM Bearing Typical Application Areas
This precision bearing set is ideally suited for applications where high speed, rigidity, and accuracy are paramount. Key industries and equipment include:
- Machine Tool Spindles: For high-speed milling, grinding, and turning centers.
- Precision Spindles: Used in PCB drilling, engraving machines, and other high-precision automated equipment.
- High-Frequency Motors: Supporting spindles in applications requiring rapid acceleration and deceleration.
- Medical Equipment: Critical components in high-speed dental handpieces and laboratory centrifuges.
- Robotics: Providing accurate and rigid rotation in robotic arm joints and precision actuators.
