728 AC
Miniature Angular Contact Ball Bearings
Image may differ from product. See technical specification for details.
Basic Information
Main Dimensions
Performance
Materials
- Fast delivery
- Enjoy discounts on bulk purchases
- Secure Payment
- Fast Global Shipping
728 AC Bearing Product Overview & Core Advantages
The 728 AC is a high-performance double row angular contact ball bearing engineered for applications requiring exceptional precision and reliability. This precision bearing is designed to accommodate combined loads—simultaneous radial and bidirectional axial loads—with high efficiency. Its compact design, featuring a 8 mm bore and 24 mm outside diameter, makes it ideal for space-constrained, high-speed applications. Available in both sealed and open configurations, and with options for steel or ceramic balls, it offers versatility for demanding operational environments, delivering high rigidity and outstanding rotational accuracy.
728 AC Bearing Model Code Explained, Specifications & Naming Convention
| Code Segment | Technical Meaning |
|---|---|
| 728 | Basic bearing series designation, indicating a double row angular contact design with specific bearing dimensions (8mm bore, 24mm OD, 8mm width). |
| AC | Angular Contact, signifying the 25° contact angle optimized for handling significant axial loads. |
| Sealed / Open | Indicates availability with integral seals for contamination protection or an open design for direct lubrication systems. |
| P5 / P4 | ABEC precision class (P5/ABEC-5 or P4/ABEC-25), defining the level of running accuracy and vibration control. |
728 AC Bearing Structural Features & Performance Benefits
High Rigidity & Load Capacity: The double row ball complement and optimized raceway geometry provide superior high rigidity, enabling stable support for shafts under complex combined loads. The 25° contact angle is specifically chosen for efficient bidirectional axial load carrying.
High-Speed Performance: With options for lightweight phenolic or nylon cages, the 728 AC is engineered for high-speed operation, achieving remarkable limiting speeds of up to 90,000 r/min with oil lubrication. The availability of ceramic balls further enhances high-speed capability by reducing centrifugal forces.
Precision & Versatility: Manufactured to ABEC P5/P4 tolerance classes, this bearing ensures minimal runout and smooth operation. Its Universal Matchable (SU) designation allows for simplified mounting in preloaded arrangements, eliminating the need for selective assembly and reducing installation time and cost.
728 AC Bearing Typical Application Areas
The 728 AC double row angular contact ball bearing is ideally suited for high-demand applications, including:
- High-Speed Spindles in CNC machining centers and precision grinding machines
- High-frequency Electric Motors and servo drives
- Turbochargers and small gas turbine systems
- Precision instruments and medical device rotors
- High-performance robotics and automation equipment
