7021 ACD/P4A

The model number 7021 ACD/P4A provides detailed technical specifications through its suffixes.

• 7021: Basic bearing series, indicating a 105 mm bore, 160 mm outside diameter, and 26 mm width.
• A: Denotes a 25° contact angle, optimized for carrying high axial loads.
• CD: Signifies a matched arrangement (two bearings mounted as a duplex pair) with specific preload.
• P4A: Indicates the tolerance class. P4 is equivalent to ABEC-7, defining very high dimensional and running accuracy. The 'A' suffix may refer to specific deviations or special requirements within this class.

This bearing features an open design and is pre-lubricated for immediate use.

The design of the 7021 ACD/P4A translates directly into critical performance benefits for demanding applications.

• High Precision & Rigidity: Manufactured to P4 tolerance class, this bearing ensures minimal runout and vibration, providing the high rigidity required for precise positioning and finish in machine tool spindles.
• Superior Load Capacity: The 25° contact angle and robust construction using chrome steel for rings and balls enable it to handle high combined radial and axial loads effectively.
• Optimized High-Speed Performance: The lightweight phenolic resin cage offers excellent strength and guidance at high speeds, contributing to a high limiting speed. The open design facilitates efficient lubrication management.
• Preload & Matched Set: The CD matched arrangement ensures precise axial rigidity and rotational accuracy when mounted as a duplex pair, eliminating internal clearance and enhancing system stability.

The 7021 ACD/P4A is specified in high-performance machinery where precision, speed, and rigidity are paramount. Key applications include:

• Machine Tool Spindles: High-speed milling, grinding, and turning centers.
• Precision Spindles: PCB drilling machines, high-frequency motors.
• Robotics: High-accuracy joints and actuators.
• Aerospace & Defense Systems: Gyroscopes, radar equipment, and other precision instruments.