71920 ACD/P4ATBTA

• 71920: Basic series and size designation (Bore: 100mm, OD: 140mm, Width: 60mm).
• ACD: Angular Contact design with a 25° contact angle, optimized for combined loads.
• P4A: Denotes a super-precision tolerance class, exceeding ABEC 7/ISO P4 standards, for exceptional running accuracy.
• TB: Indicates bearings are matched and supplied in a Triplex Back-to-Back (TBT) arrangement.
• TA: Specifies the preload grade, here Extra light (Class A).

High Rigidity and Stability: The Triplex Back-to-Back (TBT) matched set configuration creates an extremely rigid bearing system, capable of withstanding complex combined loads (radial and axial) and overturning moments with minimal deflection.

Super-Precision Performance: Manufactured to P4A tolerance class, these bearings guarantee ultra-low runout and vibration, which is critical for achieving high surface finish quality and positional accuracy in machine tools.

Optimized High-Speed Capability: The combination of a phenolic resin cage, 25° contact angle, and extra light preload minimizes centrifugal forces and friction, enabling reliable operation at high limiting speeds (up to 15,000 rpm greased).

Superior Load Capacity: The robust chrome steel construction and optimized internal geometry provide high dynamic and static load ratings, ensuring long-term durability under demanding conditions.

This bearing is engineered for high-performance applications where extreme precision, rigidity, and speed are paramount. Key industries and machinery include:

• Machine Tool Spindles: High-speed milling, grinding, and turning centers.
• Precision Spindles: PCB drilling and routing spindles.
• High-Frequency Motors: Spindles for CNC machining.
• Robotics: High-accuracy rotary joints and arms.