7220AC Super Precision Angular Contact Bearings , Low Friction Ball Bearings

Product Specification

7220AC Angular Contact Ball Bearing  High-Load Precision Performance

Basic Parameters

• Bore diameter (d):100mm
• Outer diameter (D):180mm
• Width (B):34mm
• Contact angle:25° (suffix "AC" denotes standard angle)
• Weight:Approximately 3.6~3.8kg (typical range)
• Structure:Single-row, non-separable design with inner/outer rings and ball assembly. Cage options include brass solid cage (for high-speed stability) or pressed steel cage (for heavy-load scenarios).

Core Performance Specifications

1. Load Capacity
   • Dynamic load rating (Cr):132~140kN (typical range)
   • Static load rating (C0r):128~136kN (typical range)
   • Material:GCr15/SUJ2 high-carbon chromium bearing steel (surface hardness HRC58-62), with optional stainless steel (SUS440C) or ceramic (Si3N4 balls) variants for specialized environments.
2. Speed & Precision
   • Limiting speed:
     • Grease-lubricated: 3,200~3,600rpm (typical range)
     • Oil-lubricated: 4,300~4,800rpm (optimized for continuous high-speed operation)
   • Precision class:Standard P0 (customizable to P5/P4 for high-accuracy machinery, e.g., CNC spindles).
3. Technical Features
   • Axial-radial load capability:Supports combined radial loads and unidirectional axial thrust; paired installation (back-to-back or face-to-face) required for bidirectional axial loads.
   • Stability design:Optimized raceway curvature and cage geometry reduce friction and heat buildup during high-load, high-speed operation.

Structural & Environmental Adaptability

• Tolerance compatibility:
  • Shaft: H7/k6
  • Housing: J7
• Temperature range:
  • Standard: -20°C to 120°C
  • High-temperature variants: Up to 300°C with heat-resistant materials and lubricants.
• Sealing options:
  • Open design (standard)
  • Optional 2RS (rubber seals) or ZZ (metal shields) for dust, moisture, or debris protection.

Typical Applications

1. Industrial Machinery
   • Heavy-duty gearboxes:Handles radial and axial loads in mining, metallurgy, or construction equipment drivetrains.
   • Large-scale motors:Supports high torque in industrial pump or compressor shafts.
   • Wind turbine components:Used in pitch or yaw drives for 1.5MW+ wind generators.
2. Transportation
   • Commercial vehicle transmissions:Resists dynamic loads in truck or bus drivetrains.
   • Marine propulsion systems:Corrosion-resistant variants (SUS440C) for shipboard gearboxes.
3. Precision Equipment
   • CNC machine tool spindles:Provides rigidity for heavy milling or turning operations (with P5 precision customization).
   • Industrial robotics:Enables precise positioning in robotic arms handling medium-to-heavy payloads.

Maintenance & Lubrication Guidelines

• Lubrication:
  • Grease:Lithium-based grease (NLGI 2) with 15%-20% cavity filling; synthetic polyurea grease recommended for temperatures exceeding 120°C.
  • Oil:Circulating oil systems with ISO VG 32-68 oils for continuous high-speed operation to enhance heat dissipation.
• Inspection intervals:
  • Monitor vibration, temperature, and noise every 6-8 hours in heavy-duty cycles.
  • Replace lubricant every 4,000~8,000 hours, depending on load and environmental conditions.

Certifications & Compatibility

• Standards compliance:Meets ISO 9001:2015 and industry standards (e.g., ISO 281 for load ratings).
• Cross-brand compatibility:Interchangeable with equivalent standard models.

Summary

The 7220AC angular contact ball bearing balances high load capacity (up to 140kN dynamic), precision, and adaptability, making it ideal for heavy-duty industrial, transportation, and precision equipment. Its standardized design simplifies installation, while material and sealing options extend usability across diverse environments. With proper lubrication and maintenance, it delivers reliable performance in high-load, high-speed scenarios.

Note: Specific parameters may vary by production standards. Consult technical documentation for detailed specifications.