1 Complete Model & Code Explanation

Model: 7009 ACE/HCP4AQBCA

Code Definition

7009: Light series precision angular contact ball bearing basic dimension;

A: 25° contact angle;

CE: Hybrid ceramic construction (steel rings + Si₃N₄ ceramic balls);

HC: Hybrid Ceramic;

P4AQ: Ultra-precision tolerance grade P4AQ;

B: Measured load class B;

CA: Specification for duplex-capable single bearing.

Key Dimensions

Bore d: 45 mm

Outer diameter D: 75 mm

Width B: 16 mm

Contact angle: 25°

Structure: Single row open bearing

Rolling element: Silicon nitride ceramic ball

Ring material: Bearing steel

Supply form: Loose single unit, supports on-site DB/DF/DT duplex arrangement

Preload class: Measured load class B for shim adjustment

Pre-filled lubricant: None

Coating: None

Note: Contact SKF for load ratings and limiting speed data.

Full Product Attributes

Contact form: two-point contact

Number of rows: 1 (single bearing)

Duplex capable: Yes, back-to-back (<>), face-to-face (><), tandem (>>)

Factory duplex set: Not supplied (single loose unit)

Precision class: P4AQ ultra-precision grade

Material: Bearing steel rings + ceramic rolling elements (hybrid ceramic)

Seal: Open type, no seal

Note: The 25° contact angle provides superior axial load capacity for combined radial and heavy axial loads. Hybrid ceramic design reduces friction, heat generation and enables higher DN values. Lower mass of ceramic balls minimizes centrifugal force at high speed. Supplied as loose singles for flexible duplex spindle layout. Class B measured load grouping allows precise preload tuning via spacer shims. Open design eliminates seal drag and fits oil-air & high-speed grease lubrication. External dust protection is mandatory. Use same-batch bearings for duplex assembly.

2 Structure & Operating Characteristics

Japan NMT 7009 ACE/HCP4AQBCA is a size 7009 high-speed precision hybrid ceramic angular contact bearing. Bearing steel rings are ultra-precision raceway ground, paired with lightweight silicon nitride ceramic balls. The 25° contact angle balances radial and axial load capacity, ideal for spindles subjected to considerable axial cutting force.

Compared with all-steel bearings, hybrid ceramic construction achieves lower friction, less heat buildup and better anti-seizure performance, raising maximum operating speed. This duplex-capable single bearing is not factory-preassembled; users can configure duplex layouts according to spindle load requirements. Sorted to measured load Class B for convenient accurate preload setting. Open low-drag design is widely adopted for high-speed engraving, milling and grinding spindles.

3 Core Performance Advantages

1. 25° contact angle: Higher axial load capacity for applications with significant axial cutting loads.

2. Hybrid ceramic balls: Light weight, low friction, low temperature rise, suitable for high DN operation.

3. P4AQ ultra-precision grade: Strict rotary runout control for high-precision machining.

4. Duplex-capable single unit: Flexible DB/DF/DT duplex configuration.

5. Measured load Class B grouping: Convenient on-site preload adjustment by shims.

6. Open unsealed design: No seal power loss, compatible with oil-air high-speed lubrication.

4 Typical Application Scenarios

4.1 High-speed engraving & milling spindles, mold machining center spindles: High speed, heavy axial cutting loads, stable long-running low-temperature operation.

4.2 Precision internal/external grinders, tool grinder high-speed spindles: Continuous high rotation with strict limits on heat and vibration.

4.3 PCB drilling machines, high-speed precision automated rotary units: Long continuous high-speed operation requiring hybrid ceramic speed enhancement.

5 Assembly Specifications & Usage Guidelines

5.1 Assembly Environment & Operation Standards

P4AQ ultra-precision bearings must be assembled in dust-free cleanrooms. Remove all burrs and metal debris on shaft and housing mating surfaces. Controlled thermal mounting is recommended. Never strike bearing rings or ceramic rolling elements directly. Select bearings from identical batches for duplex assembly to reduce load scatter.

5.2 Matching & Preload Instructions

No factory duplex assembly. All duplex combinations and target preload shall be adjusted on-site using spacers and shims. Class B serves only as reference; measure spindle axial rigidity after assembly to verify real preload. Avoid excessive preload on ceramic bearings to prevent local stress damage to rolling elements.

5.3 Lubrication Matching Solutions

No pre-filled lubricant. Premium high-speed spindle grease works for intermittent high-speed operation. Oil-air lubrication is strongly recommended for continuous long-duration high-speed running to remove friction heat. Use lubricants specially formulated for ceramic rolling elements. Do not mix different lubricant types; maintain lubrication pipelines regularly.

5.4 Speed Parameter Note

Obtain official basic load ratings and limiting speed data from SKF. Although hybrid ceramic bearings excel at high speed, maintain sufficient safety margin depending on load and cooling; reduce operating speed under heavy loads.

6 Daily Maintenance & Fault Troubleshooting

Complete multi-stage low-speed running-in after assembly. Increase speed to rated range only after temperature and vibration stabilize. Open bearings have no built-in dust shield; labyrinth or air curtain dust protection must be installed on equipment.

Ensure continuous stable lubrication and prevent dry friction. In case of abnormal temperature rise, noise or vibration surge, inspect lubrication supply, mounting coaxiality, preload shim thickness, cutting load and integrity of dust protection sequentially.