1 Complete Model & Code Explanation

Model: 7009 CD/P4ADBC

Code Definition

7009: Light series precision angular contact ball bearing basic dimension

C: 15° contact angle

D: Open standard internal geometry, all-steel rolling elements

BC: Duplex-capable single bearing, measured load class B

P4A: Precision tolerance grade P4A

Key Dimensions

Bore d: 45 mm

Outer diameter D: 75 mm

Width B: 16 mm

Contact angle: 15°

Structure: Single row open bearing

Rolling element: Bearing steel ball

Ring material: High-carbon chromium bearing steel

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

Preload classification: Measured load class B, adjustable via spacer shims

Pre-filled lubricant: None

Coating: None

Note: Contact SKF for official 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 pre-assembled duplex set: Not supplied (loose single unit)

Precision class: P4A precision grade

Material: Full bearing steel (all-steel bearing)

Seal: Open type, no seal

Note: The 15° contact angle provides superior radial load capacity and low friction at high rotational speed, suited for applications dominated by radial loads with minor axial forces. All-steel construction delivers stable rigidity and broad lubricant compatibility. Supplied as loose singles to enable flexible duplex spindle layouts. Measured load Class B allows accurate preload tuning on site. Open design eliminates seal drag and works well with oil-air lubrication and long-life high-speed grease. Independent lubrication system and external dust protection are required. Use same-batch bearings for duplex assembly to minimize load scatter.

2 Structure & Operating Characteristics

Japan NMT 7009 CD/P4ADBC is a size 7009 high-speed precision all-steel angular contact ball bearing. Inner/outer rings and steel balls are manufactured from premium bearing steel with ultra-precision raceway grinding. The 15° contact angle optimizes radial load capacity and achieves excellent temperature control at high speed, ideal for high-speed engraving, precision grinding and high-speed rotary spindles.

The mature all-steel design ensures stable performance and wide lubrication compatibility. This duplex-capable bearing is delivered as separate single units without factory pre-assembly, allowing engineers to select DB, DF or tandem configurations freely. Bearings are sorted to measured load Class B; technicians can conveniently adjust preload using spacers and shims. The low-drag open structure is widely adopted for general precision spindle units requiring high rotating speed and consistent accuracy.

3 Core Performance Advantages

1. 15° contact angle: Excellent radial load capacity, low friction loss at high speed and higher limiting speed.

2. All-steel construction: Proven stable rigidity, broad lubricant compatibility and cost-effective performance.

3. P4A precision grade: Strict rotary runout control to sustain precision during long-term machining.

4. DBC duplex-capable single design: Flexible DB/DF/DT duplex layout options for spindle design.

5. Measured load Class B grouping: Convenient preload fine-tuning on site with adjustment shims.

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

4 Typical Application Scenarios

4.1 High-speed engraving & milling spindles, small machining center spindles

Continuous high-speed operation under predominant radial cutting loads and light axial forces.

4.2 Precision internal/external grinders, grinding wheel spindles

Requiring high rotational speed, low vibration and stable long-term operation.

4.3 High-speed rotary test fixtures, automated precision rotary mechanisms

Demanding high limiting speed and rotational accuracy with radial-dominant loads.

5 Assembly Specifications & Usage Guidelines

5.1 Assembly Environment & Operation Standards

P4A precision bearings must be assembled in dust-free clean conditions. Remove all burrs and metal debris from shaft and housing mating surfaces. Controlled thermal mounting is recommended. Never strike bearing rings or rolling balls directly. Select bearings from identical batches for duplex assembly to reduce performance variation.

5.2 Matching & Preload Instructions

No factory duplex assembly. All duplex arrangements and target preload are set on-site with spacers and shims. Class B serves only as reference; measure spindle axial rigidity after assembly to verify actual preload state. Excessive preload must be avoided to prevent overheating and premature raceway fatigue.

5.3 Lubrication Matching Solutions

No pre-filled lubricant. Specialized high-speed spindle grease is suitable for intermittent high-speed operation. Oil-air lubrication is preferred for continuous long-running high-speed applications to remove friction heat efficiently. Do not mix different types or brands of lubricants; inspect lubrication pipelines regularly.

5.4 Speed Parameter Note

Obtain official load ratings and limiting speed data from SKF. The 15° all-steel variant excels at high speed, yet sufficient safety margin should be reserved according to actual load and cooling conditions; reduce operating speed under heavy loads.

6 Daily Maintenance & Fault Troubleshooting

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

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