1 Complete Model & Code Explanation

Model: 7009 CE/P4ADT

Code Definition

7009: Light series precision angular contact ball bearing basic dimension

CE: 25° contact angle

P4A: Precision tolerance grade P4A

DT: Load-sorted single bearing for duplex assembly

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: High-carbon chromium 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: DT load-sorted specification, 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 high-carbon chromium bearing steel (all-steel bearing)

Seal: Open type, no seal

Note: The 25° contact angle provides strong axial load capacity, suitable for operating conditions with cutting axial thrust and radial loads. All-steel construction features good toughness and better impact resistance than hybrid ceramic bearings with cost advantages. Supplied as loose singles to facilitate flexible duplex spindle layouts. DT load sorting enables accurate preload control during assembly. Open design eliminates seal drag and fits oil-air lubrication. Independent lubrication system and external dust protection are required. Use bearings from the same batch for duplex installation to reduce load variation.

2 Structure & Operating Characteristics

Japan NMT 7009 CE/P4ADT is a size 7009 high-speed precision all-steel angular contact ball bearing. Inner rings, outer rings and balls are manufactured from premium bearing steel with ultra-precision grinding. The 25° contact angle strengthens axial load capacity to withstand combined radial and axial loads steadily. The all-steel design delivers high reliability, good impact resistance and convenient maintenance.

Supplied as non-pre-matched single bearings, engineers can freely adopt DB, DF or tandem duplex configurations. Bearings are load-sorted to DT grade; technicians adjust preload by spacers and shims. The low-friction open bearing is widely applied on machining center spindles, engraving & milling spindles, grinding spindles and other precision equipment subjected to axial cutting force.

3 Core Performance Advantages

1. 25° contact angle: Superior axial load capacity for combined radial and axial loads.

2. All-steel construction: Good toughness, resistance to minor impact, high cost performance and stable supply.

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

4. DT load-sorted duplex-capable single bearing: Flexible DB/DF/DT layout options with convenient preload adjustment.

5. Open unsealed structure: No seal resistance loss, fully compatible with oil-air high-speed lubrication.

5 Assembly Specifications & Usage Guidelines

5.1 Assembly Environment & Operation Standards

P4A precision bearings shall be assembled in dust-free clean surroundings. Remove all burrs and metal debris from shaft and housing mating surfaces. Controlled thermal mounting is recommended. Never strike bearing rings or steel balls directly. Select same-batch bearings for duplex assembly to minimize performance deviation.

5.2 Matching & Preload Instructions

No factory duplex assembly. All duplex layouts and target preload are set on-site with spacers and shims. DT sorting grade is only a reference standard. Measure spindle axial rigidity after assembly to verify actual preload. Excessive preload must be avoided to prevent overheating and premature fatigue damage.

5.3 Lubrication Matching Solutions

No pre-filled lubricant. Special 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 lubricants of different brands or types. Inspect lubrication pipelines regularly.

5.4 Speed Parameter Note

Obtain official load ratings and limiting speed data from SKF. Compared with hybrid ceramic bearings of the same size, its maximum DN value is relatively lower. Maintain sufficient safety margin based on load and cooling conditions, and reduce operating speed under heavy loads.

6 Daily Maintenance & Fault Troubleshooting

Carry out multi-stage low-speed running-in after assembly. Gradually increase rotating speed to rated value only after temperature rise and vibration stabilize. Open bearings have no built-in dust shield; labyrinth or air curtain dust-proof structure must be installed on equipment.

Ensure continuous and stable lubrication and prohibit dry friction. In case of abnormal temperature rise, noise or sharp vibration increase, check lubrication supply, mounting coaxiality, preload shim thickness, operating load and integrity of dust protection in sequence.