1 Complete Model, Dimensions, Loads & Technical Parameters

Full Model: 7004 FEGA/HCP4A

Model Code Explanation

7004: Base specification of 70 series precision angular contact bearing; FEGA: 18° contact angle, E-type high-speed two-point contact raceway geometry, Class A measured load preload standard; HCP4A: composite material, P4A ultra-precision tolerance grade. Single independent bearing, freely combinable for matched arrangements.

Standard Dimension Parameters

Bore d: 20 mm

Outer diameter D: 42 mm

Width B: 12 mm

Contact angle: 18 °

Load Performance Data

Basic dynamic load rating Cr: 7.41 kN

Basic static load rating C0r: 3.35 kN

Speed note: Contact SKF to obtain technical data of achievable operating speed

Full Product Attributes

Contact style: standard two-point contact

Row: 1 row (single independent unit)

Race structure: integrated inner ring, integrated outer ring

Internal design: E-type high-speed optimized design

Interchangeable matched configuration: available, back-to-back (<>), face-to-face (><), tandem (>>)

Matching arrangement: none (single unit, on-site free combination)

Quantity of bearings in set: 1 unit

Preload / clearance specification: measured load, Class A

Tolerance class: P4A precision grade

Material: composite material

Coating: uncoated

Seal: open type without seals

Pre-filled lubricant: none, lubrication configured on demand

Indicative carbon footprint for new product: 0.21 kg CO₂e

Net weight: 0.056 kg

eClass code: 23-05-08-03

UNSPSC code: 31171531

Speed note: Actual operating speed is affected by lubrication, heat dissipation, continuous load and assembly coaxiality. Confirm reference limiting speed with SKF before formal selection.

2 Structure & Operating Characteristics

Japan NMT 7004 FEGA/HCP4A is an 18° E-type high-speed single precision angular contact bearing with integrated composite inner and outer rings. The 18° small contact angle brings low friction and outstanding limiting speed, suitable for high-speed light-load applications. Optimized E-type high-speed raceway reduces rolling disturbance and suppresses temperature rise and vibration under high-speed operation. Supplied as single separate bearings without factory matching; multiple units can be combined on-site into back-to-back, face-to-face or tandem layouts according to shaft requirements.

Back-to-back (<>): wider support span and improved anti-overturning capacity;

Face-to-face (><): better tolerance for assembly coaxial error with compact structure;

Tandem (>>): superimposed axial load capacity for unidirectional axial thrust.

The bearing adopts Class A measured load standard for preload reference. Actual assembly preload can be precisely adjusted to balance high-speed rotational accuracy and friction heat generation. Open seal-free construction eliminates friction from seals to maximize speed potential. No pre-filled lubricant inside; high-speed grease or oil-air lubrication is recommended.

When multiple bearings work together, same-batch units are suggested to minimize individual differences affecting overall precision.

3 Core Performance Advantages

1. E-Type High-Speed Raceway & 18° Small Contact Angle: Low friction, excellent high-speed performance and effective temperature control.

2. Standard Single Independent Unit: Flexible free combination to satisfy various shaft layout solutions.

3. Class A Measured Load Standard: Standardized preload reference supporting accurate on-site preload adjustment.

4. Composite Material Body: Light weight, low rotational inertia, ideal for lightweight equipment and low carbon footprint.

5. P4A Ultra-Precision Grade: Strict control over radial and axial runout to guarantee high-speed precision rotation.

6. Integrated Ring Structure: Stable geometry, minimal deformation at high speed to sustain long-term precision.

7. Open Seal-Free Construction: No extra friction loss, suitable for high-speed operation and compatible with oil-air lubrication.

4 Typical Application Scenarios

4.1 Small Lightweight High-Speed Precision Spindles: Small engraving spindles, PCB high-speed machining spindles, compact precision grinding spindles, laboratory high-speed rotary spindles.

4.2 Light-Duty Automated High-Speed Rotary Mechanisms: Small precision indexing units, lightweight collaborative robot joints, high-speed winding and conveying rotary units.

4.3 Lightweight Precision Testing & Instrument Equipment: Optical inspection rotary platforms, precision test fixture rotary mechanisms, rotary support assemblies for small high-speed fluid equipment.

4.4 Small High-Speed General Precision Machinery: Mini high-speed textile rotary shafts, rotary support components for compact precision medical devices.

5 Assembly Specifications & Usage Guidelines

5.1 Assembly Environment & Operation Standards

P4A high-precision single precision bearings must be installed in dust-free clean environment. Remove burrs, dust and metal debris on shaft journals, housing bores and spacer mating surfaces. Thermal mounting is preferred. Direct impact on raceways, rolling elements and working surfaces is prohibited. Select bearings from the same batch for multi-bearing combinations. Control interference fit properly: excessive interference leads to sharp temperature rise; insufficient interference causes outer ring creep and destroys preload status.

5.2 Matching Structure & Preload Instructions

This model is an independent single bearing. Select back-to-back (<>), face-to-face (><) or tandem (>>) layouts according to load conditions. Calculate axial force and overturning moment of shaft system before assembly to confirm layout. The Class A measured load benchmark enables precise preload tuning via spacers and lock nuts. Factory pre-matched sets are available upon request to the manufacturer.

5.3 Lubrication Matching Solutions

No pre-filled lubricant inside bearing. High-speed low-viscosity grease is applicable for intermittent low-speed operation; oil-air circulating lubrication system is recommended for long-term continuous high-speed operation. Mixing different grades of lubricants is forbidden. Thoroughly clean bearing assembly before lubricant replacement.

5.4 Speed Parameter Note

Obtain reference limiting speed data directly from SKF. Reserve sufficient safety margin for continuous operation. Reduce operating speed under heavy load or poor heat dissipation to prevent premature fatigue failure.

6 Daily Maintenance & Fault Troubleshooting

Carry out low-speed no-load trial run after assembly, increase speed gradually, monitor vibration, noise and temperature rise. Formal operation can start only under stable working condition. Open design lacks built-in dust and coolant protection. External sealing must be installed at shaft end when dust, cutting fluid or moisture exists.

Replenish and replace lubricants periodically according to service cycle to maintain complete oil film on raceways. If continuous abnormal noise, precision decline or overheating occurs, sequentially inspect assembly interference, bearing layout, mounting direction, foreign particle intrusion and lubrication failure. Avoid severe impact loads which cause permanent ring deformation.