1 Complete Model, Dimensions, Loads & Technical Parameters

Full Model: 7005 CD/P4ADBA

Model Code Explanation

7005: Base specification of 70 series precision angular contact ball bearing;

CD: 15° contact angle, D-type high-load raceway geometry;

P4A: P4A ultra-precision tolerance grade;

DBA: Duplex Back-to-Back Arrangement, factory fixed back-to-back pre-matched duplex bearing set.

Standard Dimension Parameters

Bore d: 25 mm

Outer diameter D: 47 mm

Width B: 24 mm

Contact angle: 15 °

Load Performance Data

Basic dynamic load rating Cr: 15.6 kN

Basic static load rating C0r: 10.4 kN

Speed note: Contact SKF to obtain official technical documents for achievable operating speed

Full Product Attributes

Contact style: standard two-point contact

Row: 2 rows (duplex matched unit)

Race structure: integrated inner ring and outer ring

Internal design: D-type high-load optimized design

Interchangeable matched configuration: not available (fixed factory pairing, layout cannot be modified)

Matching arrangement: back-to-back <>

Quantity of bearings in set: 2 units

Preload / clearance specification: ultra-light preload

Tolerance class: P4A precision grade

Material: bearing steel

Coating: uncoated

Seal: open type without seals

Pre-filled lubricant: none, lubrication configured on demand

Indicative carbon footprint for new product: 0.57 kg CO₂e

Net weight: 0.154 kg

eClass code: 23-05-08-04

UNSPSC code: 31171531

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

2 Structure & Operating Characteristics

Japan NMT 7005 CD/P4ADBA is a 15° D-type high-load duplex fixed back-to-back pre-matched precision angular contact bearing with integrated bearing steel inner and outer rings. The 15° small contact angle fits high-speed applications. Optimized D-type high-load raceway enlarges contact area to raise load rating, balancing high rotational speed and load capacity. Supplied as factory screened and pre-matched duplex set with fixed back-to-back (<>) mounting arrangement. Preload and matching angle are locked at factory. Do not disassemble and reassemble into face-to-face or tandem layout.

Back-to-back arrangement features wider effective support span and excellent overturning resistance, suitable for shafts under combined radial load and large overturning moment. Ultra-light preload preset at factory reduces friction heat and maximizes limiting speed, ideal for high-speed medium-load equipment sensitive to temperature rise. Open non-sealed construction eliminates seal friction loss to deliver full high-speed performance. No pre-filled lubricant inside; high-speed grease or oil-air lubrication system is recommended.

Do not split the matched set and mix with other single bearings, otherwise preload balance will be destroyed, leading to higher vibration and rapid loss of rotational accuracy.

3 Core Performance Advantages

1. D-Type High-Load Raceway & 15° Contact Angle: Excellent load capacity combined with reliable high-speed performance, balancing load and speed requirements.

2. Factory Fixed Back-to-Back Duplex Pre-Matching: Locked matched status without on-site fitting; wide support span for superior overturning resistance.

3. Factory Ultra-Light Preload: Low friction and heat generation, outstanding limiting speed performance for spindles with strict temperature control.

4. High-Purity Bearing Steel: High hardness, good wear resistance, long contact fatigue life and stable dimensional stability for long-term service.

5. P4A Ultra-Precision Grade: Strict control over radial and axial runout to ensure long-term high-precision rotation.

6. Integrated Ring Structure: Sufficient overall rigidity and strong deformation resistance for long continuous stable operation.

7. Open Seal-Free Construction: No extra friction resistance, higher limiting speed, fully compatible with advanced oil-air lubrication solutions.

4 Typical Application Scenarios

4.1 Medium & Small High-Speed Precision Machine Tool Spindles: High-speed engraving & milling spindles, PCB high-speed drilling spindles, precision grinding spindles, high-speed woodworking spindles.

4.2 Heavy-Duty High-Speed Rotary Mechanisms for Automation: Precision indexing units, robot joints, high-speed winding rotary units requiring overturning resistance.

4.3 Optical & Precision Testing Equipment: High-precision optical scanning rotary platforms, rotary support assemblies for precision test fixtures.

4.4 Small Precision General Equipment: High-speed precision textile rotary shafts, high-speed rotary components for precision medical instruments.

5 Assembly Specifications & Usage Guidelines

5.1 Assembly Environment & Operation Standards

P4A high-precision duplex back-to-back pre-matched bearings must be assembled 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. This set is fixed DB pairing; disassembly and layout modification are forbidden. Control interference fit properly: excessive interference causes sharp temperature rise; insufficient interference leads to outer ring creep and damages preset preload.

5.2 Matching Structure & Preload Instructions

This model is factory pre-matched as fixed back-to-back (<>) configuration, DF and DT layouts are not supported. Back-to-back arrangement delivers longer effective pivot distance and stronger overturning resistance. Ultra-light preload suits high-speed applications with medium load and tight temperature control. Contact manufacturer for customization if alternative preload grade is required.

5.3 Lubrication Matching Solutions

No pre-filled lubricant inside bearing. High-speed low-viscosity grease applies to intermittent low-speed operation; oil-air circulating lubrication system is recommended for long continuous high-speed operation. Mixing different lubricant types is forbidden. Fully 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 bearing fatigue failure.

6 Daily Maintenance & Fault Troubleshooting

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

Replenish and replace lubricants periodically according to service cycle to maintain complete oil film on raceways. If continuous abnormal noise, accuracy decline or overheating occurs, sequentially check assembly interference, bearing mounting orientation, foreign matter intrusion and lubrication failure. Avoid severe impact loads to prevent permanent deformation of bearing rings.