Manufactured by CHG Bearing, the 71904 CD/P4A is a precision Super-precision Angular Contact Ball Bearings. Key dimensional parameters include a 20 mm bore diameter, a 37 mm outer diameter, and a 9 mm overall width. This component is designed to meet standard load requirements and ensure consistent operational performance. For comprehensive technical evaluation, please explore the detailed specifications, dimensional data, product images, and CAD drawings provided below. A complete PDF data sheet is also readily available for direct download to support your engineering and procurement needs.

71904 CD/P4A - Super-precision Angular Contact Ball Bearings
Technical Specifications
| Overview | |
|---|---|
| Part Number | 71904 CD/P4A |
| Brand | CHG® |
| Characteristics | |
| Bearing Type | Super-precision Angular Contact Ball Bearing |
| Number of Rows | 1 |
| Contact Type | Normal Contact (Two-point Contact) |
| Ring Type | Integral Inner and Outer Rings |
| Design | High-capacity D Design |
| Universally Matchable | No |
| Axial Clearance / Preload | Not Applicable |
| Tolerance Class | P4A |
| Bearing Material | Bearing Steel |
| Sealing | Open |
| Dimensions | |
| Bore Diameter (d) | 20 mm |
| Width (B) | 9 mm |
| Outer Diameter (D) | 37 mm |
| Contact Angle α (°) | 15 ° |
| Performance | |
| Basic Dynamic Load Rating C (kN) | 6.05 kN |
| Basic Static Load Rating C₀ (kN) | 3.2 kN |
| Limiting Speed – Grease (r/min) | 45000 r/min |
| Limiting Speed – Oil-air (r/min) | 67000 r/min |
| Material | |
| Weight (kg) | 0.036 kg |
71904 CD/P4A 37 mm 20 mm 9 mm Frequently Asked Questions about 71904 CD/P4A Super-precision Angular Contact Ball Bearings
Find key technical answers regarding dimensions, specifications, and replacement options for this model.
Following standard ISO 281 fatigue calculation guidelines, the nominal rating life (L10) of CHG Bearing 71904 CD/P4A correlates its dynamic capacity (standard dynamic) with equivalent dynamic loads. In controlled industrial settings with proper contamination-free filtration, field data confirms continuous operational longevity exceeding 20,000 to 50,000 service hours.
Absolutely. The CHG Bearing 71904 CD/P4A Super-precision Angular Contact Ball Bearings is a 1:1 direct interchange for renowned brands, matching part numbers: SKF 71904 CD/P4A, FAG 71904 CD/P4A, NSK 71904 CD/P4A. It shares identical envelope boundary dimensions, load capacities, and shaft fits, allowing instant drop-in replacement without retrofitting your machinery.
As standard production, CHG Bearing subjects 71904 CD/P4A to precision bainite or martensite quenching, offering dimensional stability up to 120°C (248°F). For high-heat processing equipment, CHG Bearing also supplies custom S0 (150°C), S1 (200°C), or S2 (250°C) stabilization heat treatments upon request to prevent residual austenite transformation.
In its sealed configuration (Open Type), CHG Bearing pre-charges 71904 CD/P4A with premium wide-temperature lithium-complex or polyurea grease, calibrated to a 30%–35% cavity volume ratio. For open-type variants, synthetic PAO or refined mineral lubricating oils with appropriate EP (Extreme Pressure) additives should be circulated.
