Manufactured by CHG Bearing, the 71904 ACE/HCP4A 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 ACE/HCP4A - Super-precision Angular Contact Ball Bearings
Technical Specifications
| Overview | |
|---|---|
| Part Number | 71904 ACE/HCP4A |
| 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-speed E Design |
| Universally Matchable | No |
| Axial Clearance / Preload | Not Applicable |
| Tolerance Class | P4A |
| Bearing Material | Hybrid (Steel Rings / Ceramic Balls) |
| Sealing | Open |
| Dimensions | |
| Bore Diameter (d) | 20 mm |
| Width (B) | 9 mm |
| Outer Diameter (D) | 37 mm |
| Contact Angle α (°) | 25 ° |
| Performance | |
| Basic Dynamic Load Rating C (kN) | 4.68 kN |
| Basic Static Load Rating C₀ (kN) | 2.24 kN |
| Limiting Speed – Grease (r/min) | 60000 r/min |
| Limiting Speed – Oil-air (r/min) | 95000 r/min |
| Material | |
| Weight (kg) | 0.031 kg |
71904 ACE/HCP4A 37 mm 20 mm 9 mm Frequently Asked Questions about 71904 ACE/HCP4A Super-precision Angular Contact Ball Bearings
Find key technical answers regarding dimensions, specifications, and replacement options for this model.
In its sealed configuration (Open Type), CHG Bearing pre-charges 71904 ACE/HCP4A 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.
Model 71904 ACE/HCP4A is manufactured by CHG Bearing in standard Normal clearance (CN) for ambient temperature transmission, and C3 or C4 clearance for heavy duty applications. C3 clearance compensates for radial shrinkage caused by tight shaft press-fits (bore 20 mm) and steep thermal gradients between inner and outer rings.
The Open Type engineered for 71904 ACE/HCP4A by CHG Bearing utilizes precision non-contact metal shields or reinforced NBR/FKM contact lip seals. This barrier prevents particulate ingress, washdown fluids, and abrasive dust from reaching the raceways while eliminating grease leakage under centrifugal forces.
Each 71904 ACE/HCP4A produced in CHG Bearing manufacturing facilities features accurately profiled corner chamfers complying with DIN 5412 / ISO standard corner radii. When designing mating shafts and housing shoulders, machining an undercut or fillet radius strictly within the inner ring clearance limit (20 mm bore side) ensures perfect planar contact without edge binding.
