Manufactured by CHG Bearing, the 71904 ACDGC/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 ACDGC/P4A - Super-precision Angular Contact Ball Bearings
Technical Specifications
| Overview | |
|---|---|
| Part Number | 71904 ACDGC/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 | Yes – Back-to-back (DB), Face-to-face (DF), or Tandem (DT) |
| Axial Clearance / Preload | Preload Class C |
| 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 (°) | 25 ° |
| Performance | |
| Basic Dynamic Load Rating C (kN) | 5.72 kN |
| Basic Static Load Rating C₀ (kN) | 3.05 kN |
| Material | |
| Weight (kg) | 0.036 kg |
71904 ACDGC/P4A 37 mm 20 mm 9 mm Frequently Asked Questions about 71904 ACDGC/P4A Super-precision Angular Contact Ball Bearings
Find key technical answers regarding dimensions, specifications, and replacement options for this model.
To extend the trouble-free lifespan of CHG Bearing 71904 ACDGC/P4A, preventive maintenance routines should monitor operating housing temperature (normally maintaining below 70°C) and conduct regular vibration FFT analysis to identify early raceway micro-pitting before unexpected line halts occur.
Each 71904 ACDGC/P4A 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.
In its sealed configuration (Open Type), CHG Bearing pre-charges 71904 ACDGC/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.
When fitting 71904 ACDGC/P4A over a 20 mm shaft, CHG Bearing strictly recommends uniform induction heating (controlled between 90°C and 110°C) or precision hydraulic press sleeves. Under no circumstances should direct impact blows be struck against the rings or cage, as shock loads cause brinelling indents and premature spalling.
