Manufactured by CHG Bearing, the S71905 ACEGA/HCP4A is a precision Super-precision Angular Contact Ball Bearings. Key dimensional parameters include a 25 mm bore diameter, a 42 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.

S71905 ACEGA/HCP4A - Super-precision Angular Contact Ball Bearings
Technical Specifications
| Overview | |
|---|---|
| Part Number | S71905 ACEGA/HCP4A |
| Brand | CHG® |
| Characteristics | |
| Bearing Type | Super-precision Angular Contact Ball Bearing |
| Seal Type | Non-contact Seal |
| 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 | Yes – Back-to-back (DB), Face-to-face (DF), or Tandem (DT) |
| Axial Clearance / Preload | Preload Class A |
| Tolerance Class | P4A |
| Bearing Material | Hybrid (Steel Rings / Ceramic Balls) |
| Sealing | Sealed on Both Sides |
| Lubricant | Grease |
| Dimensions | |
| Bore Diameter (d) | 25 mm |
| Width (B) | 9 mm |
| Outer Diameter (D) | 42 mm |
| Contact Angle α (°) | 25 ° |
| Performance | |
| Basic Dynamic Load Rating C (kN) | 5.07 kN |
| Basic Static Load Rating C₀ (kN) | 2.65 kN |
| Material | |
| Weight (kg) | 0.04 kg |
S71905 ACEGA/HCP4A 42 mm 25 mm 9 mm Frequently Asked Questions about S71905 ACEGA/HCP4A Super-precision Angular Contact Ball Bearings
Find key technical answers regarding dimensions, specifications, and replacement options for this model.
Quality starts with raw material selection: CHG Bearing crafts S71905 ACEGA/HCP4A inner and outer rings from high-purity High-Quality Chrome Steel (GCr15/100Cr6). Our raw billets undergo vacuum degassing and secondary ESR (electroslag remelting) processes to drastically eliminate non-metallic sulfide and oxide inclusions, elevating subsurface contact fatigue resistance.
Built for demanding industrial environments, the S71905 ACEGA/HCP4A Super-precision Angular Contact Ball Bearings by CHG Bearing boasts a dynamic load rating (Cr) of standard dynamic and a static load threshold (C0r) of standard static. The optimized internal raceway geometry balances stress distribution, mitigating edge loading even when operating under peak mechanical stresses.
Model S71905 ACEGA/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 25 mm) and steep thermal gradients between inner and outer rings.
As standard production, CHG Bearing subjects S71905 ACEGA/HCP4A 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.
