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KOYO / Single-row / inch series

KOYO 3878/20

Tapered roller bearings technical reference with manufacturer-sourced dimensions, characteristics and engineering resources.

Technical data available
Bore diameterd
36.512 mm
Outside diameterD
85.725 mm
WidthB
30.162 mm
Dynamic load ratingC
135 kN
Static load ratingC0
136 kN
Limiting speednG
4800 r/min

Use this page as a technical reference. Verify the current manufacturer specification and the complete application requirements before selection.

Technical data

Product specifications

Metric and imperial values are paired where the manufacturer provides both. Expand a section to review its parameters.

Core specifications9 parameters
Core specifications
ParameterSymbolValue
Variant / constructionSingle-row / Inch series
Bore diameterd36.512 mm
Outside diameterD85.725 mm
WidthB30.162 mm
Basic dynamic load ratingC135 kN
Basic static load ratingC0136 kN
Fatigue load limitPu20.3 kN
Limiting speednG4800 r/min
Mass≈m0.89 kg
Manufacturer Identity2 parameters
Manufacturer Identity
ParameterSymbolValue
BrandKOYO
Official Class Key050-010-020
Classification2 parameters
Classification
ParameterSymbolValue
Official Category PathTapered roller bearings - Single-row - Inch series
Official Classification 1Tapered roller bearings / Single-row / Inch series
Technical Data23 parameters
Technical Data
ParameterSymbolValue
d36.512 mm
D85.725 mm
T30.162 mm
B30.162 mm
C23.812 mm
R(Min.)0.8 mm
R1(Min.)3.2 mm
Basic Load Ratings : Cr135 kN
Basic Load Ratings : C0R136 kN
Fatigue Load Limit : Cu20.3 kN
Limiting Speeds(Grease Lub.)4800 min-1
Limiting Speeds(Oil Lub.)6400 min-1
Load Center Spread : A22.9 mm
Constant :E0.40
Axial Load Factors : Y11.49
Axial Load Factors : Y00.82
Da48.0 mm
Db47.0 mm
Da73.0 mm
Db81.0 mm
Ra(Max.)0.8 mm
Rb(Max.)3.2 mm
Mass(Refer.)0.89 kg

Technical documents & data sheet

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Record identity
KOYO 3878/20
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