Product specifications

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

Core specifications12 parameters

Core specifications
Parameter	Symbol	Value
Series		K78215
Bore diameter	d	53.975 mm
Basic dynamic load rating	C	166 kN
Basic static load rating	C0	203 kN
Fatigue load limit	Pu	25 kN
Reference speed	nref	3950 r/min
Limiting speed	nG	5100 r/min
Mass	≈m	1.84 kg
Precision class		ABMA4 — Class 4 (ANSI/ABMA 19.2:2013)
Cage		Standard — Sheet steel cage, window cage, roller-guided
Minimum operating temperature	Tmin	-30 °C
Maximum operating temperature	Tmax	120 °C

Product characteristics5 parameters

Product characteristics
Parameter	Symbol	Value
Tolerance class	ABMA4	Class 4 (ANSI/ABMA 19.2:2013)
Heat treatment		Standard
Cage	Standard	Sheet steel cage, window cage, roller-guided
Quality level		Standard
Number of rows	1	Single-row design

Main Dimensions & Performance Data8 parameters

Main Dimensions & Performance Data
Parameter	Symbol	Value
Bore diameter	d	53.975 mm2.125 in
Width, inner ring	B	33.236 mm1.309 in
Basic dynamic load rating, radial	Cr	166,000 N37,320.144 lbf
Basic static load rating, radial	C0r	203,000 N45,638.489 lbf
Fatigue load limit, radial	Cur	25,000 N5,620.504 lbf
Limiting speed	nG	5,100 1/min
Thermal speed rating	nϑr	3,950 1/min
Mass	≈m	1.84 kg4.057 lbs

Mounting dimensions5 parameters

Mounting dimensions
Parameter	Symbol	Value
Maximum diameter of shaft shoulder	da max	77.5 mm3.051 in
Minimum diameter of shaft shoulder	db min	84 mm3.307 in
Minimum axial space	CRa min	7.3 mm0.287 in
Maximum axial space	CRb max	2.9 mm0.114 in
Maximum fillet radius of shaft	ra max	3.6 mm0.142 in

Dimensions5 parameters

Dimensions
Parameter	Symbol	Value
Minimum chamfer dimension of inner ring back face	r1, 2 min	3.6 mm0.142 in
Distance between the apexes of the pressure cones	a	42 mm1.654 in
Guidance rib diameter of inner ring	d1	101.6 mm4 in
Outer envelope circle	Ew	143.12 mm5.635 in
Contact angle	α	30 °

Temperature range2 parameters

Temperature range
Parameter	Symbol	Value
Operating temperature min.	Tmin	-30 °C-22 °F
Operating temperature max.	Tmax	120 °C248 °F

Calculation factors3 parameters

Calculation factors
Parameter	Symbol	Value
Limiting value of Fa/Fr for the applicability of diff. Values of factors X and Y	e	0.87
Dynamic axial load factor	Y	0.69
Static axial load factor	Y0	0.38

Capabilities & suitability5 parameters

Capabilities & suitability
Parameter	Symbol	Value
Radial load capacity		Yes
Axial load capacity in one direction		Yes
Suitable for grease lubrication		Yes
Suitable for oil lubrication		Yes
Unsealed design		Yes

Manufacturer Identity5 parameters

Product Identity2 parameters

Product Identity
Parameter	Symbol	Value
Construction		Tapered roller bearings without outer ring (Cone) K-Series, in inch sizes
Short Description		Tapered roller bearing

Technical Data21 parameters

Technical Data
Parameter	Symbol	Value
Bore Diameter (D)		53.975 mm
Basic Dynamic Load Rating, Radial (Cr)		166,000 N
Basic Static Load Rating, Radial (C0R)		203,000 N
Operating Temperature Min. (Tmin)		-30 °C
Limiting Speed (Ng)		5,100 1/min
Operating Temperature Max. (Tmax)		120 °C
Reference Speed (Nϑr)		3,950 1/min
Contact Angle (Α)		30 °
Fatigue Load Limit, Radial (Cur)		25,000 N
Limiting Value Of Fa/Fr For The Applicability Of Diff. Values Of Factors X And Y (E)		0.87
Maximum Diameter Of Shaft Shoulder (Da Max)		77.5 mm
Minimum Diameter Of Shaft Shoulder (Db Min)		84 mm
Dynamic Axial Load Factor (Y)		0.69
Maximum Fillet Radius (Ra Max)		3.6 mm
Maximum Axial Space (Crb Max)		2.9 mm
Minimum Chamfer Dimension Of Inner Ring Back Face (R1, 2 M)		3.6 mm
Guidance Rib Diameter Of Inner Ring (D1)		101.6 mm
Minimum Axial Space (Cra Min)		7.3 mm
Width, Inner Ring (B)		33.236 mm
Static Axial Load Factor (Y0)		0.38
Distance Between The Apexes Of The Pressure Cones (A)		42 mm

FAG K78215-C