Product specifications

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

Core specifications14 parameters

Core specifications
Parameter	Symbol	Value
Series		31308
Bore diameter	d	40 mm
Outside diameter	D	90 mm
Width	B	25.25 mm
Basic dynamic load rating	C	94 kN
Basic static load rating	C0	83 kN
Fatigue load limit	Pu	12.3 kN
Reference speed	nref	5100 r/min
Limiting speed	nG	9600 r/min
Mass	≈m	0.72 kg
Precision class		PN — Normal (ISO 492:2023)
Cage		Standard — Sheet steel cage, window cage, roller-guided
Minimum operating temperature	Tmin	-30 °C
Maximum operating temperature	Tmax	120 °C

Product characteristics6 parameters

Product characteristics
Parameter	Symbol	Value
Tolerance class	PN	Normal (ISO 492:2023)
Heat treatment		Standard
Cage	Standard	Sheet steel cage, window cage, roller-guided
Internal design		Standard
Quality level	XL	X-life
Number of rows	1	Single-row design

Main Dimensions & Performance Data11 parameters

Main Dimensions & Performance Data
Parameter	Symbol	Value
Bore diameter	d	40 mm1.575 in
Outside diameter	D	90 mm3.543 in
Width, inner ring	B	23 mm0.906 in
Width, outer ring	C	17 mm0.669 in
Width, total	T	25.25 mm0.994 in
Basic dynamic load rating, radial	Cr	94,000 N21,133.094 lbf
Basic static load rating, radial	C0r	83,000 N18,660.072 lbf
Fatigue load limit, radial	Cur	12,300 N2,765.288 lbf
Limiting speed	nG	9,600 1/min
Thermal speed rating	nϑr	5,100 1/min
Mass	≈m	0.72 kg1.587 lbs

Mounting dimensions9 parameters

Mounting dimensions
Parameter	Symbol	Value
Maximum diameter of shaft shoulder	da max	51 mm2.008 in
Minimum diameter of shaft shoulder	db min	49 mm1.929 in
Minimum diameter of housing shoulder	Da min	71 mm2.795 in
Maximum diameter of housing shoulder	Da max	81 mm3.189 in
Minimum diameter of housing shoulder	Db min	86 mm3.386 in
Minimum axial space	Ca min	4 mm0.157 in
Minimum axial space	Cb min	8 mm0.315 in
Maximum fillet radius of shaft	ra max	2 mm0.079 in
Maximum fillet radius of housing	rb max	1.5 mm0.059 in

Dimensions4 parameters

Dimensions
Parameter	Symbol	Value
Minimum chamfer dimension of inner ring back face	r1, 2 min	2 mm0.079 in
Minimum chamfer dimension of outer ring back face	r3, 4 min	1.5 mm0.059 in
Distance between the apexes of the pressure cones	a	30 mm1.181 in
Guidance rib diameter of inner ring	d1	67.7 mm2.665 in

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	0.83
Dynamic axial load factor	Y	0.73
Static axial load factor	Y0	0.4

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 Identity10 parameters

Product Identity2 parameters

Product Identity
Parameter	Symbol	Value
Construction		Tapered roller bearings 313, main dimensions acc. to DIN 720, separable
Short Description		Tapered roller bearing

Additional information1 parameter

Additional information
Parameter	Symbol	Value
Comparative designation to ISO 10317 and ISO 355		T7FB040

Technical Data28 parameters

Technical Data
Parameter	Symbol	Value
Bore Diameter (D)		40 mm
Outside Diameter (D)		90 mm
Width (B)		25.25 mm
Basic Dynamic Load Rating, Radial (Cr)		94,000 N
Basic Static Load Rating, Radial (C0R)		83,000 N
Operating Temperature Min. (Tmin)		-30 °C
Limiting Speed (Ng)		9,600 1/min
Operating Temperature Max. (Tmax)		120 °C
Reference Speed (Nϑr)		5,100 1/min
Maximum Fillet Radius Of Housing (Rb Max)		1.5 mm
Minimum Chamfer Dimension Of Outer Ring Back Face (R3, 4 M)		1.5 mm
Minimum Diameter Of Housing Shoulder (Da Min)		71 mm
Minimum Diameter Of Housing Shoulder (Db Min)		86 mm
Width, Outer Ring (C)		17 mm
Fatigue Load Limit, Radial (Cur)		12,300 N
Limiting Value Of Fa/Fr For The Applicability Of Diff. Values Of Factors X And Y (E)		0.83
Maximum Diameter Of Shaft Shoulder (Da Max)		51 mm
Minimum Diameter Of Shaft Shoulder (Db Min)		49 mm
Maximum Diameter Of Housing Shoulder (Da Max)		81 mm
Dynamic Axial Load Factor (Y)		0.73
Maximum Fillet Radius (Ra Max)		2 mm
Minimum Axial Space (Cb Min)		8 mm
Minimum Chamfer Dimension Of Inner Ring Back Face (R1, 2 M)		2 mm
Guidance Rib Diameter Of Inner Ring (D1)		67.7 mm
Minimum Axial Space (Ca Min)		4 mm
Width, Inner Ring (B)		23 mm
Static Axial Load Factor (Y0)		0.4
Distance Between The Apexes Of The Pressure Cones (A)		30 mm

FAG 31308-XL