Original catalogue drawing - Timken TRB Catalog, page 658
Scanned from the manufacturer catalogue page listing this part number. All part numbers printed on that table share the same drawing.
Scale cross-section
Blue = inner / outer ring, yellow = rolling element. Drawn to scale from this part's own
dimensions for selection reference only - not a manufacturing or assembly drawing.
Dimension table (mm / inch)
Symbol
Dimension
mm
inch
d
Bore diameter
304.8
12
D
Outside diameter
438.048
17.246
T
Overall assembly width
161.925
6.375
C
Cup / outer-ring width
123.825
4.875
r
Chamfer (min)
1.5
0.0591
Notes
Tapered roller bearings are cone / cup assemblies; cone and cup weights are listed separately and the total is their sum. Weights are given in kg. Load ratings are shown in both the original catalogue units and the converted value (1 N = 0.2248 lbf). Data is provided for selection reference only - confirm against the latest official catalogue before ordering.
Main dimensions
Bore d (mm)
304.800
Bore d (in)
12.0000
Outside dia. D (mm)
438.048
Outside dia. D (in)
17.2460
Overall width T (mm)
161.925
Overall width T (in)
6.3750
Cup width C (mm)
123.825
Cup width C (in)
4.8750
Load ratings & speeds
Basic dynamic load rating Cr (lbs)
422000
Basic dynamic load rating Cr (N)
1880000
Dynamic rating C1 (N, ISO)
1880000
Dynamic rating C1 (lbf, ISO)
422000
Radial rating C90 (N)
280000
Radial rating C90 (lbf)
62900
Thrust rating Ca90 (N)
159000
Thrust rating Ca90 (lbf)
35700
Factor e
0.33
Factor Y1
2.04
Factor Y2
3.03
Factor K
1.76
Weight
Weight (kg)
71.44
Mounting dimensions (fillets / shoulders)
Shaft fillet R max (mm)
6.4
Housing fillet r max (mm)
1.5
Shaft shoulder db (mm)
333.0
Housing shoulder Da (mm)
414.1
Pin dimension Ka (mm)
22.23
Pin dimension Kb (mm)
11.12
Bearing life (ISO 281 basic rating life)
C / P
Equivalent load P (N)
L10 (106 rev)
L10h at 500 rpm
4
470,000
102
3,386
6
313,333
392
13,083
8
235,000
1,024
34,133
10
188,000
2,154
71,814
15
125,333
8,323
277,449
Basic rating life per ISO 281: L10 = (C/P)10/3 with C = 1,880,000 N. Hours = L10 x 106 / (60n). Life-modification factors for lubrication, contamination and temperature (aISO) are not included.
Source & traceability
Brand
Timken
Source catalogue
Timken Tapered Roller Bearing Catalog (2016)
Catalogue page
p.658 (dimensions)
Series type
TNA
ISO dynamic rating C1, Timken C90 / Ca90, static rating C0, geometry factors and assembly weight.
Send us the quantity you need and we will come back with price and
lead time, normally within 24 hours. Equivalent parts from other brands can be quoted at the same time.
