SKF bearing tolerances

The dimensional and running accuracy of SKF rolling bearings has been standardized internationally. In addition to the Normal tolerances, the ISO standards also cover closer tolerances, such as: 

  • tolerance class 6, which corresponds to SKF P6 tolerance class 
  • tolerance class 5, which corresponds to SKF P5 tolerance class

SKF bearing tolerance classes and the corresponding values for certain tolerance characteristics are specified in ISO 492 (for radial bearings) and ISO 199 (for thrust bearings). In 2014 these standards were aligned with general ISO GPS (Geometrical Product Specification) standards such as ISO 1101 and ISO 5459.

There are three common tolerance classes for SKF ball and roller bearings:

ISO tolerance class SKF designation suffix Description
Normal Minimum standard for all SKF ball and roller bearings.
Class 6 P6 Tighter tolerances than Normal. 
Class 5 P5 Tighter tolerances than class 6. 

For special applications like machine tool spindles, SKF also manufactures bearings with higher accuracy. These include the P4, P4A, PA9A, SP and UP tolerance classes.

For tolerance information about each bearing type, refer to Tolerances in the relevant product section. Bearings with higher accuracy than Normal are typically identified by a designation suffix for the tolerance class.

The tolerance symbols and their definitions are provided in Bearing tolerances symbols.

SKF bearing tolerance values

Actual SKF bearing tolerances values are listed in the following tables.

SKF metric radial bearings tolerances

Normal tolerances

Normal tolerances for SKF radial bearings, except tapered roller bearings

Inner ring

d tΔdmp tVdsp tVdmp tΔBs tVBs tKia
    Diameter series   All Normal Modified3)    
> U L 7, 8, 92) 0, 1    2, 3, 4   U L L    
mm μm μm μm μm μm μm
2,5 0 –8 10 8 6 6 0 –40 12 10
2,5 10 0 –8 10 8 6 6 0 –120 –250 15 10
10 18 0 –8 10 8 6 6 0 –120 –250 20 10
18 30 0 –10 13 10 8 8 0 –120 –250 20 13
30 50 0 –12 15 12 9 9 0 –120 –250 20 15
50 80 0 –15 19 19 11 11 0 –150 –380 25 20
80 120 0 –20 25 25 15 15 0 –200 –380 25 25
120 180 0 –25 31 31 19 19 0 –250 –500 30 30
180 250 0 –30 38 38 23 23 0 –300 –500 30 40
250 315 0 –35 44 44 26 26 0 –350 –500 35 50
315 400 0 –40 50 50 30 30 0 –400 –630 40 60
400 500 0 –45 56 56 34 34 0 –450 50 65
500 630 0 –50 63 63 38 38 0 –500 60 70
630 800 0 –75 0 –750 70 80
800 1 000 0 –100 0 –1 000 80 90
1 000 1 250 0 –125 0 –1 250 100 100
1 250 1 600 0 –160 0 –1 600 120 120
1 600 2 000 0 –200 0 –2 000 140 140

Outer ring

D tΔDmp tVDsp tVDmp tΔCs tKea
    Open bearings 
Diameter series
Capped bearings   tVCs  
> U L 7, 8, 9 0, 1 2, 3, 4 2, 3, 4      
mm μm μm μm μm μm
2,5 18 0 –8 10 8 6 10 6 Identical to 
tΔBs and tVBs
of an inner ring 
of the same 
bearing as the 
outer ring
15
18 30 0 –9 12 9 7 12 7 15
30 50 0 –11 14 11 8 16 8 20
 
50 80 0 –13 16 13 10 20 10 25
80 120 0 –15 19 19 11 26 11 35
120 150 0 –18 23 23 14 30 14 40
150 180 0 –25 31 31 19 38 19 45
180 250 0 –30 38 38 23 23 50
250 315 0 –35 44 44 26 26 60
315 400 0 –40 50 50 30 30 70
400 500 0 –45 56 56 34 34 80
500 630 0 –50 63 63 38 38 100
630 800 0 –75 94 94 55 55 120
800 1 000 0 –100 125 125 75 75 140
1 000 1 250 0 –125 160
1 250 1 600 0 –160 190
1 600 2 000 0 –200 220
2 000 2 500 0 –250 250

P6 class tolerances

P6 class tolerances for SKF radial bearings, except tapered roller bearings

Inner ring

d tΔdmp tVdsp tVdmp tΔBs tVBs tKia
    Diameter series   All Normal Modified3)  
> U L 7, 8, 92) 0, 1   2, 3, 4   U L L    
mm μm μm μm μm μm μm
2,5 0 –7 9 7 5 5 0 –40 12 5
2,5 10 0 –7 9 7 5 5 0 –120 –250 15 6
10 18 0 –7 9 7 5 5 0 –120 –250 20 7
18 30 0 –8 10 8 6 6 0 –120 –250 20 8
30 50 0 –10 13 10 8 8 0 –120 –250 20 10
50 80 0 –12 15 15 9 9 0 –150 –380 25 10
80 120 0 –15 19 19 11 11 0 –200 –380 25 13
120 180 0 –18 23 23 14 14 0 –250 –500 30 18
180 250 0 –22 28 28 17 17 0 –300 –500 30 20
250 315 0 –25 31 31 19 19 0 –350 –500 35 25
315 400 0 –30 38 38 23 23 0 –400 –630 40 30
400 500 0 –35 44 44 26 26 0 –450 45 35
500 630 0 –40 50 50 30 30 0 –500 50 40
630 800 0 –50 0 –750 60  45
800 1 000 0 –60 0 –1 000 60 50
1 000 1 250 0 –75 0 –1 250 70 60
1 250 1 600 0 –90 0 –1 600 70 70
1 600 2 000 0 –115 0 –2 000 80 80

Outer ring

D tΔDmp tVDsp   tVDmp tΔCs tKea
    Open bearings 
Diameter series
Capped bearings5)     tVCs  
> U L 7, 8, 92) 0, 1 2, 3, 4 0, 1, 2, 3, 4       
mm μm μm μm μm   μm
2,5 18 0 –7 9 7 5 9   5 Identical to 
tΔBs and tVBs
of an inner ring 
of the same 
bearing as the 
outer ring
8
18 30 0 –8 10 8 6 10   6 9
30 50 0 –9 11 9 7 13   7 10
50 80 0 –11 14 11 8 16   8 13
80 120 0 –13 16 16 10 20   10 18
120 150 0 –15 19 19 11 25   11 20
150 180 0 –18 23 23 14 30   14 23
180 250 0 –20 25 25 15   15 25
250 315 0 –25 31 31 19   19 30
315 400 0 –28 35 35 21   21 35
400 500 0 –33 41 41 25   25 40
500 630 0 –38 48 48 29   29 50
630 800 0 –45 56 56 34   34 60
800 1 000 0 –60 75 75 45   45 75
1 000 1 250 0 –75   85
1 250 1 600 0 –90   100
1 600 2 000 0 –115   100
2 000 2 500 0 –135   120

P5 class tolerances

P5 class tolerances for SKF radial bearings, except tapered roller bearings

Inner ring

d tΔdmp tVdsp tVdmp tΔBs tVBs tKia tSd tSia
  Diameter series  
    7, 8, 92) 0, 1, 2, 3, 4   All Normal Modified4)  
> U L       U L L  
mm μm μm μm μm μm μm μm μm
2,5 0 –5 5 4 3 0 –40 –250 5 4 7 7
2,5 10 0 –5 5 4 3 0 –40 –250 5 4 7 7
10 18 0 –5 5 4 3 0 –80 –250 5 4 7 7
18 30 0 –6 6 5 3 0 –120 –250 5 4 8 8
30 50 0 –8 8 6 4 0 –120 –250 5 5 8 8
50 80 0 –9 9 7 5 0 –150 –250 6 5 8 8
80 120 0 –10 10 8 5 0 –200 –380 7 6 9 9
120 180 0 –13 13 10 7 0 –250 –380 8 8 10 10
180 250 0 –15 15 12 8 0 –300 –500 10 10 11 13
250 315 0 –18 18 14 9 0 –350 –500 13 13 13 15
315 400 0 –23 23 18 12 0 –400 –630 15 15 15 20
400 500 0 –28 28 21 14 0 –450 18 17 18 23
500 630 0 –35 35 26 18 0 –500 20 19 20 25
630 800 0 –45 0 –750 26 22 26 30
800 1 000 0 –60 0 –1 000 32 26 32 30
1 000 1 250 0 –75 0 –1 250 38 30 38 30
1 250 1 600 0 –90 0 –1 600 45 35 45 30
1 600 2 000 0 –115 0 –2 000 55 40 55 30

Outer ring

D tΔDmp tVDsp tVDmp tΔCs tVCs tKea tSD tSea
  Diameter series  
> U L 7, 8, 92) 0, 1, 2, 3, 4  
mm μm μm μm μm μm μm μm μm
2,5 18 0 –5 5 4 3 Identical to 
tΔBsof an 
inner ring of 
the same 
bearing as the 
outer ring
5 5 4 8
18 30 0 –6 6 5 3 5 6 4 8
30 50 0 –7 7 5 4 5 7 4 8
50 80 0 –9 9 7 5 6 8 4 10
80 120 0 –10 10 8 5 8 10 4,5 11
120 150 0 –11 11 8 6 8 11 5 13
150 180 0 –13 13 10 7 8 13 5 14
180 250 0 –15 15 11 8 10 15 5,5 15
250 315 0 –18 18 14 9 11 18 6,5 18
315 400 0 –20 20 15 10 13 20 6,5 20
400 500 0 –23 23 17 12 15 23 7,5 23
500 630 0 –28 28 21 14 18 25 9 25
630 800 0 –35 35 26 18 20 30 10 30
800 1 000 0 –50 50 29 25 25 35 12,5
1 000 1 250 0 –63 30 40 15
1 250 1 600 0 –80 35 45 17,5
1 600 2 000 0 –100 38 55 20
2 000 2 500 0 –125 45 65 25

SKF metric tapered roller bearings tolerances

Normal and CL7C class tolerances

Normal and CL7C class tolerances for SKF metric tapered roller bearings

Inner ring, bearing width and ring widths

d tΔdmp tVdsp tVdmp tΔBs tKia tΔTs tΔT1s tΔT2s
          Tolerance classes      
          Normal CL7C1)      
> U L     U L     U L U L U L
mm μm μm μm μm μm μm μm μm
10 18 0 –12 12 9 0 –120 15 7 +200 0 +100 0 +100 0
18 30 0 –12 12 9 0 –120 18 8 +200 0 +100 0 +100 0
30 50 0 –12 12 9 0 –120 20 10 +200 0 +100 0 +100 0
50 80 0 –15 15 11 0 –150 25 10 +200 0 +100 0 +100 0
80 120 0 –20 20 15 0 –200 30 13 +200 –200 +100 –100 +100 –100
120 180 0 –25 25 19 0 –250 35 +350 –250 +150 –150 +200 –100
180 250 0 –30 30 23 0 –300 50 +350 –250 +150 –150 +200 –100
250 315 0 –35 35 26 0 –350 60 +350 –250 +150 –150 +200 –100
315 400 0 –40 40 30 0 –400 70 +400 –400 +200 –200 +200 –200

Outer ring

D tΔDmp tVDsp tVDmp tΔCs tKea
          Tolerance classes
          Normal CL7C1)
> U L     U L    
mm μm μm μm μm μm
18 30 0 –12 12 9 0 –120 18 9
30 50 0 –14 14 11 0 –120 20 10
50 80 0 –16 16 12 0 –150 25 13
80 120 0 –18 18 14 0 –200 35 18
120 150 0 –20 20 15 0 –250 40 20
150 180 0 –25 25 19 0 –250 45 23
180 250 0 –30 30 23 0 –300 50
250 315 0 –35 35 26 0 –350 60
315 400 0 –40 40 30 0 –400 70
400 500 0 –45 45 34 0 –450 80
500 630 0 –50 60 38 0 –500 100
630 800 0 –75 80 55 0 –750 120

CLN class tolerances

CLN class tolerances for SKF metric tapered roller bearings. Tolerance class CLN is in accordance with ISO tolerance class 6X.

Inner ring, bearing width and ring widths

d tΔdmp tVdsp tVdmp tΔBs tKia tΔTs tΔT1s tΔT2s
> U L   U L   U L U L U L
mm μm μm μm μm μm μm μm μm
10 18 0 –12 12 9 0 –50 15 +100 0 +50 0 +50 0
18 30 0 –12 12 9 0 –50 18 +100 0 +50 0 +50 0
30 50 0 –12 12 9 0 –50 20 +100 0 +50 0 +50 0
50 80 0 –15 15 11 0 –50 25 +100 0 +50 0 +50 0
80 120 0 –20 20 15 0 –50 30 +100 0 +50 0 +50 0
120 180 0 –25 25 19 0 –50 35 +150 0 +50 0 +100 0
180 250 0 –30 30 23 0 –50 50 +150 0 +50 0 +100 0
250 315 0 –35 35 26 0 –50 60 +200 0 +100 0 +100 0
315 400 0 –40 40 30 0 –50 70 +200 0 +100 0 +100 0

Outer ring

D tΔDmp tVDsp tVDmp tΔCs tKea
> U L   U L  
mm μm μm μm μm μm
18 30 0 –12 12 9 0 -100 18
30 50 0 –14 14 11 0 -100 20
50 80 0 –16 16 12 0 -100 25
80 120 0 –18 18 14 0 -100 35
120 150 0 –20 20 15 0 -100 40
150 180 0 –25 25 19 0 -100 45
180 250 0 –30 30 23 0 -100 50
250 315 0 –35 35 26 0 -100 60
315 400 0 –40 40 30 0 -100 70
400 500 0 –45 45 34 0 -100 80
500 630 0 –50 60 38 0 -100 100

P5 class tolerances

P5 class tolerances for SKF metric tapered roller bearings

Inner ring and bearing width

d tΔdmp tVdsp tVdmp tΔBs tKia tSd tΔTs tΔT1s tΔT2s
> U L   U L   U L U L U L
mm μm μm μm μm μm μm μm μm μm
10 18 0 –7 5 5 0 –200 5 7 +200 –200 +100 –100 +100 –100
18 30 0 –8 6 5 0 –200 5 8 +200 –200 +100 –100 +100 –100
30 50 0 –10 8 5 0 –240 6 8 +200 –200 +100 –100 +100 –100
50 80 0 –12 9 6 0 –300 7 8 +200 –200 +100 –100 +100 –100
80 120 0 –15 11 8 0 –400 8 9 +200 –200 +100 –100 +100 –100
120 180 0 –18 14 9 0 –500 11 10 +350 –250 +150 –150 +200 –100
180 250 0 –22 17 11 0 –600 13 11 +350 –250 +150 –150 +200 –100
250 315 0 –25 19 13 0 –700 13 13 +350 –250 +150 –150 +200 –100
315 400 0 –30 23 15 0 –800 15 15 +400 –400 +200 –200 +200 –200
400  500  -35  28  17  -900  20  17  +450  -450  +225  -225  +225  -225 
500  630 

-40

35  20  -1 100  25  20  +500  -500  –  – 
630  800  -50  45  25  -1 600  30  25  +600  -600 
800  1 000  -60  60  30  -2 000  37  30  +750  -750  – 
1 000  1 250  -75  75  37  -2 000  45  40  +750  -750 
1 250  1 600  -90  90  45  -2 000  55  50  +900  -900 

Outer ring

D tΔDmp tVDsp tVDmp tΔCs tKea tSD1)
> U L  
mm μm μm μm   μm μm
18 30 0 –8 6 5 Identical to 
tΔBs of an 
inner ring of the 
same bearing as 
the outer ring
6 4
30 50 0 –9 7 5 7 4
50 80 0 –11 8 6 8 4
80 120 0 –13 10 7 10 4,5
120 150 0 –15 11 8 11 5
150 180 0 –18 14 9 13 5
180 250 0 –20 15 10 15 5,5
250 315 0 –25 19 13 18 6,5
315 400 0 –28 22 14 20 6,5
400 500 0 –33 26 17 24 8,5
500 630 0 –38 30  20  30 10
630  800  -45  38  25  36  12,5 
800  1 000  -60  50  30  43  15 
1 000  1 250  -80  65  38  52  19 
1 250  1 600  -100  90  50  62  25 
1 600  2 000  -125  120  65  73  32,5

SKF inch radial bearings tolerances, except tapered roller bearings: 

Normal tolerances

Normal tolerances for SKF inch radial bearings, except tapered roller bearings

Inner ring

d tΔdmp tVdsp tΔBs tVBs tKia tSia
> U L   U L  
mm μm μm μm μm μm μm
25,4 +5 –5 10 0 –127 13 10 15
25,4 50,8 +5 –8 10 0 –127 13 10 20
50,8 76,2 +5 –8 13 0 –127 13 15 30
76,2 152,4 +5 –8 18 0 –127 15 20 38
152,4 203,2 +5 –13 33 0 –127 15 25 51
203,2 304,8 +5 –13 33 0 –254 20 30 51
304,8 381 +5 –20 51 0 –406 25 38 64

Outer ring

D tΔDmp tVDsp tΔCs tVCs tKea tSea
> U L      
mm μm μm μm μm μm μm
25,4 –8 –18 10 Identical to 
tΔBs
of an inner ring 
of the same 
bearing as the 
outer ring
13 10 15
25,4 50,8 –8 –20 10 13 13 15
50,8 76,2 –13 –25 13 13 15 20
76,2 127 –20 –33 18 15 18 30
127 203,2 –33 –46 33 15 20 38
203,2 304,8 –33 –46 33 20 25 51
304,8 381 –33 –58 51 25 30 51
381 508 –33 –58 51 30 38 64

SKF inch tapered roller bearings

Normal, CL2, CL3 and CL0 class tolerances

Tolerances for SKF inch tapered roller bearings

Inner ring

d tΔdmp tKia, tSia  
  Tolerance classes    
  Normal, CL2 CL3, CL0    
> U L U L  
mm μm μm  
76,2 +13 0 +13 0 Values are 
given in 
outer ring table
76,2 101,6 +25 0 +13 0
101,6 266,7 +25 0 +13 0
266,7 304,8 +25 0 +13 0
304,8 609,6 +51 0 +25 0
609,6 914,4 +76 0 +38 0

Outer ring

D tΔDmp tKia, tKea, tSia, tSea tKea
  Tolerance classes Tolerance classes Tolerance class
  Normal, CL2 CL3, CL0 Normal CL2 CL3 CL0 CL7C
> H L H L  
mm μm μm μm  
304,8 +25 0 +13 0 51 38 8 4  
304,8 609,6 +51 0 +25 0 51 38 18 9  
609,6 914,4 +76 0 +38 0 76 51 51 26  

Abutment width of single row bearing

d D tΔTs
    Tolerance classes
    Normal CL2 CL3, CL0
> > U L U L U L
mm mm μm μm μm
101,6 +203 0 +203 0 +203 –203
101,6 266,7 +356 –254 +203 0 +203 –203
266,7 304,8 +356 –254 +203 0 +203 –203
304,8 609,6 508 +381 –381 +381 –381 +203 –203
304,8 609,6 508 +381 –381 +381 –381 +381 –381
609,6 +381 –381 +381 –381

SKF thrust bearings tolerances

Normal, P6 and P5 class tolerances

Tolerances for SKF thrust bearings

Nominal 
diameter
  Shaft washer   Housing washer
    Tolerance classes   Tolerance classes   Tolerance classes
d, d2, D1)   Normal, P6, P5   Normal P6 P5   Normal, P6, P5
    tΔdmp, tΔd2mp tVdsp, tVd2sp   tSi tSi tSi   tΔDmp tVDsp tSe
>   U L             U L    
mm   μm μm   μm μm μm   μm μm  
18   0 –8 6   10 5 3   0 –11 8 Identical to 
tSi of shaft 
washer of 
same bearing
18 30   0 –10 8   10 5 3   0 –13 10
30 50   0 –12 9   10 6 3   0 –16 12
50 80   0 –15 11   10 7 4   0 –19 14
80 120   0 –20 15   15 8 4   0 –22 17
120 180   0 –25 19   15 9 5   0 –25 19
180 250   0 –30 23   20 10 5   0 –30 23
250 315   0 –35 26   25 13 7   0 –35 26
315 400   0 –40 30   30 15 7   0 –40 30
400 500   0 –45 34   30 18 9   0 –45 34
500 630   0 –50 38   35 21 11   0 –50 38
630 800   0 –75 55   40 25 13   0 –75 55
800 1 000   0 –100 75   45 30 15   0 –100 75
1 000 1 250   0 –125 95   50 35 18   0 –125 95
1 250 1 600   0 –160 120   60 40 25   0 –160 120
1 600 2 000   0 –200 150   75 45 30   0 –200 150
2 000 2 500   0 –250 190   90 50 40    0 –250 190

Bearing height

d, d21) tΔTs tΔT1s tΔT1s tΔT3s tΔT4s
  Single direction 
bearings without 
seat washer
Single direction 
bearings with 
seat washer
Double direction 
bearings without 
seat washers
Double direction 
bearings with 
seat washers
Spherical roller 
thrust bearings
 
          SKF SKF Explorer
> U L U L U L U L U L U L
mm μm μm μm μm μm
30 +20 –250 +100 –250 +150 –400 +300 –400
30 50 +20 –250 +100 –250 +150 –400 +300 –400
50 80 +20 –300 +100 –300 +150 –500 +300 –500 0 –125 0 –100
80 120 +25 –300 +150 –300 +200 –500 +400 –500 0 –150 0 –100
120 180 +25 –400 +150 –400 +200 –600 +400 –600 0 –175 0 –125
180 250 +30 –400 +150 –400 +250 –600 +500 –600 0 –200 0 –125
250 315 +40 –400 0 –225 0 –150
315 400 +40 –500 0 –300 0 –200
400 500 +50 –500 0 –400
500 630 +60 –600 0 –500
630 800 +70 –750 0 –630
800 1 000 +80 –1 000 0 –800
1 000 1 250 +100 –1 400 0 –1 000
1 250 1 600 +120 –1 600 0 –1 200
1 600 2 000 +140 –1 900
2 000 2 500 +160 –2 300

SKF tapered bore bearings tolerances, taper 1:12

Normal, P6 and P5 class tolerances

Normal, P6 and P5 class tolerances for SKF tapered bores bearings, taper 1:12

Normal, P6 and P5 class tolerances for SKF tapered bores bearings, taper 1:12

Bore diameter Tolerance classes
  Normal, P6 P5
d tΔdmp tVdsp tΔSL tΔdmp tVdsp tΔSL
> U L   U L U L   U L
mm μm μm μm μm μm μm
18 30 +21 0 13 +21 0 +13 0 13 +13 0
30 50 +25 0 15 +25 0 +16 0 15 +16 0
50 80 +30 0 19 +30 0 +19 0 19 +19 0
80 120 +35 0 22 +35 0 +22 0 22 +22 0
120 180 +40 0 31 +40 0 +25 0 25 +25 0
180 250 +46 0 38 +46 0 +29 0 29 +29 0
250 315 +52 0 44 +52 0 +32 0 32 +32 0
315 400 +57 0 50 +57 0 +36 0 36 +36 0
400 500 +63 0 56 +63 0 +40 0 +40 0
500 630 +70 0 70 +70 0 +44 0 +44 0
630 800 +80 0 +80 0 +50 0 +50 0
800 1 000 +90 0 +90 0 +56 0 +56 0
1 000 1 250 +105 0 +105 0 +66 0 +66 0
1 250 1 600 +125 0 +125 0 +78 0 +78 0
1 600 2 000 +150 0 +150 0 +92 0 +92 0

SKF tapered bore bearings tolerances, taper 1:30

Normal tolerances

Bore diameter Tolerance class
  Normal  
d tΔdmp tVdsp1) tΔSL
> U L   U L
mm μm μm μm
80 +15 0 19 +30 0
80 120 +20 0 22 +35 0
120 180 +25 0 40 +40 0
180 250 +30 0 46 +46 0
250 315 +35 0 52 +52 0
315 400 +40 0 57 +57 0
400 500 +45 0 63 +63 0
500 630 +50 0 70 +70 0
630 800 +75 0 +100 0
800 1 000 +100 0 +100 0
1 000 1 250 +125 0 +115 0
1 250 1 600 +160 0 +125 0
1 600 2 000 +200 0 +150 0

SKF bearing tolerance symbols

The tolerance symbols that we use are in line with ISO 492 and ISO 199 and are explained in the tables as follows. The symbols normally refer to dimensional tolerances, only Kia, Kea, Sd, SD, Sia and Sea refer to geometrical tolerances.

Tolerance
symbol
Definition
  Radial bearings inner ring - cylindrical and tapered bore
 
d
  1. Cylindrical bore: Nominal bore diameter
  2. Tapered bore: Nominal bore diameter at the theoretical small end
Δdmp
  1. Cylindrical bore: Deviation of a mid-range size (out of two-point sizes) of bore diameter in any cross section from its nominal size
  2. Tapered bore: Deviation of a mid-range size (out of two-point sizes) of bore diameter at the theoretical small end from its nominal size
Δds Deviation of a two-point size of bore diameter of a cylindrical bore from its nominal size
Vdsp Range of two-point sizes of bore diameter in any cross section of a cylindrical or tapered bore
Vdmp Range of mid-range sizes (out of two-point sizes) of bore diameter obtained from any cross section of a cylindrical bore
B Nominal inner ring width
ΔBs
Normal, 
Modified1)
  1. Symmetrical rings: Deviation of a two-point size of inner ring width from its nominal size
  2. Asymmetrical rings, upper limit: Deviation of a minimum circumscribed size of inner ring width, between two opposite lines, in any longitudinal section which includes the inner ring bore axis, from its nominal size
  3. Asymmetrical rings, lower limit: Deviation of a two-point size of inner ring width from its nominal size
VBs
  1. Symmetrical rings: Range of two-point sizes of inner ring width
  2. Asymmetrical rings: Range of minimum circumscribed sizes of inner ring width, between two opposite lines, obtained from any longitudinal section which includes the inner ring bore axis
Kia4) Circular radial run-out of inner ring bore surface of assembled bearing with respect to datum, i.e. axis, established from the outer ring outside surface

Sd4)

Circular axial run-out of inner ring face with respect to datum, i.e. axis, established from the inner ring bore surface
Sia4) Circular axial run-out of inner ring face of assembled bearing with respect to datum, i.e. axis, established from the outer ring outside surface
 
   
  Radial bearings inner ring - tapered bore only
 
d1 Nominal bore diameter at the theoretical large end of a tapered bore
Δd1mp Deviation of a mid-range size (out of two-point sizes) of bore diameter at the theoretical large end from its nominal size
SL Taper slope, the difference between nominal diameters at the theoretical large end and small end of a tapered bore (d1 - d)
ΔSL Deviation of taper slope of a tapered inner ring bore from its nominal size
 
  Radial bearings outer ring
 
D Nominal outside diameter
ΔDmp Deviation of a mid-range size (out of two-point sizes) of outside diameter in any cross section from its nominal size
ΔDs Deviation of a two-point size of outside diameter from its nominal size
VDsp Range of two-point sizes of outside diameter in any cross section
VDmp Range of mid-range sizes (out of two-point sizes) of outside diameter obtained from any cross section
C Nominal outer ring width
ΔCs
Normal, 
Modified1)
  1. Symmetrical rings: Deviation of a two-point size of outer ring width from its nominal size
  2. Asymmetrical rings, upper limit: Deviation of a minimum circumscribed size of outer ring width, between two opposite lines, in any longitudinal section which includes the outer ring outside surface axis, from its nominal size
  3. Asymmetrical rings, lower limit: Deviation of a two-point size of outer ring width from its nominal size
VCs
  1. Symmetrical rings: Range of two-point sizes of outer ring width
  2. Asymmetrical rings: Range of minimum circumscribed sizes of outer ring width, between two opposite lines, obtained from any longitudinal section which includes the outer ring outside surface axis
Kea4) Circular radial run-out of outer ring outside surface of assembled bearing with respect to datum, i.e. axis, established from the inner ring bore surface
SD4) Perpendicularity of outer ring outside surface axis with respect to datum established from the outer ring face
Sea4) Circular axial run-out of outer ring face of assembled bearing with respect to datum, i.e. axis, established from the inner ring bore surface
 
  Chamfer limits
 
rs Single chamfer dimension
rs min Smallest single chamfer dimension of rs, r1, r2, r3, r4 …
r1, r3 Radial direction chamfer dimensions
r2, r4 Axial direction chamfer dimensions
 
  Tapered roller bearings
 
T Nominal assembled bearing width
ΔTs Deviation of minimum circumscribed size of assembled bearing width from its nominal size
T1 Nominal effective width of cone (inner ring, with roller and cage assembly) assembled with a master cup (outer ring)
T2 Nominal effective width of cup assembled with a master cone
ΔT1s Deviation of minimum circumscribed size of effective width (cone assembled with a master cup) from its nominal size
ΔT2s Deviation of minimum circumscribed size of effective width (cup assembled with a master cone) from its nominal size
 
  Thrust bearings shaft washer
 
d Nominal bore diameter of shaft washer, single direction bearing
Δds Deviation of a two-point size of shaft washer bore diameter from its nominal size
Δdmp Deviation of a mid-range size (out of two-point sizes) of shaft washer bore diameter in any cross section from its nominal size
Vdsp Range of two-point sizes of shaft washer bore diameter in any cross section
d2 Nominal bore diameter of central shaft washer, double direction bearing
Δd2mp Deviation of a mid-range size (out of two-point sizes) of central shaft washer bore diameter in any cross section from its nominal size
Vd2sp Range of two-point sizes of central shaft washer bore diameter in any cross section
Si
  1. Range of two-point sizes of thickness between shaft washer raceway and the back face, cylindrical roller thrust bearing
  2. Range of minimum spherical sizes between the raceway and the opposite back face of the shaft washer, obtained from any longitudinal section which includes the shaft washer bore axis, thrust ball bearing
 
  Thrust bearings housing washer
 
D Nominal outside diameter of housing washer
ΔDs Deviation of a two-point size of housing washer outside diameter from its nominal size
ΔDmp Deviation of a mid-range size (out of two-point sizes) of housing washer outside diameter in any cross section from its nominal size
VDsp Range of two-point sizes of housing washer outside diameter in any cross section
Se
  1. Range of two-point sizes of thickness between housing washer raceway and the back face, cylindrical roller thrust bearing
  2. Range of minimum spherical sizes between the raceway and the opposite back face of the housing washer, obtained from any longitudinal section which includes the housing washer outside surface axis, thrust ball bearing
 
  Thrust bearings assembled bearing height
 
T Nominal assembled bearing height, single direction thrust bearing (except spherical roller thrust bearing → T4)
ΔTs Deviation of minimum circumscribed size of assembled bearing height from its nominal size, single direction thrust bearing (except spherical roller thrust bearing → ΔT4s)
T1
  1. Nominal assembled bearing height, double direction thrust bearing
  2. Nominal assembled bearing height, single direction thrust bearing with a seat washer
ΔT1s
  1. Deviation of minimum circumscribed size of assembled bearing height from its nominal size, double direction thrust bearing
  2. Deviation of minimum circumscribed size of assembled bearing height from its nominal size, single direction thrust bearing with a seat washer
T32) Nominal assembled bearing height, double direction thrust bearing with seat washers
ΔT3s2) Deviation of minimum circumscribed size of assembled bearing height from its nominal size, double direction thrust bearing with seat washers
T43) Nominal assembled bearing height, spherical roller thrust bearing
ΔT4s3) Deviation of minimum circumscribed size of assembled bearing height from its nominal size, spherical roller thrust bearing
  • 1) Modified applies to inner rings and outer rings of bearings of matched bearing sets consisting of two or more bearings. Does not apply to universally matchable angular contact ball bearings.
  • 2) Not included in ISO 199.
  • 3) In ISO 199, the symbol T is used.
  • 4) Geometrical tolerances 

The bore and outside diameter variation tolerances tVdsp and tVDsp for metric radial bearings vary depending on the diameter series to which the bearing belongs. To determine the diameter series, refer to SKF bearing designation.

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