8. Tolerances and permissible values for tapered bores

Theoretical tapered bore Tapered bore with single plane mean bore diameter deviation

Table 4-14(1) Tapered ratio 1/12
Unit:m
Nominal bore diameter
d , mm		 dmp d1mp - dmp Vdp1) 2)
classes 0, 6 classes 5, 4 classes 0, 6 classes 5, 4 classes 0, 6

classes 5, 4
over up to upper lower upper lower upper lower upper lower max. max.
-
10
18		 10
18
30
+22
+27
+33		 0
0
0
+15
+18
+21		 0
0
0
+15
+18
+21		 0
0
0
+6
+8
+9		 0
0
0
9
11
13		 5
5
6
30
50
80		 50
80
120
+39
+46
+54		 0
0
0
+25
+30
+35		 0
0
0
+25
+30
+35		 0
0
0
+11
+13
+15		 0
0
0
16
19
22		 8
9
10
120
180
250		 180
250
315
+63
+72
+81		 0
0
0
+40
+46
+52		 0
0
0
+40
+46
+52		 0
0
0
+18
+20
+23		 0
0
0
40
46
52

13
15
18
315
400
500		 400
500
630
+89
+97
+110		 0
0
0
+57
+63
-		 0
0
-
+57
+63
+70		 0
0
0
+25
+27
-		 0
0
-
57
63
70		 23
25
-
630
800
1000
1250		 800
1000
1250
1600
+125
+140
+165
+195		 0
0
0
0
-
-
-
-		 -
-
-
-
+80
+90
+105
+125		 0
0
0
0
-
-
-
-		 -
-
-
-
-
-
-
-		 -
-
-
-

Table 4-14(2) Tapered ratio 1/30 (class 0)
Unit:m
Nominal bore diameter d , mm dmp d1mp - dmp Vdp1) 2)
over up to upper lower upper lower max.
50
80
120		 80
120
180
+15
+20
+25		 0
0
0
+30
+35
+40		 0
0
0
19
22
40
180
250
315		 250
315
400
+30
+35
+40		 0
0
0
+46
+52
+57		 0
0
0
46
52
57
400
500		 500
630
+45
+50		 0
0
+63
+70		 0
0
63
70
[Notes] 1) These shall be applied to all radial planes with tapered bore.
2) Not applied to bearings of diameter series 7, 8.
 
[Remarks] 1. Symbols of dimension d1 : reference diameter at theoretical large end of tapered bore d1=d+(1/12)B
dmp : single plane mean bore diameter deviation at theoretical small end of tapered bore
d1mp : single plane mean bore diameter deviation at theoretical large end of tapered bore
Vdp : bore diameter variation in a single radial plane
B : nominal inner ring width
: 1/2 of nominal tapered angle of tapered bore
(tapered ratio 1/12) (tapered ratio 1/30)
=223'9.4" =057'17.4"
    =2.38594     =0.95484
    =0.041643rad     =0.016665rad
2.
Values in italics are prescribed in Koyo standards.