| CLASS
OF FIT |
|
Plug
gauges
(Internal)
|
Ring
gauges
(External)
|
Application
|
|
1B
|
1A
|
Where
quick assembly is needed even when threads are
dirty / damaged wide tolerances for male and female
threads.
|
|
2B
|
2A
|
Corresponds
to medium fit and used for general applications
which requires free assembly.
|
|
3B
|
3A
|
Where
closer fit is required.
|
|
| DIAMETER
– PITCH COMBINATION |
| Diameter
– TPI combination not covered in this table as well
as for all diameters above 6" use "UNS" series irrespective
of TPI. |
|
Dia
Inch
|
Dia
MM
|
UNC
|
UNF
|
UNEF
|
UN
|
| No.
0 |
1.524
|
-
|
80
|
-
|
-
|
| No.
1 |
1.8542
|
64
|
72
|
-
|
-
|
| No.
2 |
2.1844
|
56
|
64
|
-
|
-
|
| No.
3 |
2.5146
|
48
|
56
|
-
|
-
|
| No.
4 |
2.8448
|
40
|
48
|
-
|
-
|
| No.
5 |
3.175
|
40
|
44
|
-
|
-
|
| No.
6 |
3.5052
|
32
|
40
|
-
|
-
|
| No.
8 |
4.1656
|
32
|
36
|
-
|
-
|
| No.
10 |
4.826
|
24
|
32
|
-
|
-
|
| No.
12 |
5.4864
|
24
|
28
|
32
|
-
|
| ¼"
|
6.350
|
20
|
28
|
32
|
-
|
| 5/16"
|
7.9375
|
18
|
24
|
32
|
20,28
|
| 3/8"
|
9.525
|
16
|
24
|
32
|
20,28
|
| 7/16"
|
11.1125
|
14
|
20
|
28
|
16,32
|
| ½"
|
12.700
|
13
|
20
|
28
|
16,32
|
| 9/16"
|
14.2875
|
12
|
18
|
24
|
16,20,28,32
|
| 5/8"
|
15.8750
|
11
|
18
|
24
|
12,16,20,28,32
|
| 11/16"
|
17.4625
|
|
|
24
|
12,16,20,28,32
|
| ¾"
|
19.050
|
10
|
16
|
20
|
12,28,32
|
| 13/16"
|
20.6375
|
|
|
20
|
12,16,28,32
|
| 7/8"
|
22.225
|
9
|
14
|
20
|
12,16,28,32
|
| 15/16"
|
23.8125
|
|
|
20
|
12,16,28,32
|
|
Dia
Inch
|
Dia
MM
|
UNC
|
UNF
|
UNEF
|
UN
|
| 1"
|
25.400
|
8
|
12
|
20
|
16,28,32
|
| 1.1/16"
|
26.9875
|
|
|
18
|
8,12,16,20,28
|
| 1.1/8"
|
28.575
|
7
|
12
|
18
|
8,16,20,28
|
| 1.3/16"
|
30.1625
|
|
|
18
|
8,12,16,20,28
|
| 1.1/4"
|
31.750
|
7
|
12
|
18
|
8,16,20,28
|
| 1.5/16"
|
33.3375
|
|
|
18
|
8,12,16,20,28
|
| 1.3/8"
|
34.925
|
6
|
12
|
18
|
8,16,20,28
|
| 1.7/16"
|
36.5125
|
|
|
18
|
6,8,12,16,20,28
|
| 1.1/2"
|
38.100
|
6
|
12
|
18
|
8,16,20,28
|
| 1.9/16"
|
39.6875
|
|
|
18
|
6,8,12,16,20
|
| 1.5/8"
|
41.275
|
|
|
18
|
6,8,12,16,20
|
| 1.11/16 |
42.8625
|
|
|
18
|
6,8,12,16,20
|
| 1.3/4
|
44.450
|
5
|
|
|
6,8,12,16,20
|
| 1.13/16
|
46.0375
|
|
|
|
6,8,12,16,20
|
| 1.7/8
|
47.625
|
|
|
|
6,8,12,16,20
|
| 1.15/16
|
49.2125
|
|
|
|
6,8,12,16,20
|
| 2
|
50.800
|
4.5
|
|
|
6,8,12,16,20
|
| 2.1/8" |
53.975
|
-
|
-
|
-
|
6,8,12,16,20
|
| 2.1/4" |
57.150
|
4.5
|
-
|
-
|
6,8,12,16,20
|
| 2.3/8" |
60.325
|
-
|
-
|
-
|
6,8,12,16,20
|
| 2.1/2" |
63.500
|
4
|
-
|
-
|
6,8,12,16,20
|
| 2.5/8" |
66.675
|
-
|
-
|
-
|
4,6,8,12,16,20
|
|
Dia
Inch
|
Dia
MM
|
UNC
|
UNF
|
UNEF
|
UN
|
|
|
| DIAMETER
– PITCH COMBINATION |
|
Dia
Inch
|
Dia
MM
|
UNC
|
UNF
|
UNEF
|
UN
|
| 2.3/4" |
69.850
|
4
|
-
|
-
|
6,8,12,16,20
|
| 2.7/8" |
73.025
|
-
|
-
|
-
|
4,6,8,12,16,20
|
| 3" |
76.200
|
4
|
-
|
-
|
6,8,12,16,20
|
| 3.1/8" |
79.375
|
-
|
-
|
-
|
4,6,8,12,16
|
| 3.1/4" |
82.550
|
4
|
-
|
-
|
6,8,12,16
|
| 3.3/8" |
85.725
|
-
|
-
|
-
|
4,6,8,12,16
|
| 3.1/2" |
88.900
|
4
|
-
|
-
|
6,8,12,16
|
| 3.5/8" |
92.075
|
-
|
-
|
-
|
4,6,8,12,16
|
| 3.3/4" |
95.250
|
4
|
-
|
-
|
6,8,12,16
|
| 3.7/8" |
98.425
|
-
|
-
|
-
|
4,6,8,12,16
|
| 4" |
101.60
|
4
|
-
|
-
|
6,8,12,16
|
| 4.1/8" |
104.775
|
-
|
-
|
-
|
4,6,8,12,16
|
| 4.1/4" |
104.950
|
-
|
-
|
-
|
4,6,8,12,16
|
| 4.3/8" |
111.125
|
-
|
-
|
-
|
4,6,8,12,16
|
| 4.1/2" |
114.30
|
-
|
-
|
-
|
4,6,8,12,16
|
| 4.5/8" |
117.475
|
-
|
-
|
-
|
4,6,8,12,16
|
| 4.3/4" |
120.650
|
-
|
-
|
-
|
4,6,8,12,16
|
| 4.7/8" |
123.825
|
-
|
-
|
-
|
4,6,8,12,16
|
| 5" |
127.000
|
-
|
-
|
-
|
4,6,8,12,16
|
| 5.1/8" |
130.175
|
-
|
-
|
-
|
4,6,8,12,16
|
| 5.1/4" |
133.350
|
-
|
-
|
-
|
4,6,8,12,16
|
| 5.3/8" |
136.525
|
-
|
-
|
-
|
4,6,8,12,16
|
| 5.1/2" |
139.700
|
-
|
-
|
-
|
4,6,8,12,16
|
| 5.5/8" |
142.875
|
-
|
-
|
-
|
4,6,8,12,16
|
| 5.3/4" |
146.050
|
-
|
-
|
-
|
4,6,8,12,16
|
| 5.7/8" |
149.225
|
-
|
-
|
-
|
| | | |
