Pipe
Taper and Straight Thread Dimensions
National
Pipe Taper and Straight Thread Dimensions
NPT Size |
Threads
Per Inch |
Dim "A"
(In.) |
Dim "B"
(In.) |
1/16 |
27 |
.312 |
.261 |
1/8 |
27 |
.405 |
.264 |
1/4 |
18 |
.540 |
.402 |
3/8 |
18 |
.675 |
.408 |
1/2 |
14 |
.840 |
.534 |
3/4 |
14 |
1.050 |
.546 |
1 |
111/2 |
1.315 |
.683 |
11/4 |
111/2 |
1.660 |
.707 |
Nominal
Thread
Size
|
Threads
Per Inch
|
Major
Diameter
|
W
|
H
|
L
|
Coarse
(UNC) |
Fine
(UNF)
|
0 |
- |
80 |
0.0600 |
|
|
|
1 |
64 |
72 |
0.0730 |
|
|
|
2 |
56 |
64 |
0.0860 |
|
|
|
3 |
48 |
56 |
0.0990 |
|
|
|
4 |
40 |
48 |
0.1221 |
|
|
|
5 |
40 |
44 |
0.1250 |
|
|
|
6 |
32 |
40 |
0.1380 |
|
|
|
8 |
32 |
36 |
0.1640 |
|
|
|
10 |
24 |
32 |
0.1900 |
|
|
|
12 |
24 |
28 |
0.2160 |
|
|
|
1/4 |
20 |
28 |
0.2500 |
7/16 |
11/64 |
0.750 |
5/16 |
18 |
24 |
0.3125 |
1/2 |
7/32 |
0.875 |
3/8 |
16 |
24 |
0.3750 |
9/16 |
1/4 |
1.000 |
7/16 |
14 |
20 |
0.4375 |
5/8 |
19/64 |
1.125 |
1/2 |
13 |
20 |
0.5000 |
3/4 |
11/32 |
1.250 |
9/16 |
12 |
18 |
0.5625 |
13/16 |
3/8 |
1.375 |
5/8 |
11 |
18 |
0.6250 |
15/16 |
27/64 |
1.500 |
3/4 |
10 |
16 |
0.7500 |
11/8 |
1/2 |
1.750 |
7/8 |
9 |
14 |
0.8750 |
15/16 |
37/64 |
2.000 |
1 |
8 |
12 |
1.0000 |
11/2 |
43/64 |
2.250 |
11/8 |
7 |
12 |
1.1250 |
111/16 |
3/4 |
2.500 |
11/4 |
7 |
12 |
1.2500 |
17/8 |
27/32 |
2.750 |
13/8 |
6 |
12 |
1.3750 |
21/16 |
29/32 |
3.000 |
11/2 |
6 |
12 |
1.5000 |
21/4 |
1 |
3.250 |
|