Pipe with threading is used in plumbing as well as pressurized air and gas applications. Pipe taps are the cutting tool that enables a machinist or tradesman to form those threads. Pipe joints are a sealed joint, so the threads are conical and not cylindrical. Pipe taps cut the threads on the inside of a pipe in this conical design. Some types pipe taps cut threads that need joint compound teflon tape to make the seal waterproof.
Other types of pipe taps created threads that form a watertight fit.
British Standard Pipe Taps cut threads to the BSP (British Standard Pipe) standard. These pipe taps cut parallel threads in sizes of 1/8, 1/4, 3/8, 1/2, 5/8, 3/4, and a full inch or more.
British Standard Pipe Tapered Pipe Taps cut threads to the BSP (British Standard Pipe) standard. These pipe taps cut tapered threads in sizes of 1/8, 1/4, 3/8, 1/2, 5/8, 3/4, and a full inch or more.
In the US and Canada, pipe taps are used to cut threads to the NPT (National Pipe Tapered) standard. These pipe taps range from 1/16 inch through much larger pipe tap sizes.
BSPT pipe taps and NPT pipe tapes are not mechanically interchangeable.
| PIPE TAPS SIZE |
*NPT PIPE TAPS SIZES |
*NPFT PIPE TAPS SIZES |
STRAIGHT PIPE TAPS SIZES |
PIPE TAPS
DRILL |
PIPE TAPS
DECIMAL EQUIV. |
PIPE TAPS
DRILL |
PIPE TAPS
DECIMAL EQUIV. |
PIPE TAPS
DRILL |
PIPE TAPS
DECIMAL EQUIV. |
| 1/16" Pipe Taps |
D |
0.246 |
D |
0.246 |
1/4 |
0.25 |
| 1/8" Pipe Taps |
Q |
0.332 |
R |
0.339 |
11/32 |
0.3438 |
| 1/4" Pipe Taps |
7/16 |
0.4375 |
7/16 |
0.4375 |
7/16 |
0.4375 |
| 3/8" Pipe Taps |
9/16 |
0.5625 |
37/64 |
0.5781 |
37/64 |
0.5781 |
| 1/2" Pipe Taps |
45/64 |
0.7031 |
45/64 |
0.7031 |
23/32 |
0.7188 |
| 3/4" Pipe Taps |
29/32 |
0.9062 |
59/64 |
0.9219 |
59/64 |
0.9219 |
| 1" Pipe Taps |
1 9/64 |
1.1406 |
1 5/32 |
1.1562 |
1 5/32 |
1.1562 |
| 1" 1/4 Pipe Taps |
1 31/64 |
1.4844 |
1 1/2 |
1.5 |
1 1/2 |
1.5 |
| 1" 1/2 Pipe Taps |
1 47/64 |
1.7344 |
1 47/64 |
1.7344 |
1 3/4 |
1.75 |
| 2" Pipe Taps |
2 13/64 |
2.2031 |
2 7/32 |
2.2188 |
2 7/32 |
2.2188 |
| 2" 1/2 Pipe Taps |
2 5/8 |
2.625 |
2 41/64 |
2.6406 |
2 21/32 |
2.6562 |
| 3" Pipe Taps |
|
|
3 17/64 |
3.2656 |
|
|
* Pipe taps - sizes for tapping without reaming.