1/2-14 NPT thread: 21.34 mm × 14 TPI
Threads › 1/2-14 NPT
1/2-14 NPT is an NPT taper thread: 21.34 mm pipe OD, 14 TPI (1.814 mm pitch), 60° form. Tap drill 18.3 mm. Taper thread: the Ø changes along the length, measure near the start.
| Standard | NPT taper |
|---|---|
| Pipe OD | 21.336 mm (0.84″) |
| Pitch | 14 TPI (1.814 mm) |
| Thread angle | 60° |
| Tap drill | 18.3 mm |
Open 1/2-14 NPT in BenchsmithAdd to order list
Measure it
Bolt: Measure across the crests of the bolt with the caliper jaws. Worn bolts read 0.1 to 0.3 under.
Nut or tapped hole: Measure across the tops of the threads inside the nut or hole with the inside jaws. That is the minor Ø. Worn or oversize holes read a little over.
Close in size, won't mate
- G1/2Ø20.96 mm, 14 TPI
- R1/2Ø20.96 mm, 14 TPI
- M22Ø22 mm, 2.5 mm pitch
- M22×1.5Ø22 mm, 1.5 mm pitch
- Tr22×5Ø22 mm, 5 mm pitch
- 7/8-9 UNCØ22.23 mm, 9 TPI
One size up or down
- 3/8-18 NPTØ17.15 mm (down)
- 3/4-14 NPTØ26.67 mm (up)
Got a bolt and no idea what it is? Measure the outside Ø and type it into Benchsmith → Find → Thread.