Categories
Fittings-Couplers-Valves
Stainless Steel, Brass, Acetel & Polysulfone:
Fittings - Adapters - Plugs - Caps - Nuts - Gaskets - Crosses - Tees - Reducers - Expanders - Elbows - Swivels - Couplings - Unions - Valves - Etc.
How to determine Pipe Thread Size
Pipe thread sizes do not refer to any physical dimensions. The outside diameter of each pipe fitting must be measured and compared to the table for size identification. For example: a 1/4" NPT has an outside dimension of 0.54". This is especially important when looking for Regulator fittings.
NPT Size Thread Diameter | Thread Diameter (O.D. of MPT or I.D. of FPT) |
---|---|
1/8" NPT | 0.405 |
1/4" NPT | 0.54 |
3/8" NPT | 0.675 |
1/2" NPT | 0.84 |
3/4" NPT | 1.05 |
1" NPT 1 | 1.315 |
1-1/4" NPT | 1.66 |
1-1/2" NPT | 1.9 |
2" NPT | 2.375 |
2-1/2" NPT | 2.875 |
3" NPT | 3.5 |
4" NPT | 4.5 |
ABOUT THREAD TYPES:
Pipe thread, Flare thread, Machine thread, etc ARE NOT COMPATIBLE. They will not screw onto/into each other.
Make sure the parts you choose are compatible, if needed.