Thread Dimensions
Nominal Dimensions of Standard Threads
ODM - Outside Diameter of the Male
IDF - Inside Diameter of the Female
TPI - Threads Per Inch
| Size | Pipe O.D. | Tapered Threads | Straight Threads | ||||||||||||
| NPT | BSPTr | NPSH | NPSM | NST (NH) | BSPP | ||||||||||
| TPI | TPI | TPI | ODM (max) | IDF (min) | TPI | ODM (max) | IDF (min) | TPI | ODM (max) | IDF (min) | TPI | ODM (max) | IDF (min) | ||
| 1/8" | .405 | 27 | 28 | 27 | 0.397 | 0.358 | 0.383 | 0.337 | |||||||
| 1/4" | .504 | 18 | 19 | 18 | 0.526 | 0.468 | 0.516 | 0.450 | |||||||
| 3/8" | .675 | 18 | 19 | 18 | 0.662 | 0.603 | 0.656 | 0.588 | |||||||
| 1/2" | .840 | 14 | 14 | 14 | 0.8248 | 0.7395 | 14 | 0.823 | 0.747 | 0.825 | 0.733 | ||||
| 3/4" | 1.050 | 14 | 14 | 14 | 1.0353 | 0.9500 | 14 | 1.034 | 0.958 | 8 | 1.375 | 1.2246 | 1.041 | 0.950 | |
| 1" | 1.315 | 11.5 | 11 | 11.5 | 1.2951 | 1.1921 | 11.5 | 1.293 | 1.201 | 8 | 1.375 | 1.2246 | 11 | 1.309 | 1.193 |
| 1-1/4" | 1.660 | 11.5 | 11 | 11.5 | 1.6399 | 1.5369 | 11.5 | 1.638 | 1.546 | 11 | 1.650 | 1.534 | |||
| 1-1/2" | 1.900 | 11.5 | 11 | 11.5 | 1.8788 | 1.7758 | 11.5 | 1.877 | 1.785 | 9 | 1.990 | 1.8577 | 1.882 | 1.766 | |
| 2" | 2.375 | 11.5 | 11 | 11.5 | 2.3528 | 2.2498 | 11.5 | 2.351 | 2.259 | 11 | 2.347 | 2.231 | |||
| 2-1/2" | 2.875 | 8 | 11 | 8 | 2.8434 | 2.6930 | 8 | 2.841 | 2.708 | 7.5 | 3.068 | 2.9104 | 11 | 2.960 | 2.844 |
| 3" | 3.500 | 8 | 11 | 8 | 3.467 | 3.334 | 6 | 3.623 | 3.5306 | 11 | 3.460 | 3.344 | |||
| 4" | 4.500 | 8 | 11 | 8 | 4.466 | 4.333 | 4 | 5.010 | 4.7111 | 4.450 | 4.334 | ||||
| 4-1/2" | 4 | 5.760 | 5.4611 | 11 | |||||||||||
| 5" | 5.563 | 8 | 11 | 8 | 5.528 | 5.395 | 4 | 6.260 | 5.9602 | 11 | 5.450 | 5.359 | |||
| 6" | 6.625 | 8 | 11 | 8 | 6.585 | 6.452 | 4 | 7.025 | 6.7252 | 6.450 | 6.359 | ||||
| 8" | 8.625 | 8 | |||||||||||||
| 10" | 10.750 | 8 | |||||||||||||
| 12" | 12.750 | 8 | |||||||||||||
GHT (3/4") -- 1.0625 ODM, 11-1/2 TPI
Note: Female NPT (Tapered Pipe) thread is not available on hose swivelnuts.