ASME B18.2.2 - Table 13 - Coupling Nuts
| Nominal Size |
Thread Diameter |
Across Flat | Across Corners | Length | |||||
|---|---|---|---|---|---|---|---|---|---|
| d | s | e | h | ||||||
| Basic | Min | Max | Min | Max | Basic | Min | Max | ||
| #6 | 0.138 | 5/16 | 0.302 | 0.312 | 0.344 | 0.361 | 1/2 | 0.470 | 0.510 |
| #8 | 0.164 | 5/16 | 0.302 | 0.312 | 0.344 | 0.361 | 5/8 | 0.595 | 0.645 |
| #10 | 0.190 | 5/16 | 0.302 | 0.312 | 0.344 | 0.361 | 3/4 | 0.711 | 0.760 |
| 1/4 | 0.250 | 7/16 | 0.428 | 0.438 | 0.487 | 0.505 | 1 3/4 | 1.690 | 1.760 |
| 5/16 | 0.313 | 1/2 | 0.489 | 0.500 | 0.557 | 0.577 | 1 3/4 | 1.690 | 1.760 |
| 3/8 | 0.375 | 9/16 | 0.551 | 0.563 | 0.628 | 0.650 | 1 3/4 | 1.690 | 1.760 |
| 7/16 | 0.438 | 5/8 | 0.607 | 0.625 | 0.692 | 0.722 | 1 3/4 | 1.690 | 1.760 |
| 1/2 | 0.500 | 11/16 | 0.663 | 0.688 | 0.756 | 0.794 | 1 3/4 | 1.690 | 1.760 |
| 9/16 | 0.563 | 13/16 | 0.782 | 0.813 | 0.891 | 0.939 | 2 1/8 | 2.067 | 2.135 |
| 5/8 | 0.625 | 13/16 | 0.782 | 0.813 | 0.891 | 0.939 | 2 1/8 | 2.067 | 2.135 |
| 3/4 | 0.750 | 1 | 0.963 | 1.000 | 1.097 | 1.155 | 2 1/4 | 2.190 | 2.260 |
| 7/8 | 0.875 | 1 1/4 | 1.212 | 1.250 | 1.382 | 1.443 | 2 1/2 | 2.440 | 2.510 |
| 1 | 1.000 | 1 3/8 | 1.325 | 1.375 | 1.511 | 1.588 | 2 3/4 | 2.690 | 2.760 |
| 1 1/8 | 1.125 | 1 1/2 | 1.450 | 1.500 | 1.653 | 1.732 | 3 | 2.940 | 3.010 |
| 1 1/4 | 1.250 | 1 5/8 | 1.575 | 1.625 | 1.825 | 1.876 | 3 | 2.940 | 3.010 |
| 1 1/2 | 1.500 | 2 | 1.950 | 2.000 | 2.275 | 2.309 | 3 1/2 | 3.440 | 3.510 |
| 1 5/8 | 1.625 | 2 9/16 | 2.481 | 2.563 | 2.828 | 2.959 | 4 7/8 | 4.830 | 4.910 |
| 1 3/4 | 1.750 | 2 3/4 | 2.662 | 2.750 | 3.035 | 3.175 | 5 1/4 | 5.210 | 5.290 |
| 1 7/8 | 1.875 | 2 15/16 | 2.844 | 2.938 | 3.242 | 3.392 | 5 5/8 | 5.580 | 5.670 |
| 2 | 2.000 | 3 1/8 | 3.025 | 3.125 | 3.448 | 3.608 | 6 | 5.950 | 6.040 |
| 2 1/4 | 2.250 | 3 1/2 | 3.388 | 3.500 | 3.862 | 4.041 | 6 3/4 | 6.700 | 6.800 |
Nuts are typically made without the viewport hole, unless specified by you.
The viewport is desirable in those applications where it is desirable to have assurance that parts are engaged at approximately one half of nut thickness.
This viewport is located at mid-nut thickness and typically has a diameter of between 0.2 and 0.4 times the nominal nut size for sizes 2.1/2" and smaller.