NPT - American Standard Pipe Thread/Taper Guide:
NPT is not a measured size, but rather an industry call out size.
The NPT call out designation is not the true thread diameter inside or out.
|
PROBE THREAD SIZE |
ACTUAL OUTSIDE DIAMETER |
| 1/8" NPT | 0.405" (Approx. 13/32") |
| 1/4" NPT | 0.540" (Approx. 1/2") |
| 3/8" NPT | 0.675" (Approx. 5/8") |
| 1/2" NPT | 0.840" (Approx. 7/8") |
AN Fitting Size Guide:
The AN numbers refer to the tubing OD in sixteenths of an inch.
|
AN SIZE |
MALE THREAD SIZE |
TUBE SIZE (NOMINAL OD) | HOSE ID |
| 4AN | 7/16"-20 | 1/4" | 0.22" |
| 6AN | 9/16"-18 | 3/8" | 0.34" |
| 8AN | 3/4"-16 | 1/2" | 0.44" |
| 10AN | 7/8"-14 | 5/8" | 0.56" |
| 12AN | 1 1/16"-12 | 3/4" | 0.69" |
