Thereare also differences in the root and crest of the threads. While NPTF thread crests sit within the same parameters as NPT standards, NPTF crests have a smaller range. mm. inch. mm. inch. inch. 5/8 - 18-10. 15.9. 0.63. 14.2. 0.56-6. 3/4 - 16 to and fully interchangeable with the SAE Code 61 flange fitting (5/8 is not in the SAE mm Nominal Pipe Size (Ø) 3/8" Pipe Outside Diameter (D) 0.675: 17.145: Pitch (TPI) (P) BSPT& BSPP Threads Dimensions. Thread size refers to the nominal bore of the pipe. Subtract approx. 1/4″ (6mm) from thread diameter measurement for nominal pipe size. Pitch is Threads Per Inch (TPI). 8 0.125. 114.30. 4.500. View our handy online thread size tables to help you find all the information you need about the valve or pipe threads you are working with. Our tables cover thread size, threads per inch, pitch and thread diameter. We have thread tables for both British Standard Pipe (BSP) and National Pipe Thread (NPT).
ThreadDiameter in . mm Pitch Page 3/8 UNF 0 .375 to 0 .363 9 .53 to 9 .22 24U 30 to 35 NPSM 0 .658 16 .71 18U 51 ISO 228/1 0 .656 16 .66 19W 36 to 43 Note: 1/2 and 3/4 in . ISO 7/1 and NPT threads can be difficult to identify because they are very close in design .
. 170 296 379 133 471 446 60 453

3 8 npt thread dimensions in mm