Pipe design - metric vs NPT
Pipe design - metric vs NPT
(OP)
I'm about to get involved in doing piping design for a German customer. Am I correct in assuming that the DN nominal pipe sizes (e.g. 100 sch 40 is the same as 4" sch 40 NPT) are the same as we use in the US?
If that's true why are the pipe flanges different?
If that's true why are the pipe flanges different?





RE: Pipe design - metric vs NPT
The notes reflect that -
“NPS (Nominal Pipe Size) is a dimensionless designator that has been substituted in the customary units section for the previous term Inch Nominal Size.
” DN (Nominal Diameter) is a dimensionless designator used in the SI (metric) system to describe pipe size.