Pipes and what should I need to know

[v***@yahoo.com]

Hello people,
I hope this is the right place for my question.
I want to learn few facts about pipes and diameters.
First if pipe diameter is DN 100, I know that DN stands for Diameter
Nominal
but I'm not sure if the units is in mm. If nothing more is there I
assume that DN 100 means diameter of 100 mm.
Also, I'm not sure if that means inner diameter or outside diameter?
I wrote somewhere that when talking about diameter of pipes there is
ALWAYS talk about inner diameter.
Can you confirm this?

Thank you very much

[Jack]

http://www.nibs.org/MetricNews/2qtr99.PDF#search='pipe%20size%20nomenclature'

Post by v***@yahoo.com
Hello people,
I hope this is the right place for my question.
I want to learn few facts about pipes and diameters.
First if pipe diameter is DN 100, I know that DN stands for Diameter
Nominal
but I'm not sure if the units is in mm. If nothing more is there I
assume that DN 100 means diameter of 100 mm.
Also, I'm not sure if that means inner diameter or outside diameter?
I wrote somewhere that when talking about diameter of pipes there is
ALWAYS talk about inner diameter.
Can you confirm this?
Thank you very much