Pipe designation in NB & DN

[vrl3]

Dear expert,

Kindly furnish the correct terminology of Pipe designations in NB DN and their references to ID and OD of pipes. Is there any rules for these designations

Regards

vrl3

 

[stanier]

Both NB and DN refer to an arbitary nominal size of pipe that is loosely related to the inside and outside diameter of the material. It varies depending upon whther the sizes are Imperial or metric (soft conversions), the material and the particular standard. ANSI B36.10 defines the sizes for American carbon steel in Imperial sizes but there are a miriad of ISO, JIS, Australian and other countries standards that cover ABS, PP, PE, FRP, PVC-U, PVC-O, PVC-M, Copper, ductile iron etc that have differing bores and outside diameters. You can look some sizes up on the net but you are better off referring to the pipe standard of manufacture of materials for details of ID and OD and the various tolerances on wall thickness, out of roundness, ovality, surface defects etc.