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NPS
Nominal Pipe Size — a North American standard for designating pipe diameter. NPS is a dimensionless designator that corresponds approximately to the inside diameter in inches for sizes up to NPS 12.
What is NPS?
NPS (Nominal Pipe Size) is a North American set of standard sizes used to designate pipe diameter. It is loosely related to the inside diameter but is a dimensionless number. Each NPS corresponds to a specific outside diameter (OD), while the wall thickness varies by schedule number.
NPS to OD Conversion
- NPS 1/2" = 21.3mm OD
- NPS 1" = 33.4mm OD
- NPS 2" = 60.3mm OD
- NPS 4" = 114.3mm OD
- NPS 6" = 168.3mm OD
- NPS 8" = 219.1mm OD
- NPS 10" = 273.1mm OD