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December 4, 2019

Nominal Pipe Size & Pipe Schedules

NPS, or nominal pipe size, is the North American set of size standards for pipes that are used for temperatures and pressures of all ranges. The nominal pipe size identifies the size of the diameter of the pipe’s hole with a non-dimensional number. Using the NPS, a pipe is identified by its diameter and then with another non-dimensional number for the pipe’s wall thickness.