Understanding Steel Pipe Dimensions
Steel pipe dimensions are defined by Nominal Pipe Size (NPS), outside diameter (OD) and wall thickness determined by pipe schedule. Understanding these parameters is essential for radiographic interpretation. This reference guide provides standard steel pipe size data for industrial and inspection applications.
Nominal Pipe Size (NPS)
NPS is a standard pipe size designation. For NPS 1/8 to 12, it does not equal the actual outside diameter.
Outside Diameter (OD)
OD is the fixed external diameter of the pipe. For a given NPS, the OD remains constant regardless of schedule.
Pipe Schedule (SCH)
Schedule defines wall thickness. Higher schedule numbers indicate thicker pipe walls and reduced internal diameter.
Wall Thickness
Wall thickness determines pressure rating and corrosion allowance. Accurate values are critical for inspection and wall loss calculations.
