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Disclaimer — Pipe Size Measurement Tolerances

Outside Diameter Tolerance + 0.015" / - 0.031"
Wall Thickness Tolerance + 20% / - 12.5%

IMPORTANT NOTE: Nominal pipe size material is an industrial product that has an internationally accepted set of tolerances (based on the ASTM specification) that allows for a wider range of "play" in the sizing of the material. From the table above, the ASTM A312 specification that encompasses all of our straight lengths of pipe size material allows for some variance in the Outside Diameter and Wall Thickness (Schedule).

Using 1-1/2" Schedule 10 material as an example, the OD can be as small as 1.869" or as large as 1.915" and still be within the tolerance of the material. For the wall thickness, the pipe can have a wall thickness as thin as 0.0953" and as thick as 0.1308" and still be within the tolerance of the material. Material that is on the "light" or "heavy" side of the tolerance is still considered to be 1-1/2" Schedule 10 material. Please consider these variations in material dimensions prior to ordering.

Please note that we do not under any circumstances offer a guaranteed Inside Diameter (ID) dimension and all ID dimensions are approximate only.