Standard Pipe Schedule or Pipes Sizes as according to ANSI / ASME B36.10M and API 5L .
ANSI - American National Standards Institute
ASME - American Society of Mechanical Engineers
API = American Petroleum Institute
ASME/ANSI B 36.10 Welded Steel Pipe and Seamless Wrought Steel Pipe
ASME/ANSI B36.19 Stainless Steel Pipe
Nominal Wall Thickness (Inch) Weight per Foot (lb.)