Tube and pipe are dimensioned differently and therefore require different die sets. Tubing is sized according to it's outside diameter (OD) and pipe is sized by it's nominal bore or inside dimension. However the actual outside diameter of the pipe is used to determine the die set size.
Some points to note when selecting tube or pipe for your project:
-Tube generally needs to be purchased from a specialty materials supplier.
-Pipe can be purchased from a general steel supplier.
-Tube is more expensive than pipe.
-Pipe is more economical to use for things like farm gates and 4wd rock sliders.
-Tube is used for aviation and sanctioned motorsport applications.
-Tube is stronger than pipe.
-Tube has different material grades available and many different wall gauges.
-Pipe comes in extra light , light , medium and heavy walls.
-Pipe has a seam inside and usually has a black or gal coating on the outside.
