The terms “pipe” and “tube” are often used interchangeably, but there are several differences between them.
- Pipe is always cylindrical or round, but tubes can come in different profiles like square, rectangular and cylindrical.
- Pipe is measured using schedule and the inside diameter (I.D.) of material (2 inch sch. 40 pipe measures 2.375 inches O.D.) while tube is measured by outside diameter (O.D.) and wall thickness of material (2 inch tube measures 2.00 inches O.D.).
- Tube is often used in applications that require precise outside diameters.
- Because pipe is often used to carry fluids that must be contained, it has a pressure rating and schedule to indicate its strength.
- The wall thickness of tubes increase in standard increments. Since pipe thickness depends on the schedule, there is no fixed increment.
Click on the following links for more tube and pipe information.