Steel 101: Difference
Between Pipe and Tube
For any individual who
is foreign to manufacturing and engineering, the terms ‘pipe’ and ‘tube’ might initially
come across as identical. And in many ways, pipes and tubes are similar. However,
with a little more familiarity with the characteristics and properties of the
two, there are several ways to differentiate between pipe and tube.
PIPE
According to the
National Association of Steel Pipe Distributors (NASPD) Pipe is a cylindrical
conductor, manufactured from steel, with a hollow inside.
When trying to determine measurements and sizes for steel
pipe, it is important to remember that pipe size follows an industry standard,
so the sizing is always going to be identical, regardless of the steel grade. There are four dimensions relevant to the measurement of
steel pipe: Inside Diameter (ID), Outside Diameter (OD), Wall Thickness and
Length.
- · Inside Diameter- Is the distance of a straight line passing through the center of the pipe from one inside purpose of the pipe to its opposite inside surface.
- · Outside Diameter- Is the distance of a straight line passing through the center of the pipe from one outside rim of the pipe to its opposite outside rim.
- · Wall Thickness- The thickness of the pipe’s wall, the distance of a straight line between the outer surface and the inner surface at a point where the straight line is perpendicular to both surfaces.
- · Length- How long the pipe is from end to end.
The American National
Standards Institute (ANSI) established that steel pipe is measured by Nominal
Pipe Size (NPS). NPS is specified by two designations, the diameter of the pipe
based in inches, and a schedule for wall thickness. NPS
of 1/8 of an inch through 12-inch NPS are identified by their nominal inside
diameters. On the other hand, pipe that is larger than NPS 12” are identified
by their nominal outside diameters and are considered Large OD pipe.
TUBING
On the other hand, there’s
tube. Tubing is a hollow shaped product with a relatively uniform wall
thickness. Tube can be manufactured rounded, square, rectangular or octagon to
name a few. Tube can also be manufactured to specified requirements for
dimensions, chemical analysis, mechanical properties and countless other mechanisms.
Some of these mechanisms
include tube being manufactured into lengths for various applications,
including machinery and gates, panels, corrals, fences, feedlots, structural
applications and various other projects. Tube can either be hot rolled steel or cold rolled
steel.
