Custom computers and motorcycles

Tube v Pipe


†††††††† There are a lot of people that either donít know or are misinformed. There are some differences in tubing and pipe that should be taken into consideration before a project is started.

†††††††††††† First letís look at pipe. Pipe can be found at the local hardware store, it can be found in all kinds of lengths and it is fairly cheap. It has a protective black coating and is usually pre threaded on both ends. Commonly known as ďblack pipeĒ or ďblack ironĒ, this pipe is easy to work with and bend. As long as you donít weld it or use it in a structural application it will do anything you want. Black iron is called that for a reason, it has a high iron content and if welded it must be done in a very controlled process. If you take pipe, and attempt to weld it everything will weld just fine. The bead will look good and there will be good penetration. The problem comes in because the high iron content causes the pipe metal to crystallize and spider web. It you put stress on the joint it will fail right beside the weld and the metal will look crystalline. On top of that it is sized by the I.D. Half inch pipe ends up being nearly 3/4 on the O.D. Wall thickness also varies heavily through the length of pipe. Basically it boils down to, leave black pipe to itís job it was designed for, carrying water.†

†††††††††††† Now letís look at tubing. It is normally made of cold rolled steel, not iron, and comes in various sizes. Tubing is sized by O.D. so 1/2 tube is 1/2. wall thickness has tighter tolerances and is designed to be used in structural applications. It is easily welded and if left to cool naturally it is structurally sound. I think there is nothing else to say.