Metal Tubing Glossary
In-depth metal terms, phrases, abbreviations, and acronyms with their meanings and definitions.
4130
4130 - Metal grade of Chromium Molybdenum. 4130 Chrome-Moly is comprised of (HSLA) high-strength low alloy steel. This combination of alloys offers higher strength to weight ratios. Therefore, designers and engineers prefer its qualities in applications where thin wall and lighter weight tubing is required.
ASTM
American Society for Testing and Materials. An international standards organization which produces materials and industry-wide standards for various products.
C1020
One of the most common carbon steel grade. C1020 is a low tensile carbon steel with excellent machinability. Commonly used for DOM processed tubing. Similar to C1026, both are iron alloys and have close composition.
C1026
C1026 is very similar to C1020. They are both low-tensile carbon iron. And, both are primarily for manufacturing DOM tubing.
CREW
Cold Rolled Steel is room temperature coil steel that has been rolled into tube form. The seam that completes the tube is joined by electric resistance welding (ERW). CREW is larger tubing that is used during the DOM process.
DOM
Drawn Over Mandrel is the process of which steel tube is pulled through a die in order to reduce its size.
ERW
Electric Resistance Welded pipe or tubing. ERW is used broadly in engineered applications as well as less tolerance uses like fencing, and tents. It is also used as a blank during the DOM tubing process.
Hollow
Hollow is a hollow metal profile. Essentially, it is the blank tube that is used prior to cold drawing. For example, in the case of DOM tubing, it is typically a larger CREW (Cold Rolled steel) blank tube. Next, the tube is pulled through a die.
LPG
LPG is an acronym for Liquid Petroleum Gas. A178A Boiler tube if frequently used for manufacturing LPG cylinders.
Mandrel
In the DOM process, a hardened steel rod (Mandrel) is inserted into the bore of the tube. It's this mandrel that is used to maintain and finish the inside surface of the tube.
Pointing
Pointing is literally squeezing one end of a tube length so that can be grabbed by jaws on a trolley which draws the tube through a die (DOM). There several pointing methods: squeeze pointing, push pointing, and rotary pointing.
Reeling
Specific to Rod Drawing, Reeling is a secondary operation that expands the diameter so that the mandrel can be extracted.
SRA
Stress Relieved Annealing. Heating metals to a predetermined temperature, then cooling at room temperature. Annealing relieves stresses that occurs when rolled, machines, or otherwise formed.