The difference between DOM tube and Chromoly Tube

We encounter numerous structural steel pipes in our daily lives. These include car roll cages, chassis supports, and bicycle frames. The two most common types of structural steel pipe are DOM (Dom) and Chromoly (Chromoly) pipes. To understand their differences, you first need to understand what they are.

DOM pipe

DOM stands for Drawn Over Mandrel Steel Tube. It is a welded pipe drawn over a mandrel. Yes, you heard it right. DOM is a welded pipe without a weld seam. The DOM pipe process involves further processing cold-bent steel pipe to smooth the inner surface of the weld and improve its mechanical properties. This is achieved by annealing (heating) the pipe to soften it so that it can be pulled through a tapered steel mandrel (i.e., "pulling the pipe over the mandrel").

Chromoly Tube

Chromoly tube is a type of tubing made from a chromium-molybdenum alloy. It's a higher-strength seamless alloy steel pipe and is commonly used in high-performance bicycle frames, racing cars, and even in the structural steel of space shuttles, thanks to its high strength, corrosion resistance, and excellent weldability.

The difference between them lies in their material. DOM tubes are generally made from low-carbon steel, while Chromoly tubes are alloy steel tubes. Their performance characteristics also differ. DOM is known for its high dimensional accuracy and weld strength, making it suitable for precision machining, such as in ordinary automobiles and bicycles. Chromoly tubes, on the other hand, can withstand more extreme conditions and are widely used in aerospace, racing chassis, and other applications requiring high strength.