Structural Hollow Sections

Two specific categories for processing structural hollow sections may be distinguished. Firstly the seamless process in which a hole is formed through a heated solid bar. The products performed by a seamless process will be covered on an extra page.

Secondly the welded process in which a steel plate is roll-formed to a cylinder and the edges are welded together (or to a spirale for larger diameter — which will be covered on an extra page). After welding the edges the subsequent roll-forming process transforms the circular section to its desired shape. Typical shapes for structural hollow sections are rectangulars, squares, circular or elliptical shapes. Before the final forming process the shape may be or may be not heated. This is the difference between the hot-finished and cold-finished process. The properties of the product in terms of stress absorbing and microstructural uniformity depends at least on the final forming process.

NOTE: A more descriptive/illustrative introduction for both processes is in preparation.