By manufacturing process classification

Manufacturing processes for seamless steel tubes can be categorized into the basic types: hot rolling (extrusion), cold rolling (drawing), and hot expansion.

(2) Welded pipes can be categorized by manufacturing process into: straight seam welded pipes, spiral seam welded pipes, plate-and-roll butt-welded pipes, and hot-expanded welded pipes.

Categorized by shape

Steel pipes can be categorized by shape into round pipes, square pipes, rectangular pipes, octagonal pipes, hexagonal pipes, D-shaped pipes, pentagonal pipes, and other special-shaped steel pipes, complex cross-section pipes, double concave pipes, five-petaled plum blossom-shaped pipes, conical pipes, corrugated pipes, melon-shaped pipes, double convex pipes, and more.

Categorized by Use

Steel pipes are categorized by use into: pipeline steel pipes, thermal equipment steel pipes, machinery industry steel pipes, oil and geological drilling steel pipes, container steel pipes, chemical industry steel pipes, and steel pipes for special purposes, etc.