By manufacturing process classification

Manufacturing processes for seamless steel pipes can be divided into basic categories such as hot rolling (extrusion), cold rolling (drawing), and hot expanded pipes.

(2) Welded pipes can be categorized by manufacturing process into: straight seam welded pipes, spiral welded pipes, plate-to-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 various other shaped pipes such as complex cross-section pipes, double concave pipes, five-lobed plum blossom-shaped pipes, conical pipes, corrugated pipes, melon-shaped pipes, double convex pipes, and more.

Categorized by application

Steel pipes are categorized by their applications, including: pipeline steel pipes, heat-engine 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 uses.