Seamless steel pipes without joints around their cross-sections. They are classified into hot-rolled, cold-rolled, cold drawn, extruded, and jacking pipes, each with its own production specifications.

Materials include ordinary and carbon structural steel (Q215-A to Q275-A and 10 to 50 steel grades), low-alloy steel (09MnV, 16Mn, etc.), alloy steel, and stainless acid-resistant steel, etc.

General purpose (used for water, gas pipelines and structural components, mechanical parts) and special purpose (used for boilers, geological exploration, bearings, acid resistance, etc.) categories.