1. Classification by production method
(1) Seamless pipes - hot-rolled pipes, cold-rolled pipes, cold-drawn pipes, extruded pipes, top pipes
(2) Welded pipes
(a) Classification by process - arc welded pipes, resistance welded pipes (high frequency, low frequency), gas welded pipes, furnace welded pipes
(b) Classification by weld seams - straight seam welded pipes, spiral welded pipes
2. Classification by cross-sectional shape
(1) Simple cross-sectional steel pipes - round steel pipes, square steel pipes, elliptical steel pipes, triangular steel pipes, hexagonal steel pipes, diamond steel pipes, octagonal steel pipes, semicircular steel pipes, others
(2) Complex cross-sectional steel pipes - unequal hexagonal steel pipes, five-petal plum blossom steel pipes, double convex steel pipes, double concave steel pipes, melon seed-shaped steel pipes, conical steel pipes, corrugated steel pipes, shell steel pipes, others
3. Classification by wall thickness - thin-walled steel pipes, thick-walled steel pipes
4. Classification by use - steel pipes for pipelines, steel pipes for thermal equipment, steel pipes for mechanical industry, steel pipes for petroleum and geological drilling, steel pipes for containers, steel pipes for chemical industry, steel pipes for special purposes, and others
5. Classification by transportation temperature: low-temperature pipelines, normal temperature pipelines, medium temperature pipelines and high temperature pipelines.
Alloy Seamless boiler tubes
