A seamless stainless steel pipe is a long piece of steel with a hollow cross-section and no seams around it. It is made from ingots or solid billets that are pierced to make a burr pipe, which is then hot rolled, cold rolled or cold dialed. Due to its lack of welded seams, the overall structure is uniform and stronger, able to withstand higher pressures and stresses. The dimensional accuracy is relatively high, with smaller tolerances on inner and outer diameters and good roundness. The production process is complicated and the cost is high.

Stainless steel welded pipe is a kind of stainless steel strip or plate processed into a tube by welding process. It is made of stainless steel plate through the process of coiling, welding, shaping, etc. The welded seam can be straight or spiral seam. High production efficiency, flexible size specifications, good welding performance. Pressure-bearing, precision and anti-corrosion properties are less than seamless pipe, but the cost is lower.

304 stainless steel is a general-purpose stainless steel material with better rust resistance than 200 series stainless steel materials. High temperature resistance is also better, up to 1000-1200 degrees.304 stainless steel has excellent corrosion resistance and good intergranular corrosion resistance, high strength and toughness, smooth and beautiful surface, easy to process. It is mainly used in building decoration, kitchenware and tableware, food processing equipment, medical equipment, chemical equipment, automobile parts and so on.

Compared with 304 stainless steel, 316 stainless steel has a molybdenum content of 2-3%, which makes it more resistant to corrosion by acids, alkalis, salts and other chemicals, and is especially resistant to chlorides, which makes it suitable for a variety of harsh corrosive environments. It is usually used in pulp and paper equipment, heat exchangers, dyeing equipment, film processing equipment, pipelines, building exterior materials in coastal areas, and bracelets and cases of high-grade watches.

With a titanium content of not less than 5 times the carbon content, Type 321 stainless steel offers oxidation resistance at 816°C (1500 °F) and higher creep and stress fracture properties than 304 and 304L alloys. It also has good low-temperature toughness. It is primarily used in aerospace, petrochemical, power, automotive exhaust, and food processing equipment.

405 Stainless steel belongs to ferritic stainless steel, with certain magnetic properties, and a remarkable feature is its ductility, so that the metal will not crack or break when doing bending and rolling and other molding processes. It is mainly used in building decoration, automobile industry, home appliance industry, food processing industry, chemical equipment and so on.