321 Stainless steel pipes mainly used to produce high pressure and above pressure of steam boiler pipeline, with of quality carbon pigment structure steel, and alloy structure steel and not rust heat-resistant seamless steel tube, and these boiler tube often worked in high temperature and high pressure , pipe will occurred oxidation and corrosion in high temperature flue gas and steam , therefore , it has high lasting strength, and high anti-oxidation performance, and has good of organization stability.

Chemical composition Carbon C: ≤ 0.08 Si Si: ≤ 1.00 Manganese Mn: ≤ 2.00 S S: ≤ 0.030 P P: ≤ 0.035 Chromium Cr: 17.00 ~ 19.00 Ni-Ni: 9.00 ~ 12.00 Ti Ti: ≥ 5 × C% [2] Mechanical Properties Tensile strength σb (MPa): ≥ 520 Conditions yield strength σ0.2 (MPa): ≥ 205 Elongation δ5 (%): ≥ 40 Reduction of area ψ (%): ≥ 50 Hardness: ≤ 187HB; ≤ 90HRB; ≤ 200HV