NF EN1.4438 stainless steel pipe in accordance with stainless steel of United States ASTM standards, belonging to the heat-resisting steel. 317  consist of 19% chromium-containing, 13% containing nickel, 3% molybdenum-containing.

 NF EN1.4438 stainless steel pipe mechanical properties :(GB/T4237-92): yield strength ≥ 177/MPa, ≥ 480/MPa tensile strength, elongation rate ≥ 35%, hardness testing: HBS ≤ 187, HRB ≤ 90, HV ≤ 200