1. Introduction of Q315NS acid-resistant steel:
Brand: Q315NS
Product name: Sulfuric acid resistant steel for low temperature dew point corrosion
Executive standard: GB/T28907-2012
The size, shape, weight and allowable deviation of Q315NS should comply with GB/T709.

2. Definition of Q315NS acid-resistant steel:
Q315NS expression method: Q—the first letter of the Chinese pinyin of “qu” in the yield strength; 315—the lower yield limit of steel, in MPa; NS—the first letter of the Chinese pinyin of “resistant” and “acid” respectively. Q315NS acid-resistant steel refers to adding a certain amount of alloying elements to the steel to increase the resistance to the sulfuric acid generated by the combination of sulfur trioxide and water below the dew point when the steel is exposed to sulfuric gas (such as a steel chimney containing exhaust gas). Corrosion performance.

3. Chemical composition of Q315NS acid-resistant steel:
Material CSiMnPSCrCuSbQ345NS≤0.15≤0.55≤1.20≤0.035≤0.0350.30-1.200.20-0.50≤0.15

4. Mechanical properties of Q315NS acid-resistant steel: material yield strength Ra MPa tensile strength Ra MPa elongation after fracture A%Q315NS≥315≥440≥22Q345NS≥345≥470≥20

5. Corrosion resistance of Q315NS acid-resistant steel:
According to the test method specified in JB/T7901, the corrosion rate is not more than 10mm/a (0.89mg/cm²*h, 30% relative to the corrosion rate of Q235B under the conditions of a temperature of 20℃, a sulfuric acid concentration of 20%, and full immersion for 24 hours) ; Under the condition of temperature 70℃ and full immersion for 24h, the average corrosion rate is not more than 250mm/a (22.4mg/cm²*h, 50% relative to Q235B corrosion rate).