Introduction and application of Q345NS acid-resistant steel plate

Introduction and application of Q345NS acid-resistant steel plate

Q345NS American Standard Boiler Vessel Plate Introduction
Q345NS Acid-Resistant Steel Basic Information: Grade: Q345NS Product Name: Sulfuric Acid Low Temperature Dew Point Corrosion Resistant Steel
Executive Standard: GB/T28907-2012
Place of Origin:
Wugang Q345NS
The size, shape, weight and allowable deviation should comply with GB/T709.
Q345NS acid-resistant steel definition: Q345NS representation:
Q - the first letter of the Chinese pinyin of the word "yield" in yield strength;
345—the buckling limit of steel, unit: MPa;
NS—The first letter of Chinese pinyin for "resistance" and "acid" respectively.
Q345NS acid-resistant steel refers to the addition of a certain amount of alloying elements to the steel, so that when the steel is exposed to sulfuric acid gases (such as emitting steel chimneys containing exhaust gases), the corrosion resistance of sulfuric acid generated by the combination of sulfur trioxide and water below the dew point is increased.

Chemical composition

Tabulation: Depu Steel Date: 2024-01-18

C	Si		Mn	P	S	Cr	Cu	Sb
≤0.15	≤0.55	≤0.12	≤0.035	≤0.035	0.3-1.2	0.2-0.5	≤0.015

Note:
(1): In order to improve the properties of steel, other trace alloying elements other than the above table can be added, and the data comes from the network and is for reference only.
(2): The allowable deviation of the chemical composition of the finished steel plate shall be in accordance with the provisions
of GB/T222 Q345NS corrosion resistance
of acid-resistant steelAccording to the test method specified in JB/T7901, the corrosion rate is not more than 10mm/a (0.89mg/cm²*h, 30% relative to Q235B) under the conditions of temperature 20 °C, sulfuric acid concentration 20% and total immersion for 24 hours; Under the condition of 70°C and total immersion for 24 hours, the average corrosion rate is not more than 250mm/a (22.4mg/cm²*h, 50% relative to Q235B). Q345NS container plate production process:
electric furnace smelting→LF/VD furnace refining→ ingot → cleaning→ ingot heating→ rolling plate → flaw detection→ normalizing → steel plate grinding→ cutting and sampling→ performance inspection → warehousing