GB/T 4171 Q355GNH grade steel is a kind of weathering steel or atmospheric corrosion resistant steel. Q355GNH steel plate is a high weathering steel, delivered in hot rolled, controlled rolling, or normalized condition. GB/T 4171 standard specifies the size, shape, weight and allowable deviation of weather-resistant structural steel, technical requirements, test methods, inspection rules, packaging, marking and quality certificate.
Compared with weldable weathering steel, GB/T 4171 Q355GNH steel has better atmospheric corrosion resistant property. Q355GNH plate is mainly used for steel structures exposed to the atmosphere such as railways, vehicles, bridges, and towers. Q355GNH steel can also be used to manufacture steel structure parts such as containers, railway vehicles, oil derricks, seaport buildings, oil production platforms and chemical petroleum equipment.
GB/T 4171 common grades: Q235NH, Q295NH, Q355NH, Q415NH, Q460NH, Q500NH, Q265GNH, Q295GNH, Q310GNH, Q355GNH
GB/T 4171 Q355GNH Steel Plate (% max., by weight)
| Grade |
Carbon |
Silicon |
Manganese |
Phosphorus |
Sulfur |
Copper |
Chromium |
Nickel |
| Q355GNH |
0.12 max. |
0.25-0.75 |
1.00 max. |
0.07-0.15 |
0.020 max. |
0.20-0.55 |
0.30-1.25 |
0.65 max. |
GB/T 4171 Q355GNH Steel Plate Mechanical Properties
| Grade |
YieldStrength(MPa) |
TensileStrength(MPa) |
%Elongationin2in.(50mm)min |
| Q355GNH |
355 |
490-630 |
22 |
What Does Q355GNH Stand for?
Q: the first letter of Chinese spelling yield strength(Qufu).
355: the number is the min. Yield strength value in N/mm²(MPa).
GNH: the first letters of high weathering steel in Chinese spelling(GaoNaiHou).
All in all, the steel grade Q355GNH indicates its application (atmospheric corrosion resistant steel).
What are the Advantages of GB/T 4171 Q355GNH Steel Plate?
Due to the corrosion-resistant elements adding such as copper and nickel, Q355GNH weathering steel has the characteristics of high-quality steel for toughness, plastic elongation, forming, welding, abrasion, high temperature and fatigue resistance. At the same time, Q355GNH steel plate has rust resistance, which makes the components resist corrosion and prolong life, reduce thinness and reduce consumption.
