GB/T 4171 Q355NH grade steel is a kind of weathering steel or atmospheric corrosion resistant steel. Q355NH steel plate is a weldable 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 high weathering steel, GB/T 4171 Q355NH steelhas better welding performance. Q355NH plate is mainly used for steel structures exposed to the atmosphere such as railways, vehicles, bridges, and towers. Q355NH 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.
Common grades: Q235NH, Q295NH, Q355NH, Q415NH, Q460NH, Q500NH, Q265GNH, Q295GNH, Q310GNH, Q355GNH
GB/T 4171 Q355NH Steel Plate (% max., by weight)
| Grade |
Carbon |
Silicon |
Manganese |
Phosphorus |
Sulfur |
Copper |
Chromium |
Nickel |
| Q355NH |
0.16 |
0.5 |
0.5-1.5 |
0.03 |
0.03 |
0.25-0.55 |
0.40-0.80 |
0.65 |
GB/T 4171 Q355NH Steel Plate Mechanical Properties
| Grade |
YieldStrength(MPa) |
TensileStrength(MPa) |
%Elongationin2in.(50mm)min |
| Q355NH |
355 |
490-630 |
22 |
What Does Q355NH Stand for?
Q: the first letter of Chinese spelling yield strength(Qufu).
355: the 355 is the min. Yield strength value in N/mm²(MPa).
NH: the first letters of weathering steel in Chinese spelling(NaiHou).
All in all, the steel grade Q355NH indicates its application (atmospheric corrosion resistant steel).
What are the Advantages of GB/T 4171 Q355NH Steel Plate?
Due to the corrosion-resistant elements edding such as copper and nickel, Q355NH 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, Q355NH steel plate has rust resistance, which makes the components resist corrosion and prolong life, reduce thinness and reduce consumption
