What is the elongation (δ5) requirement for Q355 steel plate?
A: The national standard requires δ5 ≥ 20% to ensure good plasticity and cold working properties of the steel plate.
Does the yield strength change for Q355 steel plates of different thicknesses?
A: Yes, it changes. The thicker the plate, the lower the lower limit of the yield strength. The national standard specifies:
≤16mm: ≥355MPa; 16-40mm: ≥345MPa;
40-63mm: ≥335MPa; 63-80mm: ≥325MPa;
80-100mm: ≥315MPa.
Does Q355 steel plate require flaw detection, and what are the grade requirements?
A: No flaw detection is required for regular deliveries. For export/custom engineering projects, UT ultrasonic flaw detection can be requested. Commonly used grades are: GB/T 2970-2016 Grade I and Grade II, or ASTM A435 Grade A/B.
What are the surface quality grades of Q355 steel plates?
A: They conform to GB/T 3274, and are divided into ordinary surface (FA) and good surface (FB). FA allows for minor surface defects, while FB requires fewer defects and a smoother surface.
What are the common thickness, width, and length specifications of Q355 steel plates?
A: Standard export specifications; non-standard specifications can be customized:
Thickness: 3mm-300mm (medium-thick plates 3-60mm, thick plates 60-300mm);
Width: 1000mm-2500mm (mainstream 1500/1800/2000/2200/2500mm);
Length: 2000mm-12000mm (mainstream 6000/8000/10000/12000mm).