Q235 steel coils can undergo cold bending tests? What are the national standard requirements?
A: Yes, cold bending is a passing grade. The national standard requires the mandrel diameter to be 0.5 to 2 times the steel thickness (depending on the thickness). After bending 180°, the sample surface should show no cracks or delamination.
Q235D steel coils: What are the low-temperature impact energy requirements?
A: -20℃ low-temperature impact test (V-notch), single impact energy ≥27J, average value ≥34J, is the core indicator for low-temperature conditions.
Q235A steel coils are not subjected to impact tests. What are the limitations on their application?
A: Due to their relatively high phosphorus and sulfur content, lack of impact requirements, and poor toughness, they are only suitable for static structures without dynamic loads, at room temperature, and without load-bearing capacity. They cannot be used in low-temperature or vibration conditions.
Q235 steel coils are available in hot-rolled and cold-rolled varieties. What are the core differences in their manufacturing processes?
A: Hot-rolled steel coils are made by rolling steel billets at temperatures above 1000℃ and then coiling them. Cold-rolled steel coils are made by pickling and then rolling hot-rolled steel coils at room temperature. Cold rolling results in higher precision and a smoother surface, while hot rolling offers better toughness and lower cost.
What is the standard specification range (thickness/width) for Q235 hot-rolled steel coils?
A: Thickness 1.2mm~25.4mm, width 600mm~2000mm, these are the most commonly used hot-rolled coil specifications in industry.