Q: What are the applicable thicknesses for cold and hot working of Q235 steel?
A: Cold working ≤ 4mm (e.g., cold-pressed plates); Hot working ≥ 4mm (e.g., angle steel, channel steel, steel pipes).
Q: How to reduce deformation after welding Q235?
A: Symmetrical welding, segmented back welding, preheating before welding, post-weld heat treatment, and tooling fixation.
Q: What tests are required for Q235 before it leaves the factory?
A: Chemical composition, tensile testing, bending testing; B/C/D grades plus corresponding temperature impact testing.
Q: What are the sampling locations and notch types for the impact test of Q235?
A: Longitudinal sampling, V-notch, impact energy ≥ 27J (B/C/D grades).
Q: How to determine the appearance quality of Q235 steel plates?
A: No cracks, folds, scabs, or delamination; local defects are allowed to be repaired, with a depth ≤ 50% of the negative deviation of the steel plate thickness.