What are the applications of Q235 steel coils in municipal construction?
A: They are used in municipal supporting steel structures such as streetlight poles, traffic barriers, underground pipe gallery supports, and sewage treatment equipment housings.
How should Q235 steel coil grades be selected for buildings in low-temperature areas?
A: For temperatures above -20℃, select Q235C; for temperatures ≤ -20℃, select Q235D to ensure low-temperature impact toughness and avoid brittle fracture.
Can Q235 steel coils be used in fire-resistant building components?
A: They are not fire-resistant themselves and require fire-retardant coatings/coverings to meet building fire protection specifications (e.g., fire resistance rating 1-3 hours).
What are the acceptance items for Q235 steel coils upon arrival at the construction site?
A: Verify the quality certificate (grade, grade, mechanical/chemical properties); visual inspection (no cracks, rust, pitting); re-measure dimensions (thickness, width, flatness); sample for tensile, cold bending, and impact tests (according to specifications).
What are the common quality defects of Q235 steel coils and their impact on buildings? A: Corrosion (reduces load-bearing capacity and affects welding); uneven thickness (uneven stress on components); edge cracks (processing cracks, structural hazards); inclusions (welding cracks, substandard mechanical properties).