What are some common defects in DX51D+Z steel coils?
A: There are many other defects, including scratches, passivation spots, zinc particles, thick edges, air knife marks, exposed steel, inclusions, wavy edges, warping, embossing, and roller marks.
What are the effects of zinc particle defects on DX51D+Z steel coils?
A: Zinc particles cause unevenness on the surface of the steel coil, affecting the precision of subsequent processing steps such as spraying and stamping. In severe cases, they may even damage the surface passivation layer, reducing localized corrosion resistance.
What is the core process for accepting DX51D+Z steel coils?
A: The process is as follows: verify the quality certificate → check the appearance and markings → measure dimensions → randomly inspect the surface quality of the zinc layer → test the zinc layer thickness → third-party re-inspection if necessary. Only after passing the inspection can the coil be put into storage.
How to check the surface quality of DX51D+Z during acceptance?
A: The coil should be opened from the inside for inspection. When stacked, at least four sheets should be inspected consecutively, focusing on checking for defects such as incomplete plating, scratches, and rust that could affect its use.
What precautions should be taken when storing DX51D+Z steel coils?
Answer: They should be protected from moisture and rain, packaged in waterproof paper to avoid friction between layers; avoid stacking them too high to prevent indentations; and keep them away from corrosive environments such as acids and alkalis to prevent damage to the zinc layer.