The customer complained that the purchased batch of stainless steel flat plates had obvious head upturning phenomenon, which affected the use, so the quality objection was raised. The batch of flat plates purchased by the customer is 304.1, the thickness is 4.0mm, and the specification is 1500×6000mm. Through the on-site inspection, there is indeed a phenomenon of upturning of the heads of these batches of tablets, and there are also obvious side waves on the tablets themselves. The upturn of the board head is generally caused by the excessive amount of leveling roller pressing during opening. For steel coils of various thicknesses, the Kaiping reduction has corresponding setting parameters. Generally speaking, such quality problems will not occur, so consult the processing records. It turned out that during the flattening process, the flat plate itself had large side waves. In order to improve this side wave phenomenon, the operator increased the amount of depression by a large amount, resulting in the upturn of the head. In fact, the increase in depression did not bring much improvement to the side waves. This medium plate opening and leveling equipment has a thicker roll diameter and no intermediate roll fine-tuning function, so it is basically powerless for steel coil waves, especially steel coils with a thickness of 3.0~4.0mm. The consequences of increasing the amount of reduction can often only make the steel plate head upturn, and it also has certain damage to the equipment itself. Strictly implement the operation regulations. For these steel coils with large waves, and if it is confirmed that they cannot be improved very well, the customer should be notified before processing, and the processing should be carried out after asking the customer for their opinions.