Flat head up/Customers complained that the purchased batch of stainless steel flat plates had obvious head up phenomenon, which affected the use, so the quality objection was raised. The batch of flat plates purchased by the customer is 304, with a thickness of 4.0mm and a specification of 1500×6000mm. Through the on-site inspection, there is indeed a phenomenon of upturning of the head of these batches of tablets, and there are still obvious side waves in the tablet itself. 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 in the process of opening and leveling, because the flat plate itself has large side waves, in order to improve this side wave phenomenon, the operator increased the amount of depression a lot, 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 roller fine-tuning function, so it is basically helpless for the steel coil wave, especially the steel coil with a thickness of 3.0~4.0mm. The consequences of increasing the amount of reduction often can only make the steel plate head upturn, and it also has certain damage to the equipment itself. Strictly implement the operating 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.