Brief introduction of the task of the pickling line for packaging steel strip

Brief introduction of the task of the pickling line for packaging steel strip
　　Hot rolled coils are cold rolled billets. Because the final rolling temperature of the hot-rolled coils is about 800°C or more, iron scale is formed on the surface. One of the purposes of cold-rolled steel strip is to obtain good surface properties. Therefore, the iron oxide scale must be removed before cold milking, which is the first purpose of the pickling operation. The tasks completed by pickling can be summarized as follows:
　　 1. Remove surface oxide scale
　　 There are physical (mechanical) methods and chemical methods to remove surface oxide scale. For the treatment of cold-rolled billets, chemical methods that can increase the surface properties are generally used, that is, pickling. The most used acids are hydrochloric acid and sulfuric acid. Recently, most of the hydrochloric acid lines are used. It has a short processing time and good quality. There are also chemical methods, supplemented by physical methods, and the two methods are used together.
　　2. Larger coils
　　 In order to increase the work rate and the yield rate in the next work, and to make more effective use of the storage space of the factory, 2-3 hot-rolled coils are welded together to increase the cold-rolled coils. The welding machine generally adopts a flash butt welding machine with a short operating time and a firm welding part.
　　3. Oiling
　　The purpose of oiling is to prevent rust, prevent scratching of ginseng and provide auxiliary lubrication during rolling, and pre-coat a layer of oil on the pickled steel strip.
　　4. Disc edge trimming machine (edge u200bu200btrimming)
　　 According to the requirements of the order, the width of the strip is cut, and in order to avoid rolling accidents caused by the change of the width of the hot-rolled coil, the edge is cut.
　　5. Management of properties of hot-rolled coils
　　 The inspection of the properties (surface defects, plate shape, coil shape, etc.) of the hot-rolled coils is to improve the quality of raw materials and thus the quality of finished products.
　　The pickling line is located between the hot rolling process and the cold rolling process. In terms of mutual quality management, it can be said that it is a very important line.