Development of cold rolled sheet production technology
The production process of cold rolling mills is basically similar, but the cold rolling methods and methods have undergone fundamental changes. There are five main production processes in cold rolling mills, of which the first and second methods are available at home and abroad, but have been gradually eliminated.
The first method uses a single steel plate production in a single rack, and the entire process from raw materials to finished product production is carried out in a single steel plate manner. This production method has low output, poor quality and low yield.
The second method is the roll production method. This production method has higher output, but the post-rolling process is relatively backward.
The third method is the coil production method, which is currently used by many single-stand four-high reversing rolling mills in China.
The fourth method is the modern cold rolling production method, which appeared in the 1960s. The cold rolling mill is equipped with 2 decoilers, 2 post-rolling tension coilers and automatic belt threading devices, and adopts new technologies such as quick roll change, hydraulic pressure, roll bending device, and computer automatic control. my country's Wuhan Iron and Steel Group, Anshan Iron and Steel Group Co., Ltd., Panzhihua Iron and Steel Group Co., Ltd., and Shougang Group Co., Ltd. all have such rolling mills.
The fifth method is a completely continuous cold rolling production method, which can be divided into 3 types:
1. Single fully continuous rolling mill. Electromechanical equipment such as welding machines and loopers are installed in front of the conventional cold tandem rolling mill to achieve uninterrupted rolling of cold-rolled strip steel.
2. Combined full continuous rolling mill. A single full continuous rolling mill combined with a pickling unit is called a pickling combined full continuous rolling mill; a single full continuous rolling mill combined with a continuous annealing unit is called an annealing combined full continuous rolling mill.
3. Fully combined full continuous rolling mill. It is the latest cold rolling production process that combines a single fully continuous rolling mill with a pickling unit and a continuous annealing unit (including cleaning, annealing, cooling, smoothing, and inspection processes). The use of a fully combined fully continuous rolling mill can shorten the time from feeding the cold-rolled plate to producing the finished product from the original 12 days to 20 minutes.
