The so-called spring zinc color coating joint production line is the process of galvanizing and then color coating after the base plate is rolled on.
Its main features are:
(1) The original passivation and oiling procedures of the exit section of the galvanizing line are omitted
(2) The degreasing and cleaning process of the color coating line is omitted;
(3) It saves manpower, material resources and time in the transportation process from galvanizing to color coating line.
The joint production line is usually equipped with stretch bending straightening equipment between the galvanizing and color coating processes to ensure the quality of the plate shape entering the color coating section, so that the color coating will not have quality problems such as missing coating. However, because of the large number and complexity of equipment, the layout of this unit increases the probability of fault shutdown and is prone to product quality accidents. Galvanizing color coating joint production line is divided into hot galvanizing color coating joint production line (Figure 1-8) and electro galvanizing color coating joint production line. The color coating process of the two joint production lines is the same, but the composition of the front-end equipment, i.e. galvanizing part is different, one is hot galvanizing, the other is electro galvanizing and other two different processes. According to the data, there are many small and medium-sized zinc plating and color coating joint production lines in China, and there is no project on the scale of hot-dip galvanizing and color coating joint production line.
After 50 years of long development, the production line speed of color steel plate has developed from the initial 15m / min to the current 240m / min. the plate thickness can be between 0.15-2.2mm, and the maximum plate width can be up to 2000mm. At the end of the 20th century, there are more than 400 color steel plate production lines in the world, more than 200 in the United States alone, and the total production capacity of the world has reached 14 million tons
Under the influence of American technology, in the early 1960s, many continuous production lines of color coated steel plates have been put into production in Europe and Japan. Especially in Japan, after the introduction of advanced technology from the United States in the early stage, the production of color steel plates was rapidly increased by absorbing, improving and rebuilding. By the end of the 1970s, the annual production of color steel plates had reached 2 million tons, becoming the leader of color steel plate production in Asia.
In order to further promote the network development of color steel plate industry, as early as 1962, the United States established the world's largest coil coating joint enterprise, the national coil coating Association (NCA), which is an international organization integrating coil coating technology exchange, coil and coating raw material trade, coating equipment supply, product trading and other information. The members of the organization include raw materials (such as coatings, metal coils) and equipment manufacturers for the production of color coated steel plates. In addition to holding regular meetings to discuss and exchange information, special technical forums and new product design competitions are also organized to promote the development and market development of color coated steel plates, collect and publish statistics of production and sales, formulate and publish relevant standards, technical manuals and publications, which play a good role in promoting the development of color coated steel plates. At present, the number of its members has reached more than 160, coming from large-scale color steel plate and color aluminum plate production and manufacturing enterprises all over the world. Baosteel company of China is one of them, and the scale of the organization is quite large.
In Europe, coil coating has developed very mature from 1960 to 1965. In 1966, there were 14 color steel plate production lines in Europe, which are distributed in Sweden, Germany, Britain, Belgium, Switzerland, France and other countries. In 1967, ECCA was founded in Brussels, Belgium. This association based on the development of science and technology is composed of more than 80 coil coating manufacturers, more than 50 coating manufacturers, 40 raw material suppliers and more than 20 equipment manufacturers. The aim of the association is to study and promote the production and use of color coated steel plates. At the end of the 20th century, the total annual production of color coated steel plates in Europe has reached 3.9 million tons