The development of hot-dip galvanizing production in China has been lagging behind. In the 1950s and 1960s, 13 single-plate flux hot-dip galvanizing units were built, with a capacity of 100,000 t/a. However, due to low output, high cost, poor quality, environmental pollution, and poor economic benefits, Stopped and changed production. From the end of the 1970s, China began to build large-scale broadband hot-dip galvanizing units.
Hot-dip galvanized strip steel has been a scarce variety in the Chinese market. Since the mid-1990s, it has imported about 80-100 million tons per year from abroad. With the development of the domestic economy, especially in the automotive, home appliance and construction industries, the demand for galvanized steel strips has also increased significantly. In the past 20 years, China has built a number of production lines with an annual output of more than 100,000 tons. However, from the process flow, equipment composition to product variety, it is a low-level traditional hot-dip galvanizing unit, which cannot meet the requirements of China. The demand for economic construction and development still requires the construction of new hot-dip galvanizing lines to meet market needs.
Since the 1990s, China's galvanized steel sheet production has made great progress, and the processing capacity of galvanized sheets in China and under construction has reached nearly 3 million tons. The market share of domestic galvanized sheets has increased rapidly, from about 27% in 1996 to around 59% in 1998. The main domestic manufacturers are Baosteel, Wuhan Iron and Steel, Pangang, Handan Iron and Steel, Benxi Steel and other five companies with a total production capacity of over 1.3 million tons.
The main difference between the existing hot-dip galvanizing units in China and the foreign level is that most units do not have pre-cleaning equipment, and the quality of galvanized surface is difficult to guarantee; the existing finishing machines are relatively simple two-roll finishing machines. The steel is four-roller), which can not improve the mechanical properties of the strip better, especially the deep-drawing performance; the existing varieties are single galvanized sheets, and only a small amount of alloyed sheets are far from meeting the market demand.
Hot-dip galvanized steel sheets produced by Chinese manufacturers are mainly used in building materials, light industry, agriculture, transportation and other industries. Due to the limitations of existing hot-dip galvanizing equipment conditions, process technology and the performance of the original board, there are very few galvanized sheets that can be used in the automotive industry.
Characteristics of galvanized steel sheet: galvanizing can effectively prevent steel corrosion and prolong service life. Galvanized steel sheet (thickness of 0.4 to 1.2 mm) is also called galvanized iron sheet, commonly known as tinplate. Galvanized steel sheets are widely used in construction, vehicles, home appliances, daily necessities and other industries.