The history of plastic steel windows
Plastic windows were first developed in the late 1950s by West Germany and began production in 1959. The original plastic windows were all simple and rough. With the worldwide energy crisis in 1972, plastic windows with good energy-saving effects in the early 1970s were used extensively, which also promoted the improvement of profile production technology. The performance is improving day by day, from the original single-cavity profile to three-cavity and four-cavity profiles, which also promoted the development of plastic doors and windows in Europe and Asia. According to incomplete statistics, the use of plastic doors and windows in Germany has accounted for 52% of the door and window market, Austria is 48%, and developed countries such as Switzerland, Britain, France and Italy also have 10%-20%; American plastic windows in the seventies At the beginning, the annual growth rate of usage has reached more than 15%. Currently, plastic windows are used in Asia, including Japan, South Korea, Taiwan, Singapore, and Thailand.
China's plastic windows started late, and the quality of calcium-plastic doors and windows produced in the 1970s was not enough. The real plastic window production started from the introduction of equipment in 1983. At that time, the technology was not very advanced. They all used single-cavity or two-cavity structural profiles. With the improvement of the industry in 91 years, a number of extrusion equipment and molds emerged in China. Manufacturers of profiles, assembly equipment, etc.; In 1996, with the birth of the manufacturers of the advanced equipment introduced by the state and newly established in the 1990s, the development of the industry was greatly promoted. At present, there are more than 2,000 extrusion production lines in China, more than 400 profile factories and more than 3,000 assembly plants. The production capacity of profiles in 1999 is 800,000 tons, and the annual assembly of doors and windows is 60 million square meters. A lot of fast-growing industries. Plastic doors and windows are being accepted by users with their excellent performance.
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