BASIC KNOWLEDGE OF PRODUCTION PROCESS OF PVC PRODUCTS
In order to improve the properties of PVC, various additives should be added in the processing of PVC resin to meet the needs of processing and product properties. In the production of plastic doors and windows profile generally need to add: Heat stabilizer, processing modifier, impact modifier, Lubricant, light stabilizer, fillers and pigments. Although the addition amount of additives is 0.1% to 10% of that of pvc-resin, each of them plays an important role, and the change of the addition amount has a great influence on the properties of the processing and final products. Therefore, not only in the batching to weigh accurate and mixing process to achieve uniformity of materials.
PREPARATION OF MATERIALS
The compounding process of PVC material mainly includes batching, hot mixing, cold mixing, transportation and storage. The methods include manual batching, small scale mode of production for manual transport, and automatic batching, large scale mode of production for automatic transport. In recent years, China's hard PC profile extrusion industry has entered a high-speed development period, the scale of enterprises has been expanding, the annual output of 10,000 tons of enterprises, such as the use of artificial batching material processing methods can not meet the needs of the mass production Material handling automation has become a common practice. The automatic mode of material handling is generally suitable for the professional profile production plant with a production capacity of more than 5000 tons, which has low labor intensity, good production environment and can avoid the artificial error, but with large investment, high maintenance cost and difficult system cleaning Not Suitable for the formula of frequent changes, especially color changes. Enterprises with a production capacity of less than 4000 tons usually adopt the methods of manual batching, transportation and mixing. The biggest problem of artificial batching is the high labor intensity, batching, mixing dust pollution, but small investment, production flexibility.
The automation of material handling refers to a complete set of PC batching and mixing production line, which is based on the computer-controlled automatic batching system, assisted by pneumatic conveying and combined with hot and cold mixers. This technology has been introduced into China since the middle of 1980s, and has been applied in some large-scale enterprises. The advantages of this technology are high batching accuracy, high production efficiency, less pollution, to meet the needs of mass extrusion production. At present, some factories in our country can produce this kind of computer-controlled automatic batching system.