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DB-1300-DB-1800
Three layer film blowing machine with horizontal haul off
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3DB-A
Three layer film blowing machine
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ABA
film blowing machine
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2DB-A
Two layer film blowing machine
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DB-B50/55/60/65
Single layer film blowing machine
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DB-A45-700/A50-900
Single layer film blowing machine with printer
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DB-350x2/450x2
T-shirt bag making machine
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DB-600-1000
Side sealing bag making machine
Temperature index and control method of film blowing machine
According to the melting theory of plastics, the screw of the extruder for blown film is divided into three sections: feeding section, melting section, and homogenization section. At the end of the feeding section, when entering the melting section, according to the melting theory, its temperature should be the viscosity flow temperature. The viscosity flow temperatures of various film blowing resins are PP: 164-175 degrees Celsius, PE: 105-135 degrees Celsius, and PA: 195-210 degrees Celsius.At the entrance of the feeding section, it is hoped that the temperature is lower to prevent the resin viscosity flow from blocking the feed port. In addition, the resin is continuously compressed in the feeding section, and the air should be discharged from the feeding port backwards. Depending on the structure of the equipment, although the feeding port is not electrically heated, the heat is transferred through the barrel, and the feeding port temperature is about 50-90 degrees. In this way, the temperature of the feeding section is determined. 50-90 degrees at the entrance, the end is equal to the melting point or viscosity flow temperature, and the temperature can be determined as a proportional linear temperature rise in this section. At the beginning of the melting section, the temperature reaches the viscosity flow temperature to melt. For crystalline resins, the viscosity flow temperature is equal to the melting point temperature. Then, the temperature needs to be continuously increased to continuously compress and increase the melting layer, so that the resin molecular chains are of different lengths and the polymers with different thermal motion energy are melted one after another. Therefore, after the temperature at the end of the melting section is established, it can be determined that the temperature of other parts in this section is linearly increased.
In the homogenization section, it is mainly re-melting homogenization and quantitative constant pressure constant temperature output of the melt. The temperat