Plastic calender is mainly used in the production of various types of plastic films and PVC calendered artificial leather products. Due to the requirements of calendering product technology or product quality, various special or new plastic calendering production lines have emerged. In order to meet the requirements of different product processing technology and adapt to high-speed requirements, calendering auxiliary machines have also derived many structural forms.

Definition

Plastic calender is mainly used in the production of various types of plastic films and PVC calendered artificial leather products. It usually has four main rollers or five main rollers to press the plastic material evenly.

Process

The process of the plastic film production line is: feeding-kneading-mixing-open refining-filtration-calendering-embossing-cooling-winding

Development

Plastic calender and its linkage auxiliary machines constitute the plastic calender production line, which is one of the basic equipment in the production process of plastic products and belongs to large-scale high-precision equipment. Calenders have been used in plastic processing for more than 100 years. During this period, they have been continuously improved and now present new characteristics.

(1) Large-scale As the width of products is required to be wider and wider, the specifications of plastic calenders are also constantly increasing. At present, large plastic calenders with a roller width of four or five meters have been widely used. In addition, in order to obtain wide-width products, stretching and tentering processes and equipment are also used to produce films with a width of more than 4500mm. (2) The biggest advantage of high-speed calendering technology is precision, continuity and high efficiency. The working line speed of this process is generally around 100 m/min, and new machines can reach 200-250m/min, and even exceed 300m/min. The annual processing capacity of an ordinary plastic four-roller calender can reach 5000-10,000 tons. (3) Precision calendering products have higher and higher quality requirements, which requires calendering equipment to be more precise. Ways to achieve this goal include:

(4) High automation

In addition to the above-mentioned online monitoring and automatic closed-loop feedback control of the system related to the calender and product thickness, the plastic calender production line is also equipped with a high-automatic control system combining electricity, liquid and gas.

(5) Diversified structure

Due to the requirements of calendering product technology or product quality, various special or new plastic calendering production lines have emerged. For example: multi-roller calender (five-roller, six-roller, seven-roller calenders with various roller arrangements, etc.), different-diameter roller calenders (the diameters of the rollers of the calender are designed to be different to eliminate the cumulative effect of roller diameter errors), planetary roller calenders, etc.

In order to meet the requirements of different product processing technology and adapt to high-speed requirements, calendering auxiliary machines have also derived many structural forms. For example, in order to adapt to different precision and thickness, large diameter cooling roller devices and small diameter cooling roller devices are equipped; the winding device is equipped with friction winding, center winding, and in order to meet the needs of high-speed large-diameter products, friction winding plus auxiliary center winding and other structures are adopted; and the cutting device, whether it is a flying knife or a punching and shearing structure, has electric, pneumatic and electric heating forms.