Views: 3 Author: Site Editor Publish Time: 2022-09-09 Origin: Site
At present, the vacuum aluminum plating equipment used for plastic film in the market mainly has two types: winding type and suspension type. However, whether it is winding type or suspension type, it is generally composed of vacuum system, evaporation system, film winding system, cooling system, control system and other main parts.
The vacuum system is composed of mechanical pump, roots pump and diffusion pump. The vacuum pumping process is divided into three stages. First, the mechanical pump performs initial pumping, and the roots pump works after reaching a certain vacuum. When the vacuum in the vacuum chamber reaches a certain vacuum (10-2mbar), the diffusion pump is turned on. The diffusion pump further improves and maintains the high vacuum in the vacuum chamber (10-4mbar) to meet the needs of evaporation production.
The evaporation system is composed of evaporation boat holder (electrode), evaporation boat transformer, evaporation boat, aluminum coil bracket, aluminum wire conveying motor, etc. During evaporation, the evaporation boat is fixed on the holder for heating. In normal production, the temperature of the evaporation boat is 1300-1400 ℃, and the high-purity aluminum wire is continuously sent to the evaporation boat by the conveying motor and vaporized.
The film winding system is mainly composed of unwinding section, rewinding section, flattening roll and other components. Its function is to transport the base film to the vapor deposition area for vapor deposition at a certain speed and tension, and then wind the aluminum coated film into a cylindrical roll. By controlling the process parameters such as the speed and tension of the film winding, and the angle of the flattening roll, wrinkles can be avoided and a neatly wound film roll can be obtained.
The cooling system is mainly composed of cold well, coolant, cooling roller and other components. Its main function is to provide the required cooling temperature (- 20-15 ℃) during (or after) the evaporation of the film, so as to prevent the film from being heated and deformed. The cooling liquid used in the cooling system is water / ethylene glycol mixture or brine mixture. During evaporation, the cooling liquid is cooled to the required temperature by a cold well, and then conveyed to the cooling roller through a pipe. Then, the cooling roller cools the aluminized film.
The control system consists of tension control, speed control, evaporation control, aluminum layer thickness control and other subsystems. During the evaporation production process, the tension of the film, the running speed, the state and evaporation capacity of the evaporation boat, and the thickness of the aluminum plating layer can be automatically adjusted and controlled by the control system.