What method can be used to cool the film blowing machine

The performance of Dalian film blowing machine and film blowing technology are two major factors restricting the quality of blown film. The former belongs to hardware facilities. We should pay attention to the maintenance of the film blowing machine to improve the service life of the machine. The improvement of the latter is mainly affected by practical experience. In order to improve the working efficiency of Dalian film blowing machine, using reasonable cooling methods according to different situations is an effective way to improve the working efficiency and reduce the production cost.

In the high-temperature melting state, the materials of the film blowing machine pass through an annular die and then are extruded by air expansion. At this stage, the tubular film will undergo an intense cooling process in the forming section (the area between the die outlet and the cooling line), so a cooling system needs to be set here. There are two cooling methods for film blowing machine: external cooling and internal cooling.

1. Internal cooling is achieved by radiating heat directly through membrane bubbles. Because the air flow rate in the membrane bubble is relatively low and irregular, external cooling is dominant.

2. The external cooling method was first applied. Under the action of the cooling ring, the cooling air was released from a circular ring along the extrusion direction and the outer surface of the membrane bubble to produce uniform cooling air around the ring. Inside the cooling ring, the air at the upper port is discharged at a faster average speed than that at the lower port. The shape of the membrane bubble is consistent with that of the air cooling ring, which increases the average flow rate of the air and thus improves the heat transfer.

In order to ensure the quality of film products in the blowing process of film blowing machine, the stability of film bubbles before film formation must be considered in order to effectively control the qualified rate of products. The output of blown film of film blowing machine is not only restricted by film bubbles, but also takes into account the cooling system of film blowing machine. A perfect cooling system needs the reasonable configuration and stability of the film blowing machine.