Factors affecting the cooling efficiency in FFS blown film lines

FFS (Form, Fill and Seal) heavy duty bags can be used for bulk packing, to pack products like resins, grains, fertilizers, sugar, salt, etc.

These are entire plastic film rolls that are produced by blown film lines, for FFS heavy duty bags, before these film rolls are mounted to the automatic packaging lines to fill the content and then sealed as packaged end products. This method of packaging is faster than the traditional woven bags packaging, as it minimizes human labour, and automate significantly to improve production efficiency.
The entire roll of FFS film

FFS films are thicker than other type of films. The thickness is about 140 to 160 microns. In recent years, the issue of environmental conservation is discussed passionately by all industries. It urges people to reduce the amount of material used in production and to recycle the wastes to be reused in other products. In FFS packaging, producing 100 to 120 microns thickness films is the trend now. However, reducing the thickness might affect the properties of the films. To ensure that the films are suitable for use in packaging lines, we can vary the film formulation to make properties like puncture resistance, drop impact, anti-block, and sealability, to meet the required standard for packaging.

As the FFS heavy duty bag films are thicker and the output of the film production line is a fast 300 to 500 kg per hour, it requires longer cooling time before it will be flattened by nip rolls, so as to ensure that it has good opening property. Therefore, the FFS film production line is recommended to be 17 to 19 meters in height.

Due to the limit at this customer’s factory, this FFS production line was designed to be only 11.3 meters in height. The output will obviously be affected, as it cannot have sufficient cooling time. In addition, the film travel from forming, to the nip rolls, is less than 30 seconds. It is therefore difficult to cool the film from 180 degrees Celsius to ambient temperature in an extremely short time and still preserve its film properties. Besides adjustments to the cooling unit, changing the material formulation is also a solution, to change the melt point, the melt index, as well as the ratio of each film layer components to vary the results achieve the required film properties.

♦To watch the video about running test from our Youtube Channel

The entire roll of FFS film