First, the temperature is not enough: the working principle of the shrink machine is actually relatively simple, that is, the matching of speed and temperature, when the temperature is low, the surface of the product will appear folds. Generally POF shrink film can be used at a temperature of about 150 degrees;
Second, the shrinkable film is not punched: this situation is mainly for the POF shrinkable film full package, when the product needs to be fully packaged, the shrinkable film surface must be pierced with some small holes, so that the gas inside the film can be emitted through the small hole during the contraction, otherwise the gas is in the film, there will be a bulging membrane;
Third, the furnace size is not suitable: the furnace size is not suitable in two cases, one is that the furnace is too large, and the other is naturally too small. The situation of the furnace is that the temperature of the product is relatively small, so the shrink packaging machine needs to be increased to a very high temperature in order to shrink better;
Fourth, the speed mismatch: the shrinkage of the product is different, the length of the furnace is different, the furnace temperature is different, the required conveying speed will be different, the longer the furnace, the higher the temperature, the faster the speed, which needs to be determined according to the demand of the product;
Fifth, the quality of the heat shrink film is too poor, or the width is not appropriate: the shrink film applicable to the shrink film needs to meet certain requirements, if the quality of the shrink film produced by the POF shrink film manufacturer is too poor, then the effect of contraction must be bad, either there are folds, or it will burst.