As a major category, packaging bags for nuts are widely used in the industry. Bags of this type commonly include the standing type and tri-side sealed type, or the aerated type and vacuumized type. Analysis on the breakage at the thermal seals of nuts packaging bags is detailed below:
I. Due to the Packaging Material Composite films used for the packaging bags are of poor peel strength, i.e. poor composite fastness between single layers of the composite film, which is easy to cause layering of the composite film. For relatively high strength for thermal sealing at the seal and under the impact of the contents or extrusion of external force, the composite film may be separated to cause leakage or breakage at the seal. It could be verified via explosion pressure(positive pressure method) and peel strength test. II. Hazards Incurred by the Production Process For improper parameter settings of the thermal sealing equipment, it’s easy to bring forth improper sealing(i.e. unsealed seal, easy to separate) and excessive sealing(i.e. excessive sealing to cause breakage of the seal foot), thus resulting in leakage and breakage of the seal. It could be verified via the airtightness(negative pressure method) and the thermal sealing strength. Due to unique features of nuts packaging bags, either the techniques and materials, or the material thickness and thermal sealing method will be treated specifically during the production of nuts packaging bags. In the test of finished packaging bags, we would normally set a strict test for the strength and airtightness of the material to ensure quality of the nuts packaging bags.