Why do packaging bags tend to rupture during transportation?
答：
This is usually due to insufficient tensile strength and puncture strength.
Tensile strength: This indicates the material's ability to withstand tension forces. Consider using a tensile testing machine (LTXLW-500N). Generally, a 500N tensile testing machine can fully meet the requirements.
Puncture strength: For hard and angular contents (such as dried fruits, frozen meat bones), if the puncture strength is insufficient, the bag will be punctured by the internal items. The test was still conducted using a tensile machine with a piercing fixture (LTXLW-500N). The 500N sensor used was sufficient to cover the requirements.
Why do the heat-sealed areas always leak or crack?
答：
This is a problem related to seal strength.
Pressure and temperature: Uneven sealing pressure and excessively high temperature result in the root part being "overcooked" and becoming brittle; while excessively low temperature leads to an unstable seal. The combined test can be conducted using the heat sealing tester (LTH-H3) and the tensile tester (LTXLW-500N).
Heat adhesion force: On the automatic filling production line, when the material drops, the sealing part is still warm. If the "heat adhesion force" is insufficient at this time, the seal will immediately break. This still requires a combined test using a heat sealing tester (LTH-H3) and a tensile testing machine (LTXLW-500N).
How can one determine whether a certain packaging can prevent food from getting damp?
答：
The water vapor transmission rate (WVTR) needs to be measured.
For items that are prone to moisture, such as biscuits and milk powder, the lower the WVTR value, the better the moisture-proof performance. Usually, the tests are conducted using the weighing method or the electrolysis method. The water vapor transmission test equipment (LTWTC-203H) can be used.
Why do the packaged rolls often "deviate" or get stuck in the automatic packaging machine?
答：
This is usually due to an inappropriate **coefficient of friction (COF)**.
Too slippery (COF too low): It is prone to cause stacking and sliding of products, or deviation during winding.
Too thick (COF too high): The packaging film experiences excessive resistance during transportation, resulting in inability to pull it or inability to open the bag opening.
Experience value: In the industry, it is generally required that the friction coefficient of the inner and outer surfaces of the packaging film be controlled within the range of 0.2 - 0.4. This can be tested using the friction testing machine LTMXS-06. Usually, it is conducted in accordance with ASTM D1894 or ISO 8295 standards.
Is the uniformity of the thickness of the composite film important?
答：
This is extremely important. Excessive thickness deviation will directly affect the barrier performance and the subsequent heat sealing quality. Monitoring multiple points using a high-precision thickness gauge is a fundamental step. The LTCHY-HS thickness measuring device from LinkTesting is an excellent choice.
