When packaging products (such as sauce packets, nuts, powdered supplements), the contents are inserted into the sealing area, resulting in an inadequate seal.
答：
Solution：
Equipment modification: In front of the sealing area of the packaging machine, install a compressed air blowing device or a mechanical vibration device. At the moment of sealing, blow away or shake off the residual materials in the sealing area.
Parameter optimization: A two-step sealing method is adopted - the first low-pressure sealing presses and flattens the molten sealing material and extrudes it into the sandwich material, while the second high-pressure sealing ensures the final strength. At the same time, the heat sealing temperature is increased by 5 to 10 degrees Celsius, and the heat sealing time is extended by 0.2 to 0.5 seconds to "melt" and accommodate tiny particles. The QC operator can use the heat seal tester to complete the test process (https://www.linktesting.org/891.html/heat-seal-tester-lth-h3/)
Daily verification: Conduct a dye penetration test every 2 hours (apply dye to the inner wall of the seal and observe for any penetration). Once any contamination is detected, immediately stop the machine and clean the seal silicone strip.
When packaging products with shells (such as walnuts, meat with bones), the sharp parts pierce through the packaging film, leaving small pinholes, which leads to air leakage and moisture absorption.
答：
Solution:
Material upgrade: Replace the inner material from ordinary PE to metallocene polyethylene (mPE) or add a nylon (PA) layer. Increase the puncture resistance index from ≥15N to ≥25N (refer to GB/T 10004).
Structural optimization: The packaging structure is changed from a two-layer composite (such as PET/PE) to a three-layer composite (such as PET/PA/PE), and the excellent puncture resistance property of the nylon layer is utilized as the "bulletproof layer". The operator can conduce the puncture test via the tensile tester with the puncture clamp(https://www.linktesting.org/7007.html/automatic-tensile-tester-xlw-500n/)
Transport protection: Add partitions or cushioning pads inside the outer packaging cartons to prevent the inner packages from colliding and shifting during transportation, thereby reducing the risk of punctures from the outside.
For food packaging films, the oxygen transmission rate (OTR) is higher than the designed value, resulting in premature oxidation and spoilage of the product within the shelf life, as well as vitamin loss.
答：
Solution:
Incoming material batch inspection: For each batch of high-barrier films (such as aluminized films, EVOH co-extruded films), a batch sampling test using a adifferential pressure oxygen permeability tester is conducted. The OTR value must be ≤ the design standard (such as ≤ 5 cm³/(m²·24h·atm)), and if it does not meet the requirements, the goods will be returned. This test can be conducted by the permeability tester (https://www.linktesting.org/3852.html/gas-permeability-tester-gtc-203h/)
Process monitoring: In the composite process, strictly control the amount of adhesive applied (e.g., increase from 3.5 g/m² to 4.5 g/m²) and the curing time (e.g., extend from 48 hours to 72 hours) to ensure that the adhesive layer is fully cured and free of microscopic pores.
Final product inspection: Conduct destructive oxygen content analysis (using a headspace residual oxygen analyzer) on the packaged finished products. The requirement is that the residual oxygen content within the packaging should be less than 3%. If the standard is exceeded, the film of this batch number should be traced back. The headspace gas analyzer (https://www.linktesting.org/2639.html/headspace-gas-analyzer-ltdk-190/) can be adopted.
The packaging bag was designed with an "easy-tear opening", but the tear line deviated too much, resulting in the bag being completely unable to be opened, which greatly affected the convenience of use and the brand's popularity.
答：
Solution:
Laser easy-tear lines replace mechanical incisions: Using a carbon dioxide laser marking machine on the packaging film, a micro-hole dotted line is drawn along a straight line (only piercing through the outermost layer, not the heat-sealing layer), ensuring that the tearing force is directed along the preset track and achieving a straight tear without any deviation.
Directional matching of film material: During cutting, ensure that the MD direction (longitudinal) of the heat-sealed layer is perpendicular to the tear-off opening direction. Utilize the longitudinal tearability of the PE film to assist in straight-line tearing. The tearing test can be conducted by the Elmendorf Tearing Tester (https://www.linktesting.org/835.html/elmendorf-tearing-tester-ltld-1000z/)
Online tensile testing: On the packaging line site, an electronic tensile machine is used to test the initial tearing force and tearing elongation of the easy-tear opening. The required tearing force should be within a comfortable range of 2 to 5N, and the deviation of the tearing trajectory should be ≤ 2mm.
Visible scratches, white spots or ink stains appear on the surface of the transparent packaging film. This is particularly evident on the high-transparency film, directly affecting the high-end image of the product.
答：
Solution:
Source cleaning: On all the rollers, forming plates, and sealing rods of the bag-making / filling machine, attach Teflon (Teflon) tape to the metal parts or replace them with ceramic rollers to prevent hard contact scratches.
Static electricity elimination: At the film unwinding and forming sections, install static electricity elimination rods (ion air nozzles) to eliminate the static electricity of the film, prevent the adsorption of dust and debris in the environment, and reduce dirtiness.
Light inspection table: Set up a 45-degree angle inclined light inspection table at the end of the packaging line (lighting intensity ≥ 1000 Lux). Each shift arranges a dedicated person to visually inspect and test in this light. Scratches and dirt will be clearly visible under the oblique light, and any found will be removed immediately. The test can be conducted via the light box (https://www.linktesting.org/6082.html/kbt-d65a-double-light-source-viewer/)
