The Packaging Flatness of The Transparent Film Three-dimensional Packaging Machine Has Been Improved

The packaging flatness of the transparent film three-dimensional packaging machine directly affects the product appearance, sealing performance and transportation stability. It needs to be comprehensively improved from multiple dimensions such as equipment optimization, process adjustment, film material adaptation and process monitoring. The following analysis is conducted from four aspects: factors influencing flatness, improvement methods, solutions to common problems, and maintenance suggestions.

First, the key factors affecting the flatness of packaging

Membrane material characteristics

Uneven thickness: If the thickness deviation of the membrane material exceeds ±5%, it will cause local stretching or relaxation, resulting in wrinkles or waves.

Heat shrinkage: Some film materials (such as PVC and PET) shrink unevenly after heating, resulting in an uneven surface after packaging.

Insufficient stiffness: The film material has poor rigidity and is prone to deformation due to external forces, especially during high-speed packaging.

Equipment structure and operation

Forming mold: Uneven surface of the mold or design flaws (such as too small fillets) can cause stress concentration when the membrane material is wrapped.

Tension control: If the tension of the membrane material during transportation fluctuates by more than ±10%, it will cause uneven stretching, resulting in wrinkles or relaxation.

Heat sealing process: Excessively high sealing temperature or uneven pressure can cause local deformation of the membrane material, affecting its flatness.

Process parameter matching

Speed and temperature: If the speed is too fast, the membrane material may be folded before it cools sufficiently, resulting in thermal deformation. Excessively high temperatures will intensify thermal contraction.

Cooling efficiency: Insufficient cooling will cause the membrane material to continue to shrink after sealing and cutting, damaging its flatness.

Second, methods for improving the flatness of packaging

Membrane material optimization and pretreatment

Select high-stiffness membrane materials: Give priority to using membrane materials with uniform thickness and high stiffness (such as BOPP, OPS) to reduce the risk of deformation.

Heat shrinkage pretreatment: For heat shrinkable membrane materials, the impact of shrinkage can be reduced by pre-stretching or adjusting the heat sealing parameters. For instance, reduce the heat sealing temperature by 5 to 10 degrees Celsius and extend the cooling time to 2 to 3 seconds simultaneously.

Surface coating treatment: Apply anti-static or anti-adhesion coatings on the surface of the membrane material to reduce friction and adhesion during the conveying process.

Equipment adjustment and improvement

Optimization of forming molds

Regularly inspect the flatness of the mold surface. Use a micrometer to measure key parts, and the deviation should be controlled within ±0.05mm.

Increase the fillet radius of the mold (for example, from R0.5mm to R1.0mm) to reduce stress concentration.

Tension control system upgrade

Closed-loop tension control is adopted. The tension is adjusted in real time through tension sensors and magnetic powder brakes/clutches, with fluctuations controlled within ±5%.

Add floating rollers along the membrane material conveying path to buffer tension fluctuations.

Improvement of heat sealing and cooling processes

The segmented heating technology is adopted, and the temperature gradient in the sealing area is controlled (such as 170℃ at the front end and 160℃ at the rear end) to reduce local overheating.

Add cooling air knives or water cooling devices to ensure that the membrane material is rapidly cooled to room temperature after sealing.

Refinement of process parameters

Speed and temperature matching:

Reduce the packaging speed by 10-15% to ensure that the film material has sufficient time to cool and set.

Adjust the heat sealing temperature according to the thickness of the membrane material. For example, the sealing temperature for 25μm membrane material is 160-165℃, and for 50μm membrane material, it is 170-175℃.

Pressure uniformity control

Use a silicone pad or a Teflon-coated heat sealer to ensure that the sealing pressure is evenly distributed.

Regularly check the parallelism of the heat sealing knife, and the deviation should be less than 0.1mm.

Process monitoring and feedback

Real-time flatness detection

Install a laser rangefinder or visual inspection system to monitor the flatness of the packaging surface in real time. An automatic alarm will be triggered when the deviation exceeds 0.5mm.

Data Recording and Analysis

Record parameters such as the thickness, tension, temperature and speed of the membrane material, establish a process database, and optimize the parameter combination through data analysis.

Third, common problems and solutions

The membrane material is wrinkled or wavy

Reasons: Uneven tension, insufficient stiffness of the membrane material, and too small fillet of the mold.

Solution: Optimize tension control, replace the membrane material with high stiffness, and increase the fillet radius of the mold.

There is a local bulge at the sealing area

Reasons: Excessively high heat sealing temperature, uneven pressure, and insufficient cooling.

Solution: Reduce the heat sealing temperature by 5-10℃, adjust the pressure of the heat sealing knife, and increase the cooling time.

The packaging size shrinks.

Reasons: Insufficient thermal shrinkage of the membrane material and inadequate cooling.

Solution: Select membrane materials with low shrinkage rates and extend the cooling time to more than 3 seconds.

The edges are uneven or burrs

Reasons: Wear of the cutting knife, uneven thickness of the membrane material.

Solution: Replace the cutting knife and use membrane material of uniform thickness.

Fourth, equipment maintenance and long-term stability

Daily maintenance

Cleaning: Clean the heat sealing knife, cutting knife and guide roller daily to prevent the accumulation of glue residue or film debris.

Lubrication: Lubricate the transmission components (such as chains and gears) weekly using high-temperature resistant grease.

Inspection: Check the membrane material conveying path daily to ensure there is no jamming or wear.

Regular calibration

Mold calibration: Use a micrometer to check the mold dimensions every month. Make adjustments when the deviation exceeds 0.05mm.

Sensor calibration: Calibrate the tension sensor, temperature sensor and visual inspection system every quarter to ensure measurement accuracy.

Heat sealing tool calibration: Check the parallelism and pressure uniformity of the heat sealing tool every six months. Repair it when the deviation exceeds 0.1mm.

Spare parts Management

Key spare parts reserve: Stock commonly used spare parts (such as cutting knives, heat sealing knives, silicone gaskets) to ensure timely replacement in case of failure.

Spare parts quality: Select spare parts that match the original equipment to avoid affecting the flatness due to spare parts quality issues.

Fifth, suggestions for improving flatness and optimization

Technological upgrade

Automation control: The introduction of PLC and touch screen enables automatic parameter adjustment and self-diagnosis of faults.

Visual inspection system: Install a high-precision visual inspection system to monitor the flatness of packaging in real time and automatically remove non-conforming products.

Process optimization

Segmented heat sealing and cooling: The heat sealing process is divided into three stages: preheating, main sealing, and cooling to reduce local deformation.

Negative pressure adsorption molding: Add a negative pressure adsorption device in the molding area to ensure that the membrane material closely adheres to the mold.

Personnel training

Operation training: Regularly train operators to master the skills of equipment adjustment, parameter setting and troubleshooting.

Quality awareness: Strengthen the quality awareness of operators to ensure that operations are carried out in accordance with standards.

Summary

The improvement of the packaging flatness of the transparent film three-dimensional packaging machine requires comprehensive optimization from multiple aspects such as film materials, equipment, processes, and monitoring. By choosing high-stiffness film materials, optimizing tension and heat sealing processes, upgrading equipment control systems, and strengthening daily maintenance and data analysis, the flatness of packaging can be significantly improved. Operators must strictly abide by the operating procedures, promptly identify and solve problems, and continuously improve packaging quality in combination with technological upgrades.