What impact does heat sealing technology have on the performance of liquid storage bags?

The impact of heat-sealing technology on the performance of liquid storage bags is primarily reflected in three aspects: sealing integrity, material compatibility, and process stability. Below is a detailed analysis:

1. Critical Impact on Sealing Performance

Heat-Seal Strength and Sealing Integrity

The combination of heat-sealing temperature, time, and pressure directly affects weld strength. Insufficient temperature may result in poor sealing, while excessive temperature can damage the membrane material.
Process parameters must be optimized through orthogonal testing; for instance, temperature gradient tests can mitigate leakage risks.

Sealing Inspection Standards

Pressure decay methods (e.g., Leak-SUS testers) are employed to detect sealing integrity, requiring a precision of 1 Pa to meet GMP standards.

2. Material Compatibility and Process Control

Adaptability to Membrane Materials

Different materials (e.g., PVC, TPU, ETFE) require specific heat-sealing technologies:

• High-frequency welding is suitable for polar materials (PVC/TPU), while ultrasonic welding is more appropriate for non-polar materials (PP/PE).
• Variations in material thickness (e.g., ±30%) must be addressed through dynamic pressure compensation technology.

Process Stability

Excessive or insufficient equipment operating speeds can lead to sealing defects, necessitating periodic validation of process parameters.
Mold design must account for thermal conductivity (e.g., beryllium copper material) and incorporate rounded edges to minimize material damage.

3. Industry Applications and Quality Control

Biopharmaceutical Field

3D liquid storage bags must undergo gamma irradiation sterilization (25-40 kGy), and the heat-sealing process must ensure sealing integrity under -80°C freeze-thaw cycles.

Medical Device Packaging

Peel strength of seals must meet ≥1.5 N/15mm (YY/T 0681.5 standard) to prevent failure of the physical barrier during transportation.

4. Technological Development Trends

• Intelligent Control: PID temperature control technology (±0.2°C accuracy) and adaptive pressure systems enhance sealing consistency.
• Multi-Material Compatibility: For instance, PuXiong heat-sealing machines support dozens of material-specific sealing profiles, enabling one-click parameter switching.