A Brief Description of High-frequency Welding Efficiency Optimization for Multi-layer Co-extruded TPU Calendered films

High-Frequency Welding of TPU Calendered Film is a process that utilizes a high-frequency electromagnetic field to generate internal molecular vibration within the material, producing heat for rapid fusion. This technique is characterized by fast welding speed, no need for third-party additives, and high weld strength. It is widely used in the manufacturing of TPU films, packaging bags, medical bags, air cushions, and other products.

I. Core Principle

High-frequency welding employs high-frequency voltage to create an alternating electromagnetic field between two layers of TPU material. This causes rapid molecular vibration and friction, generating heat until the melting temperature is reached. The layers are then fused under pressure using a mold. This process heats the material from within, achieving fusion in just seconds without requiring welding additives. The result is a unified structure capable of withstanding significant tensile forces.

II. Efficiency of High-Frequency Welding for TPU Calendered Film

1. Material Selection and Formulation Optimization

A layered design approach is adopted:

• The surface layer uses highly wear-resistant and UV-resistant TPU to enhance weather resistance.
• The middle layer employs high-elasticity, low-temperature flexible TPU to ensure flexibility.
• Functional layers incorporate barrier agents or conductive particles to achieve properties such as airtightness or electromagnetic shielding.

Additionally, blend modification technology improves biodegradability, while compatibilizers enhance interlayer adhesion, elevating film performance from the source.

2. Multi-Layer Co-Extrusion Calendering Process Optimization

Equipment and process parameters are upgraded, incorporating dynamic adjustment systems for precise thickness control. Gradient temperature control and speed ratio matching eliminate internal stress and improve film flatness. Online detection technology provides real-time data feedback, enabling automatic adjustment of process parameters, reducing manual intervention, and enhancing production stability.

3. High-Frequency Welding Process Optimization

Parameters of high-frequency heating equipment (e.g., frequency, power, time) are meticulously matched. Pneumatic pressure systems and silicone buffer pads are integrated to avoid welding marks and enhance strength. Welding structures are optimized to increase contact area and reduce leakage risks. Ultrasonic cleaning pretreatment is introduced to remove static electricity and dust from the film surface, further improving the yield rate of welding.

4. Full-Chain Synergistic Efficiency Improvement

An intelligent control system integrates raw material ratios, calendering parameters, and welding processes to achieve fully automated regulation throughout the production cycle. Advanced technologies and equipment (e.g., high-precision dies, integrated high-frequency machines) are adopted to shorten production cycles. Supply chain management is optimized to ensure stable raw material supply and minimize downtime due to material shortages.