Automatic High-Frequency Seamless Welding Machine for TPU Materials

Core Functions and Process Principles
High-Frequency Electromagnetic Field Heating Technology
The device utilizes a 27.12 MHz high-frequency electromagnetic field to induce molecular polarization and frictional heating within the TPU material, enabling rapid fusion welding. Key advantages include:
Heating Speed: TPU material reaches a molten state within 0.5–3 seconds under the high-frequency electric field, representing an 80% increase in efficiency compared to traditional hot-air welding.
Welding Quality: Weld depth reaches 60%–80% of the material thickness; peel strength is ≥50 N/15 mm (ISO 6134 standard); and airtightness testing shows a pressure drop of ≤5% over 24 hours (at 20 kPa overpressure).
Material Compatibility: Compatible with polar plastics such as TPU, PVC, and EVA; supports customized processing for material thicknesses ranging from 0.1 mm to 4 mm.
Automated Process Design
Automatic Feeding System: A rotary work platform (featuring 4–8 mold blocks arranged in a circle) operates in coordination with a robotic arm to sequence mold blocks into the heat-sealing station, eliminating the need for manual feeding. For example, a patented version of this device uses a motor-driven rotary shaft to rotate the platform, automatically positioning mold blocks beneath the heat-sealing unit.
Waste Recovery Module: Integrates a TPU waste shredder (e.g., Hongshengtai brand, 8151 W power) capable of grinding offcuts into 0.5–2 mm granules; achieves a recovery rate of over 95%, supporting subsequent re-granulation and production.
Finished Product Output: Upon completion of heat sealing, the device automatically unloads products using an ejection assembly (pneumatic cylinder-driven ejector rod) or an unloading robotic arm, followed by sorting and packaging via a conveyor belt.
II. Key Technological Innovations
Rotary Work Platform Design
Structural Optimization: Mold blocks are evenly arranged around the work platform, creating distinct zones for heat sealing, loading/unloading, and transition, thereby enabling parallel multi-stage processing. An 8-station design reduces the single-cycle production time to 8–12 seconds, boosting efficiency by 300% compared to traditional single-station equipment.
Transmission Precision: Employs a bevel gear drive mechanism (1:1 gear ratio) to ensure rotary shaft positioning accuracy within ±0.05 mm, meeting the requirements for high-precision welding. High-Frequency Welding Process Control
Parameter Optimization: Adjustable output power (5–8 kW), pressure (0.2–0.5 MPa), and welding time (3–5 seconds); closed-loop control of temperature, pressure, and time is achieved via a PLC system. For example, Puxiong’s production line for surgical robot TPU protective covers utilizes this technology, reducing the welding defect rate from 3% to 0.2%.
Safety Protection: Equipped with a spark suppression circuit (response time ≤0.1 ms) and overload protection devices to prevent mold damage and extend equipment service life to over 10 years.
Waste Recovery and Recycling
Integrated Shredding and Granulation: After processing in a shredder, waste material undergoes water-strand pelletizing via a single-screw extruder (e.g., Wright Brothers brand, 280 kW power) to produce recycled TPU granules; these can be directly used to manufacture products with lower performance requirements, reducing raw material costs by 15%–20%.
Environmental Compliance: TPU material releases no toxic gases during combustion, and the recycling process complies with RoHS standards, helping enterprises achieve ISO 14001 environmental management system certification.