Heat sealing of TPU massage airbags

To address the heat-sealing requirements of TPU massage airbags, combining high-frequency welding technology with the properties of medical-grade materials, the following are key solutions:

I. Material Selection and Pretreatment
* TPU Film Selection: Medical-grade TPU film with a Shore hardness of 85A-95A is recommended. Its elongation at break can reach 400%-600%, resilience is close to 100%, and it can withstand more than 100,000 inflation/deflation cycles.
* Surface Treatment: Plasma treatment (300W power, 30 seconds) is required before welding to increase surface energy and ensure weld strength.

II. Heat-Sealing Process Parameters

* High-Frequency Welding:

Frequency: 27.12MHz
Mold Temperature: 80-100℃
Welding Pressure: 0.3-0.5MPa
Holding Time: 3-5 seconds

* Ultrasonic Welding: Suitable for small-sized airbags. Parameters: 20kHz frequency, 50-70μm amplitude, holding time 2-3 seconds.

III. Automated Integration Solution
Rotary Heat Sealing Machine: The four-station rotary design enables continuous operation, with a single cycle time of 8-12 seconds, increasing efficiency by 60%.

Quality Inspection: Integrated with an airtightness tester (accuracy 0.01ml/min) and a tensile testing machine (ASTM D1876 standard), achieving 100% online inspection.

IV. Quality Control Standards

Airtightness Test: Must pass a 0.5MPa pressure holding test (holding time ≥30 seconds), with a leakage rate <5ml/min.

Weld Strength: Peel strength must be ≥8N/cm; a double welding process is recommended to improve compressive strength.

Note: In actual production, it is recommended to conduct small-batch trial production first, focusing on verifying the balance between weld strength and sealing performance. Medical-grade products require additional verification of biocompatibility indicators.