An inflatable closure is a pressure seal first. It is folded, packed and inflated repeatedly, and it has to hold air as well as keep water out — which puts it in the airtight category rather than the watertight one.
What to specify
- Sealing strength: airtight builds are published with a 60 kPa sealing pressure test (#10 resin, circular).
- Derail recovery: the self-healing airtight zipper resets automatically after derailing, which matters on inflatables and rescue equipment where failure is not an option.
- Closed-loop openings: where the port is not a straight line, the circular airtight zipper gives 360-degree sealing.
- Assembly: HF welding suits the TPU and PVC panels used on inflatables.
Published values to check against your project
| Parameter | Published value |
|---|---|
| Seal strength (#10 resin, circular) | 60 kPa |
| Seal strength (#5 resin, self-healing) | 30 kPa |
| Tensile strength (#10 resin, circular) | 1100 N/5 cm |
| Heat resistance (TPU) | -30°C ~ 70°C |
| Durability | 3000+ cycles |
