No. The heating is highly selective. Only the conductive aluminum foil layer gets hot, and only for milliseconds. The container (plastic/glass) and product remain at or near ambient temperature.

Induction sealing is a non-contact method using electromagnetic fields. Traditional heat sealing uses direct contact with a hot platen or hot air. Induction is faster, more consistent, and doesn’t heat the container.

Primarily plastic (HDPE, LDPE, PET, PP) and glass containers. The container must be non-metallic to allow the magnetic field to pass through. The cap must be plastic or aluminum (requiring a special magnetic foil liner).

Generally, no. A full metal container or lid will shield the electromagnetic field, preventing the foil from heating. Exception: Special magnetic foil liners can be used with aluminum caps (common in liquor/wine), as the field induces heat in the foil’s magnetic layer through the cap.

Liquids, powders, granules, and solids across industries: food, beverage, pharmaceutical, chemical, cosmetic, and automotive. It is not suitable for products in pressurized aerosol cans.

Yes, but the sealing surface (the bottle’s mouth) must be flat and even. The induction coil can be custom-shaped (oval, rectangular) to match the cap’s footprint. Very uneven rims may require foam-backed foils.

No. Liners vary by material layers (pulp, wax, aluminum, polymer), barrier properties, and sealant type. The liner must be chosen to match your container material, cap type, and product characteristics (e.g., acidity, oil content).

It’s a specialty liner where the entire foil disk comes off cleanly in one piece when the cap is unscrewed, leaving no residue on the bottle rim. Common in pharmaceutical and medical applications for sterile access.

Common reasons:

Incorrect Power/Time: Insufficient heat or dwell time.

Contaminated Rim: Product residue, dust, or moisture on the bottle’s sealing surface.

Mismatched Foil: The polymer sealant layer is incompatible with your container material.

Insufficient Pressure: The cap wasn’t torqued properly during sealing.

Warped Rim or Cap: Uneven sealing surface.

Air-cooled units use internal fans and are suitable for lower to medium production speeds. Water-cooled units use a closed-loop coolant system to dissipate heat from the sealing coil and generator, allowing for continuous, high-speed operation without overheating.

Conduct a peel test (the foil should tear, leaving a bonded layer on the rim) or a burst/dome test (applying air pressure to see if the seal holds). Visual inspection should show a smooth, wrinkle-free foil bond.

This indicates excessive heat. Reduce the power setting or seal time. It can also occur if the foil is misaligned or if there’s no bottle present during activation (“air firing”).

Yes, but it requires changeover. You typically need to:Adjust the conveyor guides.

Change the induction coil to match the new cap size/shape.

Recalibrate the power and time settings.

Adjust the sealing head height.

The field is strong but very localized to the immediate area around the sealing coil. Modern machines are shielded to meet international EMF safety standards (like ICNIRP guidelines). Operators should avoid placing hands or metallic objects near the active coil.

Change the induction coil to match the new cap size/shape.

Recalibrate the power and time settings.

Adjust the sealing head height.