How induction sealing works
- The cap is supplied with an induction liner: typically a pulp or foam backing, wax, aluminium foil and a heat-seal polymer.
- The bottle is capped at normal torque.
- It passes under the induction head; the field heats the aluminium foil.
- The polymer melts and bonds to the rim; the wax melts into the backing (two-piece liners) leaving a foil seal on the bottle and a reseal liner in the cap.
Why use induction seals
- Leak protection during transport, especially for liquids and powders.
- Tamper evidence (“sealed for your protection”).
- Freshness and aroma protection for food and supplements.
Our induction foil sealer
The Water-cooled induction foil sealer is a water-cooled conveyor sealer for 8,000–12,000 bottles per hour, used on pharmaceutical, supplement, food and chemical bottles. It sits after the capper — for example after a CG120 high-speed capping machine.
Water-cooled vs air-cooled, handheld vs conveyor
| Type | Use |
|---|---|
| Handheld / portable induction sealer | Very small batches, lab or start-up |
| Air-cooled conveyor sealer | Low to medium speeds |
| Water-cooled conveyor sealer | Continuous production and higher speeds |
Getting a good seal
- Correct cap torque — too loose and the foil does not press on the rim. See cap torque.
- Liner matched to bottle material (PET, HDPE, PP, glass).
- Power and conveyor speed set by test; inspect for weak, wrinkled or burnt seals.
- Flat, clean bottle rims.
Need a sealer for your line? Send bottle, cap and speed.
Questions and answers
What is an induction cap sealer?
A machine that bonds a foil liner inside a cap to the bottle rim using electromagnetic induction heating, after the bottle has been capped.
Does induction sealing work on glass bottles?
Yes, with a liner designed for glass. Liners are chosen to match PET, HDPE, PP or glass rims.
How fast is a conveyor induction sealer?
Our water-cooled sealer lists 8,000–12,000 bottles per hour.
Why is my induction seal not sticking?
Common causes are low cap torque, wrong liner for the bottle material, too little power or too high conveyor speed, or a damaged rim.
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