Foil seal prior to and after inductive bonding
View our capsealing video
Read our article in Process Heating Magazine
Heating pre-assembled plastic tube and cap
Sealing aluminum foil cap to plastic bottle
Cap Sealing 3.5” Lotion Container
Tamper-evident cap sealing
Cap sealing; shampoo container
- Overview
- Using Induction
- The Seal
The food and medical industries require high-speed hermetic sealing between the cap and the container. Induction heating with Ameritherm equipment provides the following benefits for cap sealing applications:
- high reliability seals
- easy integration into production lines
- high process speeds
A cap- to-container seal is made with the aid of a laminated disc composed of a wax layer, aluminum layer, and a polyethylene (PE) layer (illustration).
The aluminum layer acts as a susceptor, heating to about 125-150°C in the electromagnetic field produced by the induction coil. It then heats the wax and PE layer sufficiently to produce a hermetic seal between the cap and container. Heating times are in the order of 100 milliseconds, supporting a high-speed automated process.
Typical RF power supplies for cap sealing range from 1 to 20 kW, depending on the parts and application requirements.
A cap seal liner is comprised of a multi-layered board:
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the first and thickest layer of material is the board re-seal
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next is the layer of wax used to hold the aluminium foil to the board re-seal
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next is the aluminium foil
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last is a heat seal film compatible with the type of container to be sealed