Sealing

Induction sealing is the process of bonding thermoplastic materials by induction heating. This involves controlled heating an electrically conducting object (usually aluminum foil) by electromagnetic induction, through heat generated in the object by eddy currents.
Induction sealing is used in many types of manufacturing. In packaging it is used for package fabrication such as forming tubes from flexible materials, attaching plastic closures to package forms, etc. Probably the most common use of induction sealing is cap sealing, a non-contact method of heating an inner seal
to hermetically seal the top of plastic and glass containers. This sealing process takes place after the container has been filled and capped.

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