Induction Sealing Glossary of Terms - What to Know
Our industry has some unique terms that some users may be unfamiliar with.
Channel (Tunnel) Coil
A coil design which is directed toward the various child resistant and dispenser type caps which would be very difficult to seal using a convention flat coil system. The sealing coil allows for the container neck and cap to pass through the electromagnetic field inside the tunnel, providing uniform heating and sealing to the container.
Coil
(see sealing head, tunnel coil or channel coil, universal coil or hand held coil) The coil, or sealing head, is the primary souce of electromagnetic current necessary to heat the foil liner.
Crooked or Cocked-Cap
Where the cap is not properly threaded (screwed) onto the bottle leaving an angled cap. This will prevent a good seal or bond if the liner is not touching the bottle’s surface or landing area.
Electromagnetic Field
Magnetism developed by a current of electricity.
Direct Seal
A sealing solution for applying a foil barrier or protective seal when a cap is not required or when it’s advantageous to seal the container before applying a cap.
Hand-Held Coil
Sealing head for manual systems.
Hand-Held Sealer
Term used for lower volume manual sealing systems.
Induction Sealing
Otherwise known as cap sealing, is the phenomenon where electrical energy is transferred from one device to another through the air by an electromagnetic field. Induction sealing is a non-contact method of heating a metallic disk (foil liner or innerseal) to hermetically seal the top of plastic and glass containers. This sealing process takes place after the container has been filled and capped.
Inverter (or Power Supply)
Is the electrical unit that supplies high voltage, high frequency energy to the sealing coil.
Kilowatt
The only real measurable means of determining the exact power requirements necessary to run your line at the production output speeds you require.
Line Speed
Conveyor speed in feet per minute or production output gauged in desired bottles/containers per minute.
Loose Cap
The cap was not torqued completely. Loose caps may prevent the foil innerseal from actually bonding to the top of the bottle. They must be torqued properly.
Missing Foil
Occurs when there is no liner inserted inside the cap initially, or the lined cap never reached the bottle. There are detection systems available to monitor for missing foil.
Overseal
Means too much power is being utilized or the dwell time (sealing speed) needs to be decreased on conveyor system. Oversealing causes damage to the seal layer or protective barriers that can result in faulty seals even weeks after the initial sealing process.
Sealing Head
(see Coil, Hand held, Channel, Tunnel or Universal coil) The sealing head, or coil, is the primary souce of electromagnetic current necessary to heat the foil liner.
Sealing Surface
The land area (lip) where the foil liner bonds to the container.
Tunnel (Channel) Coil
A coil design which is directed toward the various child resistant and dispenser type caps which would be very difficult to seal using a convention flat coil system. The sealing coil allows for the container neck and cap to pass through the electromagnetic field inside the tunnel, providing uniform heating and sealing to the container.
Universal Coil
A special sealing coil available exclusively from Pillar that permits sealing of a wide range of cap sizes without changing coil sizes. It works by angling the coil with respect to the conveyor path. Whatever the cap size, the entire cap will pass through the electromagnetic field.
Water-Cooled
Older technology that required water to cool the sealing head.
Waterless (Air-Cooled)
The most efficient, cost-effective means of cooling the inverter and sealing coil.