How Does a Heat Sealer Work?

Impulse heat sealers use heated sealing wires that are triggered when the sealing bar is pressed close. The sealing bar is often made of a silicone seal pad able to withstand direct heat contact. The sealing bar pushes on the wire and film to melt and mend the material forming a seal.

Heat sealers can be used with foil, poly-coated Kraft paper bags, and many different plastic materials. Sealers come in varying sizes and designs. Heat sealers with a flat sealing wire make stronger, thicker seals. Round wire sealers make thinner, less visible seals. Below is a detailed description of images explaining how a heat sealer works.

Sealing Bar Closes With Film Between

As explained above, the sealing bar is made of a heat resistant material designed to come into direct contact with the heated metal wire. The film is placed over the sealing wire, and the sealing bar is closed. Springs on the sealing bar allow the user to apply pressure to the film.

The Heat Element is Triggered

As the sealing bar is closed, a microswitch is enacted an electrical current is sent to the end connector posts. End posts heat the sealing wire with electrical current. The microswitch also triggers the sealing light to indicate sealing has begun.

Sealing Begins

When the microswitch engages, the sealing wire is quickly heated. The heat from the wire melts the material being used. The pressure from the sealing bar being pressed down mends the two sides together, creating a seal.

Sealing Completion

Upon completion, the seal light will turn off, indicating the seal is complete. A round wire sealer will seal off the film and cut excess length after the seal is complete. A flat wire sealer will create a thicker, wider seal and not cut the excess material.

Finished Product

The finished product should have a smooth, straight seal line with no wrinkles. The right heat sealer with proper seals can increase product longevity and form airtight seals.