<img height="1" width="1" style="display:none" src="https://www.facebook.com/tr?id=216539877280951&ev=PageView&noscript=1" /> Impulse Sealers: What Are They & How Do They Work? - Dymapak

Candies, chips, food, popcorn, and cereals. What do they have in common? They’re stored in poly bags on supermarket shelves.

These bags are great for packaging since they are lightweight, making them cost-effective and sustainable during shipping. They are also heat sealed to keep them airtight and prevent humidity and other elements from interfering with the product. The device that helps to heat seal packaging is an impulse sealer.

So, what is an impulse sealer? How does it work? Why do companies prefer it over other heat sealers?


What Is an Impulse Sealer?

An impulse sealer is a powered device that seals various types of plastic packaging, primarily flexible packaging like poly bags and stand up pouches.

It utilizes an electrical impulse to heat a metal wire, melting a layer of plastic into another. The resulting permanent seal only breaks by cutting it open. Anyone who uses the tool requires the proper training.

The five impulse sealer types are tabletop, double impulse, automatic, attached cutter, and foot-operated. The tabletop type is operated by hand and resembles a stapler, with a jaw or lever pressed down.

On the other hand, the foot-operated type is mounted on a movable stand and is designed for higher volume projects.

What about double impulse sealers, you ask?

They have dual sealing bars that connect thick plastic and are employed in heavy-duty operations, like machinery components or automotive parts.

Impulse sealers that have an attached cutter will slice the plastic after sealing. The impulse sealer is perfect for plastic tubing, which needs both packaging ends to close to form a sealed bag.

Automatic sealers live up to the name. They automatically seal materials without a person operating the device. You can even program them for different sealing times, temperatures, and materials.


Are Impulse Sealers and Heat Sealers the Same?

No, impulse sealers and heat sealers are not the same. A heat sealer is used for sealing packaging, products, and other thermoplastic materials with heat. In contrast, an impulse sealer is a device that serves the same function with subtle differences.

Impulse sealers need no warm-up time and apply an electrical pulse to the sealing zone before immediately cooling it. Also, they only use power after the jaw lowers. On that account, it’s perfect for sealing everyday poly bags, bubble packs, mylar, and Tyvek.

Impulse sealers are preferred for their safety because heat is only generated when the jaws contact each other. Therefore, you can’t burn yourself when you touch the jaws, and even when some residual heat remains in them for some time, the temperatures are never high enough to be hazardous.

An impulse sealer gives you complete control over the seal wire’s temperature while the device seals the material. And because the sealing element is briefly energized, there is lower power consumption and a decrease in operational costs.

On the contrary, heat sealers have consistent heat on both jaws and use power as long as the device is turned on. Therefore, heat sealers have better heat penetration for sealing thicker materials, like kraft paper, coated aluminum foils, gusseted bags, and cellophane.

Most modern heat sealers have protective barriers for reducing the risk of burn injuries. While the impulse sealer’s regular heating and cooling cycles can destroy the heating element without a temperature controller, a heat sealer reduces the constant expansion and contraction of the material to avoid stress and deformation.


What Can You Use an Impulse Sealer For?

Impulse sealers are used for sealing packages and products before being shipped to the customers. Here are some businesses that require the device to run:

  • Component suppliers and hardware stores
  • Part manufacturers and automotive stores
  • Component suppliers and electronic stores
  • Food manufacturers, candy stores, and tea retailers
  • Other industries that manufacture components and physical products

Why Do Companies Heat-Seal Packages?

Food companies use flexible packaging because it can be heat-sealed and keep food fresher and longer.

Barrier bags and stand-up pouches are created using numerous laminated layers, leading to a single structure that stays upright on shelves while keeping their pliable shape and lighter weight. Heat sealers are the key to creating this packaging formation.

A heat sealer joins the layers together, forming an airtight, tear-resistant seal and keeping the food intact from external elements.

Hand-held heat sealers are perfect for small businesses trying out stand-up pouches since they’re handy and easy for this packaging type. But advanced heat sealers are required for larger businesses that need to heat seal thousands of packaging.

How Impulse Sealers Work

The sealing bar comprises a heat-resistant material made to directly contact the heated metal wire. The packaging is placed over the metal wire before closing the sealing bar. The device has springs that allow the user to apply pressure to the material.

Pressure from the sealing arm holds the packaging in place. If using a hand-held impulse sealer, the user applies the pressure.


How Impulse Sealers Heat Up

The closing of the sealing bar triggers a microswitch that turns on the electric current to the connector posts, which then heats the sealing wire. The microswitch will also depend on the sealing light to indicate sealing has started. Low heat levels allow tape and wire to last longer.


Impulse Sealers Melt the Packaging Together

The heat generated by the sealing wire melts the packaging material. Then the pressure from the sealing bars helps to mend the two sides of the material to form a seal.

Once done, the seal light turns off, indicating completion of the heat-sealing process. A round wire sealer seals off the packaging and cuts excess length. On the other hand, a flat wire sealer creates a thicker, wider seal and doesn’t cut the extra material.


After Sealing, a Package Is Ready To Ship

After sealing, the packaging has a straight, smooth seal line without wrinkles. A good heat sealer will create airtight seals that increase the shelf-life of your product.

Now you can ship your products to your consumers and distributors without worrying the products will go bad or get damaged in transit.


Are Impulse Sealers Safe?

Impulse sealers only heat up when the jaw is pressed on the material, generating an electric current that heats the wire.

When the packaging seals and the jaw releases it, the electric current stops flowing, the heating halts, and the device will start to cool down quickly. Because the device is not heating when not in use, it’s safer than the constant heat sealer.

The heat generated by the impulse sealer is also low and not enough to cause serious harm to the user.



Sealing your packaging properly is crucial to the safety and shelf-life of your products. This makes impulse sealers important to the packaging process of your business as they will seal the packaging airtight and prevent external elements from contaminating your goods.

While impulse sealers heat only when the jaw is in contact with the packaging, constant heat sealers are constantly hot, provided the device is on. This makes impulse sealers safer but only applicable to light materials, while continuous heat sealers are suitable for thick materials.

You can use an impulse sealer to heat your poly bags regardless of the products you want to ship.

Our packaging solutions will come in handy as you look to promote your products’ sustainability and safety. Contact us at Dymapak today!



What is Heat Sealing? – Definition from Corrosionpedia | Corrosionpedia

What is a Thermoplastic? (Definition and Examples) | TWI

Investigation of the effect of sealer use on the heat generated at the external root surface during root canal obturation using warm vertical compaction technique with System B heat source | NIH