Heat sealers are essential for many businesses and industries, which are often used to package medical, manufacturing, and food products. With so many sealers to choose from though, it can be hard to find the right one for you.

There are different designs to meet different requirements, such as sealing to certain Clean Room Standards, but there are ultimately two main categories of bag sealer machines: rotary and impulse.

We cover how rotary and impulse heat sealers work, as well as the advantages and disadvantages of each:

Rotary and Impulse Sealers

What are Impulse Heat Sealers?

Impulse heat-sealing machines (also referred to as jaw, clamp, or manual heat sealers) are the most popular type of bag sealer and delivers heat in a short interval to weld two poly materials together. They often come in the form of a hand sealing machine and are used on packaging that contains identical thermos-plastic films on all sides – usually a polythene material, but it can also seal thinner gauge laminate materials too.

Rotary and Impulse Sealers: How it works

An impulse heat sealer works by using an electric current to heat up the sealing element for a short period of time. The user simply places the bag onto the heated bar and pulls down the clamp. After a few seconds the clamp is lifted and the pouch is sealed.


  • The sporadic use of the electric current results in lower power consumption, reducing operation costs.
  • Safety: the high heat needed to complete the seal is only present when the clamp is down, making it very hard to burn yourself. Even residual heat that can last for a couple of hours never reaches a temperature hot enough to be dangerous, reducing the risk of damage or injury in-between cycles.
  • The low voltage heating contains wires that have almost no heat up time, allowing you to reach the necessary sealing temperature in seconds.


. the heat must be applied manually, raising the risk of compromising sterility if the pouch is not held within the heated bars for long enough. Other sealers like a continuous heat sealer are more reliable in regards to forming airtight seals.

What is a Rotary Heat Sealer?

A rotary heat sealer is normally used for laminated poly material comprised of multiple layers of thermoplastic film. These can have various mechanical properties and melting points depending on the construction, but laminate foils, coated papers, cellophane, and polypropylene films will usually require a constant seal.

A rotary band sealer (or constant heat sealer) welds the tops of bagged products that move along a conveyor and are available in either horizontal or vertical models. A horizontal band sealer is used for sealing products laid flat, whereas a vertical rotary band sealer fuses upright bags.

How it works

Ideal for any mid to high volume packaging environment, the bag is fed through the left or right side of the machine and a motor pulls it through automatically.  As the bag moves along, the sealer applies pressure and heat to seal the bag. It always applies the same amount of pressure, time, and heat between the heated bars, producing a constant quality of seal.


  • All sectors can benefit from the high-speed sealing and consistent seal cycles of rotary heat sealing.
  • Unlike impulse sealing (where the temperature rises and falls up quickly), continuous band sealing provides a highly controlled temperature, making it more adaptable to some poly-coated and thermoplastic materials.


  • The sealing bars are continuously held at the prescribed sealing temperature at all times and will remain hot, creating a greater risk of injuries in-between cycle times. However, they have protective barriers to reduce and eliminate burns from occurring.

For Reliable Rotary and Impulse Sealer Machines, Browse Valdamark’s Diverse Range Today 

Here at Valdamark, we offer a complete range of both rotary heat sealers and impulse bag sealers.

For more information on our wide range of heat sealer machines, don’t hesitate to get in touch today. We’re more than happy to offer advice and support to help you choose the right bag sealer for your business’s needs.