A bag heat sealer is a powder filling machine used to help form a bag, using heat to melt the sides together. Sealing things in their packaging is not only vital to protecting them and keeping them safe in transit, but also makes packaging. Particularly, clear poly bags. And to make that happen, you can use a simple bag heat sealer to close up the open end of a bag – you can even trim the ‘spare’ off to make for an even more professional job.

What is a bag heat sealer?
A plastic bag heat sealer is a simple heater that, when pressed and applied to a thermoplastic bag, seals the bag together using a combination of pressure and melting. The two plastic parts are brought together and pressed against one another and heated. This melts the plastic, which co-mingles and, as it cools, sets into a single plastic seam.

A plastic bag heat sealer essentially welds plastic togethe
It is akin to welding, but with plastic. Once cooled the join is essentially one piece of solid, even plastic, contiguous to the rest of the two pieces joined together. In short, it is a water-tight sealed weld between the two.
It can be used to join together two pieces of the same or two similar thermoplastics, such as Polythene of different grades. It Is most commonly found in packaging where it can form a water and dust-tight seal on a bag of pretty much any size.
They typically use a heated element or bar, often covered by a protective Teflon guard, so that the melting plastic doesn’t stick to the element which is pressed onto the plastic at the point where the joint is needed. It takes only a few seconds to seal, but it is a precise process. Too little time and the joint won’t form, too much and the plastic will burn. So most heat sealers feature a light that comes on when the seal is done, or, on more sophisticated heat sealing machines – as we shall see – they lift off when ready.

There are different heat sealing bag devices available for auger filling machine . Small, portable/desktop devices for smaller items at low volume; automated devices for sealing many individual items; and continuous heat sealers that seal continually as the item/items run through them.

Some also come with cutters, so that once sealed any excess plastic can be simply trimmed off, or, in the case of continuous sealers, a continuous row of items can be cut individually once sealed.

That’s how they work, but what can they seal?

Can you use a heat sealer on polythene bags?
50 micron layflat tubing, lay-flat tubing is ideal for heat-sealing

You can use a heat sealer on a polythene bag. Most polythene bag heat sealers are used to seal poly bags. The polythene for heat-sealed packaging comes in several forms: it can be supplied as bags, which need just one end sealed; or it can come as a layflat tube, which is like an open ended bag that covers the items and needs then to be heat-sealed shut at both ends.

Low density polyethylene, from which most bags and layflat tubing are made, is ideal for heat sealing as it melts at around 160C. This is hot enough to melt together the two sides and cool enough for it to cool and seal quickly when the heat and pressure is removed.

An added benefit is that, as it cools, the polythene contracts and pulls the seal even tighter. This is one of the key advantages of heat sealers for poly bags.Layflat tubing and dispenser kit

Layflat tubing is available on rolls so that you can continuously package up goods at an industrial scale if needed. It allows the user to create the size of package they need, with the goods simply put inside, the tubing cut to length, then heat sealed. This is ideal if you have a variety of sized objects in your warehouse that need packaging.

125 micron black layflat tubing
It also comes in black, as well as clear and recycled polythene options, with black packaging being ideal for keeping goods not only protected from light when in storage or transit, but also keeping them confidential when sent through the post.