In the modern world of eCommerce, packaging cannot just be an afterthought. Ensuring a tight, fitted, and secure compartment to hold and transport goods is essential. This is because a plastic wrapping or bag is often the first line of defense for the product. In this context, a plastic bag sealer can be of great help.
To put it simply, bag sealers apply heat to plastic in order to melt the material and create a tight, strong seal. The device has two arms, also called clamps, which can be closed on the desired spot to heat the area. As soon as the bond is created, the excess plastic can be torn off to the sides. In this step, it’s important to pull on the excess, not the bag itself. This is because the direction of the pull will determine how strong or thick the seal is in that specific area. The side on which the plastic is pulled will be stretched and have a thinner, more fragile seal. After applying the heat, it’s also important to let the package cool a bit before stretching it, as the material will still be malleable shortly after being used in the heat sealer.
Not all plastics respond the same to high temperatures. The ones used in heat sealer machines are called thermoplastic polymers. Some examples include polyethylene (PE), polypropylene (PP), polystyrene (PS), and polyvinyl chloride (PVC). These plastics are commonly found in plastic bags and don't require extreme temperatures to create a seal. Moreover, depending on the type of sealer, nylon, foil, mylar, or coated sheets can also be used.
The different plastic bag heat sealers can be classified according to their mechanism or intended use. Concerning the latter, users can find either handheld or stationary models. The first type is ideal for small bags and quick sealings, being commonly found in warehouses. They resemble a paper clipper and can be used on the go. That being said, their ability to generate heat is limited, which means they won’t be enough to seal thicker materials nor are capable of creating as strong a seal as their fixed counterparts. Stationary sealers, on the other hand, are bulkier, ideal for heavy-duty industrial sealing, and require more training to be operated safely.
When it comes to the mechanism, impulse and direct heat sealers are the main options. As the name suggests, impulse sealers produce a surge of energy capable of swiftly bonding the two sides of the polymer to create a seal. This way, users don’t have to worry about burning themselves, as the heat is generated locally, for a short moment, and in a controlled manner. However, this also means that these devices won’t be able to handle tougher materials. Direct heat sealers, on the other hand, generate high temperatures around the clock, as long as they are turned on. This gives them a higher heat penetration, making them ideal for sealing thicker materials.