Key Takeaways
An L-bar sealer and a side sealer both wrap products in shrink film and pass them through a shrink tunnel, but they seal differently. An L-bar sealer closes two sides of the pack in one stroke inside a fixed sealing frame, so it suits products of consistent size, placed one at a time, at low to medium volumes, for a lower investment. A side sealer seals continuously down one side as products move along a conveyor, so product length is not limited and the line keeps running, which suits long products and continuous, higher-volume production. If your products fit the frame and volumes are moderate, choose the L-bar; if they are long or arrive on a conveyor, choose the side sealer.
Compare the L-bar sealer and the side bar sealer, with specifications and video, on the shrink wrap machines page.
The difference is how each machine seals the film. An L-bar sealer uses an L-shaped heated bar that seals and trims two sides of the pack in one stroke, with the product sitting inside centre-folded film; the pack then goes through a shrink tunnel. Because the bar closes around each pack, the product must fit inside the sealing frame, and the machine stops briefly for every pack. A side sealer seals continuously along one side of the film while products travel on a conveyor, with a cross seal between packs, so the line never stops and product length is not limited by a frame.
The table compares the two machines feature by feature.
| Feature | L-bar sealer | Side sealer |
|---|---|---|
| Sealing method | L-shaped bar seals two sides in one stroke | Continuous seal along one side, plus a cross seal |
| Operating mode | Intermittent: stops for each pack | Continuous: packs keep moving |
| Product length | Limited by the sealing frame | Unlimited |
| Product sizes | Consistent sizes that fit the frame | A wide range of sizes and lengths |
| How products arrive | Placed by hand, or by an automatic infeed | On a conveyor, straight from the line |
| Rated speed | Up to 25 packs/min; well below that when loaded by hand | Up to 25 packs/min in continuous flow, set by product spacing |
| Automation | Manual, semi-automatic or automatic | Mostly automatic |
| Film | Centre-fold POF | Centre-fold POF or LDPE |
| Best for | Small to medium production | Medium to high volume, continuous lines |
| Typical industries | Retail, food, cosmetics, printed goods | Manufacturing, building materials, FMCG, logistics |
| Energy use | Lower | Higher, because it runs continuously |
| Initial investment | Lower | Higher |
| Scalability | Moderate | Scales with conveyor and line integration |
On our range both are rated at up to 25 packs a minute, so the difference is how much of that rating each achieves in practice. A side sealer runs continuously, so on a conveyor-fed line its real output is set by how closely products are spaced, and it holds its rate shift after shift. An L-bar sealer stops for every pack, and when products are placed by hand the operator sets the pace, so a manual or semi-automatic L-bar runs well below its rating. An automatic L-bar with an infeed conveyor closes much of that gap.
An L-bar sealer suits products of consistent size that fit its frame: boxes, cosmetics, books, electronics, bakery products, pharmaceutical cartons, gift packs and small multipacks. A side sealer suits long, flat or irregular products and anything that exceeds an L-bar frame: furniture components, doors, printed materials, flat-packed items, long cartons, curtain rails, pipes and profiles. Bottle and can multipacks are neither machine’s job; they run on a sleeve sealer and shrink tunnel. Long industrial parts are covered in how industrial parts are shrink wrapped.
An L-bar sealer needs a lower initial investment and uses less energy, which makes it the economical choice for lower volumes and smaller businesses. A side sealer costs more to buy and draws more power because it runs continuously, but on a busy line it earns that back through sustained output, less hand labour and less film waste. The shrink wrap machine cost guide explains what moves the figure.
Choose an L-bar sealer if your products fit its frame, arrive one at a time and run at low to medium volumes; choose a side sealer if they are long or irregular, arrive on a conveyor or run continuously. Both are paired with a matched shrink tunnel. Send us your largest product, your volume and how products reach the machine, and we will specify it. For the wider decision, see how to choose a shrink wrap machine, or compare all four machines on the shrink wrap machines page.
Only products that fit inside its sealing frame. Anything longer than the frame needs a side sealer, which seals continuously so there is no length limit.
Yes. A side sealer seals the film around the product; a matched shrink tunnel then shrinks it tight. The same is true of an L-bar sealer.
Yes, and many businesses do. An L-bar sealer suits lower volumes; an automatic L-bar with an infeed conveyor raises output; and a side sealer takes over when products get longer or the line needs to run continuously.
Send us your largest product, your volume and how products reach the machine, and we will specify the sealer and tunnel that suit it, with installation by our own technicians, a one-year warranty, CE marking on request and spares held in Johannesburg. You can also send samples and we will trial-wrap them at our Johannesburg showroom before you buy.
