Hey everyone, let’s cut to the chase: if you’re in packaging, you’ve probably stared at a plastic can (you know those handy resealable ones for snacks, drinks, or even pet food) and wondered—can the same machine that seals metal cans do the job? Or wait, do we, as can sealing machine suppliers, even recommend that? Let’s break this down, no stuffy jargon, just real answers from someone who’s spent years tuning these machines for small brands and big manufacturers alike. Can Sealing Machine
First, let’s get the basics straight. A lot of people mix up two types of “cans” these days: traditional metal cans (those steel or aluminum ones you grab soda from) and the newer hard plastic cans (often called “rigid plastic containers” or “PET cans”) that hit the market in the last decade. Metal can sealing machines work by crimping a metal end lid onto the rim of a metal can body—two pieces of the same material, so the metal-lip-and-lid crimp forms a super tight, airtight seal. Plastic, though, is a whole different beast.
Wait, does that mean you can just plug a metal can sealer into a plastic can and call it a day? Spoiler: no, not usually. But hold on—this isn’t a “plastic can = impossible” situation. It’s more like, not all plastic cans are made the same, and not all sealers are built for plastic. Let’s get into the science that makes this matter.
Plastic has way more give (plasticity) than metal. Metal, when you crimp it, stays rigid after the bend, so the seal stays consistent. Plastic? If you try to crimp it with a regular metal sealer’s metal rollers, you’re way more likely to either stretch the plastic rim too much (causing cracks that let air and moisture in) or not form a tight enough bond, because the plastic won’t hold the crimp’s shape. Also, plastic can lids—wait, most plastic cans don’t use metal lids anymore, right? They’re often plastic lids with a peelable foil layer, or sometimes tamper-evident plastic seals. That means the sealing process needs to bond two different materials: plastic to plastic, or plastic to foil, instead of metal to metal.
But here’s the thing we see every week at our shop: a ton of brands think plastic cans are “unsealable” because they tried a cheap off-the-shelf metal sealer and it failed. We’ve worked with craft snack companies that wanted to switch to plastic cans to cut weight and reduce scrap (way better for sustainability than metal, for small batches), and we’ve built modified sealers just for that. So let’s split this into two cases: can a standard can sealing machine seal plastic cans? Probably not. Can a custom or compatible machine, that’s built for plastic? Yes—if you do it right.
Let’s talk about the common mistakes people make. First, rim thickness. Metal can rims are usually around 0.2 to 0.3 mm thick, while PET plastic can rims are often 0.4 to 0.6 mm. If your sealer’s rollers are calibrated for metal’s thinner rim, they’ll clamp too hard on plastic, warping it. We see this all the time: a brand buys a secondhand metal sealer, slaps a plastic can on it, and ends up with lids that pop off on the shelf. That’s why calibration is non-negotiable for plastic.
Then there’s heat. A lot of plastic can sealing isn’t just mechanical crimping—it’s heat-assisted, to melt the foil or plastic lid layer so it bonds to the can’s rim. Metal sealers rarely use heat, because metal conducts heat too well and would burn the lid. But for plastic, heat is key. Our team adds induction heating elements to our sealers that let you adjust the temperature depending on what plastic you’re using (PET vs. HDPE, for example) and what seal you need: a peelable seal for snacks that need easy opening, or a hermetic seal for spices that need to stay fresh for a year. That’s a game-changer.
Wait, what about smaller, tabletop sealers? A lot of new small business owners ask us: “I just need to seal 50 cans a day—can a cheap tabletop sealer do plastic?” Yeah, but only if you get a tabletop model that’s made for dual-material use. We sell entry-level units that let you swap roller sets: one set for metal cans, another for plastic. It’s not like you have to buy a whole new machine if you dip your toes into plastic packaging. But skip the super basic $200 tabletop sealers—we’ve had customers come back with those, saying they seal 10 cans, then 11 leaks, 12 pops. The cheap ones don’t have the torque to handle plastic’s flexibility, and their calibration is off.
Another point: tamper-evident seals. A lot of plastic cans need a breakaway tab on the lid to show if someone opened it. Metal cans have that too, but plastic requires the sealer to make a clean break without cracking the can. We’ve tested dozens of plastic rim designs, and the best ones have a slightly grooved edge that the sealer’s roller can lock into, so the tab stays intact. If the rim doesn’t have that groove, you’re stuck either hand-sealing each one (a nightmare) or modifying the can rim yourself (which adds cost per unit).
Let’s get real about real-world use cases, because that’s what matters. Last quarter, we worked with a local pet treat brand that was switching from metal tins to plastic cans to cut shipping costs—metal is way heavier, so they were spending 30% more on freight. They tried their old metal sealer, got a 60% failure rate (cans leaking on store shelves) and came to us. We modified their existing sealer with adjustable heat, plastic-specific rollers, and a groove-cutting roller for the can rims. Now their failure rate is under 1%—and they saved $12k a year on shipping. That’s the kind of win that makes the work worth it.
Wait, but is there any plastic can that a metal sealer can seal? I’ve seen this happen with very small, rigid plastic bottles (like 2 oz travel size) that have a metal lid. If the plastic is super thick and the rim matches a metal can’s rim size, you might get a decent seal, but it’s not reliable. I’d never recommend it for a product that needs to stay fresh—so if you’re using plastic cans for commercial use, don’t cut corners with an old metal machine.
Another myth we hear: “Plastic cans are cheaper to seal than metal.” Not always. The sealer modifications or custom plastic rims can add 5 to 10 cents per can, which is more than sealing a metal can for large batches. But the trade-off is usually worth it for brands chasing sustainability or portability—plastic cans are lighter, so they’re better for e-commerce, and some customers prefer them because they don’t rust. We help brands crunch those numbers all the time, so it’s not a one-size-fits-all.
What about future stuff? A lot of new plastic cans are made from plant-based materials, right? Those are even trickier, because they melt at lower temperatures and stretch more. We’re testing sealers with ultrasonic welding now—no heat, just high-frequency vibrations that bond the plastic lid and can rim together. That works for plant-based plastics, and it’s faster than heat sealing, which is great for high-volume production. We just installed one for a cereal brand that’s using 100% compostable plastic cans, and they’re sealing 1,200 cans an hour without any leaks. Cool stuff, and it’s proof that sealing plastic cans isn’t just possible—it’s evolving.
Wait, let’s address the “but I have a few cans to seal, do I need a machine?” No, wait—if you’re a home baker sealing a few cookie tins (plastic, not metal), a manual tabletop sealer works. But if you’re a small brand doing 100+ cans a week, you need something that’s calibrated for plastic. A lot of people waste money on cheap machines because they don’t ask the right questions: “Is this sealer compatible with plastic can rims and lids?” “Can it adjust for heat if I need a foil seal?” “What’s the failure rate when using plastic?” Those are the questions you should ask a supplier, not just “can it seal plastic cans?”
Now, let’s talk about what we, as a can sealing machine supplier, can offer. We don’t sell one-size-fits-all machines. We have three tiers: tabletop for small batches, floor-standing for medium production, and custom modified sealers for specific plastic can designs. We also test every customer’s can and lid for free before they buy a machine—we run 500 seals, check for leaks, test tamper-evidence, and tell them exactly what they need, no upselling if we think an off-the-shelf metal sealer works (which is rare, but it happens).
But here’s the big takeaway you don’t see on most packaging blogs: Sealing plastic cans isn’t about whether the machine can do it—it’s about whether the machine is set up for plastic’s unique properties. Metal is rigid, plastic is flexible—so your sealer needs to account for that. Skip the generic machines, do your homework on rim thickness and lid type, and test before you invest.
If you’re reading this and you’re sitting on a shelf of leaking plastic cans, or you’re a brand looking to switch from metal to plastic, let’s chat. We don’t just sell machines—we fix sealing problems. We’ll send you a test kit, let you try a modified sealer, and help you tweak your setup so you get consistent, leak-proof seals. Don’t waste more money on machines that don’t get plastic.
Robotic Palletizer References
- Packaging Digest. (2022). Rigid plastic containers: evolving for food and beverage applications.
- Journal of Food Protection. (2021). Seal integrity of plastic packaging containers: mechanical vs. heat-assisted sealing methods.
- Sustainable Packaging Coalition. (2023). Material trade-offs in metal vs. plastic food packaging.
- Industrial Packaging Technology. (2022). Calibration best practices for multi-material can sealing equipment.
Shandong Filling Auto Automation Equipment Co., Ltd.
Shandong Filling Auto Automation Equipment Co., Ltd. is one of the most professional can sealing machine manufacturers and suppliers in China, featured by quality products and competitive price. Please rest assured to buy high-grade can sealing machine for sale here from our factory. Also, customized service is available.
Address: Rongsheng Plaza，Licheng District, Jinan City, Shandong Province, China
E-mail: Info@fillingauto.com
WebSite: https://www.fillingauto.com/
