Preserving the freshness of canned food products is one of the most important things that packagers should take into account. Though there are other preservation methods like drying, salting, and canning, vacuum sealing is still the best option for most types of food. Different preservation methods offer different advantages depending on the food you want to preserve.
Vacuum can sealing machines are among the most widely used can seamers in the packaging industry to give food products their maximum shelf lives. But, do you know how they work? Keep reading to know more!
Vacuum sealing is a process of sealing a container through a vacuum chamber. Vacuum sealing machines remove the air from the containers before sealing them to keep the product fresh for long-term storage. The machine creates a vacuum inside the cans to prevent any compound from entering the containers to avoid food spoilage.
Types of Vacuum Sealing Machines
Vacuum sealing machines come in different models designed for home use and commercial applications. The major difference between these types is the absence/presence of a vacuum chamber unit. Some have built-in vacuum chambers and others don’t.
Chambered Vacuum Sealing Machines
Vacuum sealers with chamber units use vacuum pumps which are more powerful compared to the vacuum channels used by non-chambered vacuum sealers. In these machines, the entire container is placed inside the sealer.
When the chamber closes, the sealer sucks out all of the air inside it. Once all air has evacuated the container, the sealer seals the container tightly. Chambered vacuum sealers are ideal for sealing liquid like beer, powder, and solid products. Most vacuum can sealers are chambered.
Non-Chambered Vacuum Sealing Machines
Vacuum sealing machines for pouches or bags are usually non-chambered. Only the pouch’s edge is processed by the sealer while the rest of its body remains outside. This is why they are also called external vacuum sealing machines.
While chambered vacuum sealers use vacuum pumps, non-chambered ones use vacuum channels used to suck the air inside of the pouches. This makes non-chambered vacuum sealers not ideal for sealing liquids because some of the liquid might get sucked by the machine.
#1 Seaming Head
While the vacuum sealer is sealing the can, the seaming head holds the lid and serves as support from the pressure exerted by the seaming rollers. They have customizable dimensions depending on the diameter of your cans.
#2 Seaming Rollers
The seaming rollers (1st and 2nd operation rolls) connect the can’s lid to its body to create a hermetic seal.
#3 Base Plate
This will spin with the can during the double seaming process. It supports the filled can’s body during the process.
#4 Vacuum Pump
A vacuum pump removes gas molecules inside of the sealed vacuum chamber to create a vacuum.
#5 Vacuum Chamber
This is where the vacuum can sealer performs the can sealing process..
#6 Control Panel
Every sealing machine comes with a control panel where you can set the parameters of the sealing process.
Now, let us proceed with knowing how vacuum can sealers work. Below is a short video you can check out for this:
According to Machine Automation
A vacuum sealer can either come in semi-automatic or fully-automatic design. The working principle of both is similar but there are some differences in how they are operated.
Automatic Vacuum Sealing Machines
Below is how automatic vacuum can sealers work:
Semi-Automatic Manual Vacuum Sealing Machines
Semi-automatic vacuum can sealers work the same way as automatic ones. The only difference is that the semi-automatic vacuum can sealers will need more help from the operator in the sealing process.
The operator needs to manually place each filled container into the machine and start the sealing process using a finger or footswitch. Once the current container is sealed, the operator will repeat the whole process for all remaining containers.
The Double Seaming Process
Once the vacuum sealer has removed all of the air inside the containers, the double seaming process follows.
1. Compression Stage
The machine compresses the can’s body towards the seaming head holding the lid.
2. First Roller Operation
The first seaming roller comes in and interlocks the can body’s flange with the lid’s curl to create a loose seam.
3. Second Roller Operation
Now that you know how vacuum sealing machines work, you might also want to build your own can sealing machine. Learning the fundamentals of packaging is always a good start if you want to enter the industry. This will ensure that whatever problem arises in your production line, you will be able to easily determine where the source of the problem is. We hope that you have learned a lot from this short guide. Or contact Levapack to customize your vacuum can packing line.