Process guide
A direct explanation of film presentation, sealing, controlled heat, cooling and the machinery routes used for individual packs, multipacks and sleeves.
Process explained
A shrink wrapping machine places heat-shrinkable film around a product or group, creates the required seal or overlap, then exposes the film to controlled heat so it contracts. The pack must cool before tight guides, accumulation or compression. The exact sequence differs between L-sealers, sleeve sealers, chamber machines and sleeve-label systems.
Guide a single product or a stable group into the film path at the intended orientation and spacing.
Enclose the pack in centre-folded film, form a sleeve, use a preformed bag or position a label or band.
Seal and cut the film where the selected process requires a closed edge or transverse joint.
Apply controlled heat, then support the pack until the film has reached the accepted handling condition.
| Route | How film is presented | Where heat is applied | Typical decision |
|---|---|---|---|
| L-sealer line | Product enters centre-folded or compatible presentation film and open edges are sealed | Separate conveyor heat tunnel | Individual products requiring a controlled presentation wrap |
| Sleeve-sealer line | Film forms a sleeve around a stable product group | Separate tunnel sized for the bundle and PE-related duty | Multipacks and open-sided transit bundles |
| Chamber machine | Operator places the product in a bag or loose-film envelope | Inside the same chamber after sealing | Compact batch production and mixed low-volume work |
| Sleeve label or band | A preformed sleeve, label or tamper band is positioned on a container | Localised hot-air or other suitable shrink process | Container decoration, capsule or tamper-indicating applications |
Video description: shrink wrapping machinery conveys wrapped products through sealing and heated stages. Use the video to understand flow and guarding context; it is not a substitute for product-specific speed, setting or acceptance evidence.
Common process questions
The answers below separate the film, sealing and heating functions that are often grouped under one machine name.
No. Some chamber machines combine sealing and shrinking, while many production lines use a separate sealer or sleeve wrapper followed by a conveyor heat tunnel. Sleeve-label systems may apply a preformed sleeve and use a separate localised shrink process.
Identify the actual equipment boundary in the quotation so power, controls, guarding, cooling and line responsibility are clear.
The sealing stage joins or closes the film so it can remain around the product while the film contracts. The seal must suit the exact film and pack geometry and must remain intact through the tunnel and later handling.
A weak or contaminated seal cannot normally be repaired by adding tunnel heat; the sealing cause should be corrected first.
Film can remain warm and mechanically unstable when it leaves the heated zone. Cooling allows the pack to settle before close guides, accumulation, labelling, case packing or stacking. Without enough support and cooling, an acceptable tunnel finish can distort downstream.
The acceptance point should therefore be defined at the next real handling operation, not only at the tunnel exit.
Sometimes, but the two duties may need different film paths, seal arrangements, product presentation and tunnel conditions. A machine should not be assumed to cover both merely because the outside dimensions fit.
Test representative single packs and groups, including the smallest and largest formats, then compare the changeover and accepted output for each route.
The film can balloon, delay contact with the product and create loose areas or distorted seals. Air release may come from approved perforation, the seal arrangement or another controlled feature of the film process.
Do not improvise perforation without confirming the packaging and product requirements. Record the approved air-release method with the film specification.
Shrink film contracts around the pack; it is not normally intended to act like an adhesive. Contact pressure, surface friction and the pack shape help the film conform, but the finished result depends on the selected material and process.
Where a product surface, print or coating could mark, rub or transfer, include that risk in the sample trial and acceptance check.
Application review
Send product photographs or video, film information, pack orientation, required output and the adjacent equipment so the correct process route can be assessed.