Why the shrink tunnel matters
A sleeve sealer can only produce a finished pack if the shrink tunnel has enough chamber length, aperture, airflow and heat control for the product and film. Poor tunnel matching can lead to loose film, distorted packs, excessive heat exposure or inconsistent presentation.
Bottles, cans, trays and cartons behave differently in the tunnel. The pack weight, open sides, film thickness and desired finish all influence the tunnel recommendation.
Tunnel sizing questions
The first sizing question is the finished pack width and height. The tunnel aperture must allow safe clearance without excess wasted heat. The second question is dwell time, which depends on belt speed, chamber length and the time the film needs to shrink correctly.
Airflow is also important. PE shrink film and heavier transit packs often need a tunnel that can deliver consistent heat around the pack, not just a high temperature setting.
Matching the tunnel to the sealer
The tunnel should be considered at the same time as the sleeve sealer. Infeed height, conveyor transfer, pack spacing and discharge handling all need to work as one packaging route.
If you already have a sealer but need a better tunnel, provide the current machine details, pack sizes and photographs of the shrink result so Lancing can advise what may be causing the issue.
Quote route and specification checklist
| Tunnel factor | Specification impact |
|---|---|
| Aperture size | Must clear the product and film without excessive wasted heat. |
| Chamber length | Affects dwell time and real output. |
| Airflow | Controls consistency of shrink finish. |
| Belt speed | Balances output against film shrink time. |