Heat-method guide
A direct comparison of manual hot-air application and conveyor shrink tunnels for production, development and product trials.
Heat-method comparison
A heat gun applies hot air manually to selected areas, while a shrink tunnel conveys packs through a controlled heated environment. A heat gun may support authorised low-volume or development work where the risk assessment and film process allow it; a tunnel is normally easier to specify for repeatable production loading and integration.
| Factor | Heat gun | Shrink tunnel |
|---|---|---|
| Heat application | Manual, local and dependent on operator movement and distance | Pack follows a controlled conveyor path through circulating heat |
| Repeatability | Depends strongly on the approved manual method and operator consistency | Recipe can control indicated temperature, speed, airflow and loading |
| Production flow | Suited only where manual handling and dwell are practical and safe | Can be integrated with sealers, sleeve applicators and downstream conveyors |
| Evidence required | Method, operator training, product support, ventilation and accepted finish | Film, actual speed, loading, airflow, recovery, cooling and line interfaces |
Buyer questions
Manual and conveyor heat methods should be compared by repeatability, product risk, operator method and accepted output rather than purchase cost alone.
A heat gun may be acceptable for authorised occasional work, development samples or a process specifically designed for manual heat application. The film, product, ventilation, hot-air exposure, operator method and risk assessment must support that use.
It should not be assumed suitable for continuous production or used to bypass the safeguarding and process controls of a purpose-designed machine.
A tunnel can control the pack path, indicated temperature, conveyor speed, airflow and loading within a recorded recipe. This reduces variation caused by the angle, distance and movement of a handheld heat source.
Repeatability still depends on stable film, sealing, product orientation, spacing, recovery and cooling; a tunnel is not self-correcting.
No. A heat-gun sample can show that a film may shrink around a product, but it does not reproduce tunnel airflow, residence time, conveyor contact, thermal loading or cooling. It is not sufficient evidence for sustained tunnel production.
Use the proposed tunnel or a representative equivalent for the acceptance trial.
It may be useful for limited development or local work, but printed sleeves often require controlled shrink direction, placement and distortion around container features. A production method should be proven with the actual print, container, contents and closure.
Where repeatable appearance matters, compare the manual result with a controlled hot-air or other purpose-designed sleeve-shrink process.
Both methods involve heat and require a suitable risk assessment. A heat gun adds sustained manual handling and a movable hot-air source; a tunnel adds conveyors, hot surfaces, guarding, controls and possible line integration. Film and product information may also affect ventilation requirements.
Use the machine instructions and competent site assessment rather than assuming one method is inherently safe for every application.
Consider a tunnel when accepted pack quality, operator workload, sustained output or integration cannot be controlled reliably with the manual method. Repeated variation, product damage or excessive handling are also reasons to review the process.
The change should be based on a representative trial and a complete line review, not only on a target number of packs.
Heat-process review
Send the product, film, accepted finish, batch profile, operator method and required output so Lancing can assess whether a conveyor tunnel is justified.