Multipack formats and their main engineering questions| Bundle route | Main selection questions | Finished-pack evidence |
|---|
| Tray-supported bundle | Tray rigidity, wall height, product overhang, sharp corners, base clearance and whether the tray distorts under tunnel heat. | Tray remains square, film draws consistently and the base can transfer without snagging. |
| Pad-supported bundle | Pad stiffness, moisture resistance, product retention before shrink and the position of exposed edges. | Pad does not curl or move, and the cooled sleeve holds the group through lifting and accumulation. |
| Trayless bottles or cans | Container stability, base geometry, surface friction, row control, label scuffing and side support during transfer. | Rows remain aligned and the film provides the agreed carrying integrity without damaging individual containers. |
| Grouped cartons or cases | Corner strength, print rub, closure security, bundle mass, film overlap and the downstream handling method. | Cartons remain undistorted and the group survives the specified conveyor and manual or pallet handling. |
Inspect the pack after cooling and representative handling
A hot bundle can look acceptable at the tunnel exit but fail when it meets a guide, transfers across a gap or is lifted. Approval should therefore include the intended discharge route, cooling time, accumulation pressure and at least one handling check that represents production. For a heavier group, assess whether the tray or pad carries the load or whether the film is being asked to provide more support than intended.
Film evaluation should include seal continuity, corner thinning, holes, loose lower film and movement of the product within the sleeve. Tunnel settings should be judged with normal line loading and spacing, because long gaps and continuous flow can produce different heat balances.
Keep adjacent packaging intents on the correct specialist route
This site owns grouped-product sleeve wrapping. For a suitable individual product that needs full film enclosure, use the L-sealing machinery route. For a closed corrugated case that needs top-and-bottom tape rather than shrink film, use the specialist case taping machinery route.
