The essential aim of the Shrink wrapping process of heat shrink machine is to place shrink film around the product prior to shrinking. There are two principle forms of wrapping:

i)Sleeve wrapping –Shrink wrapping bottles ,boxes etc by ready sleeve

ii)Overwrapping – Shrink Wrapping the bottles, boxes etc totally wrapping and shrinking

Sleeve wrapping- Sleeve Shrink Wrapping  - best suited for secondary and tertiary packaging. The process is easily automated, uses low cost material and has low labour input. Sleeve wrapping is readily applied to regular shaped products that need to be collated into larger, easier to handle packs for palletising, warehousing or distribution.

Sleeve wrapping is performed using two rolls of flat sheet shrink film. The ends of the sheets are heat sealed together forming a vertical curtain. Product is pushed through the film curtain to a position behind the Welding bar.

The welding bar descends in front of the pack, completing the sleeve of film, parting the sleeve from the rest of the film and reforming the film curtain for the next pack.

The sleeved pack then passes to the shrink tunnel where film shrinking takes place.
The resultant pack will is Not totally enclosed. Each end of the pack has an opening due to the original wrap being only a sleeve.

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