Stretch wrap and shrink wrap: they are not the same!
Are you confused about what type of wrap to use for transporting your products? Shrink wrap and stretch wrap are there to help you – but they are not made equal! See why.
Transportation can be a trying experience for your products, whether it involves rail, truck, ship, or air freight. Palletising your goods is a first step, as volume increases stability, but you also have to wrap the pallets to protect them and force them to behave as a single structural unit, in order to withstand the stresses of travel. The two methods of wrapping are shrink wrap and stretch wrap, each with its own strengths and weaknesses, but also with its targets and use cases. Let us show you which is which and what each one is good for.
Stretch wrap is a thin plastic film, made from a specially engineered polymer which allows it to extend in length under tension, sometimes up to 300%, creating a thin but durable constrictive wall around your goods. It comes in rolls of long continuous sheets. However, it is a different property of stretch wrap that sets it aside from other plastic wrapping materials: it is also highly adherent to itself! Therefore, multiple layers will not slide between each other but act as a single, almost solid, thicker film! This property of stretch wrap provides the user with great flexibility in wrapping pallets, allowing them to tailor the wrapping of each pallet to specific needs, applying exactly as much wrapping as is needed. Stretch wrap can be applied manually or using wrapping machines, and it does not require special conditions such as heat or light to work.
Shrink wrap is, again, a thin plastic film – albeit not as thin as stretch wrap – that is used to wrap around your goods. It is also, obviously, a specially engineered polymer, but in this case the goal is to give it one specific property: to reduce uniformly in size when heated. This uniformity is critical in that shrink wrap usually comes rolled up but its basic shape is an extremely long cylinder which can be cut and sealed at one end to create a big hood or bag, which will loosely cover your pallet or goods. With the application of heat – usually from a heat gun – the shrink wrap will reduce in size until it tightly envelops the goods. Shrink wrap is not limited in pallets but can be seen anywhere, from wrapping bottles of water or soft drinks up to enormous items – even a helicopter! However, shrink wrap works as a single thick layer and requires the application of heat to work its magic.
When should I use shrink and when stretch wrap?
Shrink wrap and stretch wrap have different use cases with a small (but significant) intersection. Both can protect products and even pallets, but that is the limit of their common usage. Stretch wrap is cost effective, flexible – both in the literal and figurative sense, has a very low-cost entry point (i.e. hand-wrap), and can secure and protect products for transport. Shrink wrap, on the other hand, will secure small products forming larger structural units for palletising, and also protect them from chafing during transportation or storage. Interestingly, shrink wrap and stretch wrap can be used in parallel! Choose wisely and reap the benefits of each.