How to buy the best shrink-wrapper
Three tips for buying the best wrapper for the application.
Shrink-wrapped products in trays, on pads, or simply bundled in polyethylene film are a cost effective and sustainable way to transport palletized consumer products through the distribution network. Shrink wrapping offers significantly lower material costs by reducing or eliminating the need for higher priced corrugated board. Film in this application is a more sustainable choice than corrugated because less material is sourced. Rolls of film take up a smaller amount of room in over-the-road trailers, offering savings on transportation, and film rolls conserve warehouse space compared to corrugated shipping cases. Retailers appreciate the easier handling of films. And, polyethylene film is every bit as recyclable as corrugated, another plus in terms of sustainability. In an era demanding economical packaging that uses less material and is recyclable, packaging utilizing polyethylene shrink film for multipacks makes sense.
Buying tip one: Partner with a shrink wrap original equipment manufacturer (OEM) to test pallet loads of multipacks in the distribution network.
The high-stacking strength and stability of many primary or secondary packaging makes those packages ideal for film-only shrink bundles when palletized. Some packaging may need the support of trays or corrugated pads on a pallet. There are, however, fragile products or less strong primary and secondary packaging not suitable for shrink-wrapped distribution. The problem is how to determine whether the product and packaging in question are candidates for shrink-wrapped multipacks.
The first tip to purchasing a shrink wrapper is to partner with a supplier that is set up to, and encourages, test runs of shrink wrapping and palletizing multipacks. A first tier OEM will evaluate trays, pads, and unsupported bundles in various pack patterns. The OEM will palletize the multipacks and prepare them for transport through the distribution network. For the utmost in ascertaining the feasibility of shrink wrapping, the OEM will make pallet loads available to testing labs. Upfront testing of products new to shrink wrapping is an excellent strategy for not only determining feasibility and projected savings, but also to determine optimum pack patterns and whether trays or pads are required.
Buying tip two: Match the application to one of the three general types of shrink wrappers.
Basic shrink wrappers run in semi-automatic mode at 5 to 10 multipacks per minute. An operator packs a tray, or forms a desired pattern on a pad or for an unsupported bundle, pushes the multipack through the polyethylene film, and then presses an activation button. The machine wraps the multipack and conveys it through the heat tunnel for shrinking.
Intermittent wrappers offer production speeds of up to 25 units per minute. Intermittent machines have an automated collation system for various pack patterns. Packages come in, are collated automatically, and then are mechanically pushed through the film. These machines, depending on how they are specified, can shrink wrap packages already packed in trays or can form a tray around the packages. Pads can be inserted for extra support for non-tray pack patterns, or unsupported packages can be collated and automatically pushed through the film. Changeover between pack patterns can be made manually or automatically based on the type of machine specified, with recipe controlled changeover ideal for lines running a number of different pack patterns. Visualize future requirements and plan ahead to ensure the machine specified will be able to accommodate emerging packaging requirements on the line in question in terms of number of changeovers, pack patterns, and variety of package.
Continuous motion multi-lane machines can wrap in excess of 100 units per minute for unsupported bundles. Continuous motion wrappers collate flights of packages coming in so that there is an uninterrupted flow of product through the machine.
Leading suppliers of intermittent and continuous machines have the expertise to develop shrink wrappers with integrated labeling, case packing, robotic palletizing, and stretch wrapping systems. These same suppliers can provide all-in-one machines – trays, pads, and bundles – for those operations that have a wide mix of products.
Buying tip three: Examine a few critical components, systems and support.
All things considered, the most trouble free, long lasting machines will feature robust welded frames. Without this strength, operational vibration will cause parts to wear out fast and will tend to throw the machine out of specification. The best suppliers will offer both mild steel with powder-coated welded frames for normal operating environments and stainless steel-welded frames for harsh wash-down environments.
Ascertain whether the supplier will provide the appropriate NEMA rated enclosure for the plant environment. This is particularly important for harsh environments. Make sure the OEM can supply an air conditioned panel for plants that experience hot summer temperatures. Today’s electronics generate considerable heat, which must be dissipated in order to prolong the service life of expensive components. The top OEM will feature robotic cabling, which like robust frames leads to long life with fewer repairs.
There may be a large gap in price between different suppliers for the same class of machine. This usually indicates the lower priced OEM is using components from tier two or three suppliers in order to drive down the price of the machine. Low purchase price does not ensure lowest overall lifecycle cost. Ask about the mean time between failure ratings of important components such as motors and drives. Ascertain the level of local availability of parts. Ask the OEM about its training and tech support infrastructure: Are the trainers PMMI certified? How does the OEM handle third shift and weekend calls? Are remote diagnostics offered?
For the appropriate product and package, it is hard to beat shrink wrapped multipacks. The three purchasing tips summarized below are time tested and should lead to an optimum purchase.
If the packaging hasn’t been shrink wrapped before, it is best to work with a supplier that routinely does test runs.
Look at the suppliers’ line ups of equipment and, in general, give preference to full spectrum suppliers, those with all three classes of machines.
Investigate the key components and systems. The important considerations are robustness, local availability of parts, and commitment to training and support.