How to Use Less Stretch Film for Pallet Unitization

Stretch film, a linear low density polyethylene pallet wrapping material, is the overwhelming choice for unitizing loads for truck and rail shipment. Although a wrapped pallet usually uses one pound of stretch film or less, the weight adds up quickly. U.S. stretch film consumption is in the neighborhood of 1 billion pounds per year.

Shippers can make a big dent in consumption by taking advantage of new film technologies, more efficient equipment, and careful review of their application.

New Films. Since stretch film first became popular in the late 1970's, manufacturers have steadily improved film quality and performance. Today's films stretch more, exert stronger holding force on the load, and have much greater puncture resistance. As a result, shippers can use thinner films and apply less film to their loads without compromising pallet integrity. Unfortunately, in many shipping operations, films are neither tested nor upgraded on a regular basis. A film which was "state of the art" in 2004 may be a mediocre performer by 2008 standards.

Efficient Equipment. Stretch film can be applied to pallets by hand or with a machine. When applied manually, films are typically stretched only 25-40%. However, when applied by a conventional stretch wrap machine employing a rudimentary core braking system, stretch percentages can exceed 100%. To obtain even greater yields, shippers can use machinery with a powered pre-stretching system capable of stretching film as much as 300%. Small volume shippers find it difficult to justify the cost of powered pre-stretch equipment, which runs into the low or mid five-figures. For them a better, less expensive alternative is to retrofit pre-stretch attachments onto existing standard brake machines. For high volume shippers, an ROI of 12 months or less is common when upgrading from conventional to powered pre-stretch equipment.

Review the Application. Because stretch film has the look and feel of kitchen wrap, it is regarded as flimsy. Consequently, shippers tend to use more film that they need to consolidate a load. A typical machine cycle will wrap two or three times at the bottom of the pallet, slowly move up, apply two or three wraps at the top, and slowly move back down to the bottom. By speeding up cycle time and/or eliminating the number of wraps, substantial reductions in film usage can be realized. (As a side benefit, faster, less extensive wrapping increases throughput.)

Take Action. Shippers, regardless of volume, should review film, equipment, and application options annually - at a minimum. An excellent opportunity to survey the market is the heavily attended Pack Expo convention sponsored by the Packaging Machinery Manufacturers Institute (PMMI). Pack Expo rotates between Chicago and Las Vegas and features equipment and film exhibits from all the major players in stretch equipment and film.

Brad Shorr has an extensive background in the packaging industry. He is Director of Marketing for Salazar Packaging, Inc a distribution firm dedicated to helping manufacturers, contract packagers, and distributors find the best sustainable packaging options.  In addition, Brad owns his own sales and marketing consulting firm,  Word Sell, Inc.

Comments

[Victor]

Our company has been manufacturing equipment for packing in the stretch-film. Tell me please, 300% pre-stretching - what a thickness of the film (in microns)? 35, 50, 70?