When to Shrink - irregularly shaped loads and conditions requiring extended outside storage or waterproofing generally require shrink wrapping. Loads such as an engine block, bulk parts, furniture and tools/equipment require a solid lock to the pallet. There is no question but that shrink wrap is well suited for these types of applications. Machinery, large equipment, boats and aircraft that are shipped via flat-bed transport or overseas requiring waterproofing or outside storage for extended periods of time are best covered with shrink wrapping. Shrink wrap films are available in bags, sheeting and tubing with printing, colors and additives optional. Two popular additives are UVI (Ultraviolet inhibitor) to prevent sun degradation and VCI (volatile corrosion inhibitor) to stop rust from occurring.

When to Stretch - a wide variety of loads can be unitized with stretch wrapping - bags, boxes, bottles, cans, pails, drums, order picked loads, metal extrusions, roll goods, sheeted products, produce and appliances are typical examples. Generally speaking, because of the difference in energy costs, many shippers are evaluating stretch wrapping first then going to shrink wrapping if the application requires.

When to Strap - Strapping is the oldest method of load stabilization and is still used by many shippers. It may be applied either manually (with or without tools) or automatically by conveyorized equipment. Depending on the properties you need, steel and several types of plastic (nylon, polypropylene, and polyester) are the materials of choice in strapping.

Of all shipping materials, steel provides the highest tensile strength and breaking strength and has the least tension decay, with almost no elongation. For these reasons it is highly suited to rigid, heavy loads where high strength is needed and there is little settling or shrinking of the load.

Strapping as a unitizing method is used to secure bundles of piping, lumber, bales, panels and trusses. It is ideal for long, uniform A type loads. Other applications include the strapping of crates, equipment and large machinery.

Polyester is the strongest of the plastics, with the highest retained tension capability. As such, it is frequently used on heavy rigid loads where high retention of strap tension is required. It competes well against standard gauges of steel strapping.