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Concept
Strapping
Résumé
Strapping, also known as bundling and banding, is the process of applying a strap to an item to combine, stabilize, hold, reinforce, or fasten it. A strap may also be referred to as strapping. Strapping is most commonly used in the packaging industry.
Strap is a flat, flexible material, most commonly made from steel or various types of plastic.
Steel is the oldest and highest tensile strength strapping. It is available in a variety of widths and thicknesses as well as variations in the grade of steel. Steel is used for heavy duty holding where high strength and minimal stretch are desired. Surface finishes for steel strap include: paint, paint and wax, bluing, or zinc and wax. The wax is used to better transmit the tension around the bundle and for use with certain types of tensioners. Common applications include steel coils, bundles of metal, baling wire, bricks and other pavers, and roll end-binding.
Steel strapping is sold by weight rather than length due to the natural expansion and contraction of steel in the manufacturing process. A 3/4 x .020 steel strapping coil yields approximately 19.6 feet per pound.
Polypropylene strap (oriented or ) is an economical material designed for light to medium duty unitizing, palletizing, and bundling. It is available in various widths, thicknesses, and polymer variations (e.g., copolymers). Most polypropylene is embossed, and some is also printed. This product offers higher elongation at break, but tends to have irrecoverable dead stretch with constant stress. What is not generally known to end users is that polypropylene strapping will lose about 50% of the applied tension within one hour, and that this tension loss is accelerated with increases in ambient temperature. Consequently, although it is suitable for packs due to a degree of stored energy that will take up any relaxation that occurs in the strap, unacceptable strap slackness may occur after time if used on solid product, such as brick or concrete. Furthermore, polypropylene strapping is susceptible to UV degradation and can degrade quickly if left exposed to the elements.
Source officielle
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