PVC Yellow Strap
PVC Yellow Strap 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 PVC Yellow Strap. PVC Yellow Strap is used for heavy-duty holding where high strength and minimal stretch are desired. Surface finishes with PVC Yellow 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 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.
Polypropylene strap (oriented or tensilized) 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, some of which is also printed. This product offers higher elongation at break but tends to have an 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 suitable for packs with 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 product that is ‘Solid’ such as bricks or concrete. Further, more polypropylene strapping is susceptible to UV degradation and can quickly degrade if left outside exposed to the elements. The sensible choice of color will retard the process, such as specifying black strap. Similarly, a UV inhibitor can be specified.
Polypropylene strapping may be printed either during production and pre-embossing for the highest quality and precision, or post-production over the embossing for a reduced quality. Both offer security and marketing advantages to the strapped product.