INVEST STRAP manufactures high-strength smooth- and corrugated-surface PET straps for automatic and manual packaging.
In recent years, the PET strap has become a popular packaging material, forcing its predecessor, the steel strap, out of the market. Easy and convenient to use, it is by far less costly.
Primarily, PET straps are an alternative to steel straps. In this regard, it is reasonable to compare steel and PET straps by the most important properties for customers.
Strength is one of the crucial properties of packaging straps. Strength of soft steel straps, 12-20 in width, comes to 180-420 kg; semi-cold-worked steel straps have strength of 270-720 kg; cold-worked steel straps are 420-980-kg strong. To compare, polyester straps 12-19-mm wide can ensure strength of 350-950 kg. As you can see, polyester straps are almost equal in strength to cold-worked steel straps; but there is one point to consider.
In cargo strapping, not only strength is critical but also specific elastic elongation, i.e. ability of a strap to extend when the load is applied and get back into the initial state once the load is released. The optimal value of specific elastic elongation for packaging straps is 6-12%, depending on the cargo. Specific elastic elongation of polyester straps amounts to 8-12%.
Russian steel straps offered for strapping are not designed for packaging in most cases. Soft and semi-cold-worked steel straps demonstrate not elastic but plastic elongation: once the dynamic load (shaking and bumping in transit) is applied, they extend and loosen on the pallet.
Cold-worked steel straps have zero specific elastic elongation. Under a high shock impact, a zero-specific-elastic-elongation strap just tears, while even a less strong PET strap will elastically extend, buffer the impact, and return into the initial state.
This explains why when packaging the same cargos with PET and steel straps, polyester straps can be less strong. Besides, elastic elongation helps save 5-10% of the prime cost, which may result in large amounts for large volumes of strapping.
The colors of polyester straps are also worth noting. Production of colored—in most cases green—PET straps was earlier established in Europe, and that color was associated with popular European lines, e.g. Green Line, Blue Line, that campaigned for environmental friendliness and esthetics.
Currently, the green dye for PET straps contains more components aggressive to the environment than the black dye that is based on highly dispersed carbon black. In view of this, green PET straps cannot be considered environment-friendly; moreover, the green dye used in the 2-3 times higher volume than black.
INVENT STRAP LLC manufactures straps of four types:
Black polyester straps ensure higher environment friendliness and strength than straps of other colors. Also, from the psychological point of view, black PET straps inspire more confidence and elicit associations with strong steel straps that were used in all kinds of packaging.
A polyester strap is characterized by high strength and plasticity and low density. Thanks to high freezing resistance, such straps can withstand low temperatures down to -45ºC; therefore, it can be used for packaging any types of products in winter, even in northern regions. As for heat resistance, PET straps can endure temperatures of up to +90ºC.
Polyester strapping can be a perfect option in fields where delicate and reliable product fixation and fastening are required to ensure integrity in transit and storage: especially in metallurgy, petrochemical, and machine engineering industries.
More benefits of polyester straps:
cost efficiency (considering higher dynamic load immunity of PET straps, it is more economically reasonable to use them than steel straps);
weather impact resistance (polyester never rusts and never leaves rust stains on the cargo);
polyester straps do not damage the cargo surface, so in most cases using corner protectors is not necessary;
easy to transport and store (PET straps are 7 times lighter than steel; no sharp edges—no accidental cuts);
extending and deforming, it can return into the initial state, securing the maximum tension).