ELONGATION AND PRE-STRETCHING
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The Tensile Strength depends on the:
- amount of yarns
- quality of the yarns
- and the density of the yarns
Polyester - PET
- stronger than normal PP
- yarns are cheaper
- gets stiff, especially at low temperatures
- almost no elongation, no sufficient stretch capacity, less shockproof
Pre-Stretched
Polypropylene - PP
- stronger than PET
- yarns are more expensive
- pursue soft and flexible nevertheless the temperature
- comfortable to use
- very high shock absorption
- most suitable for cargo securing
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Pre-Stretching Influence
To reduce the disadvantage high elongation manufacturers pre-stretch the strapping during the production process.
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Therefore the already woven PP undergone a special heat-setting treatment and pre-stretching in order to minimise the elongation of the fibre and the woven structure to the optimum value.
Under normal circumstances is the working load the same.
However, under heavy duty circumstances and a variable load (shock absorption) the Pre-Stretched PP performs better.
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