Strapping can be divided into 6 types:
- Extruded Polypropylene (PP)
- Extruded Polyester (PET)
- Glued Polyester (Hotmelt)
- Co-extruded Polyester (Composite)
- Woven Polyester
- Woven Polypropylene
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Strapping is primarily intended for the safe transportation of often expensive loads. In spite of this there are hardly any regulations with which strapping must comply.
Because of this a decision is often made on the basis of the lowest price.
The wrong strapping is also regularly selected for the wrong application.
Often this results in damage or unsafe situations.
Use for trains and trucking in the USA should, however, comply with the American Standard for Testing Methods (ASTM 3950 D - series).
An application for approval should be made for each type of strapping in combination with a buckle.
A number of manufacturers of strapping in the USA/Canada have acquired their required approvals with Veltkamp buckles.
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Tensile strength
| The quality of strapping lies in, among other things, its tensile strenght. In order to score as high as possible, the system tensile strength without buckle is often assumed. |
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For a proper, safe picture, however, the lineair tensile strength with buckle and with pretension must be assumed.
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Pre-tension
Is the strength to which is tightened using a
tensioner. This varies from about 5kg for the 9 mm
strapping to 25kg for the 50mm strapping.
Important to know
The system strength of strapping with buckle
under pre-tension is 30-50% of the linear
tensile strength without buckle.
This is because the disortion of the strapping
is greatest in the buckle.
The strapping therefore fails first.
If use is made of a strap fastener or a frame
with pre-tension then the system strength
is 20-35% of the linear tensile strength
without a fastener.
This is because the disortion of and damage
to the strapping is greater in a strap fastener
or frame.
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