Certain criteria can change the properties of the material of the lifting straps:
- Substances: Among other things, acids and alkalis can clog the respective material, jeopardising or even preventing reliable use.
- Temperature: The wearing properties of lifting straps can change due to extreme cold and heat.
- Sharp-edged goods and objects: When used to secure cargo in transporters, lifting straps can lie on or constantly graze sharp-edged objects. This poses a risk of the material tearing.
- Wrapping: The material is also influenced by the way in which the goods to be transported are attached or wrapped. If the lifting straps do not lie directly and straight during lifting, the load capacity may be reduced.
Manufacturers must therefore take into account possible temperature fluctuations and sharp-edged objects during development and design, as well as different substances and the type of wrapping. The material used is also called core in the trade and consists of extremely strong multifilament yarn. Polyester (PES) is mostly used for this purpose.
The European standard EN 1492-2 prescribes a special colour coding for lifting straps that indicates the load capacity (with straight tension) of the individual product. This makes it much easier for consumers to choose the right belt.
Round slings that are made of laid fibres and lifting straps that are woven are subject to a prescribed uniform colour code. Products from the same manufacturer with the same colouring therefore have the same load-bearing capacity. For example, round slings and lifting straps with a load capacity of up to 1000 kilograms have the colour violet. Up to a maximum of 5000 kilograms load, the colour code is red, and up to 8000 kilograms it is blue. From 10000 kilograms load capacity round slings and lifting straps are marked in orange. Attention: The load-bearing capacity of the products must never be exceeded in the transporter and in the car within the framework of load safety!
Lifting straps can be attached to hooks of lifting devices after wrapping the object. Another possibility is to attach lifting straps directly to the load by means of a loop. The load-bearing capacity is thus influenced by the type of connection. That is why two straps are often used to secure the cargo in the transporter.
When using lifting straps, users should therefore always follow the manufacturer’s instructions. The respective load-bearing capacity is shown in overviews, depending on the wrapping technique.