How to calculate the required load capacity of a rope?

Rope strength is always stated in daN units and is one of the basic characteristics when buying a rope. It is the force in N (Newtons) that is applied when the rope breaks. An approximate conversion to kg can be determined -> daN (1 kg = 0.981 daN).

It is necessary to distinguish between the maximum rope strength and its working load limit. The working load limit is the maximum load on the rope that must not be exceeded and depends on the specified safety factor.

For safety reasons, when using a rope for lifting objects, we must consider a safety factor that determines the rope’s working load limit.

For example: a rope with a minimum strength of 500 kg, used for lifting a load and with a safety factor of 5:1, has a working load limit of 100 kg.

At the same time, it is necessary to consider how the rope will be used. Knots reduce rope strength by up to 50%; for steel wire ropes, up to 90%; splices by about 10%; and also the effects of weather conditions, UV radiation, chemicals, or abrasion of the rope itself.