Technical notes
ROTATIONAL PROPERTIES
Rotation-resistant ropes are ropes that are designed such that they create a reduced torque and a reduced rotation under load. In general, they are composed of a construction of at least two strand layers that are helically stranded around a core. The outer strand layers in this construction are stranded opposite to the strand layer below.
ROTATION-RESISTANT A
The rotational property is less than or equal to 1 rotation/1,000 d, when a load corresponding to 20% of the minimum breaking force is lifted; a swivel may be used.
ROTATION-RESISTANT B
The rotational property is greater than 1 rotation but less than 4 rotations/1,000 d, when a load corresponding to 20% of the minimum breaking force is lifted; a swivel may be used in accordance with the recommendations of the rope manufacturer and/or with the approval of a competent person.
NOT ROTATION-RESISTANT
The rotational property is greater than 4 rotations/1,000 d under a load corresponding to 20% of the minimum breaking force; a swivel should not be used.
1 rotation = 360°
d = rope diameter
Fmin = minimum breaking force of the rope