Ropes and cables shall be scrapped or stopped from use under the following conditions: ropes and cables are obviously scorched or melted; The linear distance is equal to the length of the rope, and the volume of the surface rope yarn or rope strand is reduced by 10%; The burst and leakage of rope and cable is in the extreme temperature environment beyond the range; UV exposure degradation, rope yarn surface into pieces; The rope appears in the severely damaged hot melting, hardening and flattening area; The number of rope yarns affected by melting or fusion exceeds 20%.
Precautions for the use of rope and cable: before each use, the rope and cable shall be carefully checked for the insertion eye of the mark label, and whether the rope body has cut, broken strand, broken wire, kink and other damaged parts. If there are no abnormalities and defects, it can be used normally; When unfolding the rope, the rope shall be released from the rope end in the circle, and the rope shall be released counterclockwise.
Ropes and cables are mainly used in ship equipment, fishing, port loading and unloading, power construction, oil exploration, national defense and military industry, sporting goods and other fields. Its structure is divided into three strand, eight strand and twelve strand ropes and cables. The products are widely used and have the characteristics of high strength, low elongation, wear resistance, softness and smoothness, convenient operation and so on.
If the rope is unfolded counterclockwise, a rope kink will occur. If there is a kink, put the rope back into the loop, turn the loop, and then pull the rope from the center. A better way is to unfold the rope on a turntable, and then pull the rope from the outer rope end. If people stand under the excessively tensioned rope, it will be dangerous. Once the rope is out of control, it will produce huge tension rebound, which is likely to cause casualties. If the rope is unfolded from the rope shaft, the rope shaft itself shall rotate freely. This can be easily achieved by using a pipe to pass through the center of the rope shaft, but it is prohibited to lay the rope shaft vertically to unfold the rope; If the rope is unfolded from the pulley device, the ratio of the diameter D of the pulley to the diameter D of the rope should exceed 5, but for some high-performance fiber ropes, the ratio can reach 20.
For the rope, it is recommended that the diameter of the pulley groove is 10% - 15% larger than the rope diameter. If the arc of the rope in contact with the pulley groove is 150 degrees, the rope can achieve a good stress state, and the height of the pulley flange should be at least 1.5 times the rope diameter to prevent the marine rope from running out of the pulley. In addition, the pulley shall be inspected frequently and the bearing shall be maintained regularly to ensure smooth rotation of the pulley.
