Fiber cable in the ship's mooring, rely on, the navigation control and plays an important role, both in the towing operation.
And the intensity of the cable is the most concern of the crew.
Broken cable due to cable strength is not enough, the influence of ship safety accidents have occurred.
To manipulate staff in estimation method of cable breaking strength, but the result is not unified, and the cable flexibility estimates are harder to see.
Cable of the elastic modulus is determined by the cable itself, when buying cable should require manufacturers to provide, the relationship between the tensile stress and elongation curve, we use polyester polypropylene high strength against the cable from the corresponding parameter, to dalian maritime university Liu Qi jiang teacher 'the Marine cable strength calculation' polyester fiber tensile stress and elongation of the relationship between the graph is reference, (
Tensile stress in 8.
846 kg/was, corresponding elongation about 16% phi 120 typhoon cable force: 8.
846×πr2 = 8。
14 * 60 * 60 = 99995 kg material 100 tons (
Elongation is 10% when the pulling force, check figure sigma = 5.
6公斤/ mm2P =σ×F = 5。
3 tons & have spent
Phi is the diameter of the rope elongation 10% after 120: ideal state PI r02 * Lara2 L0 = PI in ra2 = (
×r02 = 602/1。
2 da = 114。
From calculation can be obtained, and according to article 13 level three ship line layout of cable set, should be able to meet the requirements of 13 level typhoon, typhoon cable shall be maintained during orgasm appropriate pre-tightening force and the elongation of the cable orgasm remain around 10% for the good, the cable tension is 63 tons, at this time to do this to prevent before must pay attention to the mooring rope direct measurement, according to the result of the measurement of the cable to determine what the cable with the ships, take what position.
Breaking elongation of the cable is not fixed, under the same rope tension changes, decided to breaking elongation of the cable tension change speed, the faster the speed, the smaller the breaking elongation, when typhoon winds can cause the cable force of rapid change, so the results should be retained some allowance.