Elongation Test Total stretch represents the entire length change in a new rope when placed under a given stress (load) and includes the non-recoverable, recoverable overtime and immediately recoverable portions of extension. One of the variables affecting percentages of elongation is intermittent loading vs. sustained loading; plotted graphically, the curves are somewhat different. Two marks are made on Marina Maxi Rope 30 inches apart, then tightly knot up a piece of string or twine made of same material through the strands at these marks. The string measure 34-1/2 inches between knots. When the rope is put under load of 20% of its breaking strength it is elongated less than 15% between the two knots 30" apart when relaxed will now be 34-1/2" apart (30"+0.15x30 = 34-1/2") and the string is taut.
Conclusion If the string would have snapped out then it is to be believed that the rope has been loaded more than the breaking strength as well as if the distance have been more than 34-1/2" then the elongation is more than 15% which is not the case in our sample.
| | | | Properties
- Specific Gravity: 0.99
- Melting Point: 185oC
- Breaking Load Reduction of Wet Rope: 0%
- Bending Ratio: 9:1
- Elongation at Breaking Point: 15%
- Water Absorption: 0%
Distinctive Advantages
- Float On Water
- High Breaking Strength
- High Abrasion Resistence
- High Shock Absorption
- No Loss Of Strength When Wet
- Low Weight-Easy Handling
- Very Low Snap-Back Effect
- Low Elongation
Application
- Mooring Lines For 0.1 Tanker
- Towing Lines
- Anchoring Lines
- SPM Hawsers
- Messenger Lines
- Offshore Applications
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