Installation elongation vs. rope elongation

1. Extension of installation:

• Occurs when new ropes are first used.
• Is caused by “running in” of fibers and settlement of strands.
• Perhaps significant (up to 10% for certain ropes).
• Must be taken into account when installing ropes.

2. Elongation in use:

• Occurs under the effect of the load applied to the ropes.
• Is generally lower than the installation elongation (around 1 to 2% for ropes in good condition).
• Must be monitored and compensated if necessary.

Differences:

• Timing: Set-up elongation occurs during first use, while in-use elongation occurs throughout the life of the rope.
• Cause: Elongation in place is caused by “running in” of the fibers, while elongation in use is caused by the applied load.
• Importance: The elongation in place is generally greater than the elongation in use.

Advice :

1 For extension of installation:
o Allow sufficient margin when installing new ropes.
o Take the ropes back to the winch after installation.

• For elongation in use:

o Inspect ropes regularly for signs of wear.
o Replace worn or damaged ropes.
o Monitor the rope tension and adjust it if necessary.

In conclusion, it is important to understand the difference between the elongation when setting up and the elongation in use of ropes.

This will allow you to choose the ropes suited to your needs and use them safely.