13 Questions
What is the main advantage of man-made fibre ropes over natural fibre ropes?
They are more elastic and have greater strength
What is a common characteristic of some synthetic ropes?
They always float in water
What is a disadvantage of synthetic ropes when left immersed in water for a long period of time?
They lose strength
What is Italian Hemp known for?
Having a strength one-fifth greater than top-grade manila
What is another name for Polyamide (PA)?
Nylon
What are the three basic materials used to make ropes?
Natural Fibres, Synthetic Fibres, and Steel Wires
What is the characteristic of Manila rope that makes it suitable for pilot ladders?
It is smooth, glossy, strong, flexible, and has high resistance to sea-water rotting
What is the main source of Sisal fibre?
Aloe leaves
What is the elasticity of Coir rope as a three-stranded rope?
45% of its length
What is the origin of Hemp fibre?
Russia
What is the main consideration for using ropes onboard ships?
Strength and characteristics of the rope
What is the approximate stretch of Manila rope?
25% of its length
Why is Sisal rope not commonly used for Marine work?
Manila rope is available
Study Notes
The Formation of a Rope
- To effectively use and maintain ropes, you need to know what they're made of, how they're constructed, and their characteristics.
- Understanding ropes helps you identify potential damage and take measures to minimize or prevent it.
Types of Ropes
- Ropes are made from three basic materials:
- Natural Fibres
- Synthetic (man-made) Fibres
- Steel Wires
Natural Fibre Ropes
- Examples of natural fibre ropes include:
- Manila
- Sisal
- Hemp
- Coir
Manila Rope
- Made from abaca fibre, which comes from the abaca plant (banana family).
- Characteristics: smooth, glossy, strong, flexible, easy to handle, and resistant to sea-water rotting.
- Mostly used for pilot ladders.
- Stretches about 25% of its length.
Sisal Rope
- Made from aloe leaves (pineapple family).
- Characteristics: white in color, hairy surface, and swells more than Manila when wet.
- Not generally suitable for Marine work where Manila is available.
Coir Rope
- Made from coconut fibre (removed from the shell after soaking).
- As a cable laid rope, coir stretches between 60 and 100%.
- As a three-stranded rope, its elasticity is about 45%.
Hemp Rope
- Originally from Russia, now exported from other countries.
- Italian Hemp is considered the best-quality hemp, with strength one-fifth greater than top-grade Manila.
- Has been replaced by Manila.
Synthetic or Man-made Fiber Ropes
- Examples of synthetic fibre ropes include:
- Polypropylene
- Polyamide (Nylon)
- Polyester (Terylene or Dacron)
- Polyethylene
Characteristics of Synthetic Ropes
- Greater strength allows for smaller ropes to carry heavier loads.
- Greater elasticity (ability to stretch) for shock absorption.
- Some synthetic materials float, while others do not.
- Some synthetic ropes lose strength when left immersed in water for long periods.
Learn about the basics of rope construction, materials, characteristics, and how to prevent damages. Understand the strengths and weaknesses of different rope types based on their fibres.
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