External Abrasion resistance

Published On:Jan 17,2018

EXTERNAL ABRASION RESISTANCE External Abrasion resistance is the property of the rope which gives it the the ability to resist damage from abrasion due to rubbing on exterior surfaces is an important property. It depends upon:-

• The fibre material
• Wet or dry conditions
• Finish on the fibre
• The rope construction
• Nature of the abrasive surface
• Tension in the rope
• Pressure on the abrasive surface
• Speed of sliding over the surface

There is no standard for quantifying the abrasion resistance. Some generalisations can provide guidance:-

• Polyester especially if treated with a good marine finish resists abrasion well.
• Nylon is good or dry, poor wet, unless treated with a marine finish which provides improvement.
• Aramid is a good performer, wet or dry, but lubricants and marine finishes give better performance.
• HMPE is very abrasion and cut resistant but due to low melting point it can give poor performance if the combination of pressure and speed creates heat.
• Polypropylene is fair to good depending on type and filament size.low melting point is a disadvantage. Blends with polyester perform much better.
• LCP has a very good abrasion resistance.
• Manila is fair but degrades with age.
• Surface yarns and strands should approximately align with the axis of the rope.

  FRICTION The coefficient of friction between ropes and other surfaces is an important consideration in many applications. Frictional heat can cause fibres with low melting points to melt which can lubricate the friction surface reduce the coefficient to near zero and create a dangerous situation. Friction is also essential to make a splice work. Friction coefficients are variable difficulty to quantify and are usually stated as a range the variable are:-

1. fibre material
2. surface material
3. surface conditions
4. finish on the rope fibre
5. pressure against a surface
6. wet or dry-friction coefficient usually increases if the rope is wet.
7. static or dynamic.