Some more properties of the Ropes

Published On:Jan 19,2018

Some more properties of the Ropes
Nylon ropes can be ‘shrunk’ by processing the rope through steam. The swelling of the fiber expands the diameter, shortens the rope & increases the extensibility.  The steam process makes the rope very firm & resistant to further ‘shrinkage’. As a property, this is preferred by some users. Polyester fiber can be shrunk by heating. At the higher end of working loads, it will give a rope more elongation on the first few cycles but this soon disappears due to the shrink effect being permanently removed. In the Double braid, a core made of heat-treated polyester will permanently elongate as the rope is loaded to high tension, thus transferring more load to the cover, a modest increase in break strength can be attained compared with producing the entire rope out of the untreated fiber. This shrink effect may also have the application where higher extensibility is required for one-time use.
The ability to be spliced with relative ease can be an important property of any rope. For many applications, the capability to form an eye in the end of the rope as a termination is essential. To be truly spliceable, the procedure should be standardized for the general purpose uses and carried out with a modest amount of training, skills & tools. Some used ropes, although spliceable when new, cannot be spliced after considerable use or shrinkage, or the splices, if made, can be very weak. Nylon braids that have shrunk fall into this category. Almost any rope can be spliced, but specialist skills and tedious procedures are often required. Unless tested, efficiency and reliability may be questionable.
Knot Retention
Knot retention can be an important property for certain applications. Tree service operators, rescue crews, mountain climbers & homeowners trying to secure a ladder use knots. No one wants them to slip. Some ropes hold better than others. Below, are some comments on ropes types:
  • Manilla fiber ropes are “excellent”
  • Eight strands plaited ropes that are tightly twisted & plaited are “good”
  • Polypropylene staple ropes are “good”
  • Nylon three-strand & braids are “poor”
  • Polyester continuous filament braids are “fair”
  • Polyester with staple(fuzz) on the surface is “good”
  • Polypropylene monofilament three stand & braids are “poor”

Three strands laid ropes may be produced in hard, medium or soft lay. Tightly twisted strands and short lay length will produce a hard rope which is very firm, not very flexible and more snag resistant than the other versions. The soft lay rope is stronger and floppy. Medium lay is most common. Plaited ropes are sometimes specified with a hardness req