Kernmantle rope

From Wikipedia, the free encyclopedia

Parachute cord is a type of lightweight nylon kernmantle rope. The kern of this particular example is made up of seven two-ply yarns, the mantle is braided from 32 strands.

Kernmantle rope is rope constructed with its interior core (the kern) protected with a woven exterior sheath (mantle) that is designed to optimize strength, durability, and flexibility.

[edit] Use as climbing rope

The nylon ropes that were used in yachts for hauling were tested and found useful in climbing and caving, and are now the modern standard. Although there are occasional innovations, the type of rope used today is similar in construction, strength, and durability across manufacturers. There are several major manufacturers, including Pigeon Mountain Industries or PMI, Mammut, Edelweiss, Blue Water, Roca, and Maxim. Kernmantle ropes are still used in sailing and other sports, however the technical requirements are usually not as rigorous as in climbing since the applications are not as safety critical. Smaller kernmantle ropes are commonly called cordalette or accessory cord. They are often used to make prusik knots and loops or attaching accessories such as chalk bags.

One or more of the rope characteristics (strength, durability flexibility) are often altered somewhat, depending upon the ultimate use of the rope, at the expense of the other properties. For example, rope used in caving is generally exposed to more abrasion than other forms of recreation, so the mantle is woven more tightly than rope used in climbing or rappelling. However, the resulting rope is cumbersome and difficult to tie knots in.

Kernmantle construction may be used with both static and dynamic ropes. Static ropes are designed to allow relatively little stretch, which is most useful for hauling, rappelling, and other applications. Dynamic rope is used to belay climbers, and is designed to stretch under heavy load to absorb the shock of a fallen climber. Dynamic ropes are usually rated for a given number of falls, meaning the rope is to be retired after it has accumulated a certain amount of damage. The shock loading of a rope from a fall should be taken in context, so that a rope that has been used longer and harder should be retired sooner than the manufacturer suggests, based on the number of falls alone.

[edit] Rope care

Kernmantle rope should be inspected after every use for any form of damage. "Boogers," which indicate internal damage to the kern, will appear as tufts of white threads poking out from the mantle. Ropes that have been severely stressed will have tapered sections to the rope, where it is visibly or palpably thinner. Rope that has been abraded or cut on sharp edges should be examined closely by an experienced user who may choose to cut the rope at that point, rather than risk it parting at that area.

Rope may be cleaned by chaining it, and washing it in a front-loading clothes washing machine with soap flakes. Strong cleansers, including bleach and detergent should not be used with life-critical Nylon components. Commercial rope cleaning devices are available from the climbing and rescue companies CMI and PMI. Directions for making a similar device can be found here.

[edit] Typical specifications

^*Dynamic ropes are rated for a certain number of falls (usually 5-10) at a given impact force.

[edit] References

Mammut Static Rope specifications

[edit] See also

• Dynamic rope
• Static rope
• Climbing equipment
• Sailing