Mountaineering and climbing require two types of ropes: static rope, and dynamic rope. Most of you can’t differentiate between a static rope and a dynamic rope. Therefore, in this article we are going to tell you everything about static rope and dynamic rope.
What’s the Difference Between Dynamic and Static Ropes?
A dynamic rope is a climbing rope that is primarily used to catch a climber falling or slipping on a wall. Due to their elasticity, such ropes can better absorb the energy generated during a fall.
Ropes that are flexible and stretchy – i.e. dynamic ropes – must comply with EN 892. If they fall, they should be able to cushion the so-called “catch impact.”. They must, however, be capable of absorbing loads so that when they fall, the ropes do not tear.
A (semi-)static climbing rope could suddenly stop a slipped climber, but if the rope lacked elasticity with a lack of elasticity, the consequences would be much more painful.
A static rope is correctly described as a semi-static fixed rope by the maximum permissible elongation of five percent. Static ropes typically have a thickness between nine and thirteen millimeters and ropes that are semi-static can be used for cannoning, for the construction of high rope courses, or as safety ropes for height rescues. In cave exploration, static ropes are also used.
The high impact force of semi-static ropes during climbing tours can lead to serious injuries when there is a fall. In terms of elongation and strength, semi-static ropes are compliant with the EN 1891 standard. They can only reach their maximum thickness and strength. The life of an injured climber or accident victim may depend on them. The use of thinner rope cords when leading the rescue of an injured person violates the most important rules of rope use.
Dynamic or static: the fall factor is relevant
It is determined, among other things, by the fall factor of each rope, whether it is dynamic or static: The fall factor equals the fall length divided by the working rope.
A fall factor of 0 to 2 is standard depending on how the rope is used. It can also produce a higher force on fixed rope courses. There can be a 7 fall factor in this case. As a result, the impact force is very high when unfavorable conditions are present. This can cause the rope to break. Serious injuries are inevitably caused. You will have to carry a special rope set on a fixed rope course that contains a shock absorber.
Other factors that can affect the service life of a climbing rope include:
- Rope usage frequency
- as well as how the rope should be used
- based on its age
- in addition to its noticeable abrasion
- as well as its impregnation
- of mechanical, thermal and chemical loads
- as well as its number of falls caught already
- or the rope’s storage.
Fall factor and impact force
It is important to understand that the impact force is influenced by rope structure, fall factor, and body weight. Climbing fans should also consider how they secured themselves. Naturally, how long climbing ropes have been used and how many falls they have caught also plays a role. The forces acting on a climbing rope during a fall add up. This includes the tensile forces exerted by the fall end and the tensile forces exerted by the securer.
The climbing enthusiast should, therefore, be able to calculate how high the impact could be if he uses intermediate safety devices. As low as possible should be the load on the climbing rope caused by the impact. Preventing a fall is, of course, the most important measure. In the event of slipping, however, you should be optimally secured and have correctly assessed the impact.
Can the impact force be actively reduced?
The first step is to apply the first intermediate backup as soon as possible. The fall factor is already reduced. If climbing a fixed rope route, this should always be kept as low as possible. Intermediate backups should be installed closely. For ice climbing, energy absorbers are mostly used. Shock absorbers are worth using even if safety points are to be used naturally.
By using a loose rope guide at the securing points, the friction can be kept as low as possible. The rope can then become effective throughout its entire length in the event of a fall. Besides dynamic climbing ropes, dynamic fall handling can also be trained. The rope can cushion a fall and lessen its impact.
Ropes that are static cannot accomplish that. They do not absorb the released energy. As a result, static climbing ropes and thick rope cords should never be used on the rock. The rope, securing points or the climber himself can sustain heavy loads after even a short fall into static webbing slings.
Inside a dynamic climbing rope, what does it look like?
However, tensile strength is a relative measure at sharp rock edges and high friction intensities. On sharp-edged rock ridges, material melting and climbing rope cuts sometimes occur under high tensile loads. Various factors can cause this, including improper use, incorrect storage, ropes that have already exceeded their service life, and unfortunate chain of circumstances. Dynamic climbing ropes are designed to prevent a strong impact. Such climbing ropes must also have elasticity in addition to strength. In order to meet both criteria, dynamic climbing ropes must be manufactured.
Interwoven rope strands make up the inner workings of a dynamic climbing rope. They should not be interrupted throughout its length. In addition to a core, the rope is sheathed and has a control thread selected for identification each year.
For dynamic climbing ropes, polyamide fibers have proven to be the best material. Synthetic fibers are exactly what dynamic climbing ropes need in terms of elasticity, stretchability, and strength. Others are proving less suitable for absorption of impact.
Inside a static climbing rope, what does it look like?
(Semi-)static ropes also contain interwoven textile fibers, which are surrounded by a protective covering. Semi-static ropes are constructed similarly to dynamic climbing ropes.
However, in this case, the rope core should not yield under load. Thus, sheathed strands help to ensure that such ropes can bear the weight of a load. The jacket protects the inside from external influences such as heat, and mechanical forces.
Also shown here is a control stripe indicating its properties. In the case of frequent rope damage, this can provide a manufacturer with important information about a specific batch of material or a defined production period.
Are ropes dynamic, semi-static, or static?
An answer to this question can be found by examining the length of elongation in use, i.e. what happens when a rope is pulled. Ropes used for dynamic climbing have a maximum elongation of eight percent. This elongation is achieved during rope manufacturing by manipulating the material.
On the one hand, the twists of the rope core are interlocked and twisted together. Alternatively, they are shrunk in an autoclave by using heat and pressure as well as a certain exposure time. In this way, an expansion reserve is formed.
It is an artificially produced elasticity, but it cannot be attributed to elastic materials.
Ropes that are semi-static or static have a maximum elongation capacity of two to five percent. Different national or EU standards govern how such ropes must be designed.
How do single ropes, half ropes, and twin ropes differ?
Dynamic climbing ropes come in three varieties: single rope, half rope, and twin rope. You can identify these by a mark on the end.
On the left side of the single rope is a round symbol. The top right corner of the half rope also carries a round symbol. Below that, on the twin ropes, is a round symbol.
Ropes with only one strand are preferred for climbing gyms and high ropes courses. This rope’s diameter should not exceed 11 millimeters. It must comply with the requirements of EN 892 in the following ways:
- Can withstand five falls from an 80 kilogram climber
- with a fall factor of 1.75
- and absorb an impact force of 12 kN on the first fall
- Under static load, the rope can elongate by 10 percent under the weight of an 80-kilogram person
- On the first “norm fall,” it stretches by a maximum of 40 percent.
In today’s technologically advanced world, normal falls are not considered sufficiently realistic. If the sheath is separated by one percent, it is the maximum permissible minimum displacement.
Half ropes are 8 to 9 millimeters in diameter. Double ropes are sometimes called half ropes. This is due to their two rope lines, on which two climbers can secure themselves. Each climber then uses his own rope. The lead climber must take into account higher forces. To secure himself, he uses two half ropes. As a result, one half rope strand is alternately attached to the intermediate backups in order to reduce friction.
A twin rope is a 7 to 8 millimeter thick rope that can only be used as a double strand. Their main use is on long routes where there are good intermediate safety points. These could also be used on the way back. Here, twin ropes of two thinner diameters are used. However, they cannot support a falling load. Climbers typically use half or twin ropes in alpine regions. Half ropes are slightly heavier than twin ropes, which must withstand 12 standard falls in the test and carry 80 kilograms. Twin ropes must withstand 12 standard falls in the test. A rope must pass the fall test with five standard falls if the drop weight per strand is 55 kilos. For abseiling, two half ropes must be knotted, as otherwise only half the rope length would be available. As described above, double rope techniques were once performed with two single ropes. To know more about the difference, check out this article.