Mutual insurance for climbers. Climber's Dictionary. Terms Connection for mutual belaying of several climbers

Experienced hikers and climbers know that often only the presence of a rope and special equipment can make the route accessible and relatively safe to pass. Most trekking routes around the world allow you to navigate them without using a rope. Sometimes, in dangerous places on the routes, special cables, brackets or railings are secured.

In such cases, a helmet, protective gloves, and sometimes a harness and lanyards are sufficient for safe movement. This equipment has already been discussed in previous articles.

But on difficult hikes or climbs, rugged terrain may require more equipment. First of all, this is a rope and means of descending and ascending along it, as well as everything necessary for insurance. In this article I want to talk only about the most basic points that will make it easier for a beginner to take his first steps in the world extreme tourism, especially if he does them without detailed training by an instructor. After all, it often happens that tourists are faced with the use of such technical means on commercial climbs, where one guide/instructor for several people does not have the opportunity to provide quality training.

Rope

Depending on the possibility of use, there are two types - main And auxiliary . Main rope is used for:

1. insurance,
2. hanging railings,
3. with its help, participants move in places with difficult terrain.

Auxiliary rope (rep cord, paracord) is used for:

1. bivouac organization,
2. on the construction of crossings,
3. insurance of personal belongings and equipment,
4. insurance of participants by making the so-called prusik (Prusik knot),
5. rescue operations and other situations.

For both types of use it is better to use only certified products whose performance meets or exceeds what is required in each situation. This rule is must be strictly observed for all applications related to the safety of participants.

The main rope is of two types - dynamic(“dynamics”) and static("statics").

Dynamic rope manufactured in such a way as to stretch significantly under significant load. In this way, smooth shock absorption is achieved. The invention of dynamic rope has greatly improved world safety. extreme sports. The person using it suffers significantly less damage from a violent fall than when using a static rope.

It should be understood that stretch rope also has its disadvantages for certain types of use, primarily as vertical or horizontal railings, tension crossings, and lifting heavy loads. The “elastic band” effect makes using the rope in such cases inconvenient. In addition, dynamic rope is not a cheap pleasure.

In such cases it is irreplaceable static rope. Commercial routes to the world's highest mountains, such as Everest, install kilometers of rope ropes every year. As a rule, from static ropes. They are more convenient, cheaper, and have very high wear resistance. Rope railings are also used when hiking Elbrus, its highest, western peak.

All types of ropes now have a strong, wear-resistant upper braid, and inside they consist of a large number of durable fibers. The braid is usually made in bright colors. If you need several ropes, use different colors to avoid confusion. The condition of the rope must be carefully monitored; in the mountains it can become damaged due to exposure to aggressive environmental factors and human factors. The instructor must assess the nature of the damage to the rope. For a beginner, it is better to immediately abandon the idea of ​​​​using a damaged rope.

Today the average diameter of the main rope is about a centimeter. This thickness provides a balance of strength and wear resistance on the one hand, and weight, compactness and ease of use on the other. In the last decade there has been a slight trend towards reducing the diameter of dynamic ropes. However, a single main rope is rarely thinner than 9mm.

Belaying with a rope

The points related to self-insurance were considered. On difficult terrain, self-belaying alone is often not enough. Then the group is divided into bundles, in which the participants belay each other with a rope, being tied by it.

Insurance can be simultaneous or alternating.

Simultaneous insurance used on relatively simple, but potentially dangerous terrain. The most common example is traveling in a team on a glacier. Participants all move at the same time, while they are tied together with a rope and are at a safe distance from each other - on average, 15-18 m. If one of the bundle suddenly falls into a crack, he is delayed by the weight of the other people in the bundle and the resistance of the rope cutting into the edge of the crack. Also, simultaneous belaying is widely used on narrow dangerous ridges, where it is possible to lay a rope separating the participants behind the protrusions of the relief. Sometimes, for simultaneous belaying, artificial points for securing the rope are used, which requires more serious skills.

Variable insurance used where simultaneous movement of participants becomes dangerous. In this case, one of the participants moves along the terrain, if possible, threading the rope through the belay points (if any), and the other carefully belays him. Typically, a safety device is used. The belayer carefully watches the partner in the rope moving along the terrain, gives out the amount of rope necessary for free movement or chooses the slack.

The insurer must be ready at any time to take all measures to detain the failed first number.

This is the so-called " bottom belay", since all points of reliable fastening of the rope are below the climber. Moving with bottom belay the most risky and requires good preparation.

After the first number has advanced along the terrain for the entire length of the rope or to a convenient/arranged place, he stops and organizes a base station at reliable belay points (large stones, teeth, stationary hooks or staples, mobile belay points) and prepares to receive the second number to yourself, providing him top belay.

Top belay more reliable and less traumatic due to the fact that in the event of a breakdown (if the process is properly organized), there is no significant fall of the failed participant. In this case, the belayer can be relative to the climber both at the top (during ascents) and at the bottom (during training). In this case, the rope must pass through a special ring or carabiner at the top of the route.

Railing insurance. Railing.

It is necessary to mention this type of insurance, which is very popular on commercial and sports climbs, and is considered group insurance.

By railing, as a rule, we mean a rope fixed on both sides (top and bottom), which often also has additional fastening points along its length (this is especially true for horizontal or diagonal railings). Such points of additional rope fastening are required at the bends of the railing path.

People usually move along the railings by clipping a lanyard into them using a carabiner (link) if the terrain is simple. If the terrain is difficult for the climber, then special clamps are used to prevent slipping down. The simplest and most accessible clamp is Prusik knot(cm.

Belay devices

Reliable alternate belay requires the use of special devices. Currently, a great variety of them have been invented. The main types will be discussed here, each of which has its own advantages and disadvantages.

You need to understand that only the most affordable and popular devices for use on hikes are described here.

Knot UIAA (UIAA). This abbreviation stands for “International Mountaineering Federation”. It is the standards of this organization that are taken as the basis for the certification of almost all devices for extreme activities. The UIAA knot is perhaps the simplest method of relatively safe insurance. It can also be used for rappelling. All you need for this is a reliable carabiner, preferably steel, with a round cross-section (a carabiner made of a light alloy will begin to wear out quite quickly). This knot works “in both directions”, has two positions, in one of which the rope easily extends through the carabiner, and in the other it offers great resistance to passing through it.

Basics advantage This method of insurance is simplicity.

Disadvantages more. The main one is that the knot twists the rope very tightly, which after just one passage through the carabiner with the knot becomes unsuitable for further use without alignment. Therefore, this method should be known rather “just in case.”

« Eight" This type of descender is very simple and reliable to use. Still would! There is simply nothing to break here. In addition to the eight, you also need a carbine.

Basic dignity- lightness, simplicity, cheapness. The ability for most designs to work with double rope, with thick, stiff or very dirty rope that may "refuse to cooperate" with more delicate devices.

From shortcomings- “twists” the rope, although not as much as the UIA knot. Requires increased care in use, as it does not have a self-blocking effect. A certain paradox occurs - a device that requires precise skills and is potentially one of the most dangerous, most often ends up in the hands of beginners due to its low cost...

« Cup" A technically more advanced group of devices. Just as light and almost as simple in design as the eights, but with a partial self-locking effect. There are many designs for double rope. Ideal devices? If only... They do not work well with rigid ropes and ropes of increased diameter...

Many homemade or original devices from small-scale manufacturers work on a similar principle to the glass - all kinds of “bugs”, “fungi”, “swallows” and other works of unstoppable engineering.

The devices listed above are convenient in that they can be used with equal success both for belaying and for rappelling. At the same time, they are light in weight, compact, cheap and best suited for beginners. Still, it’s hard for me to recommend the figure eight as the first belay device for a beginner.

There are a number of more bulky and specialized devices, used mainly in industrial mountaineering and speleology. They are characterized by bulkiness, significant weight, and high cost. Therefore, they are more suitable for professional use and will not be discussed in this article.

I cannot ignore another iconic safety device, which, however, can be used to a limited extent for descent - gri-gri (GriGri) from the famous French equipment manufacturer Petzl. Over time, the principle of operation of the device was borrowed by other manufacturers with varying degrees of success.

First of all, the device is popular among rock climbers and mountaineers. Its feature is semi-automatic operation. The operation of the device is somewhat similar to the action of inertial seat belts in a car - if you pull smoothly, the rope (belt) extends freely, but if you pull sharply, the mechanism is blocked. True, there are some nuances in using the device. However, it significantly increases the security of insurance. Unfortunately, limited use, high price (about $90) and the need for certain skills do not make this device best choice for a beginner.

Also worth mentioning separately Prusik knot . This ingenious invention is already more than eighty years old and, despite significant advances in technology during this time, it is still widely used in mountaineering, tourism and other types of extreme activities. This knot is a type of noose - a type of grasping knot that has a pronounced self-blocking effect (with correct use). Allows the climber to linger in the event of an unexpected fall. At the same time, it is very simple, weighs almost nothing and takes up exactly the same amount of space as a two-meter cord, from which it is most often made.

I believe that the reader understands that any information in any of the most excellent articles is just food for thought. It cannot be the only reason for using special equipment in extreme travel or other circumstances. I highly recommend practical training in the types of extreme activity you are interested in with a knowledgeable instructor. It also makes sense to conduct potentially dangerous hikes under the guidance of an experienced guide or people who have the necessary skills to perform more difficult activities than those required by the activity.

I wish you exciting, eventful, but safe adventures! The one who walks will master the road.

insurance
Self-insurance
Railing
Mutual
Spot
Horizontal
Variable
Simultaneous
Upper
Vertical
Static
Dynamic
Lower
Static
Dynamic

Self-insurance

Mutual insurance

Spot belay

Railing insurance

Variable insurance

Top belay

Bottom belay

10. Bottom rope

11. Jerk Factor

12.

13.

We are a large portal that combines an online casino, a poker room and a bookmaker's office! We are under the jurisdiction of the Government of Malta. Our gambling house offers real guarantees of reliability: Thawte and IBAS certificates - the latter was issued to the bookmaker by the UK Gambling Commission. Each player is entitled to a registration bonus - create a personal profile and start playing for money!

Registration and login - everything guests of Bet365 need to know

Mirror - bypass casino website blocks easily

• browser plugins;
• proxy servers;
• VPN services;
• alternative sites.

Bonuses and promotions - get extra motivation to play at Bet365

• money to the account for account registration;
• additional accruals of funds on first deposits;
• a chance to win free spins every Monday when you deposit 20 euros or more;
• 25% cashback for the first 10 games of blackjack;
• various benefits with promotional code;
• up to 100 euros for all new users to play roulette;
• gifts for winning tournaments and lotteries.

How to play for real money?

• virtual slot machines;
• Bingo;
• roulette;
• different kinds poker in a special room;
• black Jack;
• baccarat;
• Sic-Bo and other emulators.

Withdrawing winnings from your Bet365 gaming account

Mobile version - use the site on any device

• launch slots and Board games;
• withdraw earnings;
• replenish the deposit;
• receive bonuses;
• participate in tournaments and lotteries;
• contact technical support.

.. 21 22 23 ..

Mutual insuranceclimbers

Mutual belay is the basis of mountaineering safety. Mutual insurance aims to hold on to the partner who has fallen off the hook with the help of

rope connecting them to each other. It can be simultaneous (with the simultaneous movement of the entire team) and alternating, when only one person from the team moves, and the rest, having secured themselves in place, belay him by giving out or choosing a rope.

Movement of climbers in a chain in a bundle

When belaying at the same time, a team of two or more people can move in a chain (in the direction of the rope connecting them) or in a line - parallel tracks. The first method (Fig. 20). used when moving on a closed glacier, along simple ridges and cornices, on not particularly steep snow slopes with loose snow (self-holding is more reliable on it). Everyone in the bunch, except for the one in front, must have a rope reserve - one or two loops (1-1.5 m) held in the hand, in order to avoid a sudden jerk in the event of a breakdown or fall of the person in front, as well as to compensate for the difference in speed that sometimes arises promotion. During such an advance, the last one in the group, who cannot be followed by his comrades, should be especially attentive. The distance between partners can be, depending on the specific conditions of the route, from 7 to 12 m. The features of this method of insurance in relation to various forms of mountainous terrain will be outlined in the corresponding section.

The second method is used mainly on descents on firn and snowy (not avalanche-hazardous) slopes with a steepness of up to 40°. A pair of two, tied with a rope, at a distance of 4-8 m, descends or rises in front, at the same level. Sliding during a fall in this case occurs with a “pure pendulum” and it is quite possible for the ice ax to self-braking, so holding on does not cause any great difficulties.

Alternating belay for climbers

Alternating belay is used when simultaneous belay is not reliable enough (on steep sections of the slope and objectively dangerous places).

It can be upper or lower, depending on the location of the belayer in relation to the insured (if the belayer is lower, the insurance is lower, and vice versa).

The organization of the top belay, either in terms of technical support or reliability, does not pose any particular difficulties.

The belayer must carefully ensure that the rope between him and the besieged does not have significant slack. Then, during a fall, there is no dynamic jerk and the belayer must only support the weight of the partner. At making the right choice The position of the belayer and timely reaction in this case, holding the rope is quite simple.

With alternating belay, the most rational combination is a two-piece: it ensures maximum speed of movement, efficiency of working with the rope, and convenient placement in dangerous areas. The triple is more reliable, especially when moving along a closed glacier or cornice ridge, but the speed of movement in this case is significantly lower than that of the double.

In English-language sources, the requirements for insurance stations are often denoted by different abbreviations - SRENE, EARNEST, IDEAL, etc. The essence of them all comes down to a few general principles:
· Reliability of all elements (points and ligament material);
· Redundancy - elements must be duplicated;
· Leveling - the total load on the station should be evenly distributed to all points;
· Failure of one of the points should not lead to a large “subsidence” of the entire station.

Of course, compliance with all the rules is just an ideal to which we must strive. Real conditions are too diverse and do not always make it possible to fulfill absolutely all requirements. However, the options discussed below may help you choose the best alternative.

Some advice from Cyril Chocopleux, President of the Canadian Mountain Guides Association:
“When organizing stations, the influence of the reliability of each individual point on the reliability of the system as a whole is often overlooked. A retrospective analysis of accidents gives cause for concern. Suffice it to say that several people have died and many others have been injured by ignoring the recommendations below.

1. Do not rely on using communications from unreliable points for your main station. Use the biggest and strongest tools you have and make sure your points are placed in solid rock. Small and medium primary points are much less reliable than large ones. Trying to distribute the load across several weak points gives you a weak station. Don't rely on equalization or load sharing alone. Use strong primary points whenever possible.

2. Place a reliable point close to the station. Don't consider it just one of many intermediate points. In fact, it is an integral part of your belay station. Several years ago I witnessed a climber fall directly onto the station. The station was completely destroyed and the entire bunch flew 200-300 meters down the couloir. Both survived miraculously, although they received serious injuries. A reliable first waypoint might have prevented the destruction of the station entirely.

3. Do not use a daisy chain for self-belaying - it is not a safe practice. Daisy chain is a relatively static component. Several accidents in the US and Europe have been directly linked to the use of daisy chains as a primary means of self-insurance. All daisy chain manufacturers warn against this. Tests showed clear gaps during very short drops on the daisy chain. It is also very easy to mistakenly use a daisy chain in such a way that even the slightest load will cause the lanyard to fail completely.

4. Many tests have confirmed that nylon cord with a diameter of 7 mm is the optimal material for most types of climbing stations. It provides good dynamic qualities, has better resistance to sharp bends, is durable, and is quite strong. Most new high-tech fibers do not have all these qualities, especially in the area of ​​dynamic loading. They are less durable and perform worse on sharp rock edges. Despite their high overall strength, the new fibers can fail you in certain situations.

5. Remember that the jerk of a fall is not necessarily vertical up and down. Carefully consider the possible directions of the jerk and arrange the station accordingly.

Station at a single point.

Use of natural relief elements.

We just mentioned duplication of points as one of the main requirements for a station. Are there cases when we can organize a station at a single point? Any experienced climber will tell you “yes”! However, you need to think carefully about the following things:

·Is this a reliable item? If it is a large tree trunk, shake it: is it sitting well in the soil, or is the tree ready to fall? Is the tree alive or dry? If it is a rocky outcrop, push it to see if it moves? If it's a large boulder, rock it a few times to make sure it doesn't slide down with you and your partner.

Are you sure that the direction of thrust will be as it should be? Could too much load be applied to this point? Are you making a station for descent or for belay when ascending?
·How high is the probability of a failure and what will happen if a failure occurs?

·Do you have enough experience to correctly assess the situation?

An experienced guide or climber may be able to arrange a belay on a single hook or anchor in some situations, but only after careful consideration of the above factors. Don't think that single point insurance has to become your norm! This should be the exception on a difficult technical climb.

The most obvious example of a single point station is a tree. To reduce leverage, in most cases it is better to mount the station lower on the barrel.

Rice. 1. Fastening with a noose. (Girth Hitch)

The noose knot around a tree (Fig. 1) is often used in practice, but in fact it is not The best way fastening. In all likelihood it will withstand an average drop, but it does create a higher load at the point where the line passes through the loop than would be desirable. In fact, we get a mini pulley, which increases the load on the loop, especially if fastened carelessly. The load is distributed only on two threads of the loop. Let's consider alternative methods.

Rice. 2. Fastening with a double loop.

In Fig. 2 good idea spoiled by poor execution. The loop used is too short. The result was a large angle between the branches of the loop and a large load on the loop itself. If you move the carabiner, there is a risk of loading it in three directions - fig. 3. With such a load, the strength of the carbine is about a third of the nominal.

Rice. 3. Dangerous position of the carabiner.

Rice. 4. Fastening with a long double loop

Rice. 4 - we used a longer loop and got a smaller angle between its branches and a distribution of the load across the four threads of the loop. The ideal angle in this situation is about 25 degrees. This reduces the stress on the loop and carabiner and also reduces the likelihood of stressing the carabiner in three directions. To further reduce the risk of incorrect loading, a special carabiner is used.

Rice. 5. Double loop with a knot.

Rice. 5 - the loop goes around the tree and is tied with a figure eight knot to create a belay point. This eliminates the problem of loading the carabiner in three directions. The disadvantage of this method is that it is difficult to untie a knot that has been tightened under heavy load in order to remove the loop. To make untying easier, a carabiner can be inserted into the knot, as shown in Fig. 6.

Rice. 6. Carabiner in the central point of the station.

The carabiner in the knot is a good point for a lanyard, leaving the center point free for you to belay through the UIAA knot or lanyard your partner when they approach you. Be sure to insert the carabiner into the knot before it tightens under load.

If you still forgot to do this and still want to get two separate items, you can use the so-called “shelf”, as shown in Fig. 7. Separate one strand of the loop and snap the carabiner into the remaining ones. A carabiner attached to a rack may not be loaded correctly, so do not use it to secure a partner.

Rice. 7. A carbine in the shelf of the central point of the station.

In rare cases, it may be useful to use all three points at the same time - fig. 8. Just don’t confuse their purpose.

Rice. 8. Auxiliary carbines at the central point of the station.

Rice. 9. Loop with an extra turn.

In Fig. 9 shows a very reliable, but too labor-intensive method for use on regular ascents; This option is good for rescue situations. The knot is effectively removed from the point of application of the load, the load is distributed over the four threads of the loop. The angle between the branches of the loop is small, the safety carabiner is loaded correctly.

Rice. 10. Ledge Station

Make sure the lip is large enough and secure. Test it by kicking and tugging it a few times. Make sure the loop does not slip off the tab. A good, strong sling will work better than a cord in such cases, since the cord may roll off the rock while the sling may remain in place. Over the past 25 years, in the collection “Accidents on ascents in North America» At least six cases of failures were noted during rappelling using a rappel station on a single ledge. When descending, a load of up to 3.5 kN can be placed on the point. Loads from failures during lifting are much greater!

Rice. 11. Use of rock spalling.

Breakaways are a standard belay point for classic mountaineering routes. When used properly, they provide quick and safe belay points for both ascent and descent of a rope. As with boulders, they should be carefully checked before use and, if required, supplemented with other points. Belay points on ledges and breaks usually work in one direction and for a full station should be used with additional belay points. A sling loop is preferable to a round cord in this case as well. The sharp edges of the rock can cut your loop when jerking - be careful! Try to make the angle between the branches of the loop smaller (do not use loops that are too short).

Rice. 12. Point on a stone plug.

Large rocks sometimes get stuck in cracks and are called plugs. After proper testing, the plug can also be used as a belay point. Sometimes, it is possible to create an artificial plug by wedging a suitable stone into the appropriate crack, as shown in Fig. 12. The option in this figure cannot be used as a single station point because it only works well with a downward load.

Rice. 13. Belay point on the hourglass

Sometimes, the natural features of the rock allow a loop to be threaded through a natural opening or tunnel to provide a belay point. In this case, the recommendations made above regarding hinge material, the need for reliability testing and the danger of sharp edges are valid. Shown in this fig. 12 point is not suitable as a single point for a station, but can be used as part of a multipoint system to organize a reliable station.

Here is a brief overview of the use of techniques for organizing belay stations on natural elements of the terrain using an auxiliary cord (“cordelette”) or lanyard loops (“slings”). Of course, the techniques shown are also suitable for use in multipoint stations, which will be discussed later.

Loop lengthening

Often the length of the loop is too short and in order to create a good belay point, you need to connect several short loops together. The use of nodes in this case is not always justified.
In 2006, tests were carried out in the Black Diamond laboratory in various ways tying slings. 17mm nylon, 10mm and 8mm Dynex slings and 6mm Dyneema slings were tested, tied in various combinations with choke, straight and climber knots.

Rice. 14. Tested types of loop connections.

General conclusions: the material, size of the slings and their combination have a greater influence on the overall strength than the type of knot. When tying a wider nylon sling with narrow slings made from high-strength materials, the overall strength is reduced by almost half. When tying narrow slings made of dynema and dinex, the overall strength was also about 55%.

Table 1. Results of static tests. Relative strength of connected slings.

Table 2. Results of dynamic tests for the noose node

Even elongation without a knot reduces the overall strength by 40%. The overall strength of such a connection is on average 15.8 kN. (nylon loop strength - 25.5 kN).

Rice. 15. Extension without a knot - “loop in a loop.”

Similar results were obtained when testing slings at Mammut in 2007.

In many cases, a strength of 10-15 kN is quite sufficient, but if we need maximum strength, it is necessary to use carabiners to connect sewn loops.

In many situations, to build a station, two reliable points are enough - two strong hooks, ice screws, anchors, etc. There are many ways to block these two points.

Using tie rope to block points

Rice. 16 Consecutive connection of two points with the main rope.

In Fig. Figure 16 shows a diagram of a serial connection between two points. The method is simple and fast, but requires reliable belay points, for example, anchors on equipped multi-pitch routes. The entire load in case of failure falls on only one hook, the second one secures it. To reduce the load on the point, good knowledge of dynamic belay techniques is necessary. Daisy chaining of points is often used in combined multipoint station configurations, which will be discussed in part three.

Rice. 17. Using the main rope of the bundle to “parallel” connect the points.

You can also use a ligament rope to organize a parallel connection of points so that the load is distributed between several points.

In Fig. 17, the right branch of the rope goes to the second in the bundle, the branch in the center, below the knot with the carabiner, is the lanyard of the first.

Rice. 18. Using the main rope of the bundle to “parallel” connect the points.

In Fig. 18 is another option. A node is used to connect two points. The rope on the left goes to the belayer standing at the station. The safety carabiner is tied with a stirrup knot. The top belay of the climbing partner is through the UIAA knot. In these variants, both members of the link are connected to the central point of the station.

Independent hinges

You can use two independent loops only if when you are firmly confident in the direction of the expected load and are limited in the choice of equipment . For good load distribution, loops of appropriate length are needed. An example station using independent loops is shown below.

In Fig. Figure 19 shows two reliable points that we want to connect into a simple station for our partner’s top belay.

Rice. 19. Using guy ropes to block points.

Because collarless carabiners are used here, the carabiner latches at the center point must be positioned opposite each other. We attach our lanyard and prepare to accept a partner only if we are sure that the load will be directed at the right angle. If this is not the case, we must correct the situation before moving forward.

In the same way, you can use separate loops instead of guys.
This is a quick and easy solution as long as your two points are secure and you eliminate the possibility of the carbine being loaded in three directions. To prevent such situations, combine the two loops with one common knot, as shown in Fig. 20.

Rice. 20. Combining two loops with a common knot.

Another way to join is to pass one loop through the other knot, as shown in Fig. 21. This can be done with both cord and sling loops, just be careful not to destroy the integrity of the knot. Which method is best will have to be decided on the spot. Try not to overcomplicate station configurations, as this is often time-consuming.

Rice. 21. Option for combining loops.

When using a single long loop, pull it in the direction of the expected load to manually equalize the load on both points, then tie a knot to create independent loop branches - fig. 22. This reduces the chance of a large subsidence when one of the points leaves, but evenly distributes the load on the points only if you have not made a mistake in the direction of applying force to the station and the branches of the loop are of equal length.

Rice. 22. Joining two points with a long loop.

Another option is to tie a knot approximately in the middle of the long loop, snap the ends of the loop separated by the knot into the point carabiners and attach the center point carabiner, as shown in Fig. 23.

Rice. 23. Option for combining points.

On climbs we are limited in the choice of loop lengths for stations. Lengthening the loops has already been discussed in the first part. If you use a standard cordelette loop about 3 meters long to connect two points, it is often necessary to shorten it. The easiest way is to fold the loop in half, snap the ends of the loop into the carabiners at the points, equalize the tension of the branches and tie a common knot, as shown in Fig. 24. If the loop turns out to be too short, you can shorten it not by half, but by one third - fig. 25.

Rice. 24 Shortening the loop by half.

Rice. 25. Shortening the loop by a third.

Rice. 26. Shortening a loop to an arbitrary length. A less reliable way is to tie a conductor (regular or “butterfly”) on one “thread” of the cord, as shown in Fig. 26.

The methods of blocking two points discussed above create branches of a fixed length, converging at a common node of the central point. This has its advantages and disadvantages.

Advantages– insensitivity to the rupture of one of the branches of the loop and low subsidence in the event of tearing out one of the points or breaking the cord.

Flaw- one, but very significant - poor distribution of the total load on the points. Such stations, firstly, are very sensitive to the direction of the load. With deviations of more than 10 degrees, almost the entire load falls on only one of the points. Secondly, the load distribution depends not only on the angles between the loop branches and the direction of the jerk, but also on the ratio of the lengths of the loop branches. Even in a system with ideal pre-leveling of loop tension, under the influence of a strong jerk more short branch(and the corresponding point) will be loaded more strongly than the longer one - fig. 27. In tests done at Sterling Ropes, the difference in point loads was 3.5 - 5 kN (see Appendix 2). For this reason, this method of connecting points is less suitable if the points are located at a large vertical distance.

Rice. 27. Load distribution across points in a fixed loop.

Compensation loop blocking

This system is also called “equalizer”, “sliding knot”,
“sliding or magic crosshair” (sliding-X, magic-X). This blocking is used when the direction of the load can change within large limits or when the direction of the jerk cannot be predicted in advance. Often this method is used to combine two weak points in combined multipoint stations.

Rice. 28 Obtaining a compensation loop at two points

By making a half turn on one of the two loop areas, we get a station that:
— evenly distributes the load on both points when jerking in different directions
- distributes the load across four strands of cord
— in case of tearing out or destruction of one of the two points remains operational.

The final position of the central carabiner depends on the direction of rotation of the loop on the cord - fig. 29.

Rice. 29. Position of the carbine at the central point.

Loop knot position

When organizing the station, it is necessary to take into account the position of the node connecting the cord into a closed loop.
If the station points are at different heights, the station blocking triangle has a short and a long side. The loop assembly should be on the short side of the station lock. (If the loop reversal is not blocked by an additional point – approx. lane). If the loop turns upside down (a fall with intermediate safety points), the short side of the locking triangle lengthens and the knot does not get stuck in the safety carabiner. If the knot is located on the long side of the triangle, when the loop is turned over, it prevents the distribution of the jerk force to both points of the station - fig. thirty.

Rice. 30. Position of the connecting unit when overturning the blocking.

In the pictures above, loops were used that were previously tied with grapevine or counter knots. Another method of knitting a compensation loop is also possible - fig. 31:

Rice. 31 “Italian” compensation loop.

Attention! The length of the ends coming out of the knot is at least 10 cord diameters! For a 7mm cord – at least 7 cm.
Since this is a “signature dish of Italian cuisine,” I will call this method the Italian loop.

Advantagesthis option:
·The loop connecting point is always located at the central point of the station. In the event of a “tipping over” of the blocking (the first one falls in the presence of intermediate safety points), in contrast to the classic version of the compensation loop, there is absolutely no risk of the connecting unit getting stuck in the station’s carabiners.

·Having a fixed node at a central point provides a more convenient point for placing multiple belay and lanyard carabiners.

·The knot is knitted faster and easier than a grapevine or counter knot, which saves time when organizing a station if you use a piece of cord rather than a finished loop.

·This option is also suitable in the case of organizing a station for descent with pulling a double rope. In the event of one of the points flying out, the descending rope is clamped in the remaining loop much less than in the version with a conventional compensating loop - fig. 32: on the left is an Italian loop, on the right is a regular one.

Rice. 32. Imitation of tearing out one point when descending on a double rope.

General disadvantages of stations on a compensation loop:

First drawback – no redundancy in the loop. When the loop breaks, for example, on a sharp rocky edge, is interrupted by a rockfall, or a knot is untied, the entire station completely disintegrates. Such incidents have occurred several times during rappelling with fatal consequences, as noted in the collections of Accidents in North American Mountaineering.

Second drawback – the loop overlaps on the central point carabiner. At the same time, the equalization of the load on the points due to friction worsens. For this reason, flat lines perform worse than round lines in a compensation loop.

Third drawback – when one of the points flies out, the loop extends over a relatively large distance and a large impact load may fall on the remaining point (see also Appendix 2). Even if one of the points remains in place, unexpected subsidence can cause the belayer to lose balance or fall and lose the belay of his partner. Therefore, the length of the locking loop should not be excessively increased.

To reduce these disadvantages of expansion loops, limiting nodes are often used.

Restrictive nodes on the compensation loop.

Rice. 33. Compensating loop with limiting nodes.

These two nodes on the branches of the compensating loop greatly reduce the possible elongation of the loop when tearing out any of the points, while maintaining the benefits of load equalization.

By changing the positions of the nodes, you can adjust the actual range of directions in which alignment occurs. Let's look at possible failure scenarios.

If the loop breaks for some reason, we get an extension of the loop by several centimeters and the second part takes the entire load upon itself.

If one of the points flies out, the loop lengthens by several centimeters and the entire load falls on the second point.

In cases where one branch is much longer, a single limiting node can be used - Fig. 34.

Rice. 34. Compensation loop with one limiting node.

Due to friction, the compensation loop distributes the load far from ideally, especially during dynamic jerks. To reduce friction, John Long, in the new edition of the book “Climbing Anchors,” proposed the idea of ​​​​the so-called “Equalette” (Fig. 35. The results are much better (see Appendix 2), but alas, this requires two separate coupling carbines.

Rice. 35. Two carabiners at a central point - the “equalette” method.

“Quad” option – allows you to use only one carabiner at the central point while shortening the useful length of the loop by half – fig. 36.

Rice. 36. “Quad” - restrictive knots on a double loop.

The same principle with less shortening is shown in Fig. 37

Rice. 37. Another option is “Quad”.

Another option is to tie an additional sling - fig. 38

Rice. 38. Additional sling at the central point.

The third option - restrictive knots are tied so that the loop sections between them have different lengths- Rice. 39. The longer section of the loop is used to secure the carabiner. Here it is also permissible to use one carabiner at a central point.

Rice. 39. “Equalette” variant with one carabiner at the central point of the station.

Naturally, when the blocking is overturned in the event of a fall with intermediate safety points, the limiting nodes can interfere with the distribution of the load on the station points, so you need to take into account the future location of the first intermediate point, or prevent overturning by an additional point designed for an upward jerk.

Errors when joining two points

Rice. 40. Incorrect blocking of points.

The central point carabiner in Fig. 40 is simply hung on a loop and if one point fails, it flies off it.

Rice. 41 "Deadly Triangle"

·- The load is distributed only over two “threads” of the cord
·- Due to the pulley effect, a tightening force acts on the points.

Appendix 1. Strength of various locking methods.

For reference, here are some hinge strength test results:
Colin Powick from Black Diamond compared the strength of three 120cm loop point blocking options. Results:

Table 3. Strength of different point blocking options.

Test results of the “Italian loop” according to CAI:

Table 4. Strength of the “Italian loop”

For comparison:
·Standard strength of the loop (“sling”) – 22 kN
·Standard strength of the carabiner – 22–25 kN
·Strength of bookmarks, friends, camalots – 5...10 kN (small and medium sizes).

Appendix 2. Efficiency of load balancing at station points.

Dynamic testing at Sterling Rope was carried out by Jim Ewing, John Long and others. Point-to-point station options with branches of equal and unequal length were tested. The test load was dropped on a dynamic rope with a fall factor of 1 and the peak loads at each station point were measured. For unequal-armed configurations, the branch lengths were 45 and 100 cm. Some results are shown in Table 5.

Table 5. Load distribution at two station points for different blocking options.

Explanations:
Load on points (Arm load) is given in kN,
“Cordelette unequal” - the loop is connected by a common knot, the branches have different lengths - the configuration shown in Fig. 27 on the right,
“Sliding X unequal” – compensation loop with arms of different lengths,
“Cordelette equal” - the loop is connected by a common knot, the branches have the same length - the configuration shown in Fig. 27 on the left,
· “Sliding X equal” – a compensation loop with branches of the same length.

The absolute spread of loads on points in tests and the relative efficiency of load equalization on station points are shown in the graphs - Fig. 42 and 43 respectively. (equalette unequal - the method shown in Fig. 35, the branches have different lengths).

Rice. 42. Dispersion of point load values ​​for different station options.

Rice. 43. Comparative efficiency of load balancing of different station options

In the tests carried out, the tearing out of one of the points was also simulated. Wherein for compensation loops with limiting nodes, no increase in the peak load during “settling” by 15-20 cm was recorded. It should be emphasized that in the tests, to attach the load to the station, it was useddynamic rope!