Carabiners

Basic part of carabiner is its body. Other part of the body is nose and a notch. Carabiner is closed by a gate, ensuring that the rope does not slip out of the carabiner by itself. In most types of carabiners must be the gate closed automatically (not carabiner type A and Q), revolves around the first axis. On the other hand, the purpose of the second axis (sometimes cast together with the gate) is to fit in the notch after closing of the carabiner. This is necessary because the carabiner’s body is flexible and after applying a force slightly expands. So second axis (pin) after a load leans into the notch, fully showing the effect of a closed circuit, which is stronger. The safety lock is used to prevent spontaneous opening of carabiner after its closure. Some types of carabiners must be compulsorily equipped with a safety lock.

If the carabiner is fitted with a key-lock system its nose has a different shape. Carabiner with a wire lock does not have axes, first axis is part of a gate and second axis is not necessary, because the nose is hooked directly into the wire.

General carabiners requirements: Depending on the type the carabiner must meet load capacity requirements and shall be fitted with mandatory markings.

Marking

Each carabiner must show the basic information: Load capacity in longitudinal and cross direction and load capacity with open gate. According to the latest standards must be the strength specified in kN, in older types we can also meet with other units:

kN, 1 kN … 100 kg; daN, 1 daN … 1 kg

A number stating load capacity is actually a breaking strength, when the carabiner snaps (not the value of the regular load). Value should be an integer (in kN) rounded down. According to standard ČSN EN 12275 must be the type of carabiners H, K and X marked with a particular letter in a circle.

Types of carabiners

Carabiner types and their required minimal static strength. First column specifies type designation according to standard CSN EN 12275. Second column specifies the designation used in mountaineering literature, which is in some cases different (watch for substitution of types D and B). If the carabiner is equipped with auto-lock no requirements are needed for the data marked with an asterisk.

Continued in the book >>

iPhone, iPad, Mac
Android, web browser
Kindle Fire
Kindle e-ink