Mounting the cable on the pole project. Lanyard is a useful device with an unusual name for working with heavy objects. Junction boxes and cable-mounted lighting fixtures
Earrings, thimbles, carbines, lanyards - most of us rarely have to deal with such specific objects and, probably, not everyone knows about their existence. Therefore, information about what is hidden behind these mysterious terms will not hurt anyone. So, in this article we will talk about rigging accessories. And you have to meet with them whenever there is a need to lift, fasten, pull or hang something with a wire, cable or rope.
Having professional rigging equipment at hand, many tasks can be solved many times easier and more efficiently than with the usual improvised means. You can buy everything that is necessary to perform these works today in almost any construction market.
Cable clamps will allow you to securely fasten the whips when forming loops at the end of the cable, and lanyards - to pull the cable with any necessary effort.
Talrets
The most famous and commonly used device for tensioning cables is a lanyard - screw stretching device. It is arranged very simply and usually consists of three parts: two screws and a housing. The cable is pulled with a lanyard by rotating its body.
One of the screws has a right-hand thread, the other has a left-hand thread. Therefore, when the body rotates, they either screw in (they approach each other and pull the cable), or both unscrew and move away from one another, depending on the direction of rotation.
The lanyard screws can have rings (loops), hooks or forks with locking fingers at the ends, which provide a strong and at the same time easily detachable connection.
Now on sale there is a very wide range of lanyards that differ from each other in size and are designed for loads from several kilograms to 1-2 tons.
Talrets are made, as a rule, of high-quality steel and have a protective nickel or zinc coating, which allows them to be used in rooms with high humidity, and outdoors.
Yachtsmen, signalmen, assemblers are best familiar with screw tensioners. However, in domestic conditions there are many options for using talrets, for example, when installing an antenna mast and fastening it with braces, when constructing trellises, when installing fences or hanging lamps. In a word, wherever a tightly stretched wire, rope or cable is required as a structural element.
On the left - thimbles of various sizes, above them - U-shaped earrings, then to the right above and below - lanyards of various sizes and designs, on the lower right - cable clamps.
Earrings
Along with lanyards, when working with cables and ropes, it is very often necessary to use earrings - U-shaped connecting elements with a stopper (“finger”) that is cottered or screwed onto the thread. They are mainly intended for reliable and quick connection of two or more strands of cables, fastening them to lugs, brackets, eyebolts, etc.
Earrings are produced in different sizes so that they can be matched to one or another cable thickness and corresponding load. It is usually believed that the larger the earring, the greater the load it can take.
To hook a cable (rope) to a hook or secure it with an earring, you need to make a loop at its end or, as they say, “end the cable”. To do this, several types of special easy-to-assemble clamps of various sizes are produced (in photo 2 - at the bottom right). Usually, the diameter of the cable for which this or that clamp is designed is indicated by the marking on its body. Photo 1 shows several examples of cable termination with clamps various types.
Koushi
The above examples of loop formation are designed for not too high loads. For cables that experience very high tensile forces (for example, when towing cars or moving heavy items winch), the loop at the end is usually reinforced with a thimble inserted inside.
In this case, the deformations that occur during tension are not perceived by the cable itself, but by a drop-shaped loop stamped from sheet metal, due to which the cable bends less and wears out less intensively.
The thimbles also come in different sizes, designed for one or another thickness of cables and for one or another size of loops. In addition, plastic thimbles are produced specifically for terminating nylon or hemp ropes.
Carabiners
A useful addition to the devices discussed above are the so-called carbines.
Usually they are used on a par with earrings, but unlike the latter, carabiners allow you to quickly connect or disengage the connection with one click on the spring-loaded carabiner latch.
To connect the ends of a cable or rope, as well as to form loops at the ends, various types of steel, copper or aluminum clamps are used. Relating to rigging fasteners, cable clamps are used in the elevator industry, when carrying out various installation work as well as at home.
Types of clamps
To ensure durability and reliability, all structural elements clamps are made of stainless steel, and for light operating loads - also made of copper, brass or aluminum.
The most popular are:
Features of using different types of cable clamps
The main technical parameters of the products in question are the maximum diameter of the cable and the guaranteed clamping force. The dimensions of the clamp are also important, since it is recommended, regardless of type, to use several clamps in series (at least three), especially if the weight of the load does not guarantee its safe movement or lifting.
Clamps according to DIN 741 are used for ropes with a diameter of 5 ... 62 mm, in the presence of a spring washer in accordance with GOST 6402-70 and a nut in accordance with GOST 5915-70. The design of such a clamp provides for the possibility of installing a locking bar, which provides a more reliable clamping of the cable to the bracket. The clamping block must be made by stamping from steel grade not lower than St.3kp in accordance with GOST 380-94 (only for small clamping forces, cast blocks of steel 25L are allowed in accordance with GOST 977-75). It is not allowed to use cable clamps, the details of which do not have a protective anti-corrosion zinc coating.
In the fasteners of flat clamps, threads must be used in accordance with GOST 24705-81. The lining material is St.3 steel, the plates should be used for fastening cables with a diameter of 4.6 ... 30 mm.
In the case of successive use of several clamps, the distance between them should not be less than six cable diameters.
In Duplex type double clamps, the shear force is absorbed exclusively by the bolted connection, so the choice of fastener diameter is determined by the diameter of the cable. The following ratios are recommended:
- For a cable with a diameter of 2 mm and 3 mm - M4 fasteners;
- For a cable with a diameter of 4 mm and 5 mm - fasteners M5;
- For a cable with a diameter of 6 mm - fasteners M6;
- For a cable with a diameter of 8 mm - fasteners M8;
- For a cable with a diameter of 10 ... 12 mm - M10 fasteners.
Wedge clamps are not recommended for lifting loads. Because the operational loads on the fasteners are reduced, since the axes of the forces during the operation of such a clamp coincide, and, therefore, shear stresses do not occur. The operating parameters of the wedge-type clamps are regulated by DIN 15315. For screw clamping of the cable or rope to the supporting surface of the wedge, high-strength fasteners are used (strength class at least 5.6), with a protective anti-friction coating. Periodically, the connection needs to be tightened.
The barrel clamp is often made of aluminum, and is not designed for large cable diameters: the rational range of diameters is 2 ... 8 mm. The absence of protruding elements and the compactness of such a clamp allows it to be used in confined spaces.
Is it possible to make a cable clamp with your own hands?
The price of clamps, depending on their size and permissible load capacity, is, rub / piece:
- For Simplex clamps - 4 ... 14;
- For Duplex clamps – 7…24;
- For clamps according to DIN 741 - 4…160;
- For wedge clamps - 200 ... 250;
- For barrel clamps - 3 ... 40 (aluminum), and 60 ... 160 (stainless steel).
In everyday life (for example, for motorists), there is often a need to make a cable clamp with your own hands. To form a reliable loop, it is advisable to use an ordinary aluminum (not duralumin!) tube, inside which a cable of the desired diameter should freely enter. The tube is bent in an arc, after which a cable is inserted there at a distance of 120 ... 150 mm, its ends are covered with brackets, and connected with a bolt.
When building up parts of the cable, the diameter of the pipe is chosen so that both cables freely enter there, and from different ends. All other actions are performed in a similar way. It should be noted that the bearing capacity of such a cable clamp will be determined by the bending strength of the pipe material, therefore the permissible force of a home-made clamp device will be noticeably lower than that made by a specialized company.
Used by professional riggers, the word lanyard may seem unfamiliar, but at the same time, everyone must have seen this item at least sometime. For the first time, such a fastening device was used in the field of marine cargo transportation by specialists in secure cargo securing. This was the name of the device, which is also used now when tightening, choosing slack in rigging, building buildings, installing cables, poles and other supports, such as buttresses.
To understand what it is - a lanyard, get acquainted with its types, functions and concrete examples applications.
Turnbuckles of two types
Key details and design features
The turnbuckle, also known as a ratchet by experts, most often consists of two counter-threaded screws that are screwed into a ring with matching threaded holes.
Classic lanyard consists of details:
- strong cast coupling of an elliptical or elongated rectangular shape;
- two holes with the opposite direction of thread rotation, located in the center of the coupling fillets and strictly along the axis of the entire product;
- two screws with fasteners (rings/hooks/loops/forks) at the ends, made in the form of rods, providing the necessary tension (cables/ropes/chains) when they rotate in opposite directions.
Hook-ring lanyard
The ends of the screws are produced both with an eye (eye) and with a hook - fork. It is to them that the cable (chain) should be attached. Tension adjustment occurs when the ring rotates, when the screws should gradually move towards the center. Ratchets are used in situations such as pulling rope between poles where a high pulling force is needed.
Turnbuckles vary in weight, starting from a few grams, when a tension force of several kilograms is needed, for example, when installing curtain strings, reaching tens of tons when the devices are included in engineering projects for the construction of buildings and bridges.
Rope tension
GOSTs and other normative standardization documents
The regulations for the manufacture of cable tensioners in the post-Soviet space adopted the following regulations:
- GOST 9690-71;
- OST 5.2314-79.
Views and guests
International Standards production regulation, specifications turnbuckles are based on DIN 1478, DIN 1480.
Get all the important information just by carefully looking at the handle with the accepted marking, at the hooks indicating the caliber (diameter) of the cable / chain that is allowed for use.
Typical Dimensions
Principle of operation and tension adjustment
The correct functioning of the tensioners ensures that the two screws rotate in opposite directions at the same time, which is available due to the application of opposite threads. This process ends when a sufficient tension force is reached in the cable / rope / chain, which allows you to secure at a certain moment a specific object - cargo, property, pole, mast, etc.
Riggers, builders, interior designers, antenna installers and even piano tuners, precisely because of their maximum skills in sensing the moment of sufficient fastening tension, can be considered professionals in their field.
Fastening structures
Simple tension adjustment makes it easy to loosen, and fastener installation technology provides a comfortable dismantling option, should the need arise. The simplicity of the designs of such fasteners can also be considered a valuable advantage, which always eliminates additional risks of its destruction during operation.
Masters have the possibility of preliminary preparation / assembly a large number elements for fasteners, if such preparatory work give additional advantages in the speed of their installation already directly on the object, it is also possible to use non-separable ratchets.
Cargo attachments reach a weight of 25 kg, withstanding a load guaranteed by certificates of up to 90 tons. This means that with the help of several fasteners it is possible to fix almost any object, correctly calculating the load.
Tension system device
Types of tensioners for cables and chains
All tensioners can be divided according to several important features, one of which is the material for their manufacture.
Principles of classification and types of devices
Due to the use of this fastener in conditions of constant adverse effects of atmospheric phenomena, lanyards are mainly used:
- from stainless steel alloys;
- made of galvanized metal.
For the manufacture of tensioners, only the highest quality steel is suitable, from which products are produced by forging, which are subjected to the passivation process in the next technological step.
Passivation is the application of a protective layer by exclusively hot galvanizing, which provides the necessary anti-corrosion properties to fasteners used for continuous long-term operation in humid environments without loss of quality characteristics.
plug-plug type
In addition, it is important to break down the types of fasteners at the ends of the screws, among which the most commonly used products are marked:
- C+C (hook/hook);
- C+O (hook/ring);
- O+O (ring/ring).
Hook-ring type
Such fasteners can be open and closed. The second type is more common in more modern models used to secure fiber optic cables.
The choice of fasteners for specific tasks
Experts recommend using turnbuckles of a specific marking in the optimal configuration for each task. So, for example, “C + C” fasteners are most often used where it is necessary to lengthen the cable / chain, change their tension. Most often, these are masts and antennas.
The C+O system serves a similar purpose. And lanyards marked "O + O" will come in handy where ropes / chains / cables with hooks at the ends are used. Chain ratchets allow you to pull together loads that are quite distant from each other. The features of such fasteners are described in more detail in the next paragraph.
Application in cabling
Chain ratchet - design and application
The lanyard shown as an example in the photo is called a chain ratchet. It is highly durable and reliable.
Applications and main purpose
Such a tensioner is intended primarily for fastening systems on trawls, as well as for rigging when transporting goods in the logging industry. A chain lanyard is necessary for high-quality tension of chains used in tying bulky goods.
In most rigging instructions, a chain tie is recommended for use when transporting especially heavy loads (large-diameter pipes, logs), as well as special equipment (turbine parts, large-sized oversized machines, for example, equipment for running in wheel sets of railway trains, or for turning large-sized parts ) on trawls.
Such rigging devices are distinguished by their ergonomics - their device allows the operation of tension with one hand in order to calmly hold the chain in the process of its execution with the other.
Ratchet chain
Features of the design and operation of chain ratchet
Ratchet chains using a ratchet mechanism are more often made with hooks, but models with eyelets at the ends are also used. The standard version of the chain turnbuckle uses hooks that are suitable only for chains of a certain caliber (diameter).
The device was created under the parameters of exposure to an exclusively axial linear force, therefore, lateral loads are strictly contraindicated. They are never used to lift loads. The standard chain tie kit includes:
- chain with hooks at the ends (3-5 m);
- chain lanyard.
Screen fixing
Each ratchet, according to the results of laboratory tests, is necessarily certified, as it is a source of a potential threat to injury to workers, damage to property, and the creation of emergency situations. When choosing this type of attachment, always take into account the load power in relation to the gauge of the chain used!
Areas of application for tensioners
Where can you see working lanyards? The answer is simple - almost everywhere where you need to fix objects of various sizes with symmetrical tension from opposite sides. Devices are not suitable for lifting / transshipment of goods, but are used only for fixing during transportation by any means of transport, as well as at stationary objects - for guaranteed stability. It can be:
- TV / radio towers;
- lightning rods;
- satellite dishes;
- water towers;
- poles;
- fasteners for shelving in logistics centers;
- tower structures;
- auxiliary construction equipment;
- industrial/civil buildings/other structures;
- objects that require reconstruction or maintenance of a safe condition that protects against further damage;
- flagpoles;
- sports equipment;
- heavy fences;
- monuments;
- attractions, high-rise parks;
- temporary/transport facilities (tents, tents).
Antenna Mast Mount
The areas of application are constantly expanding. But just a century ago, turnbuckles were used exclusively by sailors! This is true for both domestic and industrial applications of fasteners. You can observe small products in the design of window openings with cornices / curtains / blinds. And you can't help but notice the giant lanyards in the structures of modern bridges and buildings with a special architecture that involves additional supports and fixation.
Rope tension instructions
Before pulling the cable between the posts, you should study all the rules for the safe use of turnbuckles - both for the installation process and for subsequent operation. To do this, you must first choose the right tensioner for the task. Use the table below to make the right choice.
Main stages and rules of work
Having chosen the necessary lanyard, you should act in compliance with the following technology:
- Wipe the tensioner with gasoline.
- Polish it with a felt wheel.
- Apply grease (graphite/molybdenum bisulfate).
- Run empty.
- Turn a couple of times during installation.
- When installing with sea water ingress, rinse with fresh water (to prevent parts from sticking together).
- Install the cable tensioner by turning the screws in opposite directions until the effective tension is reached, when the load or structure is effectively secured.
- If the cable is overstretched, loosen the tension by gently turning the screws in the opposite direction to the original.
- If necessary, replace bent parts.
- Make sure there is no load other than axial.
- Periodically check the quality of the cable tension, adjusting it if necessary by the same method that was used during the initial installation.
Rope tension
For such devices, the most important correct installation, which allows during the further operation of the tensioners to give them a minimum time for condition monitoring, scheduled maintenance, while maintaining the guaranteed quality characteristics specified in the certification documents. Following all the points of the above instructions, you can always qualitatively, reliably pull the cable without outside help.
Having studied the information about lanyards, and having figured out what it is, what it is used for and how it is divided into types, you can independently choose a fastening device for specific purposes without risking the reliability of the structure being fixed.
For beginners who want to improve their professional level, as well as for those who use fasteners on their own in everyday life, it is useful to watch a video with details of the correct installation technology for various types of lanyards.
Video: What is a lanyard and how it works
A carbine is a well-known name, like an earring, but most of us hear the names of a lanyard and a thimble for the first time. Not everyone knows such specific objects, so information about them will not hurt anyone. You have to meet with them when it becomes necessary to hang or fix something.
If you have a professional rigging system available, then many tasks can be solved much faster than with conventional improvised means. Any hardware store offers various cable clamps for such work, which will allow you to securely fasten the whip when forming a loop at the end of the cable using a lanyard, pull the cable with the necessary force.
Lanyard
This is a commonly used cable tensioner, or screw tensioner. It usually consists of three parts: a pair of screws and a housing. By rotating the body of the lanyard, tension occurs. Depending on the need to tighten the cable or relax, the lanyard is equipped with right and left threads, where, when the body rotates, the screws approach each other, or unscrew, moving away from each other. At the end of the screws there can be locking forks, hooks, rings. Steel, as a rule, for the manufacture of lanyards, high-alloy, high-quality steel is used, with a protective coating of nickel or zinc. This prevents the device from rusting.
Yachtsmen and installers know best about such a device. In everyday life, there are many options for using this device. For example, when mounting the antenna on the roof, when attaching lamps and installing fences.
Earring
When working with ropes and cables, earrings are often used. This is a U-shaped connecting element with a screw-in stopper (finger). Earrings are used to quickly connect several strands of cables, for fastening to brackets and lugs. Attachments are available in various sizes to suit different cable thicknesses and loads. To attach the cable to the hook, you need to make a loop at the end of it, and for this there are several types of easy-to-assemble clamps. The diameter of the cable for which the clamp is designed is indicated on the body.
Koush
To strengthen the loop, for a high cable load, a thimble is inserted inside the loop. All deformation during tension does not go to the cable, but to a drop-shaped loop stamped from metal, so that the cable does not bend and wear out less. The earcups have different sizes. Depending on the thickness of the cable, the right one is selected. In addition to thimbles for ropes, thimbles for terminating ropes with a plastic base are produced.
Carbine
A useful addition to the set of above devices. Carabiners are used for quick coupling and disengagement of connections.
When carrying out rigging, installation and construction works often there is a need to fix and lengthen the used steel ropes, as well as to create loops and eyes at their ends. For these purposes, rope clamps (rope clamps) are used.
A rope clamp is a device used to fix and secure a steel rope.
This type of rigging is not intended for work related to lifting, moving, holding on weight and lowering loads. Its main purpose is to ensure a strong tension of ropes and cables during the installation of structures and fixing objects in a fixed position, for example, on a vehicle platform during transportation.
Clamps (rope clamps) are used in conjunction with a pear-shaped asymmetrical thimble to fix the rope in the device for joining the rope.
The size of the steel cable clamp is determined by the diameter of the cable used.
Types of rope clamps
There are clamps for ropes and cables of the following types:
1) U-clamp
The clamp is a threaded u-bolt. The threaded ends of the bolt are inserted into the clamping element. When tightening the nuts of the steel clamp, the element presses the cable against the bolt.
2) Flat cable clamp
Made from carbon steel. Consists of clamping element, clamping plate, screws and nuts with metric thread. Depending on the number of screws in the design, the flat cable clamp is single (simplex), double (duplex) and triple (triplex). Tightening the nuts clamps the cable between the plates.
3) Tubular clamp
Aluminum clamps-sleeves are used for ordinary cables, copper - for acid-resistant, stainless steel clamps are used for work in aggressive environments. The tubular clamp is an aluminum flattened hollow cylinder.
Recommended for connecting cables to each other, as well as for making loops at the ends of the cable. Tubular clamps for steel ropes are compressed using a press or hand pliers. They are one-time non-removable elements.
Depending on the design and installation method, metal cable clamps are divided into:
- wedge
- bolted
- screw
- wedged
- pressed
- canine
All rope clamps are manufactured in accordance with DIN and GOST. In lifting devices, for the purpose of connecting the ends of the ropes, it is recommended to use DIN 1142 arc-shaped clamps. The DIN 741 cable clamp has a lower strength compared to DIN 1142, therefore it is recommended for use in work not related to moving and lifting loads.
Types of materials and coatings
Most often, cable clamps are used in work with large weights and heavy loads, therefore, strict quality control standards are applied during their production. Clamps for steel cables are made exclusively from high quality and durable materials: steel, copper, aluminum, stainless steel.
In addition, rope clamps can be galvanized. Galvanized clamps have additional protection against corrosion. When working in adverse weather conditions and aggressive environments, stainless steel cable clamps are used.
Installation of clamps on the ropes and fastening
When using arcuate clamps, it is recommended to install at least three clamps on one rope. If the load is higher than these types of clamps can withstand, then you need to use a different type of this latch, and not increase their number.
The rope clamp is mounted on the steel cable so that the clamp web is always on the load-bearing side of the rope. A U-shaped clamp bolt is located on the tail of the rope or cable. The long part of the cable is bent so that the minimum required number of clamps can be positioned to create a strong loop. The distance between the clamps and the length of the free end of the rope from the last clamp must be at least 6 rope diameters.
Operating rules
Before starting work, it is necessary to check the strength of the rope fastening with clamps. After the first load has been applied to the cable, the tightening torque must be checked again and adjusted if necessary. Products need to be checked and tested regularly. This is necessary due to the fact that during operation the products are subject to wear and overload, which will lead to deformations and changes in the structure of the material. Rope end clamps should be inspected at least once every six months, and even more frequently if products are used under severe working conditions.
It is not allowed to bend or correct the shape of the clamp, as this will lead to a deterioration in the quality of the product and a decrease in its ultimate strength.
The tightness of the clamps on the cable can be adversely affected by the following factors:
- the nut sits tightly on the thread, but not tightly in relation to the jumper;
- the thread is clogged with dirt, oil, corrosion products that prevent the proper tightening of the nut.
Before choosing a certain product, you need to make sure of its quality. To do this, pay attention to the following points:
- clamps must be legibly marked;
- there should be no visible burrs, cracks, grooves and other manufacturing defects on the surface;
- clamps must be selected according to the characteristics of the ropes used;
- the type of clamp material/coating must match external factors and the conditions under which the work is carried out.
All these types of rope clamps are designed and manufactured to order by GPO-Snab. You can pick up and order them in our catalog of rigging products.
