Lanyard is a useful device with an unusual name for working with heavy objects. Technology for laying cables on a cable How to stretch a metal cable between poles
There are situations during electrification when it is necessary to supply electricity to a separate room. At the same time, it is not possible to lay the cable in a trench due to the complexity of the terrain or architecture. Therefore, along with such types of external laying as trays, cable ducts, pipes, corrugations, wall mounting, there is such a type of laying as cable wiring. In this article we will look at the technology of installing a cable on a cable with your own hands.
Application area
According to this method, it is applicable for networks up to 1000 volts. Most often, cable wiring is used in places where organizing an overhead line does not make sense, and it is enough to throw a cable attached to the cable, and this will be enough to electrify the facility.
In this way, lighting networks and electrical wiring for sockets are carried out in warehouses, power cables V production workshops, as well as between two separate buildings.
For home handyman this method wiring has a certain interest. This is because with the help of simple technology it is possible to electrify outbuildings in the country. Thanks to cable wiring, it is possible to conduct light from the house to a bathhouse, garage, shed, gazebo and others spaced some distance apart. personal plot buildings and lighting devices.
Preparatory work
First you need to decide on the wire and its cross-section. We talked about this in the corresponding article. After this, you need to measure the length, taking into account the entire route of wiring from the machine to the distribution panel. When choosing a cable and suspension elements, you need to take into account the weight of the wire in a given section, with a threefold safety margin. Since in difficult weather conditions the load on suspended structure increases, can cause a break and blackout. Mostly galvanized steel cable with a diameter of 4.6 to 6.8 mm is used. In cases where the length of the suspension is short and the weight is such that it can be neglected, instead cable wiring you can use string wire (galvanized steel wire or varnished hot-rolled wire from 5 to 10 mm is pulled).
Installation technology
First you need to secure the anchor and the fastening elements of the cable wiring to the selected area. For the most part, these are steel plates pulled together on both sides of the wall with studs and rings welded to them for hanging the cable. The tension of the fastenings is done to strengthen and avoid their falling out, distributing the weight of the load evenly along the wall, and not at the fastening points.
The height of the suspension should not be lower than 2.75 meters above the pedestrian area, and not less than 6 meters above the vehicle passage. All standards for overhead electrical wiring, including the distance between supports, are indicated in the diagram:
After installing the strings, they begin tying the cable with a bandage. To hang cable wiring on the street, you can use plastic clamps, galvanized iron strips, and galvanized binding wire. The distance between the bandage is 50-80 cm.
When using a binding wire, it is necessary to prevent the core from cutting into the insulation; for this, a gasket is made between the bandage and the wire from insulating material. The winding area of the bandage should be distributed as much as possible by laying 7-10 turns of the bandage. Using plastic clamps, check their operational data. Otherwise, in frosty winters or very hot summers, you will find scattered clamps.
At external laying cable along the cable, it is also necessary to protect the line from the influence of the environment on the insulation, so it is recommended to stretch it in a corrugation, as shown in the photo below. This will then reduce the cost of operation and restoration of cable wiring.
If the span is short or there is no possibility of attaching the cable to the cable at the installation site, it is possible to assemble the suspension on the ground. The already prepared structure can be stretched and attached.
By following our instructions, you can independently conduct electrical wiring to separate buildings in the country. We also recommend watching a useful video that shows how to make a loop on a cable with your own hands:
Preparing the cable
That's all I wanted to tell you about how to install cable wiring with your own hands. As you can see, laying a cable along a cable is a rather labor-intensive task, but it is still within the power of a home handyman!
When carrying out rigging, installation and construction work often there is a need to fix and lengthen the used steel ropes, as well as creating loops and eyes at their ends. For these purposes, rope clamps (cable 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 and lowering loads. Its main purpose is to ensure strong tension of ropes and cables during the installation of structures and securing objects in a stationary position, for example, on a platform vehicle during transportation.
Clips (rope clamps) are used in conjunction with a pear-shaped asymmetric thimble to secure the rope in a device for splicing the rope.
Clamp size for steel cable determined by the diameter of the rope 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 the steel clamp nuts are tightened, the element presses the cable against the bolt.
2) Flat cable clamp
Manufactured from carbon steel. Consists of a clamping element, a clamping plate, screws and nuts with metric thread. Depending on the number of screws in the design, the flat cable clamp can be single (simplex), double (duplex) and triple (triplex). Tightening the nuts clamps the cable between the plates.
3) Tubular clamp
Aluminum bushing clamps are used for ordinary cables, copper - for acid-resistant ones, for work in aggressive environments, clamps made of of stainless steel. The tube 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, clamps for metal cables are divided into:
- wedge
- bolted
- screw
- jammed
- pressable
- canine
All rope clamps are manufactured in accordance with DIN and GOST. IN lifting devices for the purpose of connecting the ends of ropes, it is recommended to use arc-shaped clamps DIN 1142. The cable clamp DIN 741 compared to DIN 1142 has less strength, 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, so their production is subject to strict product quality control standards. 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 rope clamps and fastening
When using arc 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 another type of this clamp, and not increase their number.
The rope clamp is installed on the steel cable so that the jumper of the clamp is always on the load-bearing side of the rope. There is a U-shaped clamp bolt at the tail end of the rope or cable. The long part of the cable is bent so that the minimum required number of clips 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, you need to check the strength of the rope clamps. After the first application of load on the cable, the tightening torque must be checked again and adjusted if necessary. It is necessary that products are regularly inspected and tested. 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 often if the products are used in harsh working conditions.
It is not allowed to bend or adjust the shape of the clamp, as this will deteriorate the quality of the product and reduce its ultimate strength.
The following factors can negatively affect the tightness of the clamps on the cable:
- the nut sits tightly on the thread, but not tightly in relation to the jumper;
- the thread is clogged with dirt, oil, and corrosion products, preventing the necessary tightening of the nut.
Before choosing a specific product, you need to make sure of its quality. To do this, you should pay attention to the following points:
- the clamps must be legibly marked;
- there should be no visible burrs, cracks, grooves or other manufacturing defects on the surface;
- clamps must be selected in accordance with the characteristics of the cables used;
- The type of material/covering of the clamp must match external factors and the conditions in which the work is carried out.
All of these types of rope clamps are designed and manufactured to order by GPO-Snab. You can select and order them in our catalog of rigging products.
When using metal ropes, it may be necessary to fasten them together or form loops at their ends. A steel cable clamp will help you cope with this task effectively. We will describe below what modifications exist and how to use them.
Purpose and design specifics
These devices are made of durable materials - it is thanks to metal that reliable fastening, withstanding increased loads. Structurally, the clamp consists of an arc and nuts.
It is advisable to use several clamps - professionals advise using at least three. However, if the load is excessively high, then it is better to choose other methods of fixation and refuse to install a large number of clamps.
High-strength steel is additionally treated with galvanization. Such protective layer protects elements from corrosion and also minimizes the impact of other external factors.
To prevent disengagement and breakage, you should learn how to use the cable clamp correctly. There is nothing complicated about this - just put the ends under the arc and tighten it with nuts. They twist in different directions, and the rope remains in the spaces between them.
The nuts must be tightened until the cable is completely tightened. If a loop is being created, the cut end should be on top, above the whole piece, but directly below the arc. Clamping element– nuts – will be at the bottom.
Classification of devices
You need to select clamps taking into account the specific conditions of their use, the characteristics of the cable used and the planned load. In terms of size, you can choose a wide variety of modifications - they can be small 3-5 mm in diameter, but there are also larger ones up to 40 mm.
Most often used in everyday life conventional designs, which are made from second class steel after galvanization. They have a loop at the base that is clamped with bolts. However, professionals demand reinforced modifications with a more durable shutter. Therefore, they are oriented towards increased load levels.
Steel or copper is used for manufacturing, although in some cases it is permissible to use only an aluminum cable clamp. But galvanized steel will be a more expensive option, but will allow fasteners to be used in harsh climatic zones.
The design also varies - they can be single or double, have a flat or arched design. Flat models have two galvanized steel plates with a diameter of 2-40 mm.
Fastening is done using bolts and nuts. Their use is effective when splicing cables and carrying out other similar manipulations. To connect, you need to install more than two devices.
Double cable clamps are distinguished by the presence of two fixing bolts, while single clamps have only one bolt-nut pair. Their operating principle is almost identical.
The arched design has cylindrical shape with an arched convexity. There are bolts at the ends that provide fixation. Most often they are used in connecting operations, but fastening a loop is also acceptable. This industrial version fasteners that can withstand a load of at least 97 kg.
The crimp clamp is made of aluminum alloy. It looks like an oval piece of pipe with a slight flatness on both sides. The cable is inserted into this section, and the structure is flattened in two ways:
- impact with a hammer;
- manually by pressing.
Specific types of clamps
Since fastening units in construction experience dynamic loads, and loads often rise to a height, spring mechanisms are used here.
Thanks to them, not only the usual fastening of cables is carried out, but also the fixation of objects. Structurally, they have levers with moving brackets. As a result, the object can be fixed on the cable, regardless of its thickness.
Wedge connections are indispensable for working with copper and aluminum wires with a cross-section of 35-100 square meters. mm. They are made of cast iron steel with a wear-resistant wedge made of bronze or aluminum alloys.
For greater clamping reliability aluminum wires For large sections, special gaskets made of the same material are used. The fastening will be strong, but the bolts should be tightened every 7-10 days.
Selection and use
The photo of cable clamps shows various modifications that can be used for a specific installation purpose. It is important to check:
- presence of markings;
- absence of defects and defects;
- compliance of the clamp with the parameters of the rope.
When fixing the rope, the jumper should be on the side of the rope where the main load is present. Before use, check the tightness of the fastening. It is not allowed to influence the mechanism by welding.
The use of clamps allows for reliable and durable fastening when connecting cables or forming a loop. You can make them yourself, but purchasing factory-made products will ensure the durability of the fasteners.
Photo of cable clamps
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 elevator facilities, when carrying out various installation work, as well as in everyday life.
Types of clamps
To ensure durability and reliability, everything structural elements Clamps are made of stainless steel, and for light operating loads - also of copper, brass or aluminum.
The most popular are:
Features of using different types of cable clamps
Main technical parameters of the products under consideration are the maximum cable diameter and the guaranteed clamping force. The dimensions of the clamp are also important, since it is recommended, regardless of the 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 this clamp allows for the installation of a locking bar, which provides more reliable clamping of the cable to the bracket. The clamping block must be made by stamping from steel grade no lower than St.3kp in accordance with GOST 380-94 (only for small clamping forces cast blocks made of steel 25L in accordance with GOST 977-75 are allowed). It is not allowed to use cable clamps whose parts do not have a protective anti-corrosion zinc coating.
IN fasteners For flat clamps, threads in accordance with GOST 24705-81 must be used. The material of the linings is steel St. 3, the plates should be used for fastening cables with a diameter of 4.6...30 mm.
If several clamps are used in series, the distance between them should not be less than six cable diameters.
In Duplex type double clamps the shear force is absorbed exclusively bolted connection, therefore the choice of fastener diameter is determined by the diameter of the cable. The following ratios are recommended:
- For cables with a diameter of 2 mm and 3 mm - M4 fasteners;
- For cables with a diameter of 4 mm and 5 mm - M5 fasteners;
- For a cable with a diameter of 6 mm - M6 fasteners;
- For a cable with a diameter of 8 mm - M8 fasteners;
- 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 fastener are reduced, since the axes of force during operation of such a clamp coincide, and, therefore, shear stresses do not arise. The operational parameters of wedge-type clamps are regulated by DIN 15315. For screw clamping of a cable or rope to the supporting surface of the wedge, high-strength fasteners are used (strength class not lower than 5.6), with a protective anti-friction coating. The connection needs to be tightened periodically.
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 this clamp allows it to be used in cramped 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 type clamps - 4…14;
- For Duplex type clamps – 7…24;
- For clamps according to DIN 741 - 4…160;
- For wedge clamps – 200…250;
- For barrel type clamps - 3...40 (made of aluminum), and 60...160 (made of stainless steel).
In everyday life (for example, for car enthusiasts), there is often a need to make a cable clamp with your own hands. To form a reliable loop, it is advisable to use a regular aluminum (not duralumin!) tube, into which the cable should fit freely required diameter. 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 can fit in freely, and from different ends. All other actions are performed in the same way. It should be noted that load bearing capacity such a cable clamp will be determined by the bending strength of the pipe material, so the permissible force homemade device the clamp will be noticeably lower than that manufactured by a specialized enterprise.
