Installation of the cable line. Methods for laying cable lines

2024 Author: Howard Calhoun | [email protected]. Last modified: 2023-12-17 10:16

Organization of power supply networks involves the implementation of a wide range of activities, in which the laying of the cable plays an important role. A variety of technologies and methods are involved in the work on the electrical infrastructure. Workers are required not only to physically install reference points with lines, but also to select the optimal installation configurations, which will increase the operational life of the facility. To date, the laying of cable lines is implemented in many ways - from the arrangement of underground channels to fixing the circuit in special structures. Each installation option requires compliance with specific standards and technical regulations.

General cable line installation technology

Installation operations with power cables are mainly limited to the physical fastening and organization of systems that hold the lines in position. Auxiliary technical measures are also common, including connection and termination. Connecting wires to electrical equipment is carried out using cable sleeves, terminations and clamps. The main thing in this part of the work is to correctly compare the size of the fixing fittings and the cable itself. The quality of the assembly operations is alsodepends on how accurately the initial preparation of the material for the same compounds was carried out. Cutting and stripping the ends of the wire is not complete without special tools, including strippers, wire cutters, clamping pliers, etc. In addition, the installation of a cable line may involve the use of protective electrochemical compounds. These may be sealing preparations that provide insulating barriers. The application of such materials in the process of working with wiring requires care and adherence to the installation technology of a particular cable.

Laying the cable in the trench

This is one of the most common cable installation methods and is appropriate for non-paved areas where there is also a minimal risk of physical damage to the line. Laying begins with the formation of a trench into which the wire will be immersed. In order for underground cable structures to have a solid foundation in the lower part and not freeze, the technology instructs the performers to create a pillow in the form of a small mound. It may include sand, gravel or crushed stone - the height of the coating reaches an average of 10 cm.

The prepared cable is immersed in a trench and then insulated with special windings. If necessary, separate sections are connected with the expectation of strengthening the convergence points with auxiliary reinforcement. If conditions allow, then it is advisable to make the connection of wires and cables during underground laying in advance. The same applies to insulation work, although the transportation process also does not always make it possible totechnical preparation of the cable line. The advantages of this method include a minimum of financial costs and the possibility of the most beneficial use of the wire section. The disadvantages of underground laying technology include the lack of access to the line: for inspection and diagnostics, you will have to excavate the trench.

Rolling out cables in the ground

The technique of laying the cable in a trench involves rolling. Actually, this operation in one form or another is also required for other mounting technologies, but in this case, approaches to its implementation are most pronounced. There are two methods of rolling. In the first case, cable lines are laid using a special conveyor that grabs the end of the wire and, as it moves along the trench, lays it to the very bottom. Workers in the process of performing this operation monitor the correctness of rolling and the accuracy of the position of the wire at the bottom of the trench.

The second method of rolling does not involve the use of moving equipment. The drum, on which the cable was pre-wound, is fixed in one place so that the wire can be untwisted. For ease of rolling, special rollers with clamps are used. They are fixed at the end of the cable and its free laid part with one or another step, the distance of which depends on the weight of the wire. If in the future it is planned to install a cable line in the form of a connection with other segments, then this option may not be suitable due to the risk of breaking the line at the attachment point. In such situations it is betteruse the same transporter.

Laying in block constructions

Block structures are understood as different structures. A classic example is an asbestos-concrete pipe into which a cable is inserted, the diameter of which is 1.5 times smaller than the reinforcing sheath. Another type of block is a honeycomb panel, into which lines of wires are also introduced. This option is suitable in cases where you need to lay several circuits in a small area. Such blocks do not provide continuous insulation, but only separate the wires at certain laying points. Block technology for mounting cable lines is highly reliable, which is achieved due to effective protection against mechanical damage.

However, the resistance of the line will depend on the type of protective structure used. Obviously, the most reliable solution will be the use of tubular channels, but it is also the most costly and difficult to implement. The same rolling with such a scheme can only be performed manually without the use of a conveyor. On the other hand, in some installation conditions, the use of blocks becomes the only acceptable way to set up a line. In particular, pipes for laying cables are used at the intersection of the contour with roads and railways. Also, you can’t do without additional strengthening of the wire if you plan to lay it in soils with an aggressive composition in terms of chemical attack.

Laying the cable in the channel structure

It has already been said that the mainThe disadvantage of laying the line in a trench underground is the lack of direct access to the cable without excavation. Combine the advantages of laying in a trench and block technology allows installation in a channel structure. With such a circuit design, maintenance of cable lines is allowed without excavation, that is, it remains possible to access the line to perform repair and diagnostic measures. The channel itself is in some way a box, the walls of which are formed by concrete slabs or bricks. It turns out a closed structure, which contains the cable.

The contour is also in the ground, but closer to the surface than in the case of trench laying. Moreover, this scheme is used at enterprises directly on the premises, so the upper part of the box is literally on the surface. But if the installation is carried out outside the production premises, then the performers immerse the structure in the ground. But this does not mean that large-scale land works in the form of excavation will be required to access communications. The internal installation of the cable line in the channel is carried out using special suspensions and clamps. In some cases, traditional laying on the bottom with the use of substrates is carried out.

Laying in sewers and tunnels

Tunnel structures are usually included in the infrastructure of industrial and manufacturing facilities. These are small corridor-type rooms in which communications are laid. In terms of reliability anddurability, this installation option can be considered the best. Fastening of wires is carried out by means of special couplings. Initially, the tunneling project provides for the possibility of integrating communication lines into special niches. Collector rooms are even more technologically advanced in terms of maintenance. The features of such objects include the possibility of laying a large number of wires - as a rule, up to 20. Each line is also supplied with insulating windings, but in this case there is no need for armored protection. At the same time, the construction of cable lines is allowed only in those collectors and tunnels where water collectors and storm sewer systems are provided. Depending on the operating conditions of the wiring, it may also be necessary to install ventilation systems, including installations of artificial and natural circulation.

Special attention should be paid to the technique of rolling the cable in the tunnel. The use of conveyors, as well as massive drums, is impossible in this case. Unwinding is carried out manually or using a winch mechanism. If a thick cable or several wires are being serviced at the same time, then roller systems are also involved. The undeniable advantages of this type of cable laying include a high degree of line protection and direct access for maintenance. However, such laying conditions are rare and are laid down as part of the technological infrastructure in industrial projects.

Laying in galleries

In this case, we are talking about ground structures that canset up outside the technological premises. Galleries are called flyovers, which, like a tunnel, can pass through the most critical sections of the laying. If overhead communication lines are laid along poles on weight, then in the case of galleries, installation is carried out in closed structures. However, there are different versions of flyovers. Sometimes, in order to save money, designers develop structures without side walls. Also, objects of this type differ in the possibilities of passing inside. There are structures in the niches of which even transportation can be carried out, and there are also structures with limited access only for technical work on the repair, diagnostics and maintenance of the line itself.

This option, despite its attractiveness, is not used so often due to high financial costs. Nevertheless, it is the only possible one when it comes to laying within enterprises, whose underground channels are already saturated with communications. As for the protection of lines, ground structures provide the necessary level of security. On difficult sections of the route, asbestos-concrete pipes for laying cables can also be used, which protect the circuits from destructive mechanical and atmospheric influences.

Cable suspension

This option involves the implementation of the classical scheme for hanging installation of lines. This method is distinguished by ease of execution, economic availability and the possibility of convenient installation and repair.operations. However, not all cable communications, in principle, can be carried out by this method: first of all, this applies to cases where it is necessary to install a cable line supplemented with thick layers of insulation. Do not forget that overhead wiring is operated in open conditions with direct exposure to ultraviolet rays, high and low temperatures, precipitation, etc. Accordingly, some types of cables require effective insulation, which makes the line heavier, causing problems during installation.

It cannot be said that overhead wiring is significantly superior to underground installation, but in situations where the arrangement of the same trenches is not possible, this method is quite worthy of consideration. Direct installation is carried out on supports and poles of high-voltage lines. During installation, electrical cables are insulated in accordance with the brand of wire. When choosing a means of protection, specialists take into account such characteristics as dynamic resistance, strength, frost resistance, ability to withstand and not deform before short-term loads, etc. Further, during maintenance at certain intervals, the insulating sheath can be replaced, as well as the cable.

What is a heating cable for?

As part of sets of communication lines, there are often technological wires and materials that are not the main conductors, but perform important auxiliary tasks. These include heatingthe wire. Its function is to ensure the optimal temperature regime in which power communications should be operated. Thus, cable lines are protected from freezing, in which the wires lose their operational properties. An electric charge is supplied to the heating circuit, which, thanks to a special alloy of the inner core, is converted into thermal energy that heats nearby wires.

Heating conductors are rarely found directly in cable wiring. Usually, the function of keeping warm is performed by the main insulation. Most often, heating lines are used as an addition to process equipment. Tanks, pipelines, separate parts of transformers and industrial equipment are insulated using this technique. The features that the heating cable has include a protective sheath made of polymeric materials. Also, depending on the brand, manufacturers use different means of electrical shielding. For example, solid aluminum or copper wire mesh can be used in this capacity. The main sheath is made of polyvinyl chloride, which protects the conductors from mechanical damage. In addition to providing heat, anodized conductors can also serve as an effective electrochemical corrosion protection agent. This kind of protection is required for metal fittings, which are used for fastening and tying communications.

Conclusion

Installation operations in working with cablespower transmission is preceded by the development of the project. The compiler of the technical plan for laying communications takes into account many operating factors that give him reason to make a choice in favor of one or another method of laying. For example, overhead communication lines are organized in cases where there is no possibility of using more reliable ground-based installation schemes. Underground methods of conducting communications justify themselves in many respects, but due to the lack of the possibility of direct access to the line, they are also often abandoned. If we are talking about organizing a network adjacent to industrial enterprises, then it is more likely that part of the circuit can be laid in a technological tunnel or collector room. In addition to the external conditions of laying, the operational requirements for the cable itself are also taken into account. Only a comprehensive analysis of the conditions for the implementation of the design task can give the correct answer to questions about choosing the optimal cable line installation scheme.