What is the cable structure used for? Laying cables along the structures of buildings and structures

Installation of cable structures

General requirements. 4
The order of work. 5
The need for machines and mechanisms, technological equipment and materials. 7
Team composition by profession... 7
Solutions for occupational safety, industrial and fire safety. 8
Operational quality control scheme. 13
Schemes of work execution. 15
Familiarization sheet. 17

1. General requirements

The technological map has been developed for the implementation of a set of works on the installation of cable structures (racks, shelves, boxes, trays, pipes) for electrical installation work during the construction of the facility

The technological map has been developed in accordance with the requirements of the following regulatory and technical documentation:

SNiP 12-03-2001. Occupational safety in construction. Part 1 General requirements;
SNiP 12-04-2002. Occupational safety in construction. Part 2 Construction production;
SP 12-136-2002. Occupational safety in construction. Solutions for labor protection and industrial safety in construction management projects and work execution projects;
SP 126.13330.2012 Geodetic work in construction. Updated version of SNiP 3.01.03-84;
SP 45.13330.2012 Earthworks, bases and foundations. Updated version of SNiP 3.02.01-87;
SP 48.13330.2011 Organization of construction. Updated edition
SNiP 12-01-2004;
OR-91.200.00-KTN-108-16 “Procedure for implementation construction control the customer when performing construction and installation work at the facilities of Transneft system organizations.”
OR-91.040.00-KTN-109-16 “Requirements for quality services of construction contractors at the facilities of Transneft system organizations.”
OR-91.010.30-KTN-111-12 “Procedure for developing projects for the construction, technical re-equipment and reconstruction of main oil pipelines and oil product pipelines.”
RD-93.010.00-KTN-011-15 Main pipeline transport oil and petroleum products. Construction and installation work performed on the linear part of main pipelines
OR-91.200.00-KTN-201-14 Main pipeline transport of oil and petroleum products. The procedure for organizing and implementing construction control over compliance with design decisions and the quality of construction of underwater crossings of MN and MNPP
RD-35.240.00-KTN-178-16 Requirements for equipment installation automated systems process control

2. Work procedure

General technical requirements.

Before installation begins, it is necessary to carry out a set of organizational and technical measures and preparatory work:

1) organizing a team of workers;

2) appointment of a person responsible for the quality and safety of work (foreman, foreman);

3) provision of workers necessary equipment, tools, equipment, devices, special clothing and safety footwear in accordance with established standards;

4) providing jobs with first aid medical care, drinking water, fire-fighting equipment;

5) checking and testing of power tools;

6) delivery of equipment to the construction site.

All materials must comply with the requirements of regulatory documents and specifications.

Progress of work during installation of cable structures (racks, shelves, boxes, trays):

1) according to the project, the installation sites of cable structures are marked;

2) drilling is carried out according to the completed markings;

3) installation of racks to the overpass/wall of the room;

4) installation of shelves to cable racks;

5) installation of boxes, trays on shelves with fastening using M8 bolts. Using connecting elements, the boxes are joined, fastened with M6 bolts.

Work on the installation of cable boxes and trays is carried out in accordance with the requirements of SNiP 12-03-2001, SNiP 12-04-2002, PUE ed. 7, SP 76.13330.2016.

Upon completion of installation work, the line of boxes must be straightened with final tightening of all fasteners.

Work progress during installation of cable structures (pipes):

1) The area for laying pipes is marked;

2) a trench is developed for laying pipes (in a marked area, a trench is dug with a depth of 0.9 m and a width of 200 mm to 1000 mm, depending on the number, brand and cross-section of the cable cores in the trench);

3) temporary plugs are removed from the pipes;

4) plastic bushings are inserted into the ends of the pipes so as not to damage the insulation of wires and cables when pulled into protective pipes; lubricants are also used;

Cables are pulled only into fully assembled pipelines. Before cables and wires are pulled into them, the open ends of laid and secured protective pipes are closed with wooden or plastic plugs to prevent dirt from getting into the pipes.

When laying cables in pipes, the pipes used must also be marked inner surface, preventing damage to the wire insulation when they are pulled into the pipe and anti-corrosion coating of the outer surface. Heat-shrinkable insulating tubes are used where wires exit the pipes.

Wires are secured using clamps in branch boxes or at the ends of pipes. Wires and cables in pipes should lie freely, without tension.

The diameter of the pipes is taken in accordance with the instructions in the working drawings.

Monitoring the compliance of the work production process, the quality of work and identifying deviations and inconsistencies with the requirements of the working and regulatory documentation, checking compliance with sequence and composition technological operations during construction, it is carried out at each stage of all work by the Customer's QC body and the Contractor's QC.

It is prohibited to begin a new stage of work without an appropriate examination of the previous one by the Customer's QC and the Contractor's QC.

3. The need for machines and mechanisms, technological equipment and materials

Table3.1

The equipment specified in Table 3.1 and further in the text of this technological map can be replaced by the Contractor with similar equipment available at the time of work based on the required productivity and technical characteristics.

4. Team composition by profession

The composition of the brigade is shown in table 4.1

Table 4.1

5. Solutions for labor protection, industrial and fire safety

When performing work, the following requirements must be observed:

– SNiP 12-03-2001 “Labor safety in construction. Part 1. General requirements";

– SNiP 12-04-2002 “Labor safety in construction. Part 2. Construction production";

– VSN 31-81. Instructions for construction work in security zones main pipelines of the Ministry oil industry;

– SP 12-136-2002. Solutions for labor protection and industrial safety in construction management projects and work execution projects;

– GOST R 12.4.026-2015 System of occupational safety standards. Signal colors, safety signs and signal markings. Purpose and rules of use. General technical requirements and characteristics. Test methods;

– SP 36.13330.2012 Code of rules “Trunk pipelines”

– SP 52.13330.2011 Set of rules “Natural and artificial lighting”

– Safety regulations for the construction of main steel pipelines;

– Rules for labor protection during construction (Order of the Ministry of Labor and Social Protection of the Russian Federation dated June 1, 2015 N 336n);

– Rules for labor protection when working with tools and devices (Order of the Ministry of Labor and Social Protection of the Russian Federation dated August 17, 2015 N 552n);

– RD-13.110.00-KTN-260-14 “Main pipeline transport of oil and petroleum products. Safety rules for the operation of facilities of JSC AK Transneft";

Persons at least 18 years of age who have no medical contraindications for performing this type of work, who have the appropriate qualifications, and are admitted to work are allowed to work. independent work in accordance with the established procedure, having an electrical safety group of at least II. The person responsible for carrying out the work must have an electrical safety group no lower than that of the subordinate operational personnel.

Before starting work, personnel must put on overalls and safety shoes, PPE appropriate for weather conditions, in accordance with approved standards, and a helmet with a chin strap. Overalls, safety shoes and personal protective equipment must be in good working order, fastened with all buttons and fasteners. It is not allowed to perform work in workwear and personal protective equipment contaminated with flammable or toxic materials or with expired wear.

Personnel operating mechanization equipment, equipment, fixtures and hand-held machines must be trained before starting work safe methods and methods of work with their use in accordance with the requirements of the manufacturer’s instructions and labor protection instructions.

While on the work site, all employees are required to comply with the internal labor regulations adopted in this organization.

Admission to the production area of unauthorized persons, as well as workers who are drunk or not engaged in work in this area, is prohibited

Workers engaged in laying cables must be provided with sanitary facilities (dressing rooms, dryers for clothes and shoes, rooms for eating, resting and heating, etc.) in accordance with the relevant building codes and regulations and the collective agreement or tariff agreement.

Preparation for operation of sanitary premises and devices must be completed before the start of work.

At workplaces, workers must be provided with drinking water, the quality of which must meet sanitary requirements.

In sanitary premises there should be a first aid kit with medicines, a stretcher, fixing splints and other means of providing first aid to victims.

Construction machines, mechanisms and equipment must be in good working order and adapted for their safe use as envisaged technical documentation for operation.

It is prohibited to operate construction machines without fencing devices, interlocks, and alarm systems provided for by their design.

Manual electric machines must comply with the requirements of the relevant government standards.

The construction and operation of electrical installations is carried out in accordance with the requirements of the Rules for the Construction of Electrical Installations (PUE), the Safety Rules for the Operation of Consumer Electrical Installations (PTB), and the Rules for the Operation of Consumer Electrical Installations.

Lighting of the work site

At twilight, a temporary lighting mast is installed on the site to illuminate the site of construction and installation work. Electricity is supplied from a mobile diesel or gasoline generator of the Contractor (diesel station). The standard illumination of the construction site is 10 lux

Based on GOST 12.1.046-2014, electric lighting construction sites and areas are divided into work, emergency, evacuation and security. When darkness falls, work areas, workplaces, driveways and passages to them must be illuminated: at least 10 lux when performing earthworks; at least 100 lux at the workplace when performing installation and insulation work; at least 2 lux on passages within the work site; at least 5 lux in the passages to the work site.

At night, lighting of the working pit should be carried out with floodlights or explosion-proof lamps.

Fire safety

When carrying out work, it is necessary to strictly comply with fire safety requirements aimed at preventing exposure to dangerous fire factors, set out in the following regulatory documents:

– RD 13.220.00-KTN-148-15 Main pipeline transport of oil and petroleum products. Fire safety rules at the facilities of Transneft system organizations.

– Standard instructions on the procedure for conducting welding and other hot work at explosive and fire-hazardous facilities in the oil industry.

GOST 12.1.004-91. SSBT. “Fire safety. General requirements";

GOST 12.1.010-76. SSBT. “Explosion safety. General requirements";

Fire safety rules in forests of the Russian Federation. Decree of the Government of the Russian Federation of June 30, 2007 No. 417;

Rules fire protection regime in the Russian Federation. Decree of the Government of the Russian Federation
from 04/25/2012 No. 390

All workers involved in the work must be trained in PTM (fire technical minimum) and undergo fire safety briefings. Initial briefing at the workplace and targeted briefing before starting work should be carried out by the immediate supervisor of the work (foreman, site manager, etc.). Introductory briefing on fire safety should be carried out by a SPB engineer, fire safety instructor.

Engineering and technical personnel of the organizations responsible for carrying out the work must undergo training in a specialized organization according to the fire-technical minimum program. This requirement for the contractor must be included in the special conditions of the contract, in accordance with clause 7.1.7 RD-13.220.00-KTN-148-15.

The work contractor must check the implementation of fire safety measures within the work site. It is permitted to begin work only after all measures to ensure fire safety have been completed.

The contractor's work managers are responsible for compliance by subordinate personnel with the fire safety rules in force at the site and for the occurrence of fires that occur through their fault, in accordance with clause 7.1.17 RD-13.220.00-KTN-148-15.

The provision of work sites with primary fire extinguishing means, depending on the type and volume of work, must be carried out by the work contractor in accordance with clause 7.1.18 RD-13.220.00-KTN-148-15.

Roads and entrances to fire-fighting water supply sources must ensure the passage of fire fighting equipment to them at any time of the day, at any time of the year.

When placing and arranging temporary carriages, be guided by the requirements of section 6.5.9 RD-13.220.00-KTN-148-15.

It is necessary to establish a fire safety regime at the work site in accordance with the Fire Safety Rules in Russian Federation(approved by Decree of the Government of the Russian Federation dated April 25, 2012 No. 390) and
RD-13.220.00-KTN-148-15.

Actions in case of fire

Actions of workers in case of fire

Each worker, when detecting a fire or signs of combustion (smoke, burning smell, increased temperature, etc.) must:

a) immediately report this by phone to the fire department; in this case, you must provide the address of the facility, the location of the fire, and also provide your last name;

b) take measures to evacuate people and, if possible, keep them safe material assets, fire extinguishing with primary and stationary fire extinguishing means;

c) report the fire to the dispatcher (operator) of the facility or the manager of the facility (senior official of the facility).

Managers and officials objects, persons duly appointed responsible for ensuring fire safety, upon arrival at the scene of the fire must:

a) report the occurrence of a fire to the fire department, notify the management and duty services of the facility;

b) if people’s lives are threatened, immediately organize their rescue, using available forces and means for this;

c) check the activation of automatic fire protection systems, if available (fire extinguishing, cooling (irrigation) installations, smoke protection systems, warning systems and fire evacuation control systems);

d) if necessary, turn off the electricity (with the exception of the fire control unit), stop the operation of transporting devices, units, apparatus, and take other measures to help prevent the development of fire hazards;

e) stop all work (if this is permissible according to the production process), except for work related to fire extinguishing measures;

e) remove beyond danger zone all workers not involved in firefighting;

g) carry out general guidance on fire extinguishing (taking into account specific features object) until the arrival of the fire department;

i) ensure compliance with safety requirements by workers taking part in fire extinguishing;

j) simultaneously with extinguishing the fire, organize the evacuation and protection of material assets;

k) organize a meeting of fire departments and provide assistance in choosing the shortest route to access the fire;

l) inform the fire departments involved in extinguishing fires and carrying out related priority rescue operations, information about hazardous (explosive), explosive, highly toxic substances processed or stored at the facility, necessary to ensure the safety of personnel.

Upon arrival of the fire department, the head or person replacing him informs the fire extinguishing director about constructive and technological features the facility, adjacent buildings and structures, the quantity and fire hazard properties of stored and used substances, materials, products and other information necessary for the successful elimination of the fire, the operation of the emergency control system, emergency systems, and also organizes the involvement of the forces and resources of the facility in the implementation of the necessary measures related to the liquidation fire and preventing its development.

6. Operational quality control scheme

Construction control must be carried out by construction control units of the JCC at all stages of all types of construction and installation works. It is prohibited to carry out construction and installation work without the participation of the JCC. Responsibility for the organization and quality of construction control rests with the contractor.

SKK must carry out construction control during each technological stage of work. The results of construction control are recorded daily in the construction control log of the contractor at the work site, the general work log and the journal of comments and suggestions. The construction control log of the contractor is drawn up in accordance with Appendix B OR-91.200.00-KTN-108-16.

The following measures should be observed:

Written notification from the head of the construction contractor's site (stream) of the responsible representatives of the customer and the quality control body at the work site in a time sufficient to mobilize the customer's quality control specialists, but not less than 1 calendar day, about the start of new stages and types of construction and installation work work, changes in the number of teams (columns) performing work, shifts of work performed, the need to conduct a survey of hidden work, as well as other cases requiring a change in the number and/or qualifications of the customer's insurance company specialists, indicating the responsible representatives of the construction contractor's body and representatives of the quality control service of the construction contracting organization.

Notification of the customer and the inspection body about the need to carry out control measures for the acceptance of completed work 3 working days in advance if it is necessary to present work that requires specialized control and measuring equipment.

Presentation of completed technological operations to representatives of the customer’s inspection body and receipt written permission according to the form of Appendix B in the cases specified in clause 7.2.16 OR-91.200.00-KTN-108-16. In other cases, execution and signing of the AOSR (if provided for in the design/working documentation).

Performing technological operations of the subsequent technological stage only after receiving the appropriate permit in the form of Appendix B in the cases specified in clause 7.2.16 OR-91.200.00-KTN-108-16, issued by a specialist from the customer’s insurance company. In other cases - after registration and signing of the AOSR (if provided for in the design/working documentation), indicating permission to carry out the next stage of work.

7. Familiarization sheet

Item no.	Full name	Employee position	Date	Signature
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The need for and scope of automatic stationary means of detecting and extinguishing fires in cable structures must be determined on the basis of departmental documents approved in the prescribed manner.

Fire hydrants must be installed in the immediate vicinity of the entrance, hatches and ventilation shafts (within a radius of no more than 25 m). For overpasses and galleries, fire hydrants must be located in such a way that the distance from any point on the axis of the overpass and gallery route to the nearest hydrant does not exceed 100 m.

2.3.123

In cable structures, the laying of control cables and power cables with a cross-section of 25 mm or more, with the exception of unarmored cables with a lead sheath, should be carried out along cable structures (consoles).

Control unarmored cables, power unarmored cables with a lead sheath and unarmored power cables of all designs with a cross-section of 16 mm or less should be laid on trays or partitions (solid or non-solid).

It is allowed to lay cables along the bottom of the channel with a depth of no more than 0.9 m; in this case, the distance between a group of power cables above 1 kV and a group of control cables must be at least 100 mm, or these groups of cables must be separated by a fireproof partition with a fire resistance rating of at least 0.25 hours.

The distances between individual cables are given in table. 2.3.1.

Filling power cables laid in channels with sand is prohibited (for an exception, see 7.3.110).

In cable structures, the height, width of passages and the distance between structures and cables must be no less than those given in table. 2.3.1. Compared to the distances given in the table, a local narrowing of passages up to 800 mm or a reduction in height to 1.5 m over a length of 1.0 m is allowed with a corresponding reduction in the vertical distance between cables for one-sided and two-sided structures.

Table 2.3.1. Shortest distance for cable structures

	Smallest sizes, mm, when laying
Distance	in tunnels, galleries, cable floors and overpasses	V cable channels and double floors
Clear height		Not limited, but not more than 1200 mm
Horizontally in the clear between structures when they are located on both sides (passage width)		300 at a depth of up to 0.6 m; 450 at a depth of more than 0.6 to 0.9 m; 600 at a depth of more than 0.9 m
Horizontally in the light from the structure to the wall with a one-sided arrangement (passage width)
Vertically between horizontal structures *:
for power cables voltage:


110 kV and above
for control and communication cables, as well as power cables with a cross-section of up to 3x25 mm and voltage up to 1 kV
Between supporting structures(consoles) along the length of the structure
Vertically and horizontally in the clear between single power cables with voltages up to 35 kV***	Not less than cable diameter
Horizontally between control cables and communication cables***	Not standardized
Horizontally in the clear between cables with voltage 110 kV and above		Not less than cable diameter
____________________ * The useful length of the console should be no more than 500 mm on straight sections of the route. When cables are arranged in a 250 mm triangle. * Including for cables laid in cable shafts.

2.3.124

Laying of control cables is allowed in bundles on trays and in multilayers in metal boxes, subject to the following conditions:

1. O.D the cable bundle should be no more than 100 mm.

2. The height of the layers in one box should not exceed 150 mm.

3. Only cables with the same type of sheaths should be laid in bundles and multilayers.

4. Fastening of cables in bundles, multilayered in boxes, bundles of cables to trays should be done in such a way that deformation of the cable sheaths under the influence of its own weight and fastening devices is prevented.

5. For fire safety purposes, fire barrier belts must be installed inside the boxes: on vertical sections- at a distance of no more than 20 m, as well as when passing through the ceiling; in horizontal sections - when passing through partitions.

6. In each direction of the cable route, a reserve capacity of at least 15% of the total capacity of the boxes should be provided.

Laying power cables in bundles and multi-layers is not allowed.

2.3.125

*. In places saturated with underground communications, it is allowed to construct semi-through tunnels with a height reduced in comparison with that provided in the table. 2.3.1, but not less than 1.5 m, subject to the following requirements: the voltage of the cable lines must be no higher than 10 kV; the length of the tunnel should be no more than 100 m; the remaining distances must correspond to those given in the table. 2.3.1; There should be exits or hatches at the ends of the tunnel.

___________________

* Agreed with the Central Committee of the Trade Union of Power Plant and Electrical Industry Workers.

2.3.126

Oil-filled cables low pressure must be attached to metal structures in such a way that the possibility of formation of closed magnetic circuits around the cables is excluded; the distance between fastening points should be no more than 1 m.

Steel pipelines of high-pressure oil-filled cable lines can be laid on supports or suspended on hangers; the distance between supports or hangers is determined by the line design. In addition, pipelines must be fixed on fixed supports to prevent thermal deformations in the pipelines under operating conditions.

The loads taken by the supports from the weight of the pipeline should not lead to any movement or destruction of the support foundations. The number of these supports and their locations are determined by the project.

Mechanical supports and fastenings of branching devices on high-pressure lines must prevent swinging of branching pipes and the formation of closed magnetic circuits around them, and insulating gaskets must be provided in places where supports are fastened or touched.

2.3.127

The height of cable wells must be at least 1.8 m; The height of the chambers is not standardized. Cable wells for connecting, locking and semi-locking couplings must have dimensions that ensure installation of the couplings without tearing.

Coastal wells at underwater crossings must be sized to accommodate backup cables and feeders.

A pit must be built in the floor of the well to collect soil and storm water; a drainage device must also be provided in accordance with the requirements given in 2.3.114.

Cable wells must be equipped with metal ladders.

In cable wells, cables and couplings must be laid on structures, trays or partitions.

2.3.128

Hatches for cable wells and tunnels must have a diameter of at least 650 mm and be closed with double metal covers, the bottom of which must have a device for closing with a lock that can be opened from the side of the tunnel without a key. Covers must have provisions for their removal. Indoors, the use of a second cover is not required.

2.3.129

Special protective casings must be installed on connecting couplings of power cables with a voltage of 6-35 kV in tunnels, cable floors and channels to localize fires and explosions that may occur during electrical breakdowns in the couplings.

2.3.130

End couplings on high-pressure oil-filled cable lines must be located in rooms with positive air temperatures or be equipped with automatic heating when the ambient temperature drops below +5°C.

2.3.131

When laying oil-filled cables in galleries, it is necessary to provide heating for the galleries in accordance with the technical specifications for oil-filled cables.

The premises of oil feeding units of high pressure lines must have natural ventilation. Underground feeding points may be combined with cable wells; in this case, wells must be equipped with drainage devices in accordance with 2.3.127.

2.3.132

Cable structures, with the exception of overpasses, wells for connecting couplings, channels and chambers, must be provided with natural or artificial ventilation, and the ventilation of each compartment must be independent.

The calculation of ventilation of cable structures is determined based on the temperature difference between incoming and exhaust air of no more than 10°C. At the same time, the formation of hot air bags in narrowing tunnels, turns, bypasses, etc. must be prevented.

Ventilation devices must be equipped with dampers (dampers) to stop the access of air in the event of a fire, as well as to prevent freezing of the tunnel in winter. The design of ventilation devices must ensure the possibility of using automatic shutdown of air access to structures.

When laying cables indoors, overheating of the cables due to increased ambient temperature and the influence of technological equipment must be prevented.

Cable structures, with the exception of wells for connecting couplings, channels, chambers and open overpasses, must be equipped with electric lighting and a power supply network portable lamps and tool. At thermal power plants, the network for powering the tool may not be installed.

2.3.133

Cable laying in collectors, technological galleries and along technological overpasses is carried out in accordance with the requirements of SNiP Gosstroy of Russia.

The shortest clear distances from cable overpasses and galleries to buildings and structures must correspond to those given in Table. 2.3.2.

The intersection of cable overpasses and galleries with overhead power lines, intra-plant railways and roads, fire passages, cable cars, overhead communication and radio lines and pipelines is recommended to be performed at an angle of at least 30°.

Table 2.3.2. The shortest distance from cable overpasses and galleries to buildings and structures

Construction	Normalized distance	Smallest dimensions, m
When following in parallel, horizontally
Buildings and structures with blank walls	From the design of an overpass and gallery to the wall of a building and structure	Not standardized
Buildings and structures with walls with openings
In-plant non-electrification quoted railway	From the design of overpasses and galleries to the approach dimensions of buildings	1 m for galleries and passage overpasses; 3 m for impassable overpasses
Intra-factory highway and fire routes	From the design of the overpass and gallery to curb stone, outer edge or bottom of a road ditch
Cable car	From the design of the overpass and gallery to the size of the rolling stock
Overhead pipeline

When crossing, vertically
In-plant non-electrified bathroom railway	From the bottom mark of the overpass and gallery to the rail head
In-plant electrified railway	From the bottom mark of the overpass and gallery:
	to the rail head
	to the highest wire or supporting cable of the contact network
Intra-factory highway (fire passage)	From the bottom mark of the overpass and gallery to the road surface (fire passage)
Overhead pipeline	From the structure of the overpass and gallery to the nearest parts of the pipeline
Overhead power line	From the design of the overpass and gallery to the wires
Overhead communication and radio link	Same	1,5

Location of overpasses and galleries in hazardous areas - see Chapter. 7.3, location of overpasses and galleries in fire hazardous areas - see Ch. 7.4.

When running parallel overpasses and galleries with overhead communication and radio lines, the shortest distances between the cables and wires of the communication and radio lines are determined based on the calculation of the influence of cable lines on the communication and radio lines. Communication and radio wires can be located under and above overpasses and galleries.

Minimum height of cable overpass and gallery in impassable part of the territory industrial enterprise should be taken from the calculation of the possibility of laying the bottom row of cables at a level of at least 2.5 m from the planning ground level.

Page 1 of 2

On cable structures, wires and cables are laid openly along walls and ceilings.
Before installation, inspect the condition of the cables on the drums. Then, using a megohmmeter, the integrity of the core insulation is determined.
For laying cables, supporting structures are used, assembled from perforated metal profiles, and fasteners (staples, bolts, nuts and washers). Single cables are laid on hanging hooks fixed in racks (Fig. 1).
Cables with an outer diameter of more than 18 mm, laid horizontally or vertically, must have supports 4-10 m long. In this case, cables laid in horizontal straight sections are not secured to supports, and cables laid in vertical sections are secured to each support.
Regardless of the arrangement of the supporting cable structures, the cables are fixed at a distance of no more than 0.5 m from the junction boxes, couplings and end seals.

Rice. 1. Prefabricated cable structures of the “Christmas tree” type: a - stand; b - shelf; c - bracket; g - suspension; d - fire-resistant partitions; e - stand with pendants; 1 - language; 2 - shank; 3 - oval hole in the shank; 4 - cable; 5 - asbestos-cement partition; 6- connector; 7 - suspension
When securing unarmored cables, be careful not to damage their sheath. To do this, use elastic spacers under the supports and brackets, which should be 5-6 mm wider than them.
Cables with a polyvinyl chloride sheath running indoors are laid in places where they cannot be damaged by rodents, or protected with boxes or meshes.
Cable structures of the “herringbone” type, manufactured in factories, consist of perforated racks and shelves. Trough-shaped racks are made from sheet steel 2.5 mm thick and 400, 600, 800, 1200 and 1800 mm high. Depending on the height, the racks have 8, 12, 16, 24 and 36 shaped holes for placing cable shelves with different or equal distances within the same rack.

Rice. 2. Installation of cable structures:
a - wall-mounted; b - ceiling-mounted, single-sided; a - ceiling-mounted, double-sided; g - block (double) structures; 1 - shelf; 2- stand; 3 and 4 - corners

Cable shelves are manufactured in lengths of 160, 250, 350 and 450 mm. The oval holes of the shelves allow cables to be fastened at a certain distance from each other; the special design of the shelf-rack joint does not require welding (with the exception of structures used for vertical cable routing).
Cable structures are painted or galvanized. Galvanized structures are used in outdoor installations, in damp, especially damp and hot rooms, as well as in rooms with a chemically active environment of internal electrical installations, in cable mezzanines, basements and tunnels (regardless of the environment), in other cases painted structures are used.
Cable structures with hangers consist of racks and embedded hangers. Racks with a height of 600, 800, 1200 and 1800 mm are manufactured at the MEZ by transverse cutting of factory-made perforated profiles (channels). When assembling structures, embedded hangers of three standard sizes are inserted into the oval holes of the racks with the narrow side of the shank, and then rotated 90° to a horizontal position.
When laying cable lines, they strive to combine routes, combining cables into common streams placed on common structures. In this case, cable structures are installed along the walls of rooms and cable structures, and also suspended from ceilings, beams and other building elements of buildings.
Depending on the installation method and the number of cables to be laid, single and block structures from racks and shelves or racks and embedded hangers are used: wall, ceiling, single-sided and double-sided, double (Fig. 2). In wall and ceiling blocks, cable structures in the MEZ using General connections(purlins) are combined into sections of transportable length (up to 6 m).
Cable structures, depending on their installation location in rooms and cable structures, are secured by welding to embedded elements or metal structures.
Cable racks can be attached to building foundations by shooting dowels using special overhead brackets.

Technical conditions for laying cable lines.

Cable lines must be constructed in such a way that during installation and operation the possibility of dangerous mechanical stresses and damage occurring in them is excluded. To this end:
the cables are laid with a reserve length sufficient to compensate for possible soil displacements and temperature deformations of both the cables themselves and the structures along which they are laid;
cables laid horizontally along structures, walls, ceilings are rigidly fixed at the end points, directly at the end seals, on both sides of bends and at connecting and locking couplings;
cables laid vertically along structures and walls are secured in such a way that deformation of the shells is prevented and the connections of the cores in the couplings are not broken under the influence of the cable’s own weight;
the structures on which unarmored cables are laid are made in such a way that the possibility of mechanical damage to the cable sheaths is excluded; in places where the sheath of these cables is rigidly attached, they are protected from mechanical and corrosion damage by elastic gaskets;
cables (including armored ones) located in places where mechanical damage is possible (movement of vehicles, machinery and cargo, accessibility for unauthorized persons) are protected in height by 2 m from the floor or ground level and by 0.3 m in the ground;
cables are laid from heated surfaces at a distance that prevents them from heating above the permissible level, while protecting the cables from breakthrough of hot substances at the installation sites of valves and flange connections;
cables are protected from stray currents and soil corrosion;
the designs of underground cable structures are selected taking into account the mass of cables, soil, road surface and load from passing traffic;
when laying cables, they maintain certain bending radii;
when laying cables on vertical and sloping areas the routes take into account the maximum permissible level differences;
Tensile forces when laying cables and pulling them in pipes are limited depending on the mechanical stresses permissible for conductive cores and sheaths.

Rice. 3. Fastening cables to structures:
a - one with a diameter of 22-34 mm with a single-leg bracket; b - one with a diameter of 12-60;. mm two-legged bracket; a - two staples with a diameter of up to 20 mm; g ~ two overlays with a diameter of more than 20 mm; 5 - three 12-20 mm staples; 1 - cable; 2 - single-leg bracket; 3 - bolt; 4 - cable shelf; 5 - Thai;
6 and 7 - two-legged brackets; 5 - overlay
To compensate for temperature changes in cables and structures along which they are laid, in cable structures and production premises cables are laid with a margin of 1-2% of the total length of the route.
To rigidly secure cables laid horizontally across structures, staples, clamps or pads are used, the size of which is selected depending on the outer diameter of the cables (Fig. 3). On vertical sections of the route, the distance between the points of rigid fastening of the cables is taken equal to 1 m.
In places where unarmored cables with a lead or aluminum sheath are rigidly attached to structures, elastic gaskets made of non-flammable material (for example, sheet asbestos, sheet polyvinyl chloride) are used. Unarmored cables with a plastic sheath or plastic hose are attached to the structure with brackets (clamps) without gaskets. To protect cables in places where mechanical damage is possible, cut steel pipes or sheet metal casings are used.
The radii of the internal bending curve of cables during installation are allowed at least in the following multiples relative to their outer diameter:
stranded in a lead sheath. . . , . ... , 15
single-core in aluminum or lead sheath and multi-core in aluminum shell. . . . , . . , . 25
with plastic insulation in an aluminum shell... 15
plastic and rubber insulation:
single-core. ..... . ,.,......, 10
stranded, . .. . . . -, . . , . 7.5
Excessively sharp bends may damage the insulation and sheathing of the cables. Paper insulation experiences movement and tearing paper tapes. Plastic and rubber insulation breaks when subjected to sharp bends, and wrinkles or cracks appear on the shells.
The maximum permissible level difference between: the highest and lowest points of location of cables with voltage up to 1 kV with paper insulation and when they are pro-; masonry on vertical and inclined sections should be no more than 25 m. The difference in levels for cables with plastic and rubber insulation is not limited.
The limitation of the level difference between the highest and lowest points of the cable location is associated with the movement of the impregnating composition. This happens in a barely: blowing manner. The cable cores heat up electric shock and volumetric expansion occurs of all materials from which the cable is made. The impregnating composition has the highest coefficient of volumetric expansion of the materials included in the cable structure. Therefore, it is filtered through the cable paper, penetrates the metal sheath and creates overpressure in the cable, leading to stretching of the sheath and an increase in its volume. In a cable laid vertically or obliquely, under the influence of gravity, the impregnating composition flows down (between the wires of the cores, along the surface of single-wire cores, in the gaps between the paper insulation and the sheath), as a result of which an excess amount of impregnating composition accumulates in the lower part of the cable, and in In the upper part, voids are formed filled with volatile substances and gases. The greater the difference in levels between the highest and lowest points of the cable, the higher the hydrostatic pressure of the column of impregnating composition on the metal sheath of the cable and the end coupling or seal. Under significant pressure, deformation of the shell, disruption of the tightness of the end seal, and, as a result, leakage of the impregnating composition may occur. Availability in cable insulation air and vacuum inclusions are accompanied by a sharp deterioration in electrical strength. When using cables with aluminum sheaths, which have a higher mechanical strength, the maximum permissible level difference increases.
For cables with depleted insulation, the maximum permissible difference in levels increases to 100 m with lead sheaths and is not limited with aluminum sheaths.
The specified level difference is not limited for cables with paper insulation impregnated with a non-drip compound.
Cables are laid, as a rule, at positive ambient temperatures. Unwinding, carrying and laying cables during negative temperatures carried out after preheating.

The listed products are primarily used for fastening and mounting trays, perforated profiles, boxes and other structures intended for laying cable routes and wires.

Such products create a single structure that makes it possible to simply and highly reliably mount both elements of electrical structures under the cable and the cable itself on ceilings, walls, floors, load-bearing beams, columns, etc. Examples of installation of load-bearing structures.

Cable shelves and racks are used when laying routes, wires, lines from trays in a horizontal position (on columns, walls, etc.), when designing a route in several tiers.

The GEM standard rack is attached to the load-bearing surface (vertical) using brackets. A minimum of two staples are required to secure one element. The shelf is installed in it using the K1156 key and a dovetail.

In the graph below you can see the comparative load characteristics of load-bearing structure models.

Load-bearing structure “rack-shelf”

Load characteristics load-bearing structure"stand-shelf"

Types and application of racks

Models K1150-K1155 are used to install shelves. They differ in length and, accordingly, in the number of holes. They are attached to a wall or column using brackets K 1157. TO metal elements The structure can be fastened by welding. Perforation holes for fastening shelves are spaced at 50 mm intervals.

	WxHxD, mm		Length L, mm	Weight, kg
K1150	60x26x400	8	400	0,75
	60x26x600
	60x26x800
	60x26x1200
	60x26x1800
	60x26x2200

Analogues of the described models are cable racks S-400 and S-2200.

	WxHxD, mm	Number of holes for installing shelves	Length L, mm
S-400	60x26x400	8	400
	60x26x600
	60x26x800
	60x26x1200
	60x26x1800
	60x26x2200

For installing cable shelves, the perforation has certain differences: there is no fixing tab.

Cable shelves models K1160-K1164

The shelves have different lengths and different load capacities. Made with perforation. Its pitch is 30 mm, the hole has a size of 10 * 20 mm.

	Dimensions, mm			Weight, kg
				Weight, kg

Before laying cables, mark the laying route and strengthen the fastening structures. Pipes are installed in places where there are passages through walls and ceilings. If cable sections along with couplings and end seals are prepared according to measurements centrally in workshops, then instead of pipes, openings are left for the subsequent installation of detachable ones; protective covers.

Paper- and plastic-insulated cables passing through walls and ceilings of buildings can contribute to the spread of fire.

To protect against the passage of fire from one room to another, passages through walls and ceilings are sealed after installation with non-combustible materials. So that the passages can be easily cleared in case of cable changes, easily pierced solutions are used, for example cement grade 300 - 500 s sand 1:10 by volume, or clay with sand 1:3 by volume, or clay with cement and sand 1.5:1:11 by volume.

Cable entries into buildings are usually part of the cable line, and only in some cases (cramped places) cable entries into buildings are made from the nearest

supports overhead line. Figure 60 shows the head of the reinforced concrete support V L 0.4 kV (end), from which the cable entry is made. In addition to the cable termination mast for a four-wire cable (4 KM), arresters for protection against atmospheric surges (RVN-0.5) and an outdoor lighting lamp (SPO-200) are also installed here.

The grounding conductor of the cable sleeve is connected to the upper grounding terminal of the support (rack and strut), and the lower grounding terminals of the support are connected to the grounding conductor mounted in the ground. The cable is lowered into the ground along a strut and strengthened

Rice. 60. Installing a cable sleeve on the end reinforced concrete support Overhead line 0.4 kV: 1- support stand; 2 - grounding conductor; 3 - arrester RVN-0.5; 4 - branch clamp; b - cable coupling 4KM; 6 - loop die clamp.

brackets and protected at an accessible height with a steel pipe.

Cable entries into buildings from trenches may, depending on local conditions, have various designs(Fig. 61) If significant soil subsidence is not expected at the cable entry points, then the cable reserve can be left either in the horizontal or vertical plane.

The cable reserve (approximately 1 m) is laid in an incomplete loop. The bending radius must not be lower than that allowed for this brand of cable. The amount of temporary elevation of the backfill above the planning mark, cable reserve, and backfill thickness are taken based on local conditions and depending on the possible amount of soil subsidence. The depth of the cable at the points of entry into buildings must be at least 500 mm.

The diameter of the pipe is selected depending on the thickness of the cable, and the length of the pipe is determined by the thickness of the wall.

To protect against strong soil subsidence, lay
reinforced concrete slab (Fig. 61, b). Hole width in
wall (dimension A): 500 mm for one cable and 650 mm for
two cables. The width of the slab is 500 and 650 mm, respectively
(size).

Rice. 61. Inserting cables from trenches into the building:

a- with small expected soil landings; b - with significant soil subsidence; 1- power cable; 2- slabs or bricks (cable protection); 3- fine earth or sand; 4- sand without admixture of clay and stones; 5 – pipe seal; 6- - concrete grade 100; 7 - waterproofing 8 - pipe; 9 - reinforced concrete slab; A is the width of the hole in the foundation; B is the width of the slab.

When installing a cable entry to a panel or panel installed directly on the wall of the building through which the entry is made, the cable is passed through a curved pipe. Figure 62 shows the designs of such inputs into buildings with wooden cobblestone and log walls. For buildings with brick and reinforced concrete, as well as with frame-fill walls, the input device differs only in the method of fastening to the walls (staples on dowels or wood screws).

The diameter and length of the pipes are determined by the thickness of the cable, the thickness of the walls, and the height of the floor. The smallest pipe bending radius is selected according to the cable grade with the expectation that the cable pulled into the pipe has a bend steepness within the permissible limits (Fig. 55). For example, for the passage of unarmored cables with rubber insulation, the pipe must be bent with a radius equal to at least six pipe diameters, and for cables with plastic or paper normally impregnated conductor insulation, armored or unarmored, with a radius equal to fifteen diameters. For cables up to 20 mm thick, lay a pipe with an internal diameter of 25-30 mm; and for cables up to 30, 40 mm, respectively, pipes with a diameter of 50, 70 mm.

Rice. 62. Options for installing cable entries from trenches into buildings

when the inlet panel is located in the building on external wall:

1 - power cable; 2 - cable protection (slabs or bricks); 3 - seal, pipes; 4 - fine soil or sand; 5 - bushing; 6 - bracket; 7 - protective pipe 1.3 m long; 8 - coupling with grounding nut; 9 - input pipe; A - size from the floor, equal to 1500 mm for wall-mounted panels or 150 mm for floor-mounted panels.

The places where the cable exits the pipe are sealed with cable yarn soaked in oil. If there is no cable strand, then the steel pipes can be sealed with cement. If asbestos cement pipes are used to pass through the walls, they can be sealed with tow impregnated with bitumen. The ends of the pipes are sealed with yarn over a length of 300 mm, with cement over a length of 60 mm, and tow over a length. 150 mm. At low level groundwater You can use clay to wet yarn (cable or hemp). -

The wall at the outlet of the pipe to the outside is covered with coating waterproofing or covered with hydrophobic sand or hydrophobic clay. In dry soils, the hydrophobic layer can be replaced by a layer of pure doughy clay mixed with water.

Instead of pipes, profile metal can be used to protect the cable when it is brought out of the trench onto the wall,

Rice. 63. Exiting the cable from the trench to. wall of a building with channel protection:

1- power cable; 2 - protection of bricks or slabs; 3 - channel; 4 - bracket.

for example a channel (Fig. 63). Distance between cables (size A) 60 mm should be taken for cable thicknesses up to 20 mm, 70 mm for cable thicknesses up to 30 mm and 100 mm for cable thicknesses over 30 mm. The channel can be bent from sheet steel 3 mm thick. The following are the channel dimensions depending on the cable thickness:

Cable thickness, mm Channel dimensions (channel width, shelf width) for one cable, mm. Channel dimensions. and for two cables, mm

Up to 20 - Over 20 Over 30 32X32 50X50 60x60

80x32 120X50 160x60

When reconstructing air inputs of 0.4 kV overhead lines into buildings and replacing them with cable ones using existing passages in the walls of buildings, the input design shown in Figure 64 is used.

Cable entries, if they are well made and properly operated, are more reliable than air entries, since they are not affected by wind and ice, they cannot be closed by throwing wire, or damaged when snow is thrown from the roof. They are safer, since all live parts are hidden under the shell.

Fig. 64. Cable entry into the building when replacing the air entry, using existing passages in the walls of the buildings:

1- power cable; 2 - bracket; 3 - funnel; 4 - sleeve

But it must be remembered that the cable insulation should always be high, and the metal sheaths and protective coatings- reliably grounded.

Inside the building, cables are laid both openly (at a height of at least 2 m) and in the floors - in specially laid pipes, as well as in special trays or channels with a large number of cables. Between walls and columns of buildings, as well as under canopies, cables can be suspended on cables.

Cables laid horizontally in the building are rigidly fixed at the turning points of the route and at the couplings. Cables laid vertically are secured so that there is no deformation of the sheath and connections under the influence of weight on the cable.

Cables protect against heat radiation from various heat sources and from direct action sun rays, with the exception of northern regions (geographical, latitude more than 65 degrees), where protection from solar radiation is not required. The bare cable sheaths are protected at the attachment points with elastic gaskets. If a cable with a jute cover is laid in a trench and brought into a building, then the jute cover is removed from the cable section inside the building.

The pipes through which the cable is removed from the building must be inclined towards the trench and sealed to prevent water from entering the building.

For fire safety purposes, cables without external flammable sheaths or coverings (for example, jute) are used inside buildings.

By wooden structures cables are laid with a gap from the base to the cable of at least 50 mm. There should be gaps between bare aluminum sheathed cables and concrete and brick plastered walls. If such walls are painted oil paint, then the cables can be laid without gaps. If there is a danger of mechanical damage during operation, then use armored cables or protection with boxes, angle steel, or pipes. When the installation height of unarmored cables is less than 2 m, such protection is always required.

Dismantling cable line:

Remove the fertile layer to a separate place. Remove the infertile layer of soil. Remove brick. Delete sand cushion. Remove the cable from the trench and sleeve in the wall.