Choosing pipes for wiring - types, advantages and disadvantages

Wiring in pipes has been widely used in the West and in China for several decades. In our country, this technology, especially in private construction, is only beginning to be mastered, but has already received a lot of positive feedback from ordinary consumers.

Electrical pipes - what is it, the purpose and advantages of

Laying wiring with steel tr

wiring Electrical wiring pipes are products made from various materials used to protect the electric wire from mechanical stress, dampness, low temperatures and other adverse weather conditions.

In addition to protecting the cable, using them allows you to solve the following problems:

• Repair — if there is a problem with the power grid, it is easier to diagnose it and fix the problem on a specific line. Due to the improved insulation and natural ventilation inside the pipe, the total number of problems is reduced several times.
• Safety - pipes made of non-combustible materials allow laying electrical wiring in wooden houses and other buildings with high structural fire danger.
• Service life - resistance to aggressive effects, an additional layer of insulation and other factors make it possible to achieve higher material integrity over several decades.

The need for application is determined by the project and the technical conditions in which the power grid will be operated. For example, in panel houses, all electrical wiring is located in plastic pipes. Material of the required length is laid in the formwork during the manufacture of the panel. Electricians can only lay the wire in the already finished cable channel.

Types of pipes for electrical wiring

Smooth, corrugated and reinforced types of various materials are used to protect and insulate electrical wiring: steel, galvanized metal, copper, PVC, HDPE.Each variety has its advantages, disadvantages and scope, which are taken into account when designing communications.

Steel

Steel pipe for electrical wiring and output circuit to junction box

Thin-walled and corrugated metal pipes for wiring. For the production of thin-walled used mild steel SUS 304L with an admixture of chromium and nickel. The high content of chromium( 18%) makes it possible to actively resist the corrosion process, while maintaining sufficient ductility.

In conditions with constant high humidity and humidity, a galvanized pipe of similar composition is used. Galvanization is performed both inside and outside the product, including the weld. Bending it up to 2.5 cm is made by an ordinary manual pipe bender.

Specifications for thin-walled tubes are regulated by the standard. In America and China adopted the international standard EMT.In Russia, the production of longitudinal welded steel electric pipes is regulated by GOST under No 10704–91.Characteristics of materials manufactured according to the EMT standard can be seen in the photo below.

Flexible steel corrugated pipe is a product of cylindrical shape of variable diameter. It was developed in Japan more than 20 years ago as a product having free flexibility and mobility with high seismic activity.

Characteristics of galvanized pipe for wiring

Currently used in conditions where stainless steel is required, able to withstand repeated bends without changing the internal diameter and integrity.

The main scope of their application is the installation of electrical wiring in wooden houses, standard apartments with wooden floor decks and other wooden structures, as well as damp rooms with a chemically active medium. The metal provides high security of communications when they are laid in the immediate vicinity of combustible materials.

Copper

Electrotechnical copper pipe for wiring

Copper and brass products for wiring are manufactured in the form of thin-walled tubes, soldering boxes, corners 90o, connecting sleeves, fasteners, etc.where increased safety requirements are imposed: wooden houses, public places, museums, libraries, light and medium industry.

When compared with conventional steel, copper has a number of advantages:

• Durability - copper and brass are not subject to corrosion processes, which makes it possible to use them in conditions with a constant humidity of more than 70%.
• Installation - copper is a very soft and flexible material, which increases the speed of laying communications.
• Decorative - polished or artificially aged copper has high decorative qualities.

Due to their high cost, copper pipes are not widely used. Most often they are used only in certain conditions when products that meet modern safety standards in combination with high decorative qualities are required.

Plastic

Rigid electrical engineering plastic pipe for wiring and its characteristics

Seamless smooth wall plastic pipes are the most popular solution for flush-mounted electrical wiring. They are mainly used in conditions where increased resistance to mechanical stress and humidity is required, as well as for insulation of equipment operating at voltages up to 1000 V.

Among their other features, you can highlight:

• Ease of installation - no welding machine or other complex equipment is required for installation. During installation, various additional elements are used, which speeds up the installation work.
• Resistance - plastic is not susceptible to corrosion and endures the effects of aggressive environment. This type is allowed to apply when installing wiring in the ground and water.
• Low weight - the lightness of the products facilitates the process of transportation and installation, especially during the construction of apartment buildings and public spaces.
• Lifetime - most manufacturers give a guarantee for their products from 5 to 15 years. The average life of plastic pipes subject to quality installation of at least 25 years.

PVC and HDPE is used for the manufacture of plastic electrical pipes. Thin-walled PVC pipes are made of non-combustible polyvinyl chloride. They have high mechanical strength, minimal expansion during operation, a large selection of diameters, mounting adapters and other fittings.

Electrical HDPE pipes are made of high pressure polyethylene. Products are distinguished by high resistance to corrosion and rotting processes, they are not afraid of high humidity and aggressive environmental influences.

When overhauling or laying new wiring inside the building, polyvinyl chloride pipes are mainly used. They have a small wall thickness and an optimal ratio of technical characteristics, which makes it possible to use them in conditions of constant contact with the power cable. In the case of wiring in the open air and in rooms with high humidity, use polyethylene pipes.

Flexible Corrugated

PVC corrugated pipe for wiring

Electrical plastic corrugation is made of non-combustible polymer composite. The corrugation has a variable cross section due to the alternation of pipe sections having different diameters. Areas with thin walls are responsible for the flexibility and elasticity of the product, and thick-walled - for rigidity and resistance to shock.

Corrugated pipes are most often used for interior work when installing wiring from a low-combustible cable in rooms with a complex layout. The maximum voltage of the network is not more than 1000 V. It is not recommended to use a corrugation in the open air and in rooms where direct sunlight is possible.

According to the degree of load, the following types are distinguished:

• light - a load of no more than 350 N per 5 cm is provided. They are used for mounting communications over open areas of the ceiling, raised floor and walls.
• heavy - the maximum permissible load is not more than 750 H by 5 cm. Used for installation and insulation of electrical wiring under the concrete layer.
• super heavy - a maximum load of 1250 H per 5 cm is allowed. They are used for laying communications in public places with high safety requirements.

This material is completed with a special broach - it is a steel wire with a cross section of up to 1 mm used to quickly pull out the cable. At the end of the draw, fix the power cable and pull from the back side. This reduces installation time by up to three times.

. Decorative types.

. Decorative conduit pipes for electrical wiring imply thin-walled materials of the EMT standard made of copper, brass and galvanized steel. Mainly used in the interior decoration and interiors in the style of "Loft".

Among the domestic manufacturers of materials with high decorative qualities can be noted the company "EM-T".Their catalog contains a wide selection of pipes themselves, connecting fittings, couplings and other mounting elements.

Pipes for wiring in the ground

Double-walled electrical pipes of low density polyethylene

Previously, when installing the wiring in the ground, metal and asbestos-cement pipes were used for its insulation. The products had a high weight, mechanical strength and corrosion resistance, but did not withstand the conditions at a constant high temperature, as well as a sharp decrease or increase in temperature.

Now, when installing communications in an airless environment, rigid and flexible double-wall pipes are used. For their production is used low-pressure polyethylene.

Among the advantages of double-wall pipes are the following:

• Reliability - the service life of a cable channel and cable route is more than 50 years.
• Durability - double-walled pipes have high seismic resistance, are not afraid of moisture, and have increased resistance to shock and mechanical stress.
• Installation - in addition to pipes, manufacturers offer a wide selection of additional elements and accessories that simplify the installation process.
• Rigid double wall corrugated pipes have increased strength and reliability. Used when laying the power cable and communications of large diameter in areas with high dynamic load.

Flexible double-walled electrical pipes have increased ring stiffness, resistance to mechanical stress and aggressive environment. The flexibility of this material makes it possible to lay the cable route in difficult areas with a large number of obstacles.

Regulating documents

Characteristics of copper decorative pipe and additional elements for electrical wiring

Electrical installation technology is governed by a single set of building codes and regulations that are mandatory for any organization, production or department.

The following provisions are used as regulatory documents:

1. PUE( edition No7) - rules for electrical installations for new and reconstructed buildings with equipment operating at voltages up to 500 kW.
2. SNiP( 2.08.01–89, 2.09.04–87) - regulations that prescribe general provisions, design standards, rules for installation and acceptance of work.
3. PTB( 153–34.0–03.150) - safety rules when conducting electrical debugging.

The production of steel electrical pipes is regulated by GOST under No 10704–91, 10706–76 and the international standard CEI EN under No 50086–1. GOST contains a complete list of characteristics and technical requirements for the product.

Technical and operational characteristics of rigid smooth PVC pipes are governed by the interstate standard adopted in 2014 - GOST 32126.1–2013.The old GOST 50827–95 is no longer valid.

Video on the topic: electrical installation in a typical apartment

Insulation of electrical wiring by means of electrical pipes is a modern and simple technology. With a good electrical layout, their use minimizes the risk of serious problems. This is true for private construction, where the main materials for manufacturing is wood.