Corrugation for cable: the best solution for isolated installation of power grids
Polymer products are becoming increasingly widely used. The ribbed corrugation for the cable has been used not so long ago, but it is the best option of all technological innovations for the protection of power grids. Lightweight, compact and flexible PVC channels retain their shape, displacing outdated technologies. The selection criteria and features of the installation of protective corrugation of polymers should be understood in more detail.
What is Polymer corrugated pipe for cable
The corrugation for electrical wiring is a flexible PVC pipe. Due to their properties, including increased flexibility and elasticity, polymer products facilitate the installation of power grids in hard-to-reach and heavily loaded places. For example, in houses built in earthquake-prone regions, it is easier to protect the electrical wiring insulated in this way during fluctuations.
Protection in the form of polyvinyl chloride pipes is also the possibility of combining several wires in one channel. This method is used for the installation of complex multicomponent wiring, lighting design and stretch ceilings with combined lighting. The scope of application of corrugated pipes is quite wide. Modern enterprises produce several varieties of special-purpose products.
Corrugated PVC pipe for cable is usually of small diameter, which eliminates the need to cut a deep and wide channel for hidden installation. It is produced in bays, in such packaging it is convenient to carry and transport.
Important! Low prices for polyvinyl chloride are an insignificant surcharge for the quality, reliability and speed of electrical installation during the construction of new and reconstruction of old facilities.
Polymer materials, from which the pipe for cable laying is produced, have a lot of positive properties. For example, if a fire occurs due to a short circuit, a rapidly fading polymer prevents the spread of fire.
PVC pipe for electrical wiring is also excellent insulation and safety, which is important not only in residential buildings, but also in industrial conditions. It is much safer to lay a high-voltage cable during repair, knowing that the polymer product protects against electric shock.
Corrugation for wires and its most important properties
The corrugated structure is able to withstand enormous pressure and mechanical load, which no smooth pipe can demonstrate under the same conditions.
The convenience of using PVC corrugations for wiring is beyond doubt. The advantage of insulated mounting is also that it is easy to perform it at any angle, even on the surface of arches and arches.
In hard-to-reach places and on curved sections, it is very problematic to do hidden highways in another way. It is the flexibility of the product that guarantees high-quality installation of the electric cable with the exact repetition of complex bends with any architectural features.
Flexible corrugated pipe of small cross-section makes it possible to install complex joints and turns, up to a 360° turn. The cable embedded in the hidden groove fills it evenly, reducing the cost of plastering surfaces after the initial stage of installation.
In modern construction, corrugated pipes are mounted not only inside buildings, but also outside them, which finds application in the organization of a power supply network for objects with outdoor lighting, especially in rural households. For some time now, the installation of power grids is rarely carried out without the use of flexible insulation. In certain cases, landscape design is taken into account. For example, it is recommended to use a red corrugation for a cable that provides night illumination:
- paths and flower beds;
- pool or fountain;
- baths and saunas;
- artificial reservoir;
- barbecue and barbecue areas;
- covered gallery or terrace.
Convenience in work is an important argument for the use of corrugation for laying cable in the ground and during outdoor work. It is cut with scissors on metal or other suitable devices.
Cable laying in corrugation: types of flexible products
At the moment, a protective polymer sleeve is available for various construction needs, including sewer corrugation and protection for cables of different voltages. Depending on the properties of the polymer and the size of the corrugation for the cable, experts recommend using it for different types of wiring:
- for power cable;
- for low-current networks (telephones, television and computer UTP wire).
Protective corrugation, in accordance with the purpose, is available not only in polymer, but also in metal design. Flexible pipe products differ in material, color and design (for example, there is a double corrugation). A cable is stretched inside the product, often not even one – it all depends on the working conditions and the type of wiring:
- hidden internal;
Useful advice! When buying, pay attention to the thickness and cross-section of the corrugation, so as not to overpay for unclaimed properties. The cable should easily pass inside the sleeve.
There is another type of classification of products – according to the degree of strength:
- light pipes;
Light corrugation is used for flush mounting inside the building (sensitive to ultraviolet light). Heavy and dense corrugated products are produced for laying underground (they are characterized by increased resistance to pressure).
For the convenience of determining the destination, a conditional color designation is used, which is reflected in the table:
|n/a||Corrugation color||Scope of application|
|1.||Gray||Standard electrical wiring|
|2.||White||Computer networks, Internet|
|3.||Green||Telephone or other low-current cable|
|4.||Red||External power cable|
|5.||Blue||In the “underfloor heating” system and flexible water slopes|
|6.||Yellow||Gas supply needs|
|7.||The corrugation is black and brown||Insulated wires of household appliances and other electrical appliances|
This is a common industrial and construction standard, but it is not always adhered to, especially if there is a small stock of the product in the bays in the remainder after a large amount of work.
How is the cable laying in the corrugation and disassembly carried out, is a probe needed
Before the advent of protective flexible PVC pipes for electrical systems, the cable was directly walled up in a recess in the wall. Installation was complicated by the fact that the open ends were screwed to a tire or other support passed through a piece of metal pipe. In case of emergency situations or malfunctions, the cable was removed from under the plaster (with the risk of damage).
Upon careful study of the line of modern offers in this field of application, it becomes obvious that a conventional hollow corrugation and a product with an internal probe are being sold. It is often called a “broach” – and this is its purpose.
Useful advice! Think about how to pass the wire inside the corrugation. The best option is when installing the system it is possible to hook it and quickly stretch it.
The probe, if provided, is always visible inside the polymer tubes. This is a thick metal wire located inside along the entire length. The protective shell for wiring is cut together with the probe as needed.
Using a broach is very simple: hooking the wire with the end of the probe, the cable is stretched through the entire length of the polymer tube. The probe is a guarantee of the convenience of filling the tube with an electric cable. The simplest engineering solution confirms the saying that everything ingenious is simple. Only by stretching the electric cable inside the corrugation to a greater length, you can appreciate the simplicity and wisdom of this solution.
On small-sized sections of corrugated tubes (for example, when there is a need for insulation of the wire connection), the probe is not used.
Attention! Doubtful savings are not justified by purchasing without a probe inside the corrugation for the cable: the price differs insignificantly, and work without a probe slows down almost twice.
The convenience of using the corrugation also lies in the fact that cable protection is performed without special tools and does not require much effort. Only an internal probe and a cutting tool will be needed, after which the cable is placed in the prepared grooves (grooves).
When dismantling the old wiring loop, the corrugated sleeve does not necessarily have to be removed from the groove under the plaster. After removing the wires from the insulating cavity, the probe will no longer be required. The corrugation hidden in the strobe can remain in it, which will eliminate the need to make repairs. It is enough to remove the desired piece of electrical cable by pulling on its end. It is recommended to fill the empty corrugation with foam at the edges.
Technical corrugation for cable and its classification
A variety of corrugations for the cable, diameters, differences in cross-section and thickness allow it to be used for various purposes.
Cable channels: dimensions and classification of products
Cable channels: dimensions and parameters of products. Classification of existing structures by type of material. Average prices and additional components.
Conventional thin–walled products are lightweight, flexible, least pressure-resistant sleeves. Although they are applicable for both external and internal work, most often the sleeve is hidden in specially prepared niches where there is no great pressure. Corrugation is also used:
- inside the frame and false structures made of GCL;
- in stretch and suspended ceilings;
- in the protective wiring of cars;
- when installing vertical metal supports.
High–strength products are heavy PVC pipes that are designed for sufficient mechanical load, including temperature changes and difficult operating conditions. They can be poured into concrete structures, mounted under a large layer of plaster or underground at a shallow depth – when transferring cable to neighboring buildings.
The superheavy corrugation is designed to provide maximum protection of power grids from possible damage. It is used in cases when the wiring is laid in places that require the highest level of security.
The parameters of the protective corrugation for the cable vary – in the range of 16-50 mm in external diameter and from 10.7 to 40.2 mm in internal dimensions.
Recommendations for choosing a product according to its diameter:
- for a closed loop of thin wires connected to coaxial networks, sockets, computer and telephone networks, when installing electrical appliances and alarms, a diameter of 20 mm is sufficient;
- installation of electrical wiring between junction boxes and connection of electrical panels is carried out using products with a diameter of 32-35 mm;
- the cable connection between the floors is up to 40-50 mm.
The material is sold in bays of 25-100 m, most often with a probe or broach, facilitating the filling of flexible sleeves. For the convenience of transportation, the bays are packed in shrinkable polyethylene.
Types of materials:
- ordinary PVC (self-extinguishing polyvinyl chloride);
- the most plastic HDPE (low-pressure polyethylene) used in rotary and curved construction sites;
- LDPE (high-pressure polyethylene) for hidden laying in solid materials that are not subject to fire, polyethylene also goes to the manufacture of the outer shell of a two-layer corrugation;
- PA (polyamide) with maximum protection against moisture penetration;
- PP (polypropylene) for cable wiring in channels of monolithic structures.
Areas of application of superheavy polymer corrugation
Superheavy PVC pipe copes with increased load and pressure when laid in the ground at a sufficient depth. It can protect communications under the roadbed and the foundation of the building, near the supports of bridges and fences. At the same time, the price of cable laying in the corrugation increases insignificantly, mainly due to the costs of more expensive thick-walled pipes used for outdoor work.
If thin corrugated sleeves are laid under the plaster of vertical walls, then a large format is hidden in a concrete ditch – under the roadway, paved parking lot.
Useful advice! It makes no sense to purchase such products because of the increased reliability of super-heavy corrugation, unless difficult operating conditions are assumed.
It is better to buy a PVC product in accordance with the technical characteristics or choose a metal corrugation for the cable, if an increased load is likely.
The choice of this type of product may be dictated by concern for safety when it comes to laying the power grid during the construction of buildings designed for a large crowd of people, such as:
- schools and other educational institutions;
- shopping and entertainment centers;
- hotels and inns;
- hospital facilities;
- monolithic industrial buildings;
- train stations and other transport infrastructure.
The high flexibility of the superheavy corrugated pipe allows the cable to be used on rotary and curved sections for various purposes. Such products are used for additional insulation of electrical wiring from moisture, chemicals and mechanical stress. Polymer outdoor corrugation for cable is characterized by high fire safety, especially if it is made of self-extinguishing PVC. It prevents the spread of fire in case of unexpected ignition due to possible accidents.
Classification of PVC products and metal hose for cable by fire safety level
Recently, the requirements for the use of fire-resistant materials in the construction of infrastructure have been increasing. Experts recommend using corrugated pipes for cable, based on the degree of their fire safety:
Attention! Laying of power grids in explosive buildings is carried out inside flexible metal hoses and materials protected from magnetic fields. Plastic pipes, according to GOST, are not intended for these purposes.
Properties of double-walled electrical corrugation
When choosing products for construction needs, it is important to pay attention to the technical parameters and the availability of certificates. The most reliable is considered to be a double reinforced pipe made of different polymers, having:
- outer ribbed coating;
- smooth inner layer.
These design differences contribute to the strength and plasticity of these products. The increased throughput is provided by a smooth wall inside the HDPE sleeves, which correspond to the diameter of the cables. The products are available in “classic” and combined (HDPE plus LDPE) types.
In reinforced structures, a foil (metal) layer can be used. This provides protection against increased load and mechanical pressure. Rigid double corrugation guarantees a high coefficient of rigidity, reinforced corrugated sleeve made of HDPE is produced with a large cross section. These pipes are designed for difficult operating conditions – under the soil and inside the raised floor, under the stretch floors and inside the cement screed.
Important! Electrical corrugation is prohibited to be used for the transportation of liquid media, for example, to supply hot water to a summer shower or boiler. For such purposes, it is better to use a two-layer piece of metal sleeve.
Advantages and disadvantages of corrugated HDPE pipes
Each polymer product has its undeniable advantages and disadvantages. Among the advantages of protective sleeves, experts note:
- resistance to large temperature ranges (from -30°C to +90 °C);
- the convenience of mounting the corrugation at any time of the year and in difficult climatic conditions;
- sufficient tensile strength due to stiffeners;
- affordable installation and easy cable pulling in corrugation for exterior and interior work;
- plasticity ensures the laying of any contour, in most cases without fittings;
- in case of an emergency and partial destruction of structures, the corrugation stretches or narrows slightly, so that the cable inside does not tear;
- resistance of polymers to corrosion, chemical reagents and soils of various acidity;
- long service life (up to 40-50 years);
- availability (if we talk about metal corrugation for a 16 mm cable, the price per meter is 11-15 rubles.).
Among the possible disadvantages:
- weak resistance to the destructive effects of ultraviolet light in outdoor wiring;
- the probability of fire in unprotected plastic.
How the installation is carried out: clips for corrugation
For the installation of a corrugated structure, a sufficient range of accessories is offered, including a probe for broaching and clips for 16 mm corrugation – the price is within 5 rubles for 1 pc.
Plastic mounting brackets can be combined with nails, if the surface material is suitable for such fastening.
Important! The cost of laying the cable in the corrugation is relatively small – this does not significantly affect the material costs when replacing all systems.
In the grooves (furrows inside the walls), laying is carried out for quickly hardening solutions (alabaster or starting plaster).
Special clips for outdoor mounting are available in different formats – taking into account the diameter of the pipes, for example, clips for corrugation of 20 mm. It is possible to use clamps left over from construction and installation work, especially for laying inside ventilation and other boxes when combining communications.
It is quite possible to organize the protected installation of hidden communications with your own hands, if the corrugated product is correctly selected in diameter. To do this, they will pre-cut the wall, making a marking with a special tool to make a groove. The approximate price of laying a cable in a corrugation per running meter is specified by a specialist of a construction company. The dimensions and cost of laying the cable in the corrugation are reflected in the estimate in advance.
The open type of cable installation is carried out behind the walls of the GCL and behind the stretch fabric, using staples and special clips. They are installed at the same interval, eliminating sagging on a horizontal surface. The cable inside the underfloor heating is mounted on a special grid.
As you can see, before purchasing protective products for electrical wiring, it is worth taking into account all the characteristics and clarifying how to stretch the cable into the corrugation. When laying the electric cable inside the corrugation on a large segment, it is desirable to have a probe to simplify the broaching. The superheavy double corrugation is applicable only for underground cable laying and inside the floor with increased load. In domestic conditions, self-installation of light products is available if the cable cross-section is smaller than the diameter of the corrugated sleeve.