When laying new electrical wiring or repairing old ones, experts recommend placing it in a protective shell. For wires and cables, plastic corrugation is used more often than other materials. It is a hose with a circular cross-section and a ribbed surface, which increases the flexibility of the pipe. It is made from different materials, which affects the characteristics of the corrugation.
Content
- Purpose and types
- Suitable material
- Choice of corrugation
- Installation of pipes
Purpose and types
Corrugated hose is used to cover cables for fire safety reasons and to protect wiring from mechanical damage. Wooden or frame walls are highly flammable, like PVC or lining with which they are finished. In this case, a non-combustible corrugation for the cable is purchased. It will protect electrical wiring from fire, even in the event of a fire.
Plasterboard is often used to cover the walls, since the material allows you to easily install cabinets, shelves, and hang pictures. Wires are placed in pipes so that they are not damaged while drilling the walls. If the cable is buried under the floor, it can deform during screed or when poured with concrete. The corrugated wiring is easy to remove and replace in case of damage.
The pipe will protect the cables from exposure to ultraviolet radiation and moisture when laying outside. If the wiring will be located in an open space, then it is necessary to choose a corrugation that is resistant to temperature changes. Reinforced material is useful if the cable is suspended. Underground laying requires a tougher waterproof shell.
Corrugated pipe for cable is divided into types according to the degree of strength:
-
lightweight; - medium;
- heavy;
- reinforced.
The lightweight material is the most flexible, its thin walls are suitable for protecting wiring under walls and ceilings. It practically does not withstand mechanical stress. The middle corrugated pipe will be a little thicker, it is useful for laying in walls and screed. The heavy type has little flexibility, the wall thickness is high. It is used in screeds and underground, couplings or corners are added at the places of turns.
Pipes protect the wires well from moisture, dirt and dust. Reinforced sleeves are made of twisted metal wire and plastic. This is the most durable option, which is laid in the ground or suspended.
A distinction is also made between pipes with and without ties. A wire is tied to the end of the cable, pulled by its other side, placing the cable inside the corrugation. Without a broach, it is difficult to place the wire inside the sleeve. It is better to use a two-layer pipe, in which the inner surface is smooth and the outer surface is ribbed. This is an expensive material, but it is easy to pull the wiring into it.
Suitable material
The corrugated pipe for the cable is made of different materials. There are several types of casing, choose them depending on the conditions of use. The most famous sleeves:
- polypropylene;
- polyvinyl chloride;
- polyethylene;
- steel.
PPR corrugation for wires is usually blue, does not ignite or smolder, and is highly resistant to water. It is used for open laying and in rooms with high humidity levels. The product is made of gray PVC, installed only in dry rooms, as it does not interfere with leaks. Orange or black polyethylene pipes are water and chemical resistant.
The most durable - metal sleeves, they are not susceptible to moisture, fire, temperature changes.
Choice of corrugation
The diameter of the sleeve ranges from 15 to 65 mm, but there are only two parameters - external and internal. If a group laying will be carried out, then half of the space should remain free in the pipe. The wires can heat up and expand. The choice of diameter depends on the area of application:
-
15 mm - lighting devices; - 2 cm - sockets and switches;
- 25 mm - for shields and junction boxes;
- 30 mm - connection of electrical panels;
- 4 cm - passage through several floors;
- 25-30 mm - low-current telephone line and Internet cables.
The diameter of the sheath depends on the number and cross-section of the cables. The correspondences are indicated in a standard table, which can be easily found on the net. Smaller pipes cannot be taken, but larger ones are allowed.
Installation of pipes
For open installation, you need to use special clips that secure the corrugation. They are attached to the walls at the same distance using self-tapping screws. Then a pipe is put into the clips and pressed firmly. You can also secure the sleeve with plastic ties or tin strips with nails.
When laying, some features of the work are taken into account:
-
the maximum length should not exceed 25 meters, while there can be no more than four turns; - the distance between the bends must be up to 4 m, otherwise junction boxes must be installed;
- the turn is at a right angle with a large radius;
- if several cable routes are laid nearby, then a 20 cm gap must be left between them.
In the room, the corrugation is attached between the distributors, from which they lead to switches, lamps and other areas. One cable is easy to lay in a sheath, several wires are fastened with insulating tape or construction tape. In the apartment, you must first install a corrugated pipe, then stretch the wires. On long sections, they do everything the other way around - they lay the cables, and then the sleeve is attached.
