“PVC” stands for polyvinyl chloride - a material that has good performance at high loads, as well as significant temperature extremes. PVC pipes (white, orange, black, etc.) are very popular in the modern market of communication products. Often, based on them, an external or internal sewage network, a drainage system are built, cold and hot water is connected, and an electric cable is laid.
With the help of PVC pipes, it is possible to organize water supply and sewage for a residential building or public facility without any special costs
Content
PVC: what is it
PVC pipe is highly durable. The material itself belongs to the class of plastics, which upon completion of the formation of the product does not lose the ability to re-process, its melting point is 165-200 ° C. PVC is almost not subjected to mechanical stress and other deformations, which is explained by the structure of molecules and the structure of the polymer.
The material is thermoplastic, it lends itself well to machining, it is easily welded when heated to a temperature of 200-300 ° C. In addition, non-combustible PVC pipes are produced from it. Polyvinyl chloride is not sensitive to many acids, aliphatic, chlorinated and aromatic carbohydrates.
The strength of joints created by welding or gluing is about 85-90% of the same indicator of the material itself. PVC is a good dielectric, that is, it does not conduct electric current. This property contributes to the use of the material in the production of smooth PVC electrical pipes.
Note! If the heating temperature of the pipe is more than 85 ° C, the dielectric features are lost.
The fire safety of PVC pipes determines their use when laying electrical networks for various purposes
PVC pipe is used to protect television, electrical, computer cables from all kinds of damage. High fire resistance of the polymer gives chlorine, which is part of it. The melting temperature of PVC pipes exceeds analogues of polyethylene or polypropylene.
PVC pipe specifications
A comparison of the technical parameters of PVC pipes and other materials is given in the table.
Table 1
| Characteristic | PVC | Fiberglass | Stainless steel | Aluminium alloy | unit of measurement |
| Density | 1,3-1,43 | 1,6-1,9 | 7,7-7,9 | 2,7 | kg / cm3 |
| Elastic modulus | 2,0-2,7 | 17-22 | 210 | 70 | GPa |
| Tensile strength (yield strength for PVC and metals) | 4-7 | 170-227 | 200-226 | 100 | MPa |
| Thermal conductivity | 0,13-1,63 | 0,58 | 17,5-58 | 201,3-221 | W / (K * m) |
Pipe production is based on GOST R 51613-2000, the terminology is established by GOST R 52134-2003, weight, wall thickness and diameters are determined by GOST 18599-2001.
The pipes with the thickest walls can withstand heavy loads and are suitable for industrial use
Products have high elasticity, are resistant to the accumulation of deposits and the formation of rust. The smoothness of the inner surface eliminates the pressure drop, and if it is an electrical pipe (white or gray), it does not interfere with the cable pulling.
PVC pipes are resistant to stray currents, microorganisms, ultraviolet rays.The white pipe is used to protect against electric shock in case of damage to the insulation of the wire.
The minimum wall thickness for a PVC pipe is 1.3 mm; maximum - up to 36.7 mm for products used in industry.
Types of PVC pipes
There are several classification features that determine the assignment of polyvinyl chloride pipes to one type or another. All types of products have different appearance, characteristics and properties. Smooth PVC pipes come in:
- casing;
- sewer;
- electrical engineering.
According to the bending radius of the PVC pipe is flexible, very flexible and rigid, in size - small, medium and large.
For external sewage, those PVC pipes that can withstand the load should be used, because such systems are laid underground
When installing the system in the house, you will need two types of products: PVC external and internal sewer pipes. Pipe division is based on the location of the system. The characteristics of PVC pipes for domestic sewage allow them to be used to drain wastewater from apartments and private houses.
Note! The outer pipe is used for sewage networks with a significant cross-section, as well as for drainage structures.
The characteristics of the working environment is another classification feature. According to it, the pipes are divided into pressureless, used to supply media without pressure, and pressure pipes, which provide for the creation of pressure. There is also a type of pipe that transport rarefied media. Corrugated pvc pipe (black, white, gray) can often consist of two layers - the outer corrugated and the inner smooth.
GOST 28117-89 defines the assortment of pipes made of polyvinyl chloride. Information on PVC pipes (what it is, decoding of conventions, assortment, requirements for production and use, technical parameters and features) can be found in regulatory documents.
Characteristics and features of flexible PVC pipes
Often there is a flexible pipe, the technical characteristics of which are determined by the properties of PVC. Such products have a high ring stiffness. Thanks to this, the flexible pipe can withstand pressure up to 120 atm. When heated, the elongation of the product is 5%.
Since the frost resistance of the material is low, thermal insulation is required. A flexible pipe is not able to maintain its properties if the temperature is below -15 ° C.
A flexible pipe also has high strength and resistance to stress, but its scope is limited to a certain temperature range
Polyvinyl chloride has a high light transmission. For this reason, a flexible pipe is often transparent or painted in various colors. Products from such a polymer have a higher resistance to ultraviolet than other plastics. They are very smooth inside and out. If the temperature exceeds +78 ° С, the stiffness of the flexible pipes decreases.
Socket and square PVC pipes
A square PVC pipe with a wall of 2 to 3 mm is used for the construction of greenhouses and greenhouses. From PVC pipes, a frame is made and attached to a wooden foundation. In agriculture, a square pipe is used to create and connect nipple watering systems.
This shape of the pipeline holds the entire system upright, which is difficult to implement with round products. In this case, it is very important to ensure the perpendicularity of the installation of the nipple to the line on which the square pipe is placed. The range of products involves their release in different sizes and wall thicknesses.
Note! Standards do not prohibit staining profiles by adding pigment. So it turns out, for example, a white or orange pipe.
PVC bell-shaped pipes differ from other types of products by the presence of a bell, which is equipped with a sealing ring.Such a structure allows not to use welding equipment during installation of the system. Socket pipe is applicable for water supply and sewage network. It is made of unplasticized polyvinyl chloride, which is durable and resistant to aggressive environments.
Bell pipes are easy to install, for which no tools are needed
The bell-shaped pressure pipe has a wide range. The operating pressure range is presented in the table.
table 2
| Size ratio | Pressure | unit of measurement |
| SDR41 | 0,63 | MPa |
| SDR33 | 0,8 | |
| SDR26 | 1,0 | |
| SDR21 | 1,25 | |
| SDR17 | 1,6 |
The socket pipe joins with other products with the formation of a tight connection, which is not affected by reduced or excess pressure in the pipeline.
Features of the choice of pipes
Particular attention in the selection of products is given to marking PVC pipes. The decryption is simple. Usually indicated:
- type of PVC;
- type of bell;
- size ratio;
- outer diameter value;
- wall thickness;
- appointment;
- manufacturing standard.
The color decoding of the PVC pipe is as follows: gray (or black corrugated) - for internal sewage systems; orange or yellow - for external networks; polyvinyl chloride casing pipe - white or blue. The inner surface of the corrugated PVC pipes is white or light gray.
Pipes used for casing wells are most often produced in white or blue
Additional characteristics of PVC pipes can always be found in the documents for its manufacture.
According to the strength class of the product are divided into 3 groups:
- light (L);
- average (N);
- heavy (S).
The permissible depth of its occurrence when laying the pipeline underground depends on whether the pipe belongs to a particular strength class. The lightweight group can withstand 2 kN / m2 and is designated SN-2, average - 4 kN / m2 (SN-4), heavy - 8 kN / m2 (SN-8).
Black PVC pipe is commonly used for open laying of cables and wires. This color reduces exposure to ultraviolet rays.
Use of PVC pipes
Due to its technical characteristics, PVC pipes have a wide range of applications, which is determined by their type. Products can be the basis of public water supply, where the temperature of the working fluid is up to 45 ° C, as well as pressure and gravity domestic sewage.
Due to the properties of PVC pipes, sewage or water supply based on them will be reliable and durable
Structurally, the reinforced PVC pipe is a spiral frame filled with polyvinyl chloride. It is used in industrial and household equipment with a high level of vibration. The main purpose of such products is to protect the power supply circuit in equipment that is subjected to prolonged vibration loads.
The structure gives the reinforced PVC pipe flexibility and increased strength. Such features allow the product to be used in other conditions that are characterized by long-term static loads. This can be, for example, underground and hidden laying in building materials. It is also permissible for reinforced PVC pipes to use an external installation for protecting electrical networks.
Note! Due to its flexibility (at least two external diameters), the product can be used in areas that require bends and turns.
Smooth rigid PVC pipe is widely used in the installation of sewers and the laying of electric cables. The light series is suitable for open cable wiring to the base with any degree of flammability, as well as hidden - in floors, walls, ceilings. The heavy series is suitable for placement in concrete and cement screeds.
Before deciding on the application, you should study all the information about PVC pipes: what is it; what are their technical and operational characteristics; how to decipher their markings; which is better - white, orange, gray, black or other information.The assortment of PVC pipes allows you to choose the most suitable option for specific requirements.
