For mounting the cold water systems, gas supply and drainage and sewerage pipe systems IPA are used most frequently. Consumers are attracted not only by their low price, but also the durability and ease of installation. We describe in detail what it is - HDPE pipe and give her transcript.
Application area
HDPE acronym stands just. This term refers to low density polyethylene - the material is not afraid of corrosion and which is a superior alternative metal products. In contrast to polypropylene, it is more elastic, less brittle, and is able to withstand even extreme cold to -50 ° C. The working range of negative temperatures -20 ° C, whereas the polypropylene is allowed to operate only at -5 ° C. But even this temperature is already critical for him.
Products from IPA are chemically stable and do not react with the environment, so they are widely used for mounting the cold water piping, including at their tab in the ground. After all, unlike other plastics, IPA has a high tensile strength and is capable of changing the geometry without losing integrity.
Taste and composition of the water passing over them, totally preserved. They are ideal for gas communications and sewer systems. Due to increased resistance to low temperatures and are indispensable IPA pipe laying systems external cold water supply.
Finds use as a high-pressure polyethylene in reclamation. It is used as a drain for removing groundwater. Another advantage of high-density polyethylene is its price. It is necessary that the polymer is much less than the polypropylene.
Tip! It is not recommended to use this type of plastic for surface mounting on the street because of weak resistance to ultraviolet. Therefore, in accordance with GOST keep it to light may be no more than 2 months.
Elevated temperature of the product of HDPE suffer worse - they can be operated in the operating mode to + 40 ° C. The melting temperature of the plastic material is 103 ° C. Therefore, for laying conduits with hot water and heating systems used PEX (cross linked polyethylene connected molecules) and polypropylene repoussage - tubes having a thin layer of glass fiber reinforced.
production Features
Almost half of polyethylene products produced by the polymerization is at low pressure. For this purpose two main ways - a suspension (slurry a mixture of substances) and the gas phase. The third method - polymerization in solution - is used less frequently.
IPA is the raw material for ethylene, derived from oil and gas, purified, containing a small amount of oxygen. For ethylene slurry is mixed with catalysts and titanium chloride radicals aluminum, is heated to 120-150 ° C under reduced pressure of 0.1-2 MPa. To adjust the fluidity in the composition is also administered special additives.
The reactor in which the polymerization process is an apparatus mounted vertically, provided with cooling "water jacket". The apparatus is cooled further by stripping of ethylene, not had time to react with the catalysts. After cooling, it is returned back to the reactor.
When a gas-phase method, catalysts are chromium compounds. In this case, the composition is heated to 90-115 ° C at a pressure of 2.1 MPa. At the output of the mass of high density polyethylene is about 97% of the total. From the solution obtained plastic isolated by removing the compound catalysts, solvents and gases. This process takes place in a continuous centrifuge. Further purification is carried out in a separator and a granulator. The last stage - in a couple of steaming and drying the granules of hot nitrogen.
Range
By purpose HDPE pipes are divided into several groups. To make it easier to distinguish each type painted in a specific color:
- water: for supplying drinking water, painted in blue color; articles black with longitudinal blue prozhiliny able to withstand even freeze without loss of integrity, do not fade in the sun;
- casings for wells: high blue or black;
- Gas: yellow or black with yellow stripes;
- Irrigation: pure black;
- sewage: their color depends on the operating conditions; gray and white are intended for internal use; orange and brown (more rigid and durable) - for the construction of highways outdoors; black - for sewage;
- Drainage: corrugated, flexible and tough to withstand the weight of soil, are stained blue, or green;
- specifications: color depends on the type of working fluid.
Tip! Should pay attention not only to the color, but also marked. After all, according to GOST, the color does not necessarily mean the appointment of pipelines. Unscrupulous manufacturers can apply to products intended only for technical purposes, blue stripes.
Specifications. marking
According to the Standard, such items are not designated IPA letters, and PE (polyethylene). They may be labeled as a stamping and using the printer inks. In this case, must be specified:
- STATE name under which the product has been manufactured;
- the manufacturing company;
- material type (PE);
- strength (density): its index figures are coming for the first letters; e.g., PE100 designation is used for greater strength products; PE80 tubes are not as durable and able to withstand less stress;
- outer and inner diameter;
- wall thickness;
- nominal (operating) the pressure at which the product can be operated;
- maximum pressure;
- manufacturing date and batch number.
In addition to these parameters, the labeling indicates the letters SDR. This strength walls. The numbers following the letters show how the outer diameter corresponds to the wall thickness, i.e. how they will be able to resist pressure fluctuations. The lower the numbers that follow the SDR, the product is durable. But the weight of a HDPE pipe will be significant.
Marking S and following figures are also considered to be an indicator of strength. However, this figure more than a laboratory, and users rarely pay attention to it.
sizes
Key parameters for this type of products in accordance with GOST 18599 are the diameter and the wall thickness (cm. the size of the table). Minimum diameter pipes density PE33 is only 10 mm. The maximum parameter for such articles strength 160 mm. The wall thickness of 2-12 mm. They are intended for systems in which the pressure of only 3.2 MPa.
For products with increased strength PE100 minimum and maximum diameter equal for 32 and 1,000 mm, respectively. The wall thickness for them will be 1-59 mm. For such pipes can put liquid with pressure up to 10 MPa.
TABLE 1 - HDPE Pipes main dimensions with walls strength of PE-80 and PE-100
average cost
When buying a product worth paying attention to the price tag. With the cost of the pipe below the average quality of them is unlikely to be on top. After working at a loss will not be any one company.
The service life of plastics largely depends on the feedstock composition and the average is 50 years. By using the same waste ( "the secondary") - bottles, boxes made of polyethylene and even disposable syringes - even properly mounted water, or sewer system fails after year and a half. Tap water passing through such tubes will have a pungent odor chemistry. Typically, these products have no markings and are made of plastic, uniform in color.
Table 2 - Average price of HDPE pipes of different diameters
| appointment | Outer diameter, mm | The wall thickness, mm | U rev. | Cost, rub.) |
| technical | 16 | 2,0 | m | 10 |
| pressure drinking | 20 | 2,0 | m | 23 |
| pressure drinking | 25 | 2,0 | m | 25 |
| pressure drinking | 32 | 2,4 | m | 47 |
| gas | 32 | 3,0 | m | 58 |
| pressure drinking | 50 | 3,0 | m | 81 |
| Sewer (for domestic sewage) | 50 | 1,8 | m | 74 |
| Pouring | 63 | 3,8 | m | 129 |
| technical | 110 | 6,3 | m | 180 |
| Pouring | 110 | 6,6 | m | 349 |
| Sewer (for domestic sewage) | 110 | 2,7 | m | 102 |
| sewer outdoor | 125 | 9,2 | m | 175 |
| gas | 125 | 9,2 | m | 220 |
leading manufacturers
The Russian manufacturer of PE pipe are engaged more than 100 companies. But the bulk of manufactured products accounted for 6 major companies:
- "Kazanorgsintez": they accounted for 20% of the total produced in the country of such products; range of its much - the company offers pipes of different diameters (10-1200 mm) and destination;
- "Tehstroypolimer": produces a high strength polyethylene pipe for gas and water supply systems;
- "Eurotrubplast": this name unites the whole group "Gaztruboplast" companies "Beltruboplast" plants Klimovskii, Kochanowski, etc .;
- "BalEnergoSistemy": it is composed of both production and trading company dealing with implementation;
- Trading house "Polyplast": the range of products is large enough, it produces gas, engineering and water pipes of various diameters;
- "POLYPLASTIC": has 10 plants located not only in Russia but also in CIS countries; the largest of them Irkutsk.
