- Types of polypropylene pipes
- What are reinforced pipes?
- Operating pressure
- Diameter of pipes
The key element in the water supply and heating system is the pipes. It depends on them how good the heating will be, and how long the water supply system will be. That is why today, cast-iron pipes are no longer in demand, as before, because they are heavy, difficult to install and are susceptible to corrosion. A newer version, metal-plastic pipes, is devoid of all these drawbacks, but when they are assembled, a huge number of joints, which can adversely affect the performance of the heating system or water supply. The most modern and reliable option at the moment is polypropylene pipes, but to get the maximum benefit from their use you need to choose the right option.
Polypropylene pipes confidently displace metal pipes from the market and become one of the most demanded materials today for the arrangement of a heating or heat supply system. All this is due to the combination of their positive qualities. So, they are not afraid of corrosion, they easily withstand high pressure, they are simple in installation, they differ in small weight. In addition, they are durable, almost do not wear out, and thanks to a smooth surface they are not able to accumulate scum. Also such pipes withstand negative temperatures, and at the same time are relatively inexpensive, which provided the material with the widest popularity among customers with completely different budgets. When choosing pipes it is worth to build on future operating conditions, stopping at those that are most suitable for a particular room. It is also worth noting that pipes, along with all the necessary, are better to buy from reliable manufacturers and in proven locations: a vivid example is the products presented by AquaLend at http://www.akvalend.ua/.
And now let us dwell on what polypropylene pipes are, and which ones are best suited to specific conditions.
Types of polypropylene pipes
Properties of pipes directly depend on the structure of the material:
- PPH (polypropylene homopolymer)- a solid material, the disadvantage of which is the inability to withstand low temperatures. That is why such pipes are most often used for the arrangement of industrial pipelines for cold water supply, or for the organization of ventilation ducts;
- RRB (block copolymer)- an excellent wear-resistant material, which contains up to 30% polyethylene. It gives the finished products the ability to withstand low temperatures, as well as the necessary flexibility. Thanks to all these advantages, these pipes are often used not only for cold water supply, but also for transportation of corrosive substances. In addition, this type of pipe is used in the arrangement of internal sewerage and underfloor heating. Shockproof pipes and fittings are also made of this material, which again confirms their excellent performance properties;
- PPR, PPRC (copolymer of propylene and ethylene).Such pipes have found wide distribution in the arrangement of the system of cold and hot water supply, heating, incl. and outdoor, but it should be noted that the temperature of the coolant should not exceed 70 ° C;
- PPs (special propylene)- this is the most popular material for today, which should be chosen to equip a reliable heating and heating system at home. Such pipes have incredible performance properties: they withstand high pressure, low temperatures, and The coolant in them can be fed at a temperature of up to 95 ° C, and one can be absolutely sure that the pipe material will not be.
What are reinforced pipes?
With all its meritspropylene pipes have one drawback- when the temperature rises, they are able to expand and lengthen. To level this feature, manufacturers have long been adept at reinforcing pipes. If you want to purchase the productfor arrangement of hot heat supply or heating, thenreinforcement becomes a prerequisite. It should also be taken into account that the reinforcing layer is made of different materials:
- aluminium foil, which is located in the walls of the pipe, gives the product the necessary strength, but at the same time complicates the installation;
- polyethylene layer, which is applied to the inner walls of the pipe. This type of pipe is actually a metal-plastic pipe, the outer layer of which is made of polypropylene. The main advantage of this solution is that the pipes can withstand a higher temperature, but not without a number of drawbacks. This again, some difficulties in the installation, as well as multi-layered products, which can not fail to affect the reliability and durability, because different layers are connected by glue;
- reinforcementfiberglassis considered the most reliable solution to date. Such products have a monolithic design, have high rigidity, almost do not change when exposed to high temperatures. In addition, during installation, such products are simpler, since it will not be necessary to perform a special cleaning before welding, as in the case of the two previous types of pipes.
The working pressure for which specific pipes are calculated is another important parameter that must be taken into account when selecting. It depends on what the pipes are for: hot or cold water, or, perhaps, a heating system.
So,on products there should be a corresponding marking: after the letters PN there is a number corresponding to the pressure of the liquid on which the specific pipes are designed. For example, PN10 pipes withstand pressure of 1 MPa, PN20 - 2 MPa, PN25 MPa, etc. Depending on a number of other characteristics of pipes with different operating pressures in each specific case, you need to choose the most suitable product:
- PN10 pipes- one of the cheapest options, they have a thin wall and can withstand temperatures up to 20 ° C, so they are recommended for use only in the cold water supply system;
- PN 16can withstand temperatures as low as 60 ° C, therefore they can be used both in cold and hot water supply;
- PN20 pipesperfectly tolerate the temperature up to 80 ° C, so they are excellent for hot water supply;
- PN25 pipeswith reinforcement used in the heating system, but can be applicable for water supply.
Diameter of pipes
The diameter of the pipes is another parameter that needs careful consideration. So, before designing a water supply or heating system, it is better to calculate which pipe diameter is needed. For large private houses or for apartment buildings, it is better to use a special calculation, and for A small house can take pipes with a diameter of 20 mm (for heating) or even 16 mm (for water supply). If the diameter of the pipe is more than necessary, there will be little harm from this, but it is difficult to name such a solution economically. If too small a section is chosen, then there will be problems with pressure.
The modern construction market presents pipes with a diameterfrom 16 mm up to 1200 mm, but such huge products are used more often in industry and production. For a domestic heating system, pipes with a diameter of 16-32 mm are quite suitable, for sewerage - from 40 to 110 mm. We are talking about the internal diameter of the pipes, since the outer one has absolutely nothing to do with it and can only indicate the thickness of the walls, which determines the rigidity of a particular product.
there isformula, allowing a rough calculationrequired diameter of polypropylene pipefor water supply, and it looks like this:
, where Qob is the peak water flow rate, v is the water velocity (-2 m / s for thick pipes and, m / s for thin ones).
When calculating it is better to use the maximum speed for a given type of pipe, since the smooth surface of polypropylene does not practically resist the movement of water.
Substituting specific values, you can deduce the value of the diameter of the pipes necessary for the organization of water supply in the house. More accurate hydraulic calculations will be needed for the organization of water supply for the apartment building, but there already exist their time-tested solutions:for five-story buildingspipes with a diameter of 25 mm are used, andfor nine-storey houses- 32 mm pipes. Pipes of a larger diameter are used to supply water to apartment buildings, but for heating mains polypropylene is not applicable, since often the temperature of the water is so high that even reinforced reliable products can not cope with such a impact.
Naturally, betterdo not take pipes with a diameter less than the required, otherwise there is a risk during peak hours to stay with a bad pressure of water or without it at all. But, on the other hand, there is a temptation to take a pipe with a diameter much more than necessary, because in this case it is unnecessary to count anything, check, etc. Such a reckless decision will not only require more money to buy products, but in the future it will not allow save.
To know the inside diameter of a polypropylene tube, if it is not indicated on the packaging, you can use the ratio of the outer and inner diameters. Thus, with an external diameter of 16 mm, the inner diameter will be 10 mm, at 20 mm - 15, at 63 mm - 50, at 125 mm - 100, etc.
When organizing a heating system or a water supply for an apartment or a small house, accurate calculations are not needed in most cases, since there are not so many water intake points. The most commonly used pipes are 20 mm for heating and 16 mm for the organization of water supply.