To create a heating circuit, polypropylene or metal-plastic are often considered. Both materials are similar, because the basis of the composition is an organic polymer. But metal-plastic products have an insert made of foil or fiberglass, due to which they can withstand higher temperatures. A description of the advantages and disadvantages of both materials, as well as a detailed comparison of the main characteristics can be found in this article.
The content of the article
- Similarities and differences of materials
What is better for heating: comparison by parameters
- Mounting method
- Number of connections
- Section on fittings
Similarities and differences of materials
Considering which is better - polypropylene or plastic, first of all you need to understand how exactly they differ. Both pipes are made of the organic polymer of the same name - polypropylene. The result is white products made of dense plastic, which are lightweight and have several advantages:
- absolute resistance to corrosion;
- resistance to pollution due to smooth inner walls;
- light weight and easy installation - using a soldering iron, you can quickly build a pipeline of the desired length;
- affordable price;
- convenient transportation.
But if you study in detail which is better - polypropylene or plastic, you can find several drawbacks of the material:
- withstands temperatures only up to 70-80 degrees;
- expands significantly when heated, which can lead to deformation;
- is destroyed by prolonged exposure to open sunlight.
Metal-plastic is made of the same polypropylene, but in the middle it has a layer of aluminum foil or fiberglass. Due to this, such pipes are more resistant to heat (withstand up to 90-100 degrees) and expand less under the influence of high temperature. Therefore, it is quite obvious what is better for heating - polypropylene or metal-plastic.
However, polypropylene pipes have their advantages. They are more affordable, so they are in great demand. Such products are great for hot and cold water supply systems, where the circuit temperature is just within the acceptable range (60-70 degrees). They can also be used to create an inexpensive country water supply.
What is better for heating: comparison by parameters
The pros and cons of polypropylene pipes, as well as the composition of the metal-plastic allow us to conclude which products are best suited for heating. To deal with this issue in detail, it is necessary to make a comparison according to the main technical characteristics.
If we talk about which pipes are better - metal-plastic or polypropylene, you can start with the most important parameter - durability. This indicator primarily depends on the resistance to high temperatures in the heating circuit.
On the one hand, metal-plastic will last longer due to a layer of aluminum foil or fiberglass. But on the other hand, it also has temperature limits of 90-100 degrees. However, in the heating system, the indicator can reach 110 degrees, which is equally harmful for both metal-plastic and classic polypropylene.
With constant exposure to high temperature, the material expands greatly and deforms over time. Therefore, the service life is reduced from the one declared by the manufacturer (50 years) by almost half - up to 20-25 years. This problem is especially relevant for apartments where there is no way to adjust the temperature.
To figure out which is better - metal-plastic or cross-linked polyethylene, you also need to evaluate the installation method:
- Polypropylene products are heated on a soldering iron and connected together. Moreover, you need to hold them for a strictly defined number of seconds in order to prevent overheating and at the same time provide the desired melting temperature. Also, the fragments are connected with fittings and adapters, which is somewhat more difficult compared to metal-plastic.
- metal-plastic pipes are mounted only with fittings, a soldering iron is not used in this case. On the one hand, it is easier, but on the other hand, you need skills in working with press tongs. Instead, you can connect the elements with collets, but then you will need to periodically tighten them.
Number of connections
The difference between polypropylene pipes and metal-plastic pipes is also connected with the number of connections during the installation process. The fundamental difference is that polypropylene is supplied in small fragments up to 2 m, and metal-plastic - in bays of several meters.
Such products can be bent at small angles, use a spring or lever-type pipe bender. It turns out that the number of connections is much less for a metal-plastic circuit, which also facilitates installation.
Section on fittings
But metal-plastic also has a significant drawback - a significant narrowing in metal fittings. For example, a pipe might be 3/4 inch in diameter, but an elbow diameter is only 1/2. Therefore, in the event of an emergency, pressure drop, it is these connections that are most vulnerable.
In the case of polypropylene, this drawback is absent, since the diameters of the pipe itself and the fitting exactly match each other. Thus, metal-plastic wins almost on all counts, except for the last one. But even despite this, it is he who is more often used in the heating system than classic polypropylene.