Plastic gas pipe: types of pipes, rules of use
Plastic gas pipe is a relatively new type of equipment. It is increasingly used to supply and transport fuel on the site of a private house or in commercial buildings. This equipment has many advantages, however, before applying it on your site, it is necessary to get acquainted with certain features of a product and the installation instruction.
Plastic gas pipes have many advantages over metal, but they are allowed to be laid only underground
Quality gas pipeline for a private house: what it consists of
Gasification in a private cottage is a complex and time-consuming process. It requires maximum accuracy, accuracy and professionalism. If it was necessary to build or repair gas communications, it is better to seek the help of specialists. It is very important to follow all precautions and monitor, that the design and its installation / repair meet all fire safety requirements.
The scheme of gasification in the house includes the following elements:
- gasholder - a special tank for gas storage;
- fuel supply pipes;
- gas boiler, boiler, gas stove, fireplace or other appliances.
When installing this system, it is important to choose the right gas pipes. It depends, what are the working volumes of the gas pipeline you are counting on, what type, soil condition and corrosion activity at the site, as well as that, what amount do you expect.
Wrinkle! It is better to use the services of specialists, to determine, from which material the elements of gas pipelines should be made - metal or plastic. To do this, there are certain requirements for gasification and state standards.
Gas supply to the house must be carried out in compliance with safety measures, and the choice of pipes plays an important role here
Advantages of plastic
Recently, communication equipment for plastic gas has become very popular. The material itself was invented relatively recently, and in the field of construction and repair work began to use it even later. However, it is now in demand, since it has advantages, compared with metal counterparts.
Firstly, pipes, made of it, not prone to corrosion, which is the main weakness of iron products. Plastic pipes for the gas pipeline do not require additional protection and insulation, which is why, non-conducting, are resistant to the negative effects of the environment, various kinds of organic and chemically aggressive substances. in addition, they do not require cathodic protection.
Secondly, plastic gas pipe operates successfully even with frequent changes in temperature, but not in extreme conditions.
in addition, such a pipe is very durable and strong, provided by a homogeneous structure and performance characteristics of the material itself. The warranty period expires 50 years.
Plastic gas pipes are convenient and easy to install, they are easy to transport to the work site
Another plus - versatility. Due to the plasticity, pipes can be used in the construction of gas pipelines of the most complex device and in the most inaccessible places, adverse natural conditions.
Features in comparison with steel analogues
In addition to the advantages, any product has certain disadvantages, and plastic pipes for the pipeline are no exception. Before, how to install them, take into account, that installation of such designs is impossible:
- Ground and above ground. Plastic gas pipes are designed for underground communications, located inside the soil.
- In areas of high seismic activity. This applies to territories, where the activity level reaches the mark in 6 points.
- Within the city in areas of high gas pressure (in gas pipelines 1 and 2 categories).
- Indoors, residential, commercial and industrial buildings, collectors. It is customary to use mainly steel structures.
- Plastic pipe for gas is inferior to metal in strength characteristics.
If you compare plastic pipes for gas pipelines and steel communications, then you can notice some significant differences:
- Cost. Because steel pipes require additional electrical insulation and protective layers, then more time and money are spent on installation and maintenance. And steel prices are a little higher, than on plastic products.
- Weight and transportation. Steel equipment weighs much more, which complicates its transportation. in addition, polyethylene products are transported in bays, which makes them more compact.
- Versatility. If with a plastic pipe for gas in a private house, everything is simple, then steel products must be used strictly taking into account the temperature, landscape conditions, operational parameters. Depending on it the necessary thickness is selected, design features.
- Installation. The steel pipeline is a bit more difficult to install, than plastic.
Despite all the advantages of plastic gas pipes, it is forbidden to use them in high-pressure gas pipelines
When choosing the right material, be sure to consider the above differences and features.
Types of plastic pipes
Depending on the material, plastic pipes come in different types. Each variety has its own characteristics and specifics, which must be taken into account when laying communications.
The first type - low and high pressure polyethylene pipes. There are two brands of such pipes, visually different colored stripe. Gas is marked in yellow. This type of equipment has a democratic price, light weight, elasticity. This option is suitable for the installation of communication systems for cold water supply, as well as sewers.
The second type - polyvinyl chloride pipes. This is a more stable design, but its use in plumbing systems is not recommended, as at interaction with separate substances it allocates toxin chloroethylene. But for the sewer, they are quite suitable as a replacement for cast iron pipes.
A safer option is polypropylene. It is practically inactive when interacting with chemicals. This gives it an advantage, that is available in metal-polymer pipes - versatility. That is, it can be used in various types of communication systems, including for gas supply.
The most common type of gas pipes made of polymers are low-pressure polyethylene products
Pros and cons when comparing metal-plastic and polyethylene pipes
It is equally easy to transport plastic or small diameter polyethylene pipes. They are available in bays 50-500 m and weigh in 2-4 times less than steel counterparts.
Butt welding of gas plastic pipes is also cheaper, than in the case of steel. This does not require additional consumables. And the process itself is much easier and faster. You can use thermistor couplings, which also simplifies the installation procedure. Such a pipeline can be laid by drawing. And he will serve for a long time, without requiring frequent intervention and repair also thanks to a smooth and elastic internal surface. Thick-walled polyethylene pipes can be used for gas pipelines of the third and sometimes even the second category.
But, there are some differences between these types of material:
- at extremely low temperatures polyethylene gas pipes lose their operational capabilities and possible breakage;
- PVC pipe is stronger and safer in terms of reaction with chemicals;
- polyethylene is not resistant to the negative effects of ultraviolet rays, so you need to install a plastic pipe for underground gas, and not in the open or in a lighted room. Otherwise, it may reduce the share of the service and the negative consequences. But for PVC pipes this restriction is not relevant;
- it is possible to lay polyethylene pipes outdoors only in the ground, to protect the equipment from mechanical damage, while metal-plastic pipe has greater strength.
Metal-plastic pipe has greater strength, than PON, and it can be used there, where there is no possibility to make a hidden laying of the pipeline
What to consider when installing
First, than to start work, make sure, whether you can use plastic gas pipes in your area. To do this, you should pay attention to some points.
The gas pipeline from polymeric pipes can be laid only by the hidden method. Polyvinyl chloride has a low percentage of expansion, so feel free to install pipes in concrete or specially equipped galleries. However, not very tight, preferably with an insulating soft material, so as not to damage the pipe.
Wrinkle! Remember, what, the less fittings used, various connecting and butt elements, accessories, the more stable the pressure. And that means, decreasing and energy costs for fuel transportation.
Use pressed or crimp fittings to connect the pipes. Make a diagram in advance, on which the plastic gas pipeline route will be built. Take care of that, that it be approved by the appropriate authorities. It is better not to try to do the work yourself, and seek professional help. Remember, that gas supply and transportation equipment is a dangerous thing and improper installation or maintenance can have tragic consequences for you and your loved ones.
Ways to connect elements of communication systems
The plastic pipe should be mounted underground or in another environment (hidden method). Connect the pipes, mainly, by welding.
Welding of plastic pipes is carried out using a special welding machine, its type depends on the chosen welding method
There are three main ways to weld:
- Electric coupling. Plastic gas pipe melts under the influence of current and is connected to another by means of a fitting. This technique is used for polypropylene and polyethylene gas communications.
- Butt. This connects all types of plastic pipes with a diameter of 5 to 16 millimeters.
- Vroztrub. This is a type of welding, designed, mainly, for repair and installation of sewer and water supply systems. They are connected by pipes with a diameter of 15 to 90 millimeters.
As for plastic pipes for gas in a private house made of polyvinyl chloride, then they are connected with glue. You should not be skeptical about this type of attachment, as modern technologies allow to make strong glue, which provides a strong connection for several decades. This method is more convenient and does not require special equipment, providing special conditions for the adhesion process.
How to properly weld pipes
To properly and securely connect the elements of gas communications, strictly follow the instructions, on which the plastic pipe is welded butt. This method allows you to connect system elements quickly. Thanks to it even the big pipe in diameter from can be processed without special difficulties 50 to 120 millimeters.
To do this, you will need a special welding machine. There are different types of such equipment:
- with hydraulic drive;
- with electric drive;
- on software management.
Which one to choose, depends on that, what amount do you expect, what working conditions and provided matter, of course, scope of work.
If you have purchased the necessary equipment, you can start work directly.
- first install the ends of the parts in the welding machine. Watch out, that the fixation was good and smooth;
- then place the heating element between the ends of the pipes. Wait for the formation of the first lattice - that is, when the polyethylene begins to melt;
- remove the hot plate and press the ends together with the necessary effort. Give time after the process, to cool the pipe.
Wrinkle! Do not try to cool the plastic pipe by force, using water. The temperature should drop to ambient level naturally.
Plastic gas pipes are a modern material, which has a lot of advantages. But gas mains have their own specifics, therefore, these pipes are not allowed to be used on all sections of the gas pipeline. Therefore, you should consult with experts first, than to decide on the construction or upgrade of the system.
