Today, during the construction of buildings Special attention is devoted to water supply and gasification systems. They simply must be reliable and provide a high-quality, leak-free supply of water or gas to the end consumer.
For this, various pipeline fittings are used, but it is also equally important to ensure high-quality connections of household appliances and various plumbing equipment on site to gas and water communications. For this purpose, flexible eyeliner has been successfully used for many years. What is a flexible gas line, what is a bellows line, and what types does it come in? Let's try to figure this out.
Flexible eyeliner- this is a kind of hose with fittings or other elements at the ends for connection to pipeline systems and plumbing itself or household appliances. Using flexible hoses, as already noted, household appliances (washing and dishwashers, plumbing fixtures, faucets, gas stoves) to gas and water supply systems. In this case, not only the necessary working medium (water or gas) is supplied, but also the mobility of household appliances is ensured - it is possible to move them in such a way that it is most convenient to use them, there is no connection to the risers. In addition, the installation process itself is quite simple, convenient and fast, so that problems almost never arise during installation, provided, of course, that a specialist is involved in this - after all, as you know, a gas leak or a water pipe break are serious things that lead to sometimes to irreparable consequences. 
All types of flexible connections are divided depending on the type of working medium supplied into water connections and gas connections. However, their differences lie in the materials used to make the eyeliner. The connection for the mixer can be made of ordinary rubber, for example, with aluminum or stainless braid, but for gas connections, other materials are used - special polymer hoses without aluminum in the braid. Also, water and gas connections may differ in the way the “hose” itself is attached to the end fittings - fittings, nuts, fittings: a flexible water connection is usually connected by rolling, and a gas connection is usually connected by argon-arc welding. But in any case, there may be other connection options that are not tied to the purpose of the flexible liner. However, the main classification of flexible hoses is based on the type of construction, namely rubber hoses (or sleeves) and bellows hoses. Let us next consider in more detail the design features of each type of flexible liner.
Rubber sleeves
This type of flexible hose is a rubber (rubber) or polymer hose, which, to protect against external influences, is braided quite tightly with metal wires or threads, while stainless steel or aluminum is often used as the braiding material. At both ends of this type of flexible hose, metal bushings or fittings are installed, which in turn are crimped with a metal nut. The tightness and reliability of the rubber flexible hose depends on the quality of the connection between the braided rubber hose and the metal bushings. Therefore, it is necessary to purchase rubber hoses only from well-known, time-tested manufacturers. Note that this gas supply is different low price, accessible to almost all consumers, but at the same time it is significantly inferior in strength and operational characteristics another type of flexible liner - bellows. On the contrary, with regard to the use of water supply in public utilities, flexible water supply with metal braid is currently the most widely used, fully meeting all standards for the operation of plumbing. 
Bellows eyeliner
A flexible bellows-type hose, in principle, is a metal sleeve made in the form of a corrugation with folds - a bellows metal hose, which allows you to bend and compress the hose without any problems. Bellows liners, unlike their rubber “brother”, wear out much less, are more reliable, resistant to mechanical stress and effectively protect against breakdowns Appliances which it connects to the pipeline. Thus, the flexible bellows connection also increases the safety of using household appliances connected to water and gas systems. Naturally, the cost of flexible bellows-type hoses is significantly higher than the price of braided rubber hoses. But you must agree that the advantages described above that bellows eyeliner provides are worth the money. Flexible bellows hoses are becoming increasingly popular and are gradually replacing rubber hoses. For example, the number of sales of bellows gas connections wholesale and retail in Moscow has already significantly exceeded similar figures for rubber hoses in metal braid. Flexible bellows-type gas supply is rapidly conquering the plumbing market.
At the same time, we should not forget that with the growing popularity of bellows eyeliner, the number of low-quality, counterfeit products is also growing. Therefore, as in any other case, when choosing flexible eyeliner, you should pay attention to the reputation of the company producing these products and, of course, purchase flexible eyeliner only from well-known and trusted suppliers, regardless of whether you want to buy flexible eyeliner wholesale or retail. Attention! The use of counterfeit, falsified and low-quality products can lead to tragic consequences. Don't put yourself and the people around you at risk.
The Armagaz group of companies offers to your attention flexible gas connections from the following manufacturers:
Gas lines of a fixed length (for example, 1.0m, 1.5m, etc.) are most widespread in our country. Fixed eyeliner has more low price, since the manufacture of a metal spiral sleeve for it, compared to a stretchable liner, requires less metal (see the drawing below in the text and the drawing on the page dedicated to the compressed bellows liner). Most commonly used gas connection with connecting dimensions 1/2" (connection for a gas stove), which also serves to connect cylinders, ovens, water heaters and some models of gas boilers.
More recently, on Russian market A flexible gas connection, made of a rubber tube in a metal braid, predominated. By the way, for example, in Europe, which cares about the safety of its citizens, such products, even before the start of their expansion into the territory of the former Soviet Union, have already been banned from use.
This is not surprising, since such a product, even produced by well-known companies, is flexible gas supply, had many disadvantages due to its design:
Firstly, this is the tube itself, which is an NBR elastomer. We all remember from our school physics course that gas is an aggregate state of a substance in which intermolecular bonds are free and the molecules are very mobile. And these very mobile molecules tirelessly bombard the unfortunate rubber tube. Naturally, it won't last long.
Secondly, it is a metal braid. Stray currents passing through it can heat up thin (0.20 mm) braided threads. The effect is like the filament in Ilyich's light bulb - pure Ohm's law.
Good, the attentive reader will think. It’s clear with the tube, the bellows connection for gas simply does not have it. What about stray currents? Of course, a solid metal hose is unlikely to get as hot as a thread with a cross-section of 0.20 mm. But still, metal is an excellent conductor of current. The answer is simple - when installing a metal spiral liner, use a dielectric insert.
Annealed gas liner: Even better for the same money
Gas connection Lux: Highest level of safety
In civilized countries, safety requirements for gas supply equipment are constantly becoming more stringent. And this is justified, since gas does not forgive careless handling.
We are pleased to offer our customers a product that complies with the most modern European safety standards EN 14800:2007 and is supplied to countries Western Europe. This gas connection has a number of design features, which serve as guarantees of reliability and durability:
Fittings (nuts, fittings) are made not of carbon steel (so-called carbon steel), but of of stainless steel AISI 303. This prevents rusting of fittings when used in rooms with high humidity.
- Along its entire length, the bellows metal hose has an external stainless steel braid, which acts as a reinforcing frame.
-The bellows in a metal braid is placed in a protective shell that is resistant to heat. The shell expands the range of operating temperatures - this is especially important when connecting built-in gas equipment ( hobs, ovens), since in built-in kitchens the hose is located in closed spaces with poor air circulation. The ambient temperature in such places can exceed 100 degrees Celsius, which is already higher than normal operating temperature for hoses without sheath.
Operating temperature: -20.....+140 degrees Celsius (shell heating temperature up to 120 degrees).
- The protective sheath is rigidly fixed to the hose with compression sleeves.
And finally one more interest Ask, asked by our clients, and people who intend to purchase corrugated eyeliner at retail are more concerned about this question:
"What is the maximum permitted length gas line?
Please give us the link to normative document regulating this issue!" In Europe, according to European standards UNI-EN, it is 2 meters. What about us?
We quote paragraph 7.3 verbatim. Building codes and rules SNiP 42-01-2002 “Gas distribution systems” (as amended on March 1, 2005), approved by Resolution of the State Construction Committee of Russia No. 163 dated December 23, 2002 and which came into force on July 1, 2003:
“Internal gas pipelines should be made of metal pipes. Connection to them of household gas appliances, instrumentation, LPG cylinders, gas burners of portable and mobile gas-using equipment may be provided with flexible hoses that are resistant to the transported gas at a given pressure and temperature.” That's all. No word on the maximum allowed length. The main thing is that the liner be “resistant to the transported gas at a given pressure and temperature.” Those wishing to read the full text of this normative act can download it from the Documents section of our website.
Gas connection 1/2": BUY!
Gas connection 3/4":
Modern a private house, and especially an apartment in apartment building, it is impossible to imagine without gas equipment. This could be a stove, a heating boiler, a heating boiler, or other household appliances.
Gas is supplied to a house or apartment through a pipeline system, and from it to each individual consumer via flexible connections. Flexible gas supply can be made in several versions at once.
Varieties
Flexible gas supply can be represented by three different types in terms of quality, price and material of manufacture. The division into types is carried out according to the material of manufacture. So, the sleeve can be:
- Rubber, that is, made of rubber, additionally reinforced with thread;
- Made of steel - rubber, which has a metal braid, usually made of stainless steel;
- Bellows.
Description of rubber products
The rubber tube is made of rubber, which is completely reinforced with nylon thread. Hoses are usually sold with lengths from 1.2 to 4.
Advice! In this matter, it is better to choose the shortest one, as it will be more durable and reliable. Therefore, if, for example, a gas stove requires a hose 1.3 meters long, then it is better to move the stove a little and purchase 1.2 meters rather than 1.5.
Generally speaking, rubber fabric eyeliners are the softest of all three presented. This quality can be called a disadvantage, since there is no safety margin.
The technical specifications are as follows:
- Manufactured according to the requirements of TU 23.05765871.01-92 (of course, this is for those materials that are domestic);
- Capable of withstanding pressure up to 0.05 MPa;
- Retains its properties and works normally in the temperature range from -10 to +70 degrees Celsius. It should be noted here that this is the temperature range that does not have any effect on the rubber at all. Rubber liners can work normally even at -50, but at this temperature the rubber becomes less flexible and can easily tear, or rather crack;
- Has connection dimensions G1/2”.
As for installation and maintenance, there is nothing complicated, there are only a few recommendations:
- The hose should not be in the fan blowing area (with hot air), in direct contact with gas appliances(of course, except for the connection point) and also near the oven;
- The tightness of the connection is achieved using special paronite gaskets;
- During use, the sleeve should not be stretched or bent at very sharp angles;
- The service life ranges from 7 to 10 years depending on operating conditions.
Stainless steel
Flexible gas lines made of steel are very common today. It is represented by a tube that has a stainless steel braid. The braid has a yellow stripe. By appearance Such tubes are very reminiscent of water products, which instead of a yellow stripe have red and blue.
At the ends of the hose there are two fittings, which, like the braid, are made of stainless steel. The fittings are inserted into the mounting points and secured with special union nuts. In this case, the tightness of the connection is achieved using special washers made of soft metals such as copper and aluminum.
Conditions of normal operation are those under which normal temperature regime(the same as for rubber products), there are no kinks or breaks in the hose, it has no tension.
One of the advantages of such a stainless steel liner is that it is very cheap, while being much stronger and more rigid in relation to rubber-fabric products.
Bellows liner
One of the most expensive and most reliable eyeliners. Made in the form of corrugated metal pipe. There are two fittings at the ends, which are secured using union nuts and sealing washers.
Capable of withstanding pressure up to 6 atmospheric units, while the normal pressure in the gas supply system is considered to be 0.03 atmospheres.
The operating temperature range is from -50 to +250 degrees. Since the bellows is, in fact, corrugated, it is not afraid of stretching. In addition, the bellows hose is capable of stretching up to 3.5 times. A normal stretch is considered to be an increase of 50-70 percent.
The bellows liner has a bright yellow color, and the union nuts and fittings have the natural color of stainless steel.
As for the scope of application, there is only one - connecting the consumer to the gas supply system.
Installation is carried out through a special insert - dielectric. Its purpose is to prevent the spread electric current along the hose if a breakdown occurs. This insert is mounted between the consumer and the hose.
Tsugunov Anton Valerievich
Reading time: 6 minutes
Not so long ago, owners didn’t even have a question about which hose to choose for a gas stove. In Soviet times, these household appliances were tightly connected steel pipes to the gas pipeline. It was simple, reliable, safe, but inconvenient: the slab could not be moved even a millimeter after installation. With the advent of a new product, it became possible to connect the stove using flexible hose, so that the device can be rearranged or temporarily moved if necessary.
Expert opinion
Tsugunov Anton Valerievich
Hello, friends!
Never use gas hoses without the appropriate markings, permission from Rostekhnadzor of Russia for their use, as well as certificates of compliance with SNIP and GOST. It is mandatory to have a flexible hose passport, which indicates the date of manufacture, service life and replacement of the hose.
It is advisable to inquire in advance with the gas company in your city about technical conditions requirements for methods of connecting gas stoves. This may refer to the maximum length of the liner, the way it is attached and the materials from which it should be made.
Requirements for gas hoses
- Flexible liner is a complete product; any connections (couplings, extensions) are unacceptable. You cannot make one out of two hoses.
- The hose must be resistant to oils and not subject to corrosion.
- The hose must match the parameters of the gas used.
- Access to the flexible line must be provided (it cannot be placed in boxes, grooves, etc.).
- Hoses with a service life of at least 10 years should be used.
The maximum permissible length of the connection is indicated by the gas stove manufacturer. For example, the European standard: EN14800:2003 – two meters. The maximum length of a certified gas hose is 7 meters.
There are no direct instructions on sizes in GOST!
How long are gas hoses?
The most common eyeliner sizes are as follows (in centimeters):
Types of hoses
Today, several types of hoses are used to connect a gas stove:
- oxygen;
- rubber-fabric;
- reinforced rubber;
- rubber with metal braid;
- reinforced with PVC;
- bellows.
It is worth considering them in more detail before choosing the right one.
Oxygen
Oxygen hoses were often used in Soviet times, since there were simply no other options for connecting via flexible hoses. Now this product fades into the background. Cost - from 60 rubles per linear meter without tips.
Positive traits:
- ability to withstand high pressure(up to 20 atmospheres);
- ease of installation;
- cheapness;
- does not conduct electricity;
- can be selected to suit any pipe diameter.
For the rest - a good option for having its advantages:
- high level of electrical insulation;
- wide range (easy to find for any pipes);
- Thanks to its softness, it can be easily trimmed to suit existing conditions.
You can install the product yourself, but it is better to contact a specialist.
With metal braid
It has an optimal ratio of price, quality and durability. Price from 140 rubles per 60 cm of finished product. The hose is made of vulcanized rubber and reinforced textile thread. The outer part is a metal braid.
The gas hose is similar to the water supply (for the toilet, taps, shower). You can distinguish it by markings: plumbing products have blue and red marks for cold and hot water, a yellow thread is woven into the gas braid.
One of the most common options, the popularity of which is associated with many positive qualities, among which:
- high level of reliability;
- ease of installation;
- longer service life compared to rubber products;
- large selection of lengths and diameters;
- permissible temperature has a wide range from -35 to + 50 degrees;
- ease of use.
It is prohibited to use the product without installing a dielectric insert!
Expert opinion
Tsugunov Anton Valerievich
An all-rounder, I have been renovating and finishing premises since 2003, with more than 100 completed projects. I value quality more than quantity!
Gas services often recommend replacing old metal-braided hoses due to the inability to check the condition of the rubber under the braid. If it is impossible to confirm the relevance of the product’s service life by the passport, then I recommend replacing the eyeliner with a bellows or reinforced PVC one.
PVC reinforced
PVC gas line is one of the latest developments. It does not conduct electricity, does not break down like rubber, and is almost as durable as a bellows hose. It has 2 layers: an inner one made of black PVC, and an outer shell made of yellow PVC. Due to their novelty, not all gas services accept them for operation, so it is better to consult an authorized organization in advance. Price for 60 cm of product - from 140 rubles.
Properties reinforced PVC hoses:
- flame retardant;
- dielectric;
- withstands hot plate contact test;
- quite cheap with a comparable service life;
- resistant to oil mist;
- operated under conditions of increased loads;
- meets the requirements of GOST R 52209-2004, GOST12.2.063-81, GOST12.2.003-91;
- guaranteed service life - 12 years, actual service life - more than 20 years;
- length from 60 cm to 5 m.
The bellows hose is made of stainless steel, with a PVC coating on top. This ensures it will last for a long time: average term operation life is 25–30 years. The metal braid reliably protects against mechanical influences, and the PVC coating provides electrical insulation and chemical resistance. Thanks to the corrugated surface, the product bends easily.
Bellows gas hose has the following advantages:
- can be connected to any gas equipment: stoves, boilers, etc.;
- has connecting dimensions 1/2″, 3/4″, 1″;
- has excellent flexibility;
- withstands pressure up to 6 atmospheres;
- wide range of operating temperatures: from -50 to +250 degrees (installation outdoors is allowed; nothing will happen to it if it comes into contact with hot surfaces);
- able to withstand mechanical loads and aggressive influences environment, household chemicals;
- hoses comply with the requirements of GOST R 52209-2004, GOST12.2.063-81, GOST12.2.003-91;
- warranty service life - up to 15 years;
- service life – up to 30 years;
- is able to ensure the tightness of the system even under extreme loads, for example, during an earthquake.
The length of the bellows gas hose varies depending on the manufacturer.
With Emiflex, the eyeliner can double in size and has following parameters(in meters):
- from 0.26 to 0.52;
- from 0.5 to 1.0;
- from 0.75 to 1.5;
- from 1.0 to 2.0.
And Eliteline hoses have a fixed length (in meters):
The only thing that can scare off a buyer is the price. But considering its durability, it is the most profitable purchase.
Do not use the hose without installing a dielectric insert!
Rules for choosing a gas hose
Some simple tips will help you choose a gas hose, save time and money and avoid troubles with energy leakage:
- Buy any products only in specialized stores, and do not forget to ask the seller for a quality certificate.
- You cannot buy Chinese hoses: they are thin and quickly become unusable. There are also many fakes.
- The slabs are connected only with those sleeves that have a special yellow mark. They cannot be replaced with plumbing ones. The latter are not designed for such loads and wear out in a few weeks.
- When purchasing, the eyeliner must be carefully inspected for damage.
- Select the size so that the product sags and does not stretch.
- Pay attention to the mounting methods - fitting or nut - select them according to size.
- The hose must be laid in an easily accessible place. It is not safe to hide it in a wall or under the floor.
- The bending radius should not be less than three times its diameter.
- The product must not be pulled, twisted, bent, or painted.
- Metal parts must be protected from condensation, which leads to oxidation of the material.
- You cannot connect steel elements (tips) with copper ones, this can lead to electrolytic damage to the product. Acceptable combinations are steel with steel, brass with copper.
- All connections must be tightened tightly, but without excessive force, so as not to damage the threads.
- A dielectric insert is installed between the tap and the gas hose, which prevents the accumulation of stray currents, which can lead to overheating of the braid, damage to the device, and melting of the rubber.
- rubber hoses (with and without sheath) – 5-year warranty, service life up to 10 years;
- PVC eyeliner – 12-year warranty, lasts up to 20 years;
- bellows gas hose - 15 year warranty, does not require replacement up to 30 years.
When installing the hose, use the following recommendations:
Gas line service life
After installing the hose, you should check its service life and remember the installation date. The product, depending on the type, is designed for a period of 5 to 15 years. It is important not to forget to replace it on time.
Guaranteed service life is indicated in the product passport and in the certificate of conformity.
Which gas hose is best?
- By ratio technical characteristics The leader in cost and cost is the bellows gas hose; it’s not for nothing that gas workers themselves recommend it. Don't forget to install the dielectric insert with this product!
- Next comes a PVC gas hose, it is less durable, but does not require electrical protection and is not destroyed by oil. Which gas stove hose did you choose?
All gas equipment in the house, including gas heating boilers and gas stoves, are equipped with special fuel supply hoses. As a rule, such hoses are bright yellow.
Working with them yourself is prohibited. Such events should be carried out by special services. But the choice and purchase of this element often lies with the end consumer, so it would not be superfluous to consider what a bellows liner for gas is.
Types of gas hoses
If we consider everything, we can divide them into three large types, which differ from each other in the material of their manufacture:
- Rubber-fabric elements;
- Rubber sleeve with metal braid;
- Bellows liners.
Rubber-fabric sleeves are the softest of all three. Perhaps this quality can be called negative side, since mechanical rigidity is at the lowest level. Big advantage It can be said that rubber products do not conduct electricity.
The most popular today is a rubber hose with a metal braid. The reason for its prevalence and popularity is simple – low cost. A gas hose of this type differs from the same hoses, but for water, only in that there is a yellow stripe on its surface, which can be seen in the photo above.
And this type of water hoses have red and blue stripes. Such an element is shown in the photo below:
The bellows gas connection is the most reliable and rigid of all three types. Moreover, such a sleeve has the highest cost. All regulatory documentation recommends this type of hose. This is due to the fact that such a flexible liner perfectly withstands the high pressure created by the gas flow. A flexible bellows-type liner will be shown in the image below.
Advice! Regardless of what type of flexible liner is chosen, its diameter must be greater than 10 mm. This is due to the fact that modern gas equipment is quite powerful, and therefore requires large amounts of fuel to operate at 100%.
About bellows liner
So, briefly about what a bellows eyeliner is was described above. However, this issue should be discussed in a little more detail, since today this type of hose is becoming the most common, despite its high cost.
So, the bellows is a metal corrugated hose, which is made of stainless steel. At the ends of the product there are two fittings, which are also made of stainless steel.
This flexible line is attached to gas equipment or gas inlet pipe using special union nuts. In this case, a metal gasket must be used (only soft metal is used, that is, copper or aluminum). Special plastic can also be used as a gasket material.
The hose is made of stainless steel with AISI 316 coding. The fittings are made of more durable steel with AISI 304 or AISI 303 coding.
It must be said that some manufacturers from China and Turkey make fittings from carbon steel.
Advice! The best option will be the one where both the fittings and the corrugation are made of the same material. This is due to the fact that welding different materials leads to an electrochemical reaction that destroys weld. Such a connection will not be strong.
Particular attention should be paid to those pipes in which the fittings are simply soldered with tin or silver to the corrugation. They, like those in which the fittings are simply glued, will not be strong and durable.
As already mentioned, high-quality flexible liner of this type is the most reliable and durable of all existing ones. However, its price is significantly higher. It ranges from two times to 3.5 times the increase compared to a conventional rubber hose with a metal braid.
Some technical characteristics
Like any other material, this one has its own characteristics, which can be called its parameters, that is, performance indicators:
- So, the bellows hose is able to function normally without losing its qualities in the temperature range from -50 to +250 degrees Celsius;
- This material can withstand pressure up to 6 atmospheres. For common man this figure does not say anything, but if you compare it with the figure indicated in regulatory documentation, then the appropriate conclusions can be drawn. So, according to SNIP, the pressure in the gas supply system should not exceed 0.03 atmospheres - so compare these two indicators!
- Elongation can reach 100%. This means that a bellows that has undergone the annealing procedure can be stretched, up to twice its size. However, this is not recommended, since the rigidity is significantly reduced. The maximum elongation should not exceed 50 percent.
Scope of application and connection diagrams
The flexible hose has only one area of application - connecting stationary and mobile gas equipment to the gas supply system.
The service life of a standard hose is approximately 15 years. When installing it, it is recommended to use special gaskets called dielectric inserts. They prevent the flow of electric current and reduce the likelihood of breakdown. An example of such a dielectric insert is shown in the image:
Thus, the connection diagram will look like this:
- Gas supply system pipe;
