Dielectric insert for gas how to install correctly. Why do I need a dielectric coupling for gas and how to install it? How does a breakdown occur in the gas network
Goods ordered in the OBI online store are delivered in Moscow and the Moscow Region within 50 km from the Moscow Ring Road. Shipping costs are automatically calculated when placing an online order, based on the weight of the goods and the delivery area.
Minimum order amount for free shipping:
We will deliver your order for free if the delivery address is located in the first delivery zone for online orders, as well as:
- > RUB 5,000.00- for orders weighing up to 5.0 kg
- > RUB 10,000.00- for orders weighing up to 30.0 kg
The courier service delivers small-sized orders (weighing up to 30 kg) to the buyer's door, large-sized orders to the entrance (gate, gate) of the house. Delivery includes free unloading of goods from the car and their transfer within 10 m.
Delivery date and time
Next day delivery is available if you place an order before 18:00. You will be offered a choice of one of two 7-hour delivery intervals:
- - from 10:00 to 16:00
- - from 15:00 to 22:00
If you want to shorten the waiting period, you can choose one of the 3-hour delivery intervals for an additional fee:
- - from 10:00 to 13:00 +350.00 ₽.
- - from 13:00 to 16:00 +300.00 ₽.
- - from 16:00 to 19:00 +300.00 ₽.
- - from 19:00 to 22:00 +350.00 ₽.
Transferring the date and changing the time interval of delivery is possible no later than 24 hours before the previously agreed date and time.
More information about the terms of the courier service can be found in the section
Dielectric insert(or - one-piece connection that prevents the spread of leakage currents. The dielectric insert also protects the electronic components (for example, control units) and electrical circuits (for example, the electric ignition system, lighting) of gas-consuming equipment from the harmful effects of stray currents. The insert is installed between the gas cock and the gas supply. Of course, a gas meter can also suffer from stray currents. And, importantly, the insulating insert eliminates the possible heating and even sparking of the metal gas supply as a result of the accumulation of electric potential on it.
There are several reasons for the occurrence of stray currents, or leakage currents. The main ones are:
- Damage to the insulator on the gas line. To prevent corrosion, steel pipes of main gas pipelines are specially supplied with a small electric potential, which must be extinguished at the entrance to an apartment building or at the exit from the gas distribution unit in the immediate vicinity of the outlet to an individual house. For these purposes, a special main dielectric insert is used. In the event of its destruction or absence, the electric potential freely penetrates into the intra-house and intra-apartment gas pipelines.
- Lack of electrical grounding, faulty wiring and 
local electrical circuits. Modern gas consuming appliances (gas boilers and water heaters, stoves, ovens, etc.) are often stuffed with electronics and local electrical circuits. These are electronic control modules, and electric ignition, and timers, and lighting systems, etc. In the absence of the necessary electrical grounding, as well as when electricity hits the metal case of the equipment due to a malfunction of local electrical circuits (the so-called breakdown to ground), such equipment itself becomes a source of harmful currents.
- Illegal grounding of electrical appliances on gas steel pipes. Often your neighbors, who entrusted the work of connecting certain electrical appliances to "craftsmen", are happily unaware of the fact that their (neighbor's) electrical appliances are grounded on a gas pipe.
SPECIFICATIONS:
Mounting dimensions insulating inserts: 1/2", 3/4";
Execution option: fitting-fitting;
Material of metal parts: brass CW614N according to EN12165, similar to sanitary brass LS59-1 according to GOST 15527;
Dielectric: Polyamide according to GOST 14202-69 with fire resistance category PV-0 according to GOST 28157-89;
Nominal pressure PN=6 Bar (or about 6 atm). For reference: according to SNIP 2.04.08-87, in intra-house and intra-apartment gas pipelines, gas pressure up to 0.03 atm is considered normal;
A conversion table for pressure units is available on our website.
Electrical resistance: more than 5 MΩ at U=1000V;
Operating temperature range: from -60 to +100 degrees. Celsius.
The use of an insulating insert is regulated by the Letter of MOSGAZ No. 01-21/425 dated 12/26/2008: "... When connecting gas stoves to a flexible supply, provide a dielectric insert."
Dielectric insert:
In order for the stray electric current generated in the gas pipeline not to damage the gas appliances installed in our houses and apartments, special dielectric inserts or gas couplings are used, which are installed between and the gas pipe. What is a "stray current", why does it arise, how dangerous is it and how to protect gas appliances from it?
A stray current appears in the ground when there is a failure in the operation of power transmission lines, it can occur due to an accident on an electric railway or tram tracks, in case of an emergency condition of power lines.
The difference between the specific resistance of the earth and the steel structures of gas pipelines is so great that the current does not go into the ground, but into these very metal structures. Due to the fact that both household and main pipelines are made of metal, stray current goes straight into our gas system.
A stray current suddenly appears when the installation is incorrect, the boiler or column is connected to electricity. It turns out that the stray current is a real serious problem for the safety of not only one single apartment, but the whole multi-storey building.
Insulating barrel and squeegee
The use of dielectric inserts for gas: what is needed and their functions
1. As a result of exposure to stray current, your gas appliances may lose their performance or become sources of stray current themselves.
2. If there is a stray current in the pipeline, then during a thunderstorm or an emergency on the power line, a person can be seriously injured with the most serious consequences.
3. As a result of the occurrence of a stray current, a spark may appear in the gas pipeline, which causes a real threat of fire, and in the event of an explosion of the gas mixture, not only one apartment, but an entire multi-storey building can fly into the air.
A dielectric insert is far from someone's whim, it is a duty to install for someone who has gas equipment connected to electricity in his house or apartment.
That is why, when laying a gas distribution pipe, the performer of the work must be guided by the set of rules (SP 42-101-2003, paragraph 6.4), which refers to the mandatory installation of a dielectric, even if the pipeline is not made of metal, but, suppose, of polyethylene.
Types of dielectric inserts for gas
Dielectric inserts for gas are manufactured by our industry in several versions. They are usually divided into two main types:
1) insulating sleeves, barrels, squeegees, taps;
2) dielectric bushings.
Dielectric coupling for gas
Couplings are devices at the end of which there are internal threads. Couplings are installed between the gas appliance and the gas pipe.
Dielectric couplings are conditionally divided into 3 main types, differing from each other only in the diameter of the thread:
— ⌀ 15 mm or 1/2′;
- ⌀ 20 mm or 3/4';
— ⌀ 25 mm or 1′.
This division by thread size allows you to install couplings on any pipeline system with absolute accuracy, since thread diameters less than 1/2' and more than 1 1/4' are not used in our gas pipeline system. Dielectric couplings are not only desirable, but mandatory when installing hoses for gas appliances.
Valve with insulating sleeve
Dielectric couplings can be classified not only by the size of the thread, but also by the way they are connected:
1. Barrel ("fitting-fitting"): both ends have an external thread.
2. Barrel ("nut-fitting"): one end has an internal thread, the other has an external thread.
3. Coupling ("nut-nut"): both sides with internal thread.
Unlike a coupling, a sleeve is an insert that does not allow electrical current to pass through. It is installed between the gas pipe and the piping. Bushings differ from each other only in their size, that is, the size of the diameter of the liner. It is customary to use bushings with a diameter of 8 to 27 mm.
Dielectric sleeve for gas
With all the differences, both couplings and bushings have such common indicators as:
- made of non-combustible material, polyamide, which has a very high level of resistance up to 5 million ohms;
- have approximately the same strength indicator: the working pressure of both couplings and bushings is 6 atmospheres, and the maximum withstand pressure is about 493 atmospheres.
How to install the dielectric insert correctly
Both the coupling and the sleeve are installed between the gas pipe and the hose. If you install the dielectric yourself, pay attention to the order and sequence of your manipulations.
1. Shut off the gas in the pipe through which it is supplied to the gas appliance.
2. In order for the gas in the liner to burn out to “zero”, you need to leave the burners on gas appliances open.
3. Prepare two adjustable wrenches.
4. Hold the valve on the pipe with the first key, and unscrew the flexible hose nut with the second (the presence of two adjustable wrenches is mandatory so that the gas does not rush out).
5. Screw the hose nut, through which gas flows from the pipe to the gas appliance, to the end of the coupling.
6. Check your work for leaks by applying a soapy solution to the joint with a shaving brush.
Open the valve, make sure there are no bubbles at the joints, if there are none, then your job is done correctly.
Correct installation of the dielectric insert for gas
Dielectrics are presented on our market in a large assortment and in various price categories. Here you can buy a product for just a hundred rubles that suits you in terms of quality, or you can pay several thousand for foreign-made products. So the choice, as they say, for every taste and budget.
Manufacturers and prices
To feel the difference in price, let's compare just a few dielectrics of domestic and foreign production. The Tuboflex trademark (a Turkish brand that has passed the Russian campaign) is now in good demand:
- bushing, gas connection (thread-thread) "TuboFlex", price 159 rubles;
- bushing, nut-nipple connection, "TuboFlex" ⌀ 20 mm, price 146 rubles;
- coupling "Lavita" HP 20mm, thread ⌀ 3/4 ′, price 250 rubles;
- detachable clutch "Viega Sanpres 2267-22X1", price 3075 rubles;
- detachable clutch "Viega G3 Sanpres 2267-20X1", price 4033 rubles.
Today we have analyzed dielectric inserts (couplings, bushings), application, why they are needed, their characteristics and prices. We considered the types of dielectrics and the differences between insulating threaded joints. Let's watch the video.
Dielectric insert (insulating insert, dielectric insert for gas) -
This is a device that prevents the spread of so-called leakage currents (stray currents) through intra-apartment or intra-house gas pipelines. The dielectric insert not only eliminates possible heating and sparking of the supply line in the event of an accumulation of electrical potential, but also protects the electronics and internal electrical circuits of gas appliances and meters from failure due to exposure to harmful stray currents.
The main causes of leakage currents include the following:
- Common insulator damage at the inlet of the main pipe to an apartment building or an insulator at the outlet of a gas distribution point (node). To protect against corrosion, a small electric potential is specially applied to the main pipes. In the event of damage to the common insulator, this potential freely enters the intra-house and intra-apartment gas pipeline.
- Faulty or missing ground electrical wiring in the house. Modern gas-consuming equipment has its own electrical circuits (electronic control units, electric ignition systems, lighting, etc.), and, in the absence of electrical grounding, as well as in the event of a malfunction of the internal electrical circuits of gas-consuming equipment, these devices themselves become sources of stray currents.
- Unqualified connection electrical appliances and their illegal grounding your neighbors (or "craftsmen" hired by them) on hard gas pipes and risers.
Dielectric insert is an integral connection and is installed between the gas cock and the gas supply. The metal parts of the insert fused into the dielectric do not touch each other, which makes it impossible for leakage currents to pass through it (the insert). insulating insert has an inner surface completely covered with a dielectric, which excludes the contact of each of the metal parts of the insert with the gas passing inside the insulator.
Materials used:
- Metal parts: Sanitary brass LS59-1 according to GOST 15527;
- Electrical insulator: Polyamide according to GOST 14202-69 with fire resistance category PV-O according to GOST 28157-89.
Specifications:
- Nominal pressure PN 0.6 MPa, which is 200 times higher than the normal gas pressure in household gas networks (according to SNIP 2.04.08-87 and 
3.05.02-88, gas pressure up to 0.03 atm is considered normal);
- Operating temperature: from -60 to +100 degrees Celsius, which makes it possible to install the insert in unheated rooms;
- Pipe thread, 1/2" or 3/4";
- Inner passage diameter: 10.0 mm (for 1/2") and 14.5 mm (for 3/4")
- Electrical resistance at a voltage of 1000V more than 5 MΩ;
- The insert does not require maintenance during operation.
Employees of gas services in some regions are already using a dielectric insert in in-house and in-house gas pipelines without fail. In particular, its use is regulated by the order of MOSGAZ of December 26, 2008 No. No. 01-21/425: "When replacing gas stoves and connecting them to a flexible supply, provide a dielectric insert."
"Small spool, but expensive" - this expression is the best suited for inserting a dielectric. The cost of this product is negligible even compared to the cost of possible repairs of electronic and electrical components of modern gas equipment, not to mention the consequences of emergencies such as fire or explosion.
Dielectric gas coupling provides safety in residential areas, and saves people's lives.
Equipment running on natural gas is connected to electricity sources. To prevent an accident when electric current enters the gas pipeline network, a protective insert should be mounted on gas appliances.
The purpose of the dielectric coupling for gas
Boilers and boilers are used to heat the water in the heating system. For cooking, stoves, ovens and hobs are placed in the kitchen. In the listed devices there is a system of control sensors, electric ignition, oven lighting. Therefore, the gas type of the device requires connection to the electrical network.
So that the current does not flow through the gas pipe inside the room, polyamide insulators are used - couplings. For the dielectric coupling for gas, yellow polyamide is used due to the low content of conductive impurities.
Dielectric insulating inserts, when current enters the gas network, will maintain the performance of gas devices and gas meters.
How does a breakdown occur in the gas network
Natural gas is supplied to homes and other premises through metal pipes laid underground in urban areas or above its surface in the private sector. Metal corrodes when exposed to moisture. Applying a positive electrical potential helps to reduce the degree of corrosion.
According to the safety regulations, a dielectric coupling is installed on the pipe at the entrance to the house. In this way, the indoor gas riser is protected, provided that the coupling is installed correctly and in good condition. But the deaf grounding of the pipe in the basement of the house can break due to corrosion.
Further, in a house or apartment, suppose the stove is connected to the riser through a rubber hose with a metal braid. If suddenly the insulation of the electrical wire in the plate is broken, the current will go through the hose braid. Depending on the strength of the current, the time for heating up and breakdown of the hose will be short or long, but a breakdown will definitely occur.
Sometimes residents of the house arrange grounding on the gas pipe.
Possible fire due to a gas leak in the apartment. Everything can do without victims, but with material losses. After such an event, the question of why a dielectric coupling for gas is needed will no longer be hypothetical for residents.
How the clutch works
Details of the gas network are produced in several types according to the type of fastening: "fitting - fitting", "nut - fitting". The product is one-piece, non-separable, and therefore safe to use. Any excess connection is a source of gas leakage.
High-quality couplings are made of brass, the thickness of the tube is not less than 4.5 millimeters. The insulating part is made of yellow polyamide, which includes a "flame retardant".
The choice of eyeliner and coupling
It is better to choose a bellows eyeliner coated with a yellow insulator. It is easier for housewives to wash such an eyeliner from dust and kitchen soot. At the same time, the insulator will protect against the flow of current when touching the bare terminals of live devices or the conductive body of the device.
Of course, an inexpensive rubber hose could be supplied. But rubber tends to age, lose elasticity, microcracks appear on the rubber hose - places of gas leakage.
Dielectric couplings for gas will protect against the flow of current through any hose. These parts are tested for breakdown with a current of 50 Hertz and a voltage of 3.75 kV for 6 seconds or more. When a voltage of one kilovolt is applied, the electrical resistance is 5 megaohms. Inserts withstand temperature differences from -60 to +100 degrees. Insulator manufacturers guarantee a service life of at least 20 years.
By installing a dielectric coupling for gas, leaving the house on business or taking a bath, the reader will be confident in the safety of home, loved ones and neighbors. Dielectric insulator - protection against burning of the eyeliner, subsequent gas leakage and inevitable explosion.
