Natural gas provides people with heat and hot food. However, to implement these functions it is necessary to connect it to the home - to install a pipeline connected to the central network, heating equipment and household appliances.
At the stage of pipeline design, it is necessary to figure out what permits need to be issued, how to properly cut into the gas pipeline and who to entrust such responsible work. The answers to these questions are described in detail in the article.
In addition, we described different methods of connecting to the central line, and also outlined the features of connecting to a plastic and metal pipeline.
A gas pipeline is a specialized pipeline whose purpose is to transport and store certain volumes of blue fuel. It may have different design features, differing depending on the tasks assigned to the highway.
For example, networks of international importance deliver huge volumes of gas to long distances, because they maintain constant pressure at high level. That is why any experiments with gas supply systems are inappropriate and can be dangerous not only for you, but also for others.
Which means the best option To carry out work with the system, you will need to call the appropriate services specializing in working with gas communications, which meets the requirements of the law.
The insertion into the gas pipeline must be carried out by a gas service specialist who has required level clearance and observing all safety measures
Gas pipelines are arranged similarly circulatory system human body. Their role can be compared to the coronary vessels. And from the central pipes, regional pipes depart, distributing blue fuel among consumers.
They are smaller than the main ones, and therefore the pressure in them is much lower. However, even in such gas networks, its jumps are possible both in a decreasing and in an increasing direction.
Connection to gas communications occurs if the organization has a special permit. And you can try to do the wiring inside your home yourself. To do this, you just need to know a clear sequence of actions and adhere to necessary measures security.
Rules for calculating throughput
The main factor responsible for the continuous supply of blue fuel to consumers is the throughput capacity of the gas pipeline. This parameter is calculated using a special algorithm. Moreover, it is done regardless of the type of pipes used.
The maximum throughput can be calculated using the following formula:
Q max. =196.386×D²×P/Z×T,
- R– operating pressure maintained in the gas pipeline, plus 0.1 MPa or absolute gas pressure;
- D– internal diameter of the pipe;
- T– temperature of the pumped blue fuel, measured on the Kelvin scale;
- Z– compressibility coefficient.
This formula establishes the following pattern: the higher the value of the T indicator, the greater the network throughput should be.
Otherwise, the gas transmission line will depressurize, which will inevitably lead to an explosion of this dangerous substance.
Having made a choice of the type of pipes for a gas pipeline, it is important to correctly determine the insertion method
There is a more complicated formula. However, the algorithm given above is quite sufficient to perform the necessary calculations prior to inserting into the gas pipeline.
How to properly connect to a gas pipeline?
Tapping into the backbone network cannot be done with your own hands - only with the help of specialists gas companies who have permits and permission to carry out such work. Regardless of the chosen company, there will be a large-scale preparation stage before connecting to communications.
Preparing for the tie-in
If you decide to entrust the process of connecting to the gas network to specialists from the relevant company, then you need to contact the permitting service. Here, in addition to submitting an application in the established form, you will need to provide a package of documents required by law.
On the eve of the connection into the gas transmission main, it is necessary not only to make correct calculations, but also obtain permission from gas workers
When it comes to inserting a newly constructed building into the gas pipeline, the owner should first of all provide a passport, identification code and approved one.
In addition, you should prepare a set of documents:
- statement, certified personally by the head of the territorial gas sector department;
- connection permission to the gas transmission main, issued by the architectural planning department;
- photograph, made during the topographic survey of the area where the insertion will be carried out;
- technical passport for a private house, or a copy thereof certified by a notary.
The photograph must be certified by authorized gas service employees. It will depict the entire engineering infrastructure, including not only gas communications, but also water supply, heating network pipes, and sewerage.
If the house is under construction, then an appropriate architectural design, a permit for its construction and a floor plan should be provided.
And if its total area exceeds 300 sq. m., it is necessary to submit a thermal calculation of the building, a situational plan of the site on a scale of 1:5000, and consent of the neighbors to connect to the gas network, drawn up in writing.
The latter document will be needed in the case when it is planned to run part of the gas pipeline underground through areas they own.
On the eve of work on laying a pipe for insertion into a gas pipeline, it is necessary to obtain a documented permit of the established form
In most cases, permits of this kind are issued by the city gas department, since they are the rightful owners of gas transmission lines.
In addition, you will need to provide technical passports or other documents attached to the gas appliances that are planned to be installed in the building - permission to use the equipment at your place of residence, certificates of conformity, as well as service contracts.
You will also need an inspection report for smoke ventilation ducts and other documents required by law. Only having all the permits and acts in hand can you begin to carry out tie-in work, i.e. exclusively on a legal basis.
It must be remembered that unauthorized connection to the main gas pipeline, without registration in established by law the procedure for proper documents and coordination with the relevant services is fraught with administrative measures. And if at the same time there was damage to the gas pipeline, then there will be criminal penalties.
Features of the tapping process
The process of tapping into a gas pipeline is the connection of a new pipe, through which the substance will be transported from the central pipeline to the consumer. As a rule, connections of this kind are made without cutting off the gas supply in the main network.
An example of tapping into a gas pipeline under pressure in the video:
Having general idea O technical requirements and the procedure for carrying out work on connecting to the gas network, it will be easier to navigate all the nuances, and it will also become easier to control the work of the company with which the connection agreement has been concluded.
In addition, the absurd desire to cut into a gas pipeline yourself will disappear, inviting a handyman in order to save money.
Share with readers your experience in coordinating documents and connecting to the central gas pipeline. Please leave comments on the article and ask questions that interest you. The feedback form is located below.
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Any engineering structures, including gas supply pipes, have their own service life, after which they must be dismantled and replaced. If you are planning a home renovation, then it is worth remembering these parameters so that all cosmetic work can be done after servicing the home gas pipe.
In this article we will tell you how to make an insert into gas pipe to replace it, and what subtleties need to be taken into account in this process.
Specifications
Uninterrupted gas supplies to consumer homes directly depend on the throughput of gas pipes. In this regard, the calculation of this parameter is carried out especially carefully. Moreover, this process is mandatory regardless of the material of the products used - polymers or steel.
To determine the maximum throughput of each specific pipe, the following formula is used:
Q max = 196.386 T×(P/Z)×(D y /2),
where P is the value of constant operating pressure in the gas pipe, increased by 0.1 MPa; D y – size conditional passage pipes; T – indicator of the temperature of the gas passing through the pipe in degrees Kelvin; Z – compression ratio.
Based on the formula, we can conclude that the higher the temperature of the gas transported through the pipes, the greater their throughput must be in order to prevent leaks, loss of tightness or even explosions.
Although in professional work craftsmen often use more complex formulas to calculate throughput, the above calculation method is still more than enough to independently select pipes of the required diameter.
However, to make your task easier, you can take ready-made data from a special table that shows the throughput of pipes depending on the gas pressure in the system.
Preparing to replace gas pipes
Thanks to its complex design The gas supply system performs two functions at once - gas transportation and storage. Depending on the main purpose, different systems may have their own characteristics. In particular, main gas pipelines, the main task of which is to supply energy over long distances, are characterized by high pressure levels in the system.
Therefore, tapping into a gas pipe under pressure poses a great danger to an untrained person. Such actions can pose a danger not only to the employee himself, but also to the life, health and property of others. Consequently, illegal tapping into a gas pipe, without the involvement of specialists with the appropriate level of clearance and professional skills, is strictly prohibited.
If you do not know how to connect to a gas pipe, or there is a high-pressure line next to your house, you should contact a special service to replace communications in the house, and under no circumstances do such work yourself.
At the same time, it is unlikely that your pipes will be replaced on the first visit of a gas worker. Usually he first measures the length of individual components of the system, carries out visual diagnostics condition of the pipes, after which within a few days it is construction estimate. In it he gives everything specifications required tubular products, describes the cost of materials and labor.
Standards for safe tapping into gas pipes
Before crashing into a gas pipe, you need to take care to comply with safety regulations at the site. There should be no open sources of fire near gas pipes, so the work site must be isolated from smokers and strangers in general.
In addition, at the approach to the point of connection into the gas pipeline, warning signs should be placed with the inscriptions “Caution, gas!”, “Passing is prohibited!”, “Smoking is prohibited!” and others with similar content. Such requirements are mandatory to comply with in order to avoid accidents.
When making connections into a gas pipe, you must also follow certain standards for working with them.
The most significant rules are:
- when connecting to a gas pipeline with low pressure, it is necessary to ensure that its value does not rise above 80 mm Hg, but also does not fall below 20 mm Hg;
- if work is planned in networks with high or medium pressure, then before starting the tie-in, this indicator must be lowered to an acceptable level;
- gas cutting or welding of pipes can be carried out only on those sections of the pipeline where the pressure fluctuates between 40-150 MPa. Moreover, it is important to ensure that this indicator remains within acceptable limits throughout the entire period of work.
A standard has been established by law according to which only enterprises that have received a special permit or even an order to do so can tap into gas pipes without reducing the pressure level in them.
Please note that those cases where it is not possible to reduce blood pressure are rather exceptions, non-standard situations. Under such circumstances, special equipment is required to carry out repair work.
Types of insertion and preliminary actions
Stage preliminary preparation is a must in any case, whether you are a beginner or an experienced master. If you yourself do not know how to cut into a gas pipe without welding or in any other way, contact an office that specializes in such work.
When contacting a contractor, when filling out an application to perform a tie-in, you may be asked to present a whole package of documents required by law for such cases.
When making the initial connection to the gas main of a newly built house, the following documents will be required:
- permission to tie into the gas main from an architectural planning institution;
- topographical photograph of a specific area, certified by the gas industry. In addition to gas pipes, it must indicate all communications connected to the building: water supply and sewerage, heating;
- technical passport or its copy, certified by a notary, a number of other documents.
But those owners who understand the intricacies of cutting into main gas pipelines, and are also quite confident that they can cope on their own, only need to purchase the necessary materials. However, be careful, as crashing into a gas pipe is illegal and not entirely safe. If the technology is violated, it can cause damage to the main line, which can result not only in harm to life and health, but also in administrative and criminal liability.
Connect the operating gas pipeline to new branch possible in two ways.
Cold tap
IN in this case the main pipe continues to operate normally without changes in the volume and pressure of the transported gas. This method is preferred for the initial connection of new subscribers.
Those who prefer to tap into a pipe under pressure themselves most often prefer this technology, since it is the easiest to perform.
Welding method
But the method of connecting gas pipes to the main lines can be reel or tee. With a coil connection, the ends of the pipes and the operating system are joined, and with the T-bar method, the axes of the pipelines are crossed.
Connecting the system to the gas pipeline
To tie into a common highway, it will be necessary to carry out the following measures:
- Clean the connection area from debris, rust or paint.
- Perform markings, mark the insertion location.
- Make holes, of which there will be two - in the case of the T-bar method, and one - in the reel method.
- Cover the cracks with clay. Processing should begin at the moment the surface begins to be cut. This will reduce the risk of gas fire. Immediately close the holes made with a plug made of clay and asbestos, and cool the surfaces after finishing the work.
- Install the disconnecting device after the metal has completely cooled. To do this, pull out the plug and remove part of the cut pipe. After this, insert the disconnecting device into the resulting gap - it looks like little bags made of viscous clay and several rubber and wooden disks. If the T-bar method is used, there will be two slots.
- Now you need to mount the pipe through which the gas pipe is connected to the main line. But first check that the diameters match. If nothing needs to be adjusted, then make a hole and mount the pipe, then weld the joints and close the valve installed on the pipe.
- We close the holes and weld a new pipe. First, get rid of any remaining metal that was created during the process of creating the main gap. After this, connect the pipe to the pipe, treat it with clay and brew it. The quality of the weld is checked with a soap solution.
It is worth noting that welds and their types have strict designations and comply with GOST standards. In this regard, work must be carried out only taking into account all the requirements and standards that correspond to the characteristics of our gas pipeline.
If no leaks were found, then you can proceed to finishing work - that is, backfilling the trench. Despite the fact that the work may seem very simple, it must also be carried out in compliance with regulatory documents.
Typically, such documents contain the following information:
- Soft soil no more than 20 cm thick is poured around the mortise unit, pipe and tap, followed by compaction.
- At the very end of filling the soil into the trench, heavy equipment should not be allowed to collide with pipes, mortise units and ball valves.
Upon completion construction work You will need to sign an agreement with the local gas service to begin supplying blue fuel. In addition, the gas service will be required to provide technical and emergency dispatch services. The same organization will be responsible for accepting the finished gas pipeline system. After starting and setting up work, it is necessary to draw up a report and also seal the gas control system.
Replacing gas pipes in an apartment, like any other pipelines, is required after many years of use. Therefore, if you plan to make repairs, pay attention to the service life of gas pipes, since leaks may occur in old pipes and, changing them, the repair will have to be redone at least partially.
Cutting old pipes is done with a grinder, and the products of such work will certainly not go unnoticed on the walls and other interior elements.
Replacing a gas pipeline in an apartment
As you know, replacing gas pipes with your own hands is prohibited, so only specialists from gas service companies are allowed to do this type of work.
Therefore, if a replacement is necessary, you will need to contact the appropriate institution and wait for the technician to arrive.
Most likely, the first visit of a gas service employee will not replace your pipe, since the technician will need to inspect the gas system, measure the length of the gas pipes, draw up an estimate for the work, as well as the cost of new pipes for the household gas pipeline.
Gas pipe replacement work
Having arrived at the installation site, the technician must remove unauthorized persons from the site and ensure that there are no smokers or sources of open fire.
Before entering the work site, a warning sign “Caution! Gas!”, “Smoking is prohibited!”, “No entry!” etc.
Before cutting a gas pipe and starting work on installing a new one, the gas worker must block the access of gas to the gas pipeline to which the new pipe will be welded and remove (blow out) the remaining gas from it. Blow gas into the room ( ventilation ducts etc.) is strictly prohibited.
Once all safety precautions have been taken, the gas pipe can be trimmed. As already mentioned, it is usually produced using an ordinary grinder. Next, a new one is welded in place of the old pipe.
Checking the integrity of the household gas pipeline and rules for starting gas
The release of gas into the pipe is prohibited until its integrity, the presence of all required plugs and the serviceability of the connected gas equipment are confirmed by inspection and appropriate tests (soap emulsion).
When starting gas, the gas pipeline must be purged until all air is displaced from it. The duration of purging is determined by analyzing the gas samples taken.
The oxygen content in the gas should not be more than 1%, the combustion of the last sample should proceed smoothly, without popping. When blowing the gas pipeline, after the gas pipe has been replaced, it is prohibited to release the gas-air mixture into the room, ventilation outlet, staircase, etc. When starting gas, the room in which installation work is carried out must be provided with constant ventilation.
During and after the release of gas into a newly connected outlet of the gas pipeline system, it is necessary to ensure enhanced monitoring of the operation of the gas system.
Tapping into a gas pipeline
Apartment buildings are often equipped with a gas pipeline system even before residents move in. But what if you need to tap into the gas pipe of a newly built house? Let's describe what the gasification procedure at home looks like.
Preparation of necessary documents
The list of documents required to connect gas to the house is as follows:
- those. home passport or certified copy;
- a photograph of a topographic survey of the site on a scale of 1:500, certified by the gas service, with a gas pipeline and other communications marked on it (,);
- permission to connect an architectural and planning institution to the gas pipeline;
- documents for equipment planned for installation in a house to which gas will be connected - a certificate of conformity, a contract for servicing the equipment, a conclusion that it is subject to use in house construction;
- inspection report (VDPO), received after contacting Gorgaz.
How to obtain permission to tap into a gas pipeline
In Gorgaz you will need to find out which design organization for gasification of the house they recommend, since this will be the key to the absence of problems in the future. You will need to agree with the design engineer on the placement project and brand of gas equipment and heating appliances, after which the specialist will independently have to approve the project in the technical department of Gorgaz.
Read the contract carefully. You should be interested in items with clearly stated guarantees on the part of the contractor.
Installation of a domestic gas system and connection to the gas pipeline
After installing the gas pipeline and equipment, the design organization draws up a package of as-built technical documentation. The work is accepted by a special commission consisting of a representative of Gorgaz, the contractor and the customer.
You will also need to pay for the technical inspection receipt and provide a copy of it to the installation company. In the near future, representatives of Gorgaz will seal the meter, and an agreement will be concluded with the customer for the supply of gas and maintenance of the part of the gas system belonging to it.
Don't know how to crash into a gas pipe? To do this, you will need to hire a special service that carries out tie-ins.
Having connected you to the gas pipeline, specialists will open the gas tap and perform a test run of gas, thereby checking the entire system for leaks.
Having made sure that everything is in order, all you have to do is carry out commissioning of the equipment, which, however, can also be carried out by the selling organization, of course, if you have an appropriate agreement for technical and warranty service.
It is impossible to join a gas pipeline and a gas-consuming facility that is newly built and operating, as well as those that have not been accepted by a special commission, and is also prohibited. To connect such facilities, an act of acceptance for operation is required, in accordance with instructions approved by the head of the engineering department of the gas enterprise.
You can only join a gas pipeline system that is in operation when releasing gas into gas channels or objects. And at the end of the gas wire that is connected, it is necessary to install a barrier cap. If there is a special disconnect device at the end of the gas pipeline system, which means that the barrier cover must be installed after it. Gas supply channels to the premises are still preparatory stage, before the connection process, must be disconnected from the internal gas pipeline.
To commission a gas pipeline industrial production or agricultural or municipal enterprises, it is necessary to report the connection of the gas system of the enterprises to the city distribution source to the city gas service in order to launch the gas substance into the enterprise network. Also inform the district office of the city gas service by submitting a corresponding application from the enterprise.
Then, when the enterprise receives gas from the gas main, its gas pipeline must be connected to the gas main on the basis of an act on the acceptance of the gas system. Work on cutting into the gas main is carried out by a special gas service.
All gas pipeline structures and gas facilities, before connecting them, are subject to external inspection and pressure testing. Pressure testing is performed using air or inert gas. The process of crimping external gas pipelines of any pressure must be carried out under a pressure of 0.02 MPa. The pressure indicator may drop, but not more than 10 daPa per hour.
The control process of pressure testing of internal gas pipelines of industrial or agricultural enterprises, an enterprise that serves the population and has production tasks, instruments and devices of the gas pipeline system must be performed under a pressure of 0.01 MPa. But the pressure indicator can only drop by no more than 60 daPa per hour.
Under a pressure of 500 daPa per hour, the internal gas pipeline system and equipment of the enterprise, which serves the population and has non-production tasks, residential buildings and public buildings. The pressure indicator when falling is no more than 20 daPa for five minutes.
Tank with liquefied gas, the gas pipeline system of the group cylinder installation is tested by a control process at a pressure of 0.3 MPa in an hourly period of time.
As a result, the tests can be considered positively completed, provided that there are no moments when the pressure drops or leaks. This is determined using a pressure gauge and a soap emulsion.
The results obtained are formalized in a report and written down in the order for performing dangerous tasks. gas works. The air pressure indicators in the gas pipeline system that is connected must be maintained until initial stage connection process and gas start-up.
In the case when gas pipelines that have passed the inspection and those that have been tested with control pressure indicators are not filled with gas, then in the conditions of restoration of gas startup work, they must undergo inspection and pressure testing again.
Gas penetration and welding work on gas pipeline structures that operate in normal mode, in the case of connecting other gas systems to them, must be carried out under gas pressure within 40-150 daPa. These indicators are checked throughout the entire time period while the work is being carried out. In the event that the pressure begins to drop below 40 or rise above 150, cutting and welding work must be stopped. Monitor blood pressure readings required area necessary using the installed pressure gauge.
The moment the pressure indicators in the gas pipeline system decrease under the conditions of cutting in occurs with a special shut-off device or indicator regulator. If special devices are used that ensure complete safety and execution of processes at a high-quality level, it is allowed to connect without reducing the pressure indicators. The method by which the gas pipeline will be connected to the one that is already in operation is established by the enterprise.
The procedure for cutting into gas wires using gas is carried out according to the instructions developed by gas industry enterprises. The presence of persons outside the process, smoking and open fire It is prohibited to perform cutting-in work in the area.
Various holes on the ground during cutting work must be fenced off near the work site by posting warning signs: It is forbidden to pass!, It is forbidden to smoke! and Attention! Gas! Be careful!
It is also prohibited to start gas into gas system unless it has been verified for integrity through inspection and testing procedures, in addition to the serviceability of gas fittings and the presence of required barrier caps. Gas is introduced into special equipment for residential premises before the residents of the house have moved into it.
When starting gas, gas pipeline structures must be purged until all the air is displaced. The completion of the blowdown can be determined by analysis or by burning the samples that are taken. In this case, oxygen should not be contained in the gas in more than 1%, and a test sample of the gas should burn without emissions and in a fairly measured manner.
When blowing out a gas pipeline, it is prohibited to spray a mixture of gas and air in the building, on staircases, in chimneys and in the ventilation system. The building where gas consuming appliances, gas pipelines, gas equipment When starting a gaseous substance, it must be regularly ventilated.
In case of blowing through the gas pipeline, the mixture of gas and air should be released in an area that eliminates the risk of it passing into the room, in addition, where the formation of a flame from any fiery source is excluded.
When starting up a gas resource for the first time, you need to carefully ensure that it is supplied with pressure indicators that do not exceed those for which the gas pipeline system was designed. At the time of launch and immediately after this, it is necessary to vigilantly monitor the entire gas supply system, in the case of laying underground behind all objects, including a basement, well, buildings, which are located in an area within a radius of 15 meters from the gas source of the gas pipeline. Increased monitoring is necessary in winter and spring period, when a frozen soil mass above a gas pipeline structure can make it difficult for gas to escape from underground. Do not forget that when gas flows from a gas channel underground, it moves through the soil mass at a speed of up to 7 meters per hour.
Work processes related to connecting a new gas pipeline to an already fully operational one must be carried out by specially trained people under the supervision of gas industry specialists.
Work on connecting to the gas network is considered gas hazardous and is carried out according to a scheme that has been approved in advance. Orders are made for such work. In the preparatory stage of the work process, a drawing of the connecting nodes is necessarily carried out, a method for connecting work is determined, the procedure for reducing pressure in the gas pipeline is calculated, of course, where it is required, and they are ensured in a stable condition for the entire period of connection. Also calculated necessary materials, protective equipment, rescue equipment, first aid medical care. In addition, barrier caps and valves on the gas line that is connected must be closed.
Connection methods
So, several ways are used to connect a new gas pipeline to an existing one, such as:
1. Connect using gas (low pressure readings within 40150);
2. Connect under high and medium pressure without reducing it, using special devices;
3. Connect the pipes, disconnecting them and freeing them from gas.
When performing work, there is an option to turn off the gas locally using a wooden disk, a piece of burlap, a clay mass, or a rubber chamber.
Connecting a new gas pipeline in a way when you need to disconnect the existing one, using a rubber chamber, is acceptable for a gas pipeline that has a diameter of up to 60 cm. The pressure indicator must be reduced to 150. First, you need to check the hand pump for serviceability and the sealing properties of the chamber. It is necessary to install a certain type of pressure gauge and monitor the pressure.
The procedure is as follows:
1. Using an autogen, a hole is cut in the gas line that is operating. The hole diameter is about 10 cm.
3. A chamber must be inserted into the channel through the hole and filled with air mass, ensuring strong contact with the walls of the channel.
4. The area that is disconnected is blown through the hole.
5. Then, it is necessary to cut into a new gas pipeline that has a barrier cover.
6. Finally, the chamber should be removed from the working wire, the hole should be welded, pressure restored, and the tightness properties of the connecting section checked.
Attach using a visor
1. The area where the connection will be made is cleared of insulating residues.
2. Mark with chalk and cut the end of the pipe together with the steel barrier cap. Then the canopy is cut into the extension to a size that ensures unimpeded removal of the disc that is being cut out (the wall).
3. On the gas pipeline, it is necessary to mark in small pieces the diameter size and its circumference, which is equal to the diameter of the product that is connected. Weld a rod in the center, the diameter of which is about 8 mm, and its length is about 20 cm. This is necessary in order to remove the piece of pipe that is being cut out.
4. Cut a disc along the intended circle, leaving a small piece of about 5 mm so that the disc is held. You need to cut downwards.
5. Extinguish the gas, cover the hole with a clay mixture along the trajectory of the cutting tool. If the putty dries out, then coat it again with the already diluted clay mass.
6. The flame is extinguished, the cutting area is cooled.
8. You need to insert a wooden disk with a seal into the extension through the hole. Fit the canopy to the extension and to the gas pipeline structure.
9. Remove the wooden product by knocking out the jagged surface of the wall with a hammer, remove it using a rod and press the visor tightly with asbestos applied. Leaks must be prevented by using asbestos.
10. Secure the visor with wire, the diameter of which is about 3 mm.
11. Blow the connection area thoroughly, removing all the mixture.
12. Weld the visor after cleaning it first.
13. Fit the pipes, install a steel gasket on top of the canopy and weld with an overlap. The gasket is 20 cm larger.
14. Before installation, heat the gasket with a gas appliance, bend it with a sledgehammer and fit it over the products so that it covers them.
15. Tap the connecting areas, clean them and check them under operating pressure using a soap emulsion. The area where the attachment occurred is cleaned and covered.
16. Install the control tube and fill the ditch.
End connection
1. Having cleaned the gas pipe, mark with chalk and cut out the visor, keeping a gap of about 50 cm from the steel barrier cap. The size of the visor should not interfere with the installation of the disk. Cut out the disc and cover the gap with a clay mixture. Cool the cutting area.
2. Separate the visor and install a disk inside the gas pipe that is in operation, which, in turn, is secured with a wedge and coated with clay mass. If the diameter of the product is less than 15 cm, then you need to put a plug in the pipe using bags and clay. Remove the chamfer and fit it to the pipe.
3. Mark and trim the ends of both structures and barrier covers. Remove chamfers.
4. Make markings and cut out the connecting node. The length of the assembly can be determined by breaking both gas pipelines, taking into account allowances for adjustment. Install the assembly, grab it and weld it at the connecting points.
5. After cooling the disk, remove it and apply a visor using sheet asbestos. Secure it with steel wire, the diameter of which is about 3 mm. Blow gas through the area to be connected.
6. Weld the visor, clearing the chamfer from dirt. Fit, install and weld the steel gasket.
7. It is allowed to use paste to seal cracks.
Connection using a slide-on product
1. Clean the connecting areas from insulating residues.
2. Prepare a pipe for connection (slide-on) with a diameter that is approximately 2 cm larger than the outer diameter of the gas pipeline that is being connected.
3. Prepare an external extension about 15 cm long, the diameter of which is 1.5 cm greater than the external parameter of the connection pipe. Install the extension, align it and attach it to the existing wire. The axes must coincide. Having adjusted the extension, weld it.
4. Cut off the barrier cap at the end of the gas line and slide the pipe on. Weld special ones to the ends of the pipes, the diametral parameter of which is 3 mm less than the outer parameter of the pipes and expansion.
5. Cut out the wall through the extension, leaving a jumper of about 4 mm. Remove the wall using a pre-welded rod.
6. Extinguish the gas using clay.
7. Pull the pipe. At one end it rests against the wall of the gas pipeline network, which is active, and at the other it moves at least 10 cm onto the product.
8. Use a hammer to cut the window and remove it, pushing it all the way into the gas system. Seal the gap between the walls with asbestos cord until the gas stops escaping.
9. Blow with gas until the mixtures disappear completely. Heat the ends of the products with a burner and roll them, then overlap weld them.
Then all procedures are performed in the same ways. The walls are removed and the gaps are sealed with an asbestos cord in a gas mask.
how to crash into a gas pipe at home Connection using a coupling is performed in the following order:
1. Clean the connection area. Prepare the coupling outside diameter which should be 2.5 cm larger than the external parameter of the connection pipes. The length of the product can be determined by the gap between the ends of the products and add 20 cm. The coupling is installed on the ends of the connection pipes.
2. Cut off the ends of the products together with the barrier caps. Extinguish the gas with a clay mixture. Weld the rings onto the ends. At the end of the pipe and weld both parts.
3. Check the coupling by sliding it onto the end of the second pipe. Separate the cut ends and barrier caps, then slide the coupling onto the second pipe. Both ends must be overlapped by a coupling by at least 10 cm.
4. Reinforce the gaps between the walls of the products with asbestos cord. It is necessary to compact until the gas stops escaping. After blowing through the pipes, heat the sides of the coupling with a gas appliance and press them with a hammer until they are completely connected to the pipes. Weld the ends of the coupling.
It can be connected via a bypass for the duration of the installation process regarding the shut-off equipment to the existing gas channel. In addition, in conditions of switching existing inputs of continuous gas flow. The diametric parameter of the bypass product is equal to a fifth of the diameter of the products that are connected.
The process is performed in this order :
1. Make a bypass product, the length of which is equal to the length of the section that is planned to be turned off and add 2 meters to it. Prepare two extensions 5 cm long; their internal diameter should be 1.5 cm larger than the external diametrical parameter of the bypass product.
2. Keeping a gap of one meter from the boundary of the area that is being switched off, mark a circle of diameter equal to the internal indicator on top of the pipe with chalk. Weld a rod 0.8 cm long and 20 cm long in the center of the circle. Weld extensions to it. Check the installation of the bypass in the extensions.
3. Inside the extensions, cut out disks in the walls according to the marks, leaving a 3 mm section. Extinguish the gas with a clay mixture.
4. Knock out the discs and remove them using a rod. Install a bypass from inside the extensions. Seal the joints with cord. Grab it to the expansion using welding equipment at 3 points.
5. On the marking sections of the pipes, cut a pair of canopies at a gap of 10 cm from the bypass product. Once cooled, separate them. Install a barrier cover through the hole from the inside.
6. After completing the work, remove the barriers, weld the visors, and place the disk on the hole.
7. Test the suture areas and isolate the work area.
Preparatory work for the pits and reception, insulating measures in the cutting areas and work on backfilling the pits are carried out by the company that built and connected the gas system. Before joining electrochemical agents must be disabled. Connection work under the influence of gas from inside the room is prohibited.
After all the work carried out, the tightness of the seams is checked with a special device or emulsion using pressure. It is also worth going around the gas main, marking the work performed in the work order, and recording everything in the passport. Attach the work order and diagram to the rest of the documents and keep them together.
To open the flange at the connection, devices are used, for example, a copper wedge. It is suitable for products with a small diameter.
If the diameter is more than 30 cm and it is necessary to open the flange, then fasteners are welded for mounting a jack between them. Can not use hydraulic jack. It is necessary to install wooden spacers to prevent it from falling. It would be better to secure it to the gas pipeline. During the installation of barrier covers, it is necessary to check the dimensions of the covers and whether they correspond to each other, you need to prepare gaskets and lubricate the bolts.
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