Laying a gas pipeline: methods, equipment, requirements. Gas pipeline security zone

Transportation of gas to the consumer.

Due to the remoteness of the sources from the place of consumption of natural gas, its delivery is carried out through main lines at a pressure of up to 5 MPa and a pipeline diameter of up to 1.6 m. In all newly laid gas pipelines, in order to increase the throughput capacity, the pressure is increased to 7.5 MPa. To maintain pressure when pumping gas over long distances, booster compressor stations are installed every 120-150 km. The transfer of flammable gas from the main line to consumers is carried out using networks of appropriate pressure (medium and low), GDS and hydraulic fracturing. Due to the great unevenness and seasonality of gas consumption schedules, it is necessary to make gas reservations. To level out seasonal irregularities and store gas, large-volume underground storage facilities (former oil and gas fields) are used. Daily and hourly uneven consumption is leveled out using special storage facilities and gas tanks. Due to the high explosion and fire hazard, gas networks, gas distribution systems and hydraulic fracturing units, shut-off and control equipment and equipment, in accordance with the current Construction Norms and Regulations, are subject to increased requirements. Gas can be delivered to local consumers using underground and above-ground installations. Underground installation is mainly used. Aboveground installation is allowed on the territory of PP, communal and residential areas under a number of specially specified conditions.

To supply gas from group installations, steel gas pipelines are used, laid underground and designed for a pressure of pure gas of 3–5 kPa, and of gas-air mixtures - 1.5–3 kPa.

Underground gas pipelines. The routing of gas pipelines through the territory of populated areas, inside blocks or courtyards should ensure the shortest length of gas pipelines and branches from them to residential buildings, as well as the maximum distance from above-ground buildings (especially those with basements) and non-pressure underground communications (sewer pipes, channels for heating pipes and others containers through which gas can spread). The routing of gas pipelines through undeveloped areas should be carried out taking into account the layout of their future development.

In accordance with the requirements of the current “Safety Rules in the Gas Industry” of the Gosgortekhnadzor of the Russian Federation, the horizontal distances between low-pressure gas pipelines (up to 5 kPa) and other structures must be clear, m, not less than:

To the foundation of buildings and structures, overpasses and tunnels - 2;

External lighting, contact network and communication supports - 1;

The axles of the extreme track of the railway gauge 1520 mm - 3.8;

The tram's extreme track axles are 2.8;

Side stone streets, roads - 1.5;

The outer edge of the ditch or to the bottom of the embankment of the street, road - 1;

Foundations for support of overhead power lines with voltage up to 1 kV and outdoor lighting - 1, above 1 to 35 kV - 5, and above - 6;

Tree trunks - 1.5;

Shrubs - not standardized.

When laying gas pipelines between buildings and under the arches of buildings, as well as in certain sections of the route where the given distances cannot be maintained, it is allowed to reduce them to values ​​that ensure the safety of all underground structures during the construction and repair of each of them. If it is necessary to reduce the distance, long seamless pipes with increased wall thickness are used; bent bends are used; welded joints are checked by physical control methods; The pipes are protected from corrosion by highly reinforced insulation.

The minimum horizontal clear distances between utility underground networks must be, m, not less than:

To the water supply - 1;

Domestic sewerage - 1;

Drainage and rainwater drainage - 1;

Gas pipelines of low, medium, high pressure - 0.5;

Power cables up to 100 kV and communication cables - 1;

Heating networks and common collectors – 2.

Laying two or more gas pipelines in one trench is allowed at the same or different levels (steps). The distances between gas pipelines must be sufficient for installation and repair of pipelines, but not less than 0.4 m for pipes with a diameter of up to 300 mm.

Vertical clear distances when crossing underground gas pipelines of all pressures with other underground structures and communications must be, m, not less than:

Water supply, sewerage, drainage, telephone sewerage, etc. - 0.15;

Heating network channel - 0.2;

Electrical cable, telephone armored cable - 0.5;

Oil-filled electric cable (110–220 kV) - 1.

Rice. 33. Scheme of gas supply to an industrial enterprise from medium-pressure urban gas pipelines.

1 – medium (or high) pressure city gas distribution pipeline; 2 – gas pipeline entry; 3 – valve with compensator in a deep well; 4 – underground inter-shop gas pipelines of medium or high pressure; 5 – hydraulic fracturing and central gas flow measurement point; 6 – underground inter-shop gas pipelines of medium pressure; 7 – tap; 8 – above-ground gas pipelines laid along the wall of the building; 9 – cabinet main control unit (CVD); 10 – valve with compensator in a deep well (shop shut-off device); 11 – fitting with a tap and plug for taking a sample; 12 – purge gas pipeline; 13 – disconnecting device (valve) at the entrance to the workshop; 14 – tap in a shallow well; 15 – above-ground inter-shop gas pipelines laid along columns; 16 – U-shaped compensator; 17 – valve on an overhead gas pipeline with a platform and ladder for servicing it; 18 – intra-shop GRU.

Reducing the distance between the gas pipeline and the electrical cable or armored communication cable is possible if they are laid in cases, and the clear distance between the gas pipeline and the wall of the case must be, m, not less than: when laying the electric cable - 0.25; armored communication cable - 0.15, and the ends of the case should extend 1 m on both sides from the walls of the gas pipeline being crossed.

Overhead gas pipelines. These gas pipelines are more accessible to the supervision of maintenance personnel, are less susceptible to deformation, and allow you to quickly eliminate possible problems and carry out repair work without disconnecting consumers. Low and medium pressure gas pipelines are allowed to be laid on the external walls of residential and public buildings of at least IV degree of fire resistance and on separate fireproof supports, and low pressure gas pipelines with a nominal pipe diameter of up to 50 mm - along the walls of residential buildings.

Overhead gas pipelines should be designed taking into account the compensation of longitudinal deformations and, if necessary, when self-compensation is not ensured, the installation of compensators (not stuffing boxes) should be provided. The height of the gas pipeline should be selected taking into account the provision of its inspection and repair. Flanged or threaded connections on gas pipelines should not be provided under window openings and balconies of buildings. Gas pipelines laid along the outer walls of buildings, overpasses, supports, as well as risers at the exit from the ground, if necessary, must be protected from mechanical damage. Gas pipelines must have a slope of at least 0.003; condensate removal devices must be installed at the lowest points. Thermal insulation must be provided for these gas pipelines.

The minimum horizontal clear distances from above-ground gas pipelines laid on supports to residential and public buildings must be at least 2 m. Clear distances between jointly laid and intersecting above-ground gas pipelines and pipelines for other purposes must be accepted for a gas pipeline diameter of up to 300 mm, at least diameter of the gas pipeline, but not less than 100 mm. The distances between the supports of above-ground gas pipelines should be determined in accordance with the requirements of the current “Guidelines for the calculation of steel pipelines for various purposes.”

Disabling devices. On gas pipelines, it is planned to install disconnecting devices at gas pipeline inputs into individual buildings or their groups (two adjacent buildings or more), as well as in front of external (open) gas consuming installations. On underground gas pipelines they should be installed in shallow wells with compensators. On gas pipelines with a nominal bore of less than 100 mm, U-shaped compensators should be used predominantly. When steel fittings are connected to gas pipelines by welding, compensators are not installed.

The installation of shut-off devices at the inputs of low-pressure gas pipelines should, as a rule, be provided outside the building. For fittings located at a height of more than 2.2 m, platforms made of non-combustible materials with ladders or a remote drive should be provided. To service fittings that are rarely used, it is permissible to use a portable ladder.

When laying two or more gas pipelines in one trench, the installed shut-off valves must be offset relative to each other at a distance that ensures ease of maintenance and repair.

Gas pipelines indoors. Indoors, gas pipelines are laid openly along the walls, parallel to the floor (ceiling). The length of LPG gas pipelines from risers to gas appliances is minimal. Pipes are not allowed to cross living rooms, and when passing through walls, smoke and ventilation ducts are not allowed. When attaching gas pipelines to walls, it is necessary to maintain distances that ensure the possibility of inspecting and repairing gas pipelines and the shut-off valves installed on them. Installation of taps with a stop nut towards the wall is unacceptable.

The relative location of gas pipelines and electrical wiring inside buildings must satisfy the following requirements:

A distance of at least 10 cm must be maintained from an openly laid electrical wire (electrical wire) to the wall of the gas pipeline (it can be reduced to 5 cm when laying electrical wires in tubes);

at the intersection of the gas pipeline with an openly laid electrical wire, the latter must be enclosed in a rubber or ebonite tube protruding 10 cm from each side of the gas pipeline;

When a hidden electrical wire is laid, a distance of at least 5 cm must be maintained from the wall of the gas pipeline, counting to the edge of the sealed furrow.

Where the gas pipeline intersects with other pipelines (water supply, sewerage), their pipes should not touch. To turn off the gas, in addition to the tap on each riser, taps are installed at the entrance to the apartment, in the stairwell (at the stair riser), on the branch from the riser to the appliances in the kitchen and in front of each appliance. If the riser is located in the kitchen and only one gas appliance is installed in the apartment (stove without a meter), a shut-off valve at the outlet from the riser may not be installed. Gas pipelines laid indoors must be made of steel pipes. Pipe connections should usually be made by welding. Threaded and flanged connections are allowed only in places where shut-off valves and gas appliances are installed. Detachable connections of gas pipelines must be accessible for inspection and repair.

The laying of gas pipelines inside buildings and structures should be open. In the premises of consumer service enterprises, public catering and laboratories, it is allowed to lay gas supply pipelines to individual units, gas appliances in a concrete floor, followed by sealing the pipes with cement mortar. In this case, anti-corrosion insulation must be provided for the pipes. Where the gas pipeline enters and exits the floor, cases must be provided that protrude above them by at least 3 cm.

Fundamentally, the design of gas pipelines for supplying industrial and municipal enterprises with increased gas consumption is distinguished by the possibility of using medium pressure. According to the “Safety Rules in the Gas Industry” and SNiP 42-01-02, inter-shop gas pipelines at industrial enterprises can be either underground or aboveground. The choice of method for laying inter-shop gas pipelines depends on the degree of saturation of the territory with underground communications, the type of soil and coatings, the nature of construction structures and buildings, the location of the shops consuming gas, and technical and economic considerations. As a rule, enterprises give preference to above-ground laying of inter-shop gas pipelines.

Gas supply schemes for enterprises, like the methods of laying gas pipelines, are varied. When choosing a scheme, it is necessary to be guided by technical and economic requirements, as well as reliability and safety requirements: ensuring the necessary parameters of combustible gas (pressure and flow) in front of the gas burners of heating units; minimum capital and metal investments (minimum diameters and lengths of gas pipelines, number of hydraulic fracturing stations and gas distribution units); ensuring reliable and safe construction, installation, commissioning and operation.

Rice. 34. Scheme of gas supply to the enterprise from the city low-pressure gas pipeline.

1 – city low-pressure gas distribution pipeline; 2 – gas pipeline entry; 3 – valve with compensator in a deep well; 4 – hydraulic valve; 5 – purge gas pipeline; 6 – fitting with a tap and plug for taking a sample; 7 – underground inter-shop (yard) low-pressure gas pipelines; 8 – tap in a shallow well.

Depending on the gas flow and pressure, the operating mode of heating units, the territorial location of gas consumers at the enterprise and technical and economic indicators, and taking into account the practice of design and operation, several standard gas supply schemes for industrial and municipal enterprises are distinguished.

Municipal enterprises with relatively low gas consumption and heating units operating on low-pressure gas (factory kitchens, canteens, built-in heating boiler houses with sectional boilers, etc.), as a rule, are connected to city low-pressure gas pipelines or tank farms (for complexes autonomous gas supply with propane-butane mixtures) (Fig. 33).

The gas supply circuit consists of a gas pipeline input with a common shut-off device, inter-shop gas pipelines with shut-off devices in front of each shop, purge gas pipelines and elements such as control tubes, control conductors, condensate collectors (for wet gases), compensators, etc.

A general shut-off device (valve) is installed at the gas pipeline inlet. It is designed to shut off the gas supply during repairs or failure of the gas supply system. Purge gas pipelines are designed to remove air and the gas-air mixture and fill the system with clean gas during the initial and subsequent (after repairs of inter-shop gas pipelines or long-term shutdown of the system) startups. To determine the quality of the purge, a fitting with a tap is installed on the purge gas pipeline to take a sample of the medium, the composition of which can be determined on a gas analyzer.

In the gas supply scheme under consideration, underground laying of gas pipelines is conventionally accepted. The diagram does not show condensate collectors: for centralized gas supply, dried natural gas is used, and when using wet flammable gases, gas pipelines are laid with a slope and condensate collectors are installed at low points in the system.

Medium and large industrial enterprises are connected to medium or high pressure urban gas distribution pipelines (Fig. 34). As an example, it is assumed that in shops 2 and 3 heating units operate on medium pressure gas (the gas pressure in front of the burners of the units is assumed to be equal), and in shops 1 and 4 - on low pressure gas. After the general shut-off device, a gas control point (GRP) is installed on the inter-shop gas pipeline of the initial gas pressure, designed to reduce the gas pressure from high or medium to the medium pressure required for the heating units of shops 2 and 3, taking into account pressure losses. A central gas flow measurement point is installed in the gas distribution center building, intended for business settlements between the enterprise and the supplier. In shops 1 and 4, a gas control unit (GRU) is additionally installed to use low-pressure gas.

For inter-shop gas pipelines, a mixed laying scheme has been adopted - underground and aboveground. Aboveground gas pipelines can be laid along the external walls and fireproof coatings of industrial buildings with production facilities classified as fire hazard categories B, D and E, as well as along free-standing columns (supports) and overpasses made of fireproof materials. Important note: high-pressure gas pipelines can be laid along the walls of industrial buildings only above the windows of the upper floors or along blank walls.

The diameters of gas pipelines are determined by hydraulic calculations at maximum gas flow, taking into account the future growth in consumption associated with the development of the enterprise and acceptable pressure losses. All underground steel gas pipelines are protected from corrosion caused by soil and stray electrical currents. For this purpose, both passive and active protection measures are used.

Features of autonomous gas supply systems using low and medium pressures include the predominant use of burners with forced air supply, optimized for operation on low pressure gas. In this case, there is no need to reduce the pressure, as is necessary to do when supplied from centralized natural gas pipelines (the pressure reduction in the regulators reaches 0.1–0.2 MPa).

Table 3.

Gas pressure in supply lines for different consumers

Gas consumers	Gas pressure, MPa
Industrial buildings in which the gas pressure is determined by production requirements	1,2
Other industrial buildings	0,6
Domestic buildings of industrial enterprises, separate, attached to industrial buildings and built into these buildings	0,3
Administrative buildings	0,005
Boiler houses - free-standing on the territory of industrial enterprises - free-standing on the territory of settlements - attached, built-in and roof-top industrial buildings - attached, built-in and roof-top public, administrative and domestic buildings - attached, built-in and roof-top residential buildings	1,2 0,6 0,6 0,3 0,005
Public buildings (except for buildings in which the installation of gas equipment is not permitted by the requirements of SNiP 2.08.02) and warehouses	0,005
Residential buildings	0,003

Table 4.

Gas pressure in above-ground gas pipelines depending on the class of consumers and location features

Placement of above-ground gas pipelines	Gas pressure in the gas pipeline, MPa, no more
1. On free-standing supports, columns, overpasses and shelves	1.2 (for natural gas); 1.6 (for LPG)
2. Boiler rooms, industrial buildings with premises of categories B, G and D and State Tax Service (GNP) buildings, public and domestic buildings for industrial purposes, as well as built-in, attached and roof boiler rooms to them: a) on the walls and roofs of buildings of I and II degrees fire resistance class fire hazard C0 (according to SNiP 21-01) II degree of fire resistance class C1 and III degree of fire resistance class C0 b) on the walls of buildings III degree of fire resistance class C1, IV degree of fire resistance class C0 IV degree of fire resistance classes C1 and C2	1,2* 0,6* 0,3* 0,005
3. Residential, administrative, public and domestic buildings, as well as built-in, attached and roof boiler rooms to them - along the walls of buildings of all degrees of fire resistance - in cases where the SHRP is placed on the external walls of buildings (only up to the SHRP)	0,005 0,3

Laying a gas pipeline is a technically complex and responsible process that must be carried out by trained, qualified specialists, and only according to strictly established rules.

Types of gas pipelines

Gas pipelines are classified depending on pressure and location.

The pressure level can be:

• low pressure (up to 5 kPa);
• medium pressure (up to 0.3 MPa);
• high pressure (up to 1.2 MPa).

Gas pipelines with medium and high pressure are intended to supply gas to industrial production enterprises and gas distribution stations, so it is advisable to build them as a resource for large-scale production.

A low-pressure gas pipeline is used to supply gas directly to homes, so it is necessary to build it for populated areas, residential and public facilities.

By location they can be of the following type:

• underground;
• ground;
• external;
• internal.

Each type has its own characteristics and nuances. The choice of method for laying a gas pipeline depends on many indicators, for example, the characteristic properties of the soil and climatic conditions.

Gas pipeline communications are divided into:

• gas pipelines of distribution networks.

Main gas pipelines. Designed for gas delivery over long distances. At certain distances, gas compressor stations must be installed, which are designed to maintain pressure.

Gas distribution networks designed to supply gas from gas distribution stations to consumers.

Main components of the gas pipeline

Blue fuel is supplied through gas pipelines through special distribution stations, where automatic regulator valves must reduce the pressure and ensure its stable required level.

Gas pipeline networks consist of:

• internal highway;
• external highways of populated areas;
• automated control systems;
• electrochemical protection means;
• regulatory points.

There may be several options for installing a gas pipeline. The choice of installation method depends on many parameters and the specific case. Climatic conditions, site development and other parameters are taken into account.

Laying underground gas pipelines

This type of installation involves laying a gas pipeline underground. As a rule, such installation requires pre-prepared dug trenches. In this case, the depth of the dug canal and communication wiring should be taken into account according to the project; it should be at least 0.8 m. When choosing a location, it is necessary to take into account the distance to buildings, structures and other communications (sewage, heating network). It is undesirable to lay an underground gas pipeline near trees, since their root system can complicate its repair and operation. When laying pipes and assembling a gas device in this way, the following points should be taken into account:

• the gap between the gas pipeline and other underground utilities must be at least 0.2 m;
• at intersections with communication collectors, gas pipes must be pulled in cases;
• the gas main is located above other utility networks;
• cases must be placed beyond the intersection at a distance of at least 0.2 m;
• The ends of the cases are treated using waterproofing materials.

Another method of underground installation is the trenchless installation option. This option is the least expensive. The advantages of the trenchless method of laying a gas pipeline are as follows:

• reduces the financial costs of installing a gas pipeline;
• reduces installation time.

The underground method of laying a gas pipeline is the safest, but such installation is more expensive.

Laying of above-ground gas pipelines

The cost of laying an above-ground gas pipeline is significantly lower than the underground method. With this installation option, the pipes are laid on special supports. Aboveground gas lines are convenient for inspection and repair, and are less dangerous in the event of a gas leak and in terms of gas entering the premises. It should be taken into account that the pipes must be maximally protected from deformation and damage as a result of corrosion, temperature changes, and mechanical loads of various origins. The type of protection is selected depending on the climate conditions in a particular region.

When laying on land, constant security monitoring is required, which helps prevent the possibility of unauthorized connection to the highway. On this side, the reliability of an above-ground gas pipeline is lower compared to underground pipe laying. For laying overhead gas pipelines, there are certain rules that must be followed.

First of all, certain distances above the ground and between supports are established.

The distance above the ground should be:

• in places where people pass by, at least 2.2 m;
• 5 m – above highways;
• at least 7.1–7.3 m above tram and trolleybus tracks.

The gap between the supports depends on the diameter of the pipe:

• the maximum permissible distance is 100 m if the pipe diameter does not exceed 30 cm;
• 200 m with a diameter of up to 60 cm;
• 300 m over 60 cm.

The thickness of the pipe walls is taken into account; it must be at least 2 mm.

Laying external and internal gas pipelines

- a system of pipes and communications located inside buildings. In this case, the pipe routing should not be covered with any additional covers or hidden in the wall; there should be free access for regular preventive inspection and repair work.

When gas communications are located externally, access to it by strangers should be limited as much as possible. To achieve this, the structural elements are mounted at a sufficiently high height. The fixation of pipes to the facade walls must be reliable to prevent the gas pipe from falling.

Advantages of using polyethylene pipes

Gas in the systems can be supplied through steel or polyethylene lines. Steel pipes are used for all types of gas pipelines, polyethylene pipes are used only for underground installation. Polyethylene pipes are in great demand for gasification in the construction market, as they provide a lower budget for the costs required for the construction, maintenance and repair of the gas pipeline.

Polyethylene pipes have a number of advantages compared to other materials, namely:

• Not exposed to aggressive environments, temperature changes, or corrosion.
• Provide ease of installation (if necessary, pipe fitting, cutting).
• There is no need to create additional protection against the occurrence of a chemical reaction with any substances.
• The polymer is not a conductor of electric current, therefore, it protects against “stray” current in the soil, which can cause an accident.
• The inner walls of polyethylene pipes are absolutely smooth, which increases the throughput of the gas pipeline, preventing clogging.
• They have an affordable price, lower compared to analogues.
• The weight of polymer pipes is much less, which simplifies the process of transportation, storage and installation.
• They have a long service life, up to 50 years.

Limitations of the use of polymer pipes

Despite the great demand and advantages of polymer pipes, there are restrictions on their use, namely the following:

• In climatic regions where the ambient temperature can drop to -45 degrees Celsius.
• When transporting liquefied gas.
• In areas where the amplitude of an earthquake can exceed seven points.
• In case of installation of above-ground gas pipelines.
• When a gas structure passes over automobile or railway tracks.
• When laying gas pipelines transporting external and internal gas.

In cases where it is impossible to install polymer pipes, steel pipes are used. If all operating requirements are met, they are durable and have a long service life. Steel pipes can be used for any method of laying gas pipelines.

Laying technology and assembly rules

Laying gas pipelines is a difficult and labor-intensive process that is carried out in stages and includes several stages. A preparatory stage is required, including the development of a gas pipeline project.

The project should be developed only by qualified specialists; installation will be carried out on its basis in the future. The project must take into account the features of the landscape and soil of the area where installation work will be carried out, as well as the climatic conditions of the area.

The second stage includes the installation of gas pipelines. Next, commissioning work is carried out.

The final stage is monitoring the installed gas pipeline. It is necessary to test it for strength and check the sealing of all structural elements. Everything can be carried out only after installing all the auxiliary parts.

The gas pipeline is an explosive structure, so no construction should be carried out in the immediate vicinity. For this purpose, special posts are used that mark the security zone. The size of the security zone depends on the type of gas pipeline. Appropriate warning signs are installed in required places.

Main conclusions:

• A gas pipeline is a structure that creates a danger.
• Installation requires strict adherence to safety regulations, violation of which can lead to dangerous consequences.
• Prepare the necessary technical documentation for permitting and installation of gas equipment.
• Only specially trained people should carry out the design and installation process.
• It is important to comply with all requirements for materials and components of the gas pipeline.

Finally

Gas consumption in the modern world is growing. This is due to the relatively low cost, fairly high speed, and high degree of environmental friendliness of the product. Gas is a popular type of fuel, which leads to an expansion in the construction of gas pipelines.

It should be taken into account that gas, as a flammable substance, poses a certain danger. Therefore, the installation of the gas pipeline must be carried out in accordance with the rules and safety instructions. Strict adherence to installation rules will prevent gas leakage and the possibility of explosion.

INTERNAL GAS SUPPLY DEVICES

GENERAL INSTRUCTIONS

6.1. The provisions of this section apply to design of gas pipelines and gas equipment, placed inside buildings and structures for various purposes.

Possibility of installing gas equipment and laying gas pipelines in specific buildings should be determined in accordance with the building codes and regulations for the design of the relevant buildings.
LAYING GAS PIPELINES

6.2. Gas pipelines laid inside buildings and structures should be made of steel pipes that meet the requirements of Section. eleven.

To connect mobile units, portable gas burners, gas appliances, instrumentation and automation devices, it is allowed to provide rubber and rubber-fabric hoses. When choosing hoses, one should take into account their resistance to the transported gas at a given pressure and temperature.

6.3. Pipe connections should usually be made by welding. Detachable (threaded and flanged) connections may be provided only in places where shut-off valves, gas appliances, instrumentation, pressure regulators and other equipment are installed.

The installation of detachable connections of gas pipelines should be provided in places accessible for inspection and repair.

6.4. The laying of gas pipelines inside buildings and structures should, as a rule, be open. It is allowed to provide for the hidden installation of gas pipelines (except for LPG gas pipelines and gas pipelines inside residential buildings and public buildings of a non-industrial nature) in the grooves of the walls, covered with easily removable shields that have holes for ventilation.

6.5. In the production premises of industrial enterprises, including boiler houses, buildings of consumer service enterprises for industrial purposes and public catering, as well as laboratories, it is allowed to lay gas supply pipelines to individual units and gas appliances in the floors of a monolithic structure, followed by sealing the pipes with cement mortar. In this case, it is necessary to provide for painting the pipes with oil or nitro-enamel waterproof paints.

At the points where the gas pipeline enters and exits the floor, cases should be provided, the ends of which should protrude above the floor by at least 3 cm.

6.6. In the production premises of industrial enterprises, it is allowed to lay gas pipelines in the floor in channels covered with sand and covered with slabs.

The design of the ducts must exclude the possibility of gas spreading under the floor.

Laying gas pipelines in channels is not allowed in places where, due to production conditions, substances causing corrosion of pipes may enter the channels.

6.7. Channels intended for laying gas pipelines, as a rule, should not intersect with other channels.

If it is necessary to cross channels, provision should be made for the installation of sealing bridges and the laying of gas pipelines in cases made of steel pipes. The ends of the cases must be extended beyond the jumpers by 30 cm in both directions.

6.8. When laid together with other pipelines on common supports, gas pipelines should be placed above them at a distance that ensures ease of inspection and repair.

6.9. The laying of gas pipelines in transit through industrial premises where gas is not used is allowed for low and medium pressure gas pipelines, provided that no fittings are installed on the gas pipeline and unhindered 24-hour access to these premises is provided for personnel servicing the gas pipeline.

6.10. It is not allowed to provide for the laying of gas pipelines in premises classified as explosion and fire hazard categories A and B; in explosive zones of all premises; in basements; in warehouse buildings of explosive and flammable materials; in the premises of substations and distribution devices; through ventilation chambers, shafts and channels; elevator shafts; waste disposal rooms; chimneys; through rooms where the gas pipeline may be subject to corrosion, as well as in places of possible exposure to aggressive substances and in places where gas pipelines may be washed by hot combustion products or come into contact with heated or molten metal.

6.11. For internal gas pipelines experiencing temperature effects, it is necessary to provide for the possibility of compensating for temperature deformations.

6.12. For gas pipelines transporting wet gas and laid in rooms where the air temperature may be below 3 °C, thermal insulation made of non-combustible materials should be provided.

6.13. Shut-off devices on gas pipelines in production premises of industrial and agricultural enterprises, industrial consumer service enterprises should be provided with:

at the gas pipeline entrance indoors;

on branches to each unit;

in front of burners and igniters;

on purge pipelines, at places where they are connected to gas pipelines.

If there is a gas meter or gas control unit inside the room, located at a distance of no more than 10 m from the gas pipeline entry point, the shut-off device at the input is considered to be a valve or tap in front of the gas pipeline or meter.

Installation of fittings on gas pipelines laid in channels, in concrete floors or in wall grooves is not allowed.

6.14.* The need to meter gas consumption and the choice of metering system at gas supply facilities must be determined in accordance with the instructions of the “Rules for the use of gas in the national economy” approved by the Ministry of Gas Industry and the “General Provisions on the Procedure for Accounting and Control of Fuel, Electrical and Heat Energy Consumption for Industrial , transport, agricultural and public utility enterprises and organizations” approved by the State Committee for Science and Technology, the State Planning Committee of the USSR, and the State Standard.

According to the decision of the executive authorities of the constituent entities of the Russian Federation on the procedure for recording gas consumption by consumers and regulating gas prices in gasified residential buildings, as well as during gasification of greenhouses, bathhouses and other household buildings, it must be possible to record the gas consumption of each subscriber by installing it on the gas pipeline (in apartment, individual house) gas consumption meter - meter.

6.15. Gas flow metering devices should be placed in gas distribution centers or gasified premises. It is allowed to place gas flow metering devices in other rooms of at least II degree of fire resistance that have exhaust ventilation.

No more than two gas meters can be installed in parallel on one gas pipeline.

6.16. The laying of gas pipelines in residential buildings should be provided for non-residential premises.

In existing and reconstructed residential buildings, it is allowed to provide for the transit laying of low-pressure gas pipelines through living rooms if no other installation is possible. Transit gas pipelines within residential premises should not have threaded connections or fittings.

It is not allowed to provide gas pipeline risers in living rooms and sanitary facilities.

6.17.* The installation of shut-off devices on gas pipelines laid in residential buildings and public buildings (with the exception of public catering establishments and consumer service enterprises of an industrial nature) should provide for:

to disconnect risers serving more than five floors;

in front of the meters (if a disconnecting device at the input cannot be used to turn off the meter);

in front of each gas appliance, stove or installation;

on branches to heating stoves or appliances in accordance with the requirements of clause 6.46.

On gas supply pipelines to cooking boilers, restaurant stoves, heating stoves and other similar equipment, it is necessary to install two shut-off devices in series: one to turn off the device (equipment) as a whole, the other to turn off the burners.

On gas supply pipelines to gas appliances that have a shut-off device in front of the burners in their design (gas stoves, water heaters, stove burners, etc.), it is necessary to install one shut-off device.

The need to install devices for disconnecting risers (entrances) of 5-story or less residential buildings is decided by the design organization depending on local specific conditions, including the number of floors of buildings and the number of apartments to be disconnected in the event of emergency and other work.

Devices provided for disconnecting risers (entrances) should be installed, whenever possible, outside the building.

6.18. The distance from gas pipelines laid openly and in the floor indoors to building structures, process equipment and pipelines for other purposes should be taken from the condition of ensuring the possibility of installation, inspection and repair of gas pipelines and fittings installed on them, while gas pipelines should not cross ventilation grilles, window and doorways. In industrial premises, it is allowed to cross light openings filled with glass blocks, as well as lay a gas pipeline along the sashes of non-opening windows.

6.19. The minimum clear distances between a gas pipeline laid along the wall of a building and communication and wired broadcasting structures should be taken in accordance with the “Safety Rules for Work on Cable Communication and Wired Broadcasting Lines” approved by the USSR Ministry of Communications in the prescribed manner.

6.20. The distances between gas pipelines and electrical utilities located indoors, at points of convergence and intersection, should be taken in accordance with the PUE.

6.21. The laying of gas pipelines in places where people pass should be provided at a height of at least 2.2 m from the floor to the bottom of the gas pipeline, and if there is thermal insulation - to the bottom of the insulation.

6.22.* Fastening of openly laid gas pipelines to walls, columns and ceilings inside buildings, frames of boilers and other production units should be provided using brackets, clamps, hooks or hangers, etc. at a distance that allows for inspection and repair of the gas pipeline and the fittings installed on it.

The distance between the support fastenings of gas pipelines should be determined in accordance with the requirements of SNiP 2.04.12-86.

6.23. The laying of gas pipelines transporting wet gas (except for the vapor phase of low-pressure LPG) should be provided with a slope of at least 3 o/oo.

If there is a gas meter, the slope of the gas pipeline should be provided from the meter.

6.24. Vertical gas pipelines at intersections of building structures should be laid in cases. The space between the gas pipeline and the case must be sealed with tarred tow, rubber bushings or other elastic material. The end of the casing must protrude above the floor by at least 3 cm, and its diameter must be taken from the condition that the annular gap between the gas pipeline and the casing is at least 5 mm for gas pipelines with a nominal diameter of no more than 32 mm and at least 10 mm for gas pipelines of larger diameter.

6.25. Internal gas pipelines, including those laid in channels, should be painted. For painting, waterproof paints and varnishes should be used.

6.26. Gas appliances and gas burners should be connected to gas pipelines, as a rule, with a rigid connection.

Connection to the gas pipeline of gas appliances, laboratory burners, as well as portable and mobile gas-burning devices and units installed in the workshops of industrial enterprises may be provided after the shut-off valve with rubber-fabric hoses. Rubber-fabric hoses for connecting household gas appliances and laboratory burners should not have butt joints.

6.27. On gas pipelines of industrial (including boiler houses), agricultural enterprises, consumer service enterprises of a production nature, purge pipelines should be provided from the sections of the gas pipeline that are most remote from the point of entry, as well as from bends to each unit before the last shut-off device along the gas flow.

It is allowed to combine purge pipelines from gas pipelines with the same gas pressure, with the exception of purge pipelines for gases with a density greater than that of air.

The diameter of the purge pipeline should be at least 20 mm.

After the shut-off device, a fitting with a tap for sampling should be provided on the purge pipeline, if a fitting for connecting an igniter cannot be used for this purpose.

In some cases (for example, for cutting and welding stations, small industrial furnaces) with a supply gas pipeline with a diameter of no more than 32 mm, it is allowed to install a shut-off device with a blind fitting instead of purge pipelines.

6.28. The distance from the end sections of the purge pipelines to the intake ventilation devices must be at least 3 m.

When the building is located outside the lightning protection zone, the outlets of the purge pipelines should be grounded.
GAS SUPPLY TO RESIDENTIAL BUILDINGS

6.29. The installation of gas stoves in residential buildings should be provided in kitchens with a height of at least 2.2 m, having a window with a window (transom), an exhaust ventilation duct and natural lighting.

In this case, the internal volume of kitchen premises must be, m3, not less than:

for gas stove with 2 burners 8

« « « « 3 « 12

« « « « 4 « 15

6.30. In existing residential buildings, it is allowed to install gas stoves:

in kitchen premises with a height of at least 2.2 m and a volume not less than that specified in clause 6.29 in the absence of a ventilation duct and it is impossible to use chimneys as such a duct, but if there is a window in the room with a window or transom in the upper part of the window;

in private corridors, if there is a window in the corridor with a window or transom in the upper part of the window, the passage between the slab and the opposite wall must be at least 1 m wide, the walls and ceilings of the corridors made of flammable materials must be plastered, and the living quarters must be separated from corridor with dense partitions and a door;

in kitchens with sloping ceilings with a height in the middle part of at least 2 m, the installation of gas equipment should be provided in that part of the kitchen where the height is at least 2.2 m.

6.31.* In existing residential buildings owned by citizens as personal property, it is allowed to install gas stoves in premises that meet the requirements of paragraphs. 6.29 or 6.30, but having a height of less than 2.2 m up to 2 m inclusive, if these premises have a volume of at least 1.25 times the standard. Moreover, in houses that do not have a dedicated kitchen, the volume of the room where the gas stove is installed must be twice as large as specified in clause 6.29.

If it is impossible to meet these requirements, the installation of gas stoves in such premises may be allowed on a case-by-case basis with the approval of the local sanitary inspection authority.

6.32.* The possibility of installing gas stoves, heating and other devices in buildings located outside a residential building is decided by the design organization and operational organization of the gas industry, taking into account specific local conditions, including the availability of gas for these purposes. At the same time, the premises in which the installation of gas appliances is planned must comply with the requirements for the premises of residential buildings where the placement of such appliances is allowed.

6.33. Wooden unplastered walls and walls made of other combustible materials in places where the slabs are installed should be insulated with non-combustible materials: plaster, roofing steel on an asbestos sheet with a thickness of at least 3 mm, etc. The insulation should protrude beyond the dimensions of the slab by 10 cm on each side and at least 80 cm above.

The distance from the stove to the walls of the room insulated with non-combustible materials must be at least 7 cm; the distance between the slab and the opposite wall must be at least 1 m.

6.34. For hot water supply, instantaneous or capacitive gas water heaters should be provided, and for heating - capacitive gas water heaters, small heating boilers or other heating devices designed to operate on gas fuel.

The number of floors of residential buildings in which the installation of the specified gas appliances and apparatus is permitted should be taken in accordance with SNiP 2.08.01-89.

6.35. It is allowed to convert small-sized (small-sized) factory-made heating boilers intended for solid or liquid fuels to gas fuel.

Heating installations converted to gas fuel must be equipped with gas burner devices with automatic safety in accordance with the requirements provided for in Section. eleven.

In one room it is not allowed to install more than two capacitive water heaters or two small heating boilers or two other heating devices.

6.36. The installation of chimneys must comply with the requirements of SNiP 2.04.05-91* as for heating stoves. When deciding on the possibility of connecting gas appliances to chimneys, it is permissible to be guided by the data given in reference Appendix 6.

6.37.* Installation of water heaters, heating boilers and heating devices should be provided in kitchens and non-residential premises intended for their placement and meeting the requirements of paragraphs. 6.42* and 6.43. Installation of these devices in bathrooms is not permitted. The issue of the need to move gas water heaters from bathrooms, in which they were placed in accordance with previously existing standards, to kitchens or other non-residential premises of a residential building during the reconstruction of a house or gas supply system, should be decided on a case-by-case basis by the design organization in agreement with local operating organizations gas industry.

In existing residential buildings, it is allowed to provide for the installation of gas heating appliances and heating devices in corridors for individual use that meet the requirements of paragraphs. 6.42* and 6.43.

The distance from the protruding parts of gas burners or fittings to the opposite wall must be at least 1 m.

6.38. Installation of gas instantaneous water heaters should be provided on walls made of non-combustible materials at a distance of at least 2 cm from the wall (including from the side wall).

If there are no walls made of non-combustible materials in the room, it is allowed to install a flow-through water heater on plastered, as well as on walls lined with non-combustible or difficult-to-combustible materials at a distance of at least 3 cm from the wall.

The surface of fire-resistant walls should be insulated with roofing steel over an asbestos sheet with a thickness of at least 3 mm. The insulation should protrude 10 cm beyond the dimensions of the water heater body.

6.39. The installation of gas heating boilers, heating devices and capacitive gas water heaters should be provided near walls made of non-combustible materials at a distance of at least 10 cm from the wall.

If there are no walls made of non-combustible materials in the room, it is allowed to install the above-mentioned heating devices near the walls, protected in accordance with the instructions of clause 6.38, at a distance of at least 10 cm from the wall.

6.40. The horizontal clear distance between the protruding parts of the instantaneous water heater and the gas stove should be at least 10 cm.

6.41.* When installing a gas stove and instantaneous water heater in the kitchen, the volume of the kitchen should be taken in accordance with clause 6.29.

When installing a gas stove and a cylinder water heater, a gas stove and a heating boiler or heating device in the kitchen, as well as a gas stove with built-in devices for heating water (heating, hot water supply), the volume of the kitchen must be 6 m3 greater than the volume provided for in clause 6.29.

6.42.* The room intended to accommodate a gas water heater, as well as a heating boiler or heating apparatus, the combustion products of which are discharged into the chimney, must have a height of at least 2 m. The volume of the room must be at least 7.5 m3 when installing one device and not less than 13.5 m3 when installing two heating devices.

6.43. The kitchen or room where boilers, appliances and gas water heaters are installed must have a ventilation duct. For air flow, a grille or gap between the door and the floor with a clear cross-section of at least 0.02 m2 should be provided at the bottom of the door or wall opening into the adjacent room.

6.44.* It is not allowed to place all gas appliances in the basement floors (basements), and for LPG gas supply - in the basement and ground floors of buildings for any purpose.

Note. The requirements of this paragraph do not apply to residential buildings owned by citizens as personal property if the basements of these houses have natural light and their gas supply is from natural gas.

6.45. It is allowed to convert heating and heating-cooking furnaces to gas fuel, provided that:

stoves, smoke and ventilation ducts meet the requirements of departmental standards for the construction of heating stoves converted to gas fuel, approved in the prescribed manner;

gas burners installed in the furnaces of heating and heating-cooking furnaces are equipped with automatic safety systems in accordance with the requirements of GOST 16569-86.

6.46. The fireboxes of gasified stoves should be provided, as a rule, on the side of the corridor or other non-residential (non-office) premises.

If it is impossible to meet the specified requirement, it is allowed to provide fireboxes for gasified stoves on the side of residential (office) premises. In this case, the gas supply to the furnaces should be provided by independent branches, on which, at the point of connection to the gas pipeline, a shut-off device should be installed outside the above premises.

The rooms into which the fireboxes of gasified heating and heating-cooking stoves open must have an exhaust ventilation duct or a window with a window, or a door opening onto a non-residential premises or vestibule. A passage at least 1 m wide must be provided in front of the furnace.

6.47. For space heating, it is allowed to install gas fireplaces, air heaters and other factory-made appliances with combustion products discharged into the chimney. The gas burner devices of these devices must be equipped with automatic safety devices in accordance with the requirements provided for in Section. eleven.

The room in which a gas fireplace or heater is to be installed must have a window with a window or an exhaust ventilation duct.

When installing these devices, it is necessary to comply with the requirements provided for in clause 6.39.

6.48. The possibility of using and placement conditions for household gas appliances not specified in this section should be determined taking into account the purpose of the appliances, their thermal load, the need to remove combustion products and other parameters regulated by this section.

RESULTS OF COMBUSTION PRODUCTS

1. The removal of combustion products from household gas appliances, stoves and other household gas equipment, the design of which provides for the removal of combustion products into the chimney, should be provided from each appliance, unit or stove through a separate chimney.

In existing buildings, it is allowed to provide for the connection to one chimney of no more than two water heaters or heating stoves located on the same or different floors of the building, provided that combustion products are introduced into the chimney at different levels, no closer than 0.75 m from one another, or at the same level with a device in the chimney for cutting to a height of at least 0.75 m.

2. In existing buildings in the absence of chimneys, it is allowed to install attached chimneys.

3. It is allowed to connect to the chimney of a periodically operating heating stove a gas water heater used for hot water supply, or another gas appliance that does not operate continuously, provided that it operates at different times and the chimney cross-section is sufficient to remove combustion products from the connected appliance.

Connecting the smoke exhaust pipe of a gas appliance to the chimney revolutions of a heating stove is not allowed.

4. The cross-sectional area of ​​the chimney should not be less than the area of ​​the gas appliance pipe connected to the chimney. When connecting two appliances, stoves, etc. to a chimney, the cross-section of the chimney should be determined taking into account their simultaneous operation. The structural dimensions of chimneys must be determined by calculation.

5. Non-household gas appliances (restaurant stoves, cooking boilers, etc.) are allowed to be connected to both separate and common chimneys.

It is allowed to provide connecting smoke exhaust pipes common to several units.

The introduction of combustion products into a common chimney for several appliances should be provided at different levels or at the same level with the cutting device in accordance with paragraph 1.

The cross-sections of chimneys and connecting pipes must be determined by calculation based on the condition of simultaneous operation of all devices connected to the chimney.

6.* Chimneys must be vertical, without ledges. A slope of chimneys from the vertical is allowed up to 30° with a sideways deviation of up to 1 m, provided that the cross-sectional area of ​​the inclined sections of the chimney is not less than the cross-section of the vertical sections.

7. To remove combustion products from restaurant stoves and other non-household gas appliances, it is allowed to provide horizontal sections of chimneys with a total length of no more than 10 m.

It is allowed to provide chimneys in the ceiling with a fire-prevention cutting device for combustible ceiling structures.

8. Connection of gas water heaters and other gas appliances to chimneys should be provided with pipes made of roofing steel.

The total length of connecting pipe sections in new buildings should be no more than 3 m, in existing buildings - no more than 6 m.

The slope of the pipe should be at least 0.01 towards the gas appliance.

On smoke exhaust pipes it is allowed to provide no more than three turns with a radius of curvature no less than the diameter of the pipe.

Below the connection point of the smoke exhaust pipe from the appliance to the chimneys, a “pocket” device with a hatch for cleaning should be provided.

Smoke exhaust pipes laid through unheated rooms must, if necessary, be covered with thermal insulation.

9. The distance from the connecting smoke exhaust pipe to the ceiling or wall made of non-combustible materials should be at least 5 cm, to wooden plastered ceilings and walls - at least 25 cm. The specified distance can be reduced from 25 to 10 cm, provided that wooden plastered walls or ceilings are upholstered roofing steel on an asbestos sheet 3 mm thick. The upholstery should protrude beyond the dimensions of the chimney by 15 cm on each side.

10. When connecting one device to the chimney, as well as devices with draft stabilizers, dampers are not provided on the smoke exhaust pipes.

When connecting several appliances to a common chimney: restaurant stoves, boilers and other gas appliances that do not have draft stabilizers, dampers (dampers) with a hole with a diameter of at least 15 mm must be provided on the smoke exhaust pipes from the appliances.

11. Dampers installed on chimneys from boilers must have holes with a diameter of at least 50 mm.

12. Chimneys from gas appliances in buildings must be led out:

above the boundary of the wind support zone, but not less than 0.5 m above the roof ridge when they are located (counting horizontally) no further than 1.5 m from the roof ridge;

level with the roof ridge, if they are located at a distance of up to 3 m from the roof ridge;

not lower than a straight line drawn from the ridge down at an angle of 10° to the horizontal, when the pipes are located at a distance of more than 3 m from the ridge of the roof.

In all cases, the height of the pipe above the adjacent part of the roof must be at least 0.5 m, and for houses with a combined roof (flat roof) - at least 2.0 m.

The installation of umbrellas and deflectors on chimneys is not allowed.

13.* The removal of combustion products from gasified installations of industrial enterprises, boiler houses, and public service enterprises may be provided through steel chimneys.
APPENDIX 7*
Mandatory
SELECTION OF STEEL PIPES FOR GAS SUPPLY SYSTEMS

1. Steel pipes for gas supply systems with pressure up to 1.6 MPa (16 kgf/cm2), depending on the design temperature of the outside air of the construction area and the location of the gas pipeline relative to the ground surface, should be taken:

according to table 1* - for external above-ground gas pipelines laid in areas with a design temperature of external air not lower than minus 40 °C, as well as underground and internal gas pipelines that are not cooled to a temperature below minus 40 °C;

according to table 2 - for above-ground gas pipelines laid in areas with a design outside air temperature below minus 40 °C and underground gas pipelines that can be cooled to a temperature below minus 40 °C.

2. For gas supply systems, you should accept pipes made, as a rule, of ordinary quality carbon steel in accordance with GOST 380-88 and high-quality steel in accordance with GOST 1050-88.

3. For gas pipelines of the liquid phase of LPG, seamless pipes should, as a rule, be used.

It is allowed to use electric-welded pipes for these gas pipelines. In this case, pipes with a diameter of up to 50 mm must undergo 100% inspection of the weld using non-destructive methods, and pipes with a diameter of 50 mm or more must also undergo a tensile test of the weld.

Table 1*

Steel pipes for the construction of external above-ground gas pipelines laid in areas with a design temperature of outside air not lower than minus 40 °C, as well as underground and internal gas pipelines that are not cooled to a temperature below minus 40 °C

Standard or specification for pipes	Steel grade, steel standard	Pipe outer diameter (incl.), mm
1. Electric welded longitudinal welded GOST 10705-80 (group B) "Technically skies Slovenia " and GOST 10704-91 "Assortment"	VSt2sp, VSt3sp no less than 2nd category GOST 380-88; 10, 15, 20 GOST 1050-88
2. Electric welded TU 14-3-943-80	10 GOST 1050-88	219-530
3. Electric welded for main gas and oil pipelines (straight seam and spiral welded) GOST 20295-85	VSt3sp no less e 2nd category (K38) GOST 380-88; 10 ( K34 ), 15 (K38), 20 (K42) GOST 1050-88	According to GOST 20295-74
4. Electric welded straight-seam GOST 10706-76 (group B) “Technical requirements” and GOST 10704-91 “Assortment”	VSt2sp, VSt3sp not me not 2nd category GOST 380-88
5. Electros welded with a spiral seam GOST 8696-74 (group B)	VSt2sp, VSt3sp no less than 2nd category GOST 380-88
6. Seamless hot-deformed GOST 8731-87 (group B and D) “Technical requirements” and GOST 8732-78 “Assortment”	10, 20 GOST 1050-88
7. Seamless cold-deformed, heat-deformed GOST 8733-87 (gr Unit B and D) “Technical requirements” and GOST 8734-75 “Assortment”	10, 20 GOST 1050-88
8. Electric welded spiral welded TU 14-3-808-78	TU 14-3-808-78	530-820; 1020; 1220
9. Seamless hot-deformed according to TU 14-3-190-82 (only for thermal power plants)	10, 20 GOST 1050-88
Notes: 1. Pipes according to paragraphs. 6 and 7 follows when change like For example, for gas pipelines of the liquid phase of LPG. 2. Excluded. 3. For heat fishing elect Rostanz I'm working would be used from steel 20 in areas with a design temperature of up to minus 30 ° C

4.* Pipes in accordance with GOST 3262-75 may be used for the construction of external and internal low-pressure gas pipelines. Pipes in accordance with GOST 3262-75 with a nominal diameter of up to 32 mm inclusive. may be used for the construction of impulse gas pipelines with pressures up to 1.2 MPa (12 kgf/cm2) inclusive. In this case, bent sections of pulse gas pipelines must have a bend radius of at least 2De and the temperature of the pipe wall during operation should not be below 0 °C. 5.* Pipes with a spiral seam in accordance with TU 102-39-84 with an anti-corrosion coating in accordance with TU 102-176-85 are allowed to be used only for underground inter-settlement natural gas pipelines with a pressure of up to 1.2 MPa (12 kgf/cm2) in areas with a design outside air temperature up to minus 40 °C incl. At the same time, do not use these pipes for elastic bending (rotation) of a gas pipeline in the vertical and horizontal planes with a radius of less than 1500 times the pipe diameter, as well as for laying gas pipelines in settlements. 6. Possibility of using pipes according to state standards and technical conditions given in table. 1 and 2* of this appendix, but made of semi-quiet and boiling steel, are regulated by clauses 11.7, 11.8. 7. Pipes in accordance with GOST 8731 - 87, made from ingots, should not be used without carrying out 100% non-destructive testing of the pipe metal. When ordering pipes in accordance with GOST 8731-87, indicate that pipes according to this standard, made from ingots, should not be supplied without 100% control by non-destructive methods.

Any modern metropolis and even the smallest settlement cannot do without the use of gas pipelines: both residential buildings and industrial enterprises necessarily use gas for heating and other household needs. The problem is that such engineering structures are extremely dangerous; even the slightest damage can lead to a major accident and even catastrophe. This is why there are security zones for gas pipelines.

Definition

First we need to define the very concept of “gas pipeline”. This is an engineering structure consisting of pipes and supports on which they are mounted, as well as a variety of related equipment that helps in delivering gas to the consumer.

The fuel is supplied under a certain pressure, and its transportation is highly dependent on the geographical parameters of the site. Gas pipelines are used in two types: distribution and main - depending on the pressure force. Security zones of gas pipelines also depend entirely on these parameters.

Species and types

The first type of main gas pipelines has a pressure of up to ten MPa, and the second - up to two and a half MPa. Distribution pipes come in three types: low pressure - up to five thousandths of MPa, medium pressure - up to three tenths of MPa, and high pressure - up to six tenths of MPa. Pipes are laid underground, aboveground and underwater, respectively, hence the name for this classification. The security zones of gas pipelines also differ depending on the pressure and method of installation.

The main function of protected zones is to prohibit construction in a given area. Security zones of gas pipelines are determined by special documents containing the characteristics of the pipes, the method of laying the pipeline and the permissible pressure inside.

The width of the protection zone depends on these characteristics. Thanks to it, the uninterrupted functioning of the facility, safety, integrity and possibility of maintenance are ensured. Work in the gas pipeline security zone is carried out in coordination with the organization that operates this facility.

Forbidden

In the security zone, you cannot build compost pits, build basements, work with welding, install barriers that prevent access to pipes, create landfills and willfully connect to the gas pipeline.

The security zone of a medium-pressure gas pipeline is usually equipped with special posts with signs on which the following information is given: the name and geographical location of the object, the distance to the pipeline axis, the size of the security zone, contact details of the organization that services the object. Such signs can be located on power poles and on cell phone towers.

Dimensions

Pipeline protection rules provide for the arrangement of protective territories. The security zone of the high pressure gas distribution pipeline is ten meters on either side of it. The main ones have fifty meters of protected area. If liquefied gas is delivered through pipes, the security zone is at least one hundred meters. A conventional medium-pressure pipeline requires four meters of such territory, while the protective territory of a low-pressure gas pipeline is only two meters.

Design and technical documentation necessarily contains all the information listed above and is stored in the design office, which most often is the organization for servicing this engineering structure. An act issued by local government or executive authorities and the recording of a security zone on the general plan are documents for the creation of a special territory around the gas pipeline.

Exploitation

The main activities that are carried out in the security zones by the operating organization are the following: twice a year, safety instructions are given to the owners of the land where the security zone of the main gas pipeline and any other pipeline is located; once a year - adjustment of the route with the introduction of all changes to the project documentation, and if the transformation is really necessary, the security zone of the gas pipeline itself changes. SNiP (building codes and regulations), regulating all technical, legal and economic standards, as well as engineering surveys, must be observed.

In connection with the changes discovered during the year, it is necessary to change the marking itself with special posts located at a distance of no more than five hundred meters from each other. In this way, all pipe bends are indicated, which must be repeated by the gas pipeline security zone. It doesn’t matter how many meters from one bend to another, they still need to be recorded. Also, all intersections with other infrastructure facilities (bridges, roads, etc.) must be marked with signs. A warning that a gas pipeline (main or distribution) security zone passes through this area is a mandatory condition.

Information on signs

A sign prohibiting parking and even stopping vehicles not related to the organization operating the gas pipeline is required. Along with information about the depth of the gas pipeline (if it is underground), a designation of its direction is given. The first plate stands vertically, the subsequent ones - indicating the kilometers traveled - are placed at an angle of 30 degrees for visual control from the aircraft.

It is necessary to observe all safety measures in such an important area as the gas pipeline security zone (including low pressure). This minimizes the risk and damage caused by accidents. Unauthorized work in the immediate vicinity is unacceptable, since not only a fire, but also an explosion can occur. Responsibility information is indicated on signs. The risk of damage to the gas pipeline must also be minimized.

Possible tragic accidents

Few people are insured against damage to gas pipelines and other dangerous objects. Any owner of the territory in which the security zone is located can damage the insulation or even the pipe itself if they start a large construction project or lay, for example, a water pipeline on the site without approval. Damage to pipes is a major administrative violation and provides for a fine of five thousand rubles, depending on the damage caused.

If the security zones of gas pipelines are well marked on the ground, and preventive work is carried out in a timely manner and carefully, then emergency situations associated with this type of engineering structures will not happen, which will help preserve material resources, health and even people’s lives.

Gas supply system

This is a very complex complex in which facilities are designed not just for transportation, but also for processing and distribution of gas to consumers. The system consists of the gas networks themselves, that is, three types of gas pipelines - low, high and medium pressure, as well as gas distribution stations, gas control points and installations, services and auxiliary structures. All this is intended for the normal and uninterrupted operation of the entire gas supply system. It must be safe to operate, simple and easy to maintain, and be able to shut down individual sections for repair work or in the event of an accident.

The security zone of the gas pipeline is the main condition for the safe operation of this entire system. Even the underwater passages of a gas pipeline include a special territory, regardless of the category of pipes. It will be equal to one hundred meters in each direction from the pipe.

Russian Federation rules for security zones

Gas distribution networks must have security zones of the following order:

• along the route of the external gas pipeline - two meters on each side;
• along the route of the underground gas pipeline (polyethylene pipes and copper wire marking the route) - three meters on the side of the wire and two on the other side;
• along the route of the external gas pipeline on permafrost (regardless of the material) - ten meters on each side;
• surrounding a separate gas control point - ten meters from the boundary of the facility;
• along the route of the inter-settlement gas pipeline passing through the forest or bushes - a clearing three meters wide on each side.

The low pressure gas pipeline is used for household consumers, small boiler houses, catering establishments and other similar purposes. Pipelines with medium or high pressure gas are designed for supply to city distribution networks through gas distribution points - gas distribution points. In addition, they are needed to supply gas to industrial enterprises and utilities using GRU (gas control units).

Decoding of pointers

Signposts installed in security zones are green and yellow, indicating the material from which the pipe is made: yellow - polyethylene, and green - steel. The top line on the yellow plate shows the pressure of the given gas pipeline and the pipe material. For example, PE 0.6. This means that the pipe is made of polyethylene, and the pressure in it is 0.6 MPa. If the gas pipeline is low pressure, then the letters “n.d.” will indicate this. instead of numbers.

The second line indicates the transported medium and the diameter of the pipe itself. For example, GAZ 50. This means that gas is transported through a pipe with a diameter of fifty millimeters. Variation here can only be with numbers, since the diameter of the pipes is varied.

If there is a third line, then it indicates the construction of an underground gas pipeline. For example, UP 20. This means that in this place the angle of rotation is twenty degrees.

The fourth line is the most important, it contains arrows and numbers indicating the direction from the axis of the table. For example, an arrow to the right, under which there is the number 3, and an arrow down, under which the number 7. This means that the gas pipeline is turned three meters to the right and seven meters forward.

The need to classify gas pipelines came into our lives with the widespread spread of technologies for using gas for the needs of the population. Heating of residential, administrative, and industrial buildings, the use of gas both in cooking and in production has long become a common thing for us.

The classification of gas pipelines is necessary measures and rules for systematization laying gas lines. may differ both in their purpose and in a number of indicators, such as: pressure, the material from which it is made, location, volumes of transported gas and others.

Contents of the article

About the types of classification according to the purpose of the highway

Due to the characteristic specifics of their use, gas pipes can be classified in several directions at once. After this, for an individual gas pipeline, a number of characteristics can be compiled that determine its properties and design features.

Special reference signs located along the entire gas pipeline route can tell us about this in detail. They are sign boards measuring 140x200 millimeters, with encrypted information on the gas pipeline.

Available in green (for steel options) and yellow (polyethylene pipes) colors. Signs can be placed on the walls of buildings, as well as on special posts near the routes. These signs are installed at a distance of no more than 100 meters from each other, maintaining a line of sight zone.

When planning gas pipes, one can distinguish: street, intra-block, inter-shop and yard. The characteristics of the location do not end there, because laying and inserting communications is possible on the ground, underground and above the ground.

In the gas supply system, gas pipelines can be classify according to their intended purpose:

• distribution These are external gas pipelines supplying gas from gas sources to distribution points, as well as medium and high pressure gas pipelines connected to one facility;
• gas pipeline-inlet. This is the section from the connection to the gas distribution pipeline to the inlet device that turns off the system;
• inlet gas pipeline. This is the gap from the shutdown device to the immediate internal gas pipeline;
• inter-village Such communications are laid outside populated areas;
• interior. An internal gas pipeline is considered to be the section that starts from the inlet gas pipeline to the final unit using gas.

Classification of gas pipelines by pressure

The pressure in the pipe is the most important indicator of the functioning of the gas pipeline. By calculating this indicator, it is possible to determine the capacity limit of the gas pipeline, its reliability, as well as the degree of risk that arises during its operation.

A gas pipeline, undoubtedly, is a potentially dangerous object, and therefore the laying or insertion of gas communications with a pressure exceeding the permissible carries great risks for the gas transportation system and the safety of surrounding people. Proper classification rules will help avoid accidents at explosive sites.

Separate high, medium and low pressure gas pipelines. A more detailed classification of gas pipelines is given below:

• high pressure category I-a. The gas pressure in such a gas pipeline can exceed 1.2 MPa. This type is used to connect steam and turbine units, as well as thermal power plants, to the gas system. Pipe diameter from 1000 to 1200 mm;
• high pressure category I. The indicator ranges from 0.6 to 1.2 MPa. Used to transfer gas to gas distribution points. The pipe diameter is the same as the diameter of category I-a;
• high pressure category II. Indicator from 0.3 to 0.6 MPa. Supplied to gas distribution points for residential buildings and industrial facilities. The diameter of the high pressure line is from 500 to 1000 mm;
• medium pressure category III. The indicator can be in the range from 5 kPa to 0.3 MPa. They are used to supply gas to gas distribution points through medium pressure pipes located on residential buildings. Medium pressure pipe diameter from 300 to 500 mm;
• low pressure category IV. A pressure not exceeding 5 kPa is permissible. Such gas pipes supply the carrier directly to residential buildings. Low pressure gas pipelines have a pipe diameter of no more than 300 mm.

Types of gas pipelines by depth

Taking into account the factor of urban conditions, the load from heavy transport, the influence of snow and rain on the ground, the depth of communications in the city and their main variations require consideration of them separately.

The rules for laying gas mains also depend on the type of gas being transported. Pipes supplying dried gas can be laid in the freezing zone of the soil. The depth of installation is determined primarily by the likelihood of mechanical damage to the soil or road surface.

Dynamic loads should not cause stress in the pipes. At the same time, an increase in the laying depth directly proportionally affects the cost of road repair and construction work required when laying pipes.

• on driveways of streets with concrete or asphalt pavement, the minimum laying depth is allowed to be at least 0.8 meters; in the absence of such covering, a laying depth of 0.9 meters is allowed;
• the minimum depth for laying pipes transporting dry gas is assumed to be 1.2 meters from the ground surface;
• on streets and intra-block areas where there is guaranteed to be no traffic and there will be no traffic, the laying rules allow for the laying depth to be reduced to 0.6 meters;
• The depth of the underground gas pipeline depends on the presence of water vapor and the level of soil freezing. When transporting dry gas, the laying depth is usually 0.8 meters.

Laying a gas pipeline in a trench.mp4 (video)

Main gas pipelines and their security zones

Main gas pipelines are entire complexes of technical structures, the main task of which is to transport gas from the place of its production to distribution points, and then to the consumer. In close proximity to the city they become local. The latter, in turn, serve to distribute gas throughout the city and deliver it to industrial enterprises.

The design and installation of main communications must take into account the volume of gas, the power of equipment working with it, gas pressure and, of course, the rules for laying main gas pipelines. The location of the main gas pipeline near the facility that needs to be gasified does not mean that the tie-in will be applied specifically to it.

The tie-in can be laid several kilometers from the gasified section. In addition, the tie-in must take into account the practical possibility of providing the consumer with a given power and pressure in the pipe.

Main pipes have different capacities. It is influenced, first of all, by the fuel and energy balance of the area in which the pipeline is planned to be laid. At the same time, it is necessary to rationally determine the annual amount of gas, taking into account the volume of the resource, for the future after the start of operation of the complex.

Typically, the performance parameter characterizes the amount of gas supplied per year. Throughout the year, this figure will fluctuate downward due to the uneven use of gas by the population over the seasons. In addition, this is also affected by changes in ambient temperature.

The security zone of the main gas pipeline implies a section on both sides of the gas pipeline, limited by two parallel lines. Security zones for main gas pipes are required due to the explosiveness of such communications. And therefore it must be carried out taking into account the required distance.

To maintain the required length of security zones, the following rules must be taken into account:

• for high pressure lines. Category I – the security zone is 10 m;
• for high pressure pipes Category II – the security zone is 7 m;
• for medium pressure lines. – the security zone is 4 m;
• for low pressure pipes – the security zone is 2 m.