Ways of laying external gas pipelines. How are underwater pipelines laid?

For laying an underground gas pipeline, it is necessary to provide that the roadway is blocked, and the company that installs the gas pipeline underground, using road projects, draws a terrain plan for the location of the equipment and indicates in the drawing the exact geometry of the objects that are adjacent to the buildings. This will ensure that road signs are properly positioned to restrict access to the highway or land where the underground gas system is planned to be laid.

Such an arrangement of prohibition signs must be agreed with the territorial authority of the road inspectorate, which, in turn, if a positive decision is made, must issue an authorization order for the installation of highways underground.

laying a gas pipe in a section above the ground

So, when performing installation work, the following is taken into account :

1. It is necessary to lay the gas system at a depth level, the indicator of which is at least 80 cm to the top of the structure (box). In areas where the passage of agricultural combines and equipment is not provided, a depth of at least 60 cm is allowed for the implementation of underground structures.

2. For terrain that is unstable to erosion and landslides, the depth level where the installation of the gas pipeline will take place must be at least the boundaries of the area where destructive processes are possible, and not less than 50 cm below the level of the sliding mirror.

3. In areas where highways and communication systems intersect underground for various purposes, highways that transmit a heat source, channelless systems, as well as in areas where the gas pipeline passes through the walls of wells, the structure must be placed in a box or case. If it intersects with heating networks, then installation in (steel) is needed.

4. If there are structures with different pressure indicators in a populated area, the duct should be installed at the level of engineering networks, which are located underground and which, in turn, are below the level of the gas pipeline. The ends of the box should be led out on both sides of the outer walls of the communication systems, taking into account the gap, which should not be less than 2 meters. If there is an intersection with a well, a gap of 2 cm must be observed. Using waterproofing, it must be placed on the ends of the box.

5. At the top point of the slope (except for the area where the walls of the well cross) on one side of the box, it is necessary to build a control tube, which will be located under the protective device.

6. It is not forbidden to lay an operating cable (eg, electrical protective wire, communication cable) in places between the structures of the system and the duct, which is intended for servicing distribution networks.

Distinctive features of the product

In construction work, building elements and pipes made of polyethylene are used, which have a reserve index of such a property as strength, not less than 2. Such elements are installed, their pressure index is up to 0.3 MPa, in populated areas (cities, villages) and its circumference.

It is necessary to lay products using polyethylene connecting nodes and gas ones with a margin of at least 2.6. When laying systems, the pressure drop of which is in the range of 0.306 MPa, in a populated area, it is necessary to use connecting nodes and pipes that have a strength index in reserve of at least 3.2.

laying a gas pipe underground a private house

How to carry out in the countryside?

In rural areas, it is allowed to lay a polyethylene gas pipeline together with products and connecting units made of polyethylene, the strength index of which is at least 3.2 or from Pe-100, the index of which is more than 2.6, and the depth level is at a mark of at least 90 cm to the top of the pipe.

When installing such rural structures, the pressure index of which is up to 0.6 MPa, it is allowed to use products and connectors 100 and 80. When using a system whose pressure is more than 0.3 MPa under the conditions of using PE-80, it is possible if the depth level of the device, which at least 90 cm is laid to the top of the system.

laying a gas pipe underground in the country

In the case of using inter-settlement highways, the pressure of which is higher than 1.2 MPa, it is desirable to use PE-100 connectors. In this situation, the depth level of the device used is at least one meter, and in the situation with a gas system on the ground, which is intended for irrigation and plowing, the depth level should be at least 1.2 meters to the top.

When creating gas pipelines with a pressure greater than 0.6 MPa, connectors and reinforced polyethylene products can be used. In such a situation, the depth level of at least one meter to the top of the structure, and when used on irrigation or plowing lands, the depth level of the bookmark to the top of the structure should be more than 1.2 meters.

laying a gas pipe underground technology

Laying a highway from pe-100 at a working level higher than 0.61.2 MPa in the area in the area where it enters the industrial zone, as well as in the area that is not built up, but only if this does not contradict the drawings for the placement of buildings, structures and other items of capital construction work provided for by the general plan of the settlement.

It is allowed to build a system from polyethylene using one-piece connectors, if their working condition and suitability for use in construction work are confirmed in the manner prescribed by all standards. It is forbidden to lay polyethylene structures for transporting gases that contain chlorinated and aromatic carbohydrates. The use of pipes made of copper or reinforced products for the movement of the liquid phase of LPG is prohibited.

Having an idea of ​​​​the requirements and features of such structures, it is possible, even if you do not do such work with your own hands, to keep everything under control, including the construction work that will be performed by hired workers or an organization. Possessing information in any industry, even the most minimal, can be of great benefit, both to yourself and others.

5.1.1 External gas pipelines should be placed in relation to buildings, structures and utility networks in accordance with Annexes B and C.

Ground gas pipelines in a dike are equated to underground gas pipelines, and ground ones without a dike are equated to aboveground ones.

When laying on the ground in the dike, the material and dimensions of the dike should be taken based on the thermal engineering calculation, as well as ensuring the stability of the gas pipeline and the dike.

When laying underground gas pipelines with a pressure of up to 0.6 MPa in cramped conditions, in certain sections of the route, between buildings and under the arches of buildings, as well as gas pipelines with a pressure of more than 0.6 MPa when they approach separate auxiliary buildings (buildings without the constant presence of people) it is allowed to reduce distances by no more than 50% in cramped conditions and no more than 25% in special natural conditions (see appendices B and C). At the same time, in the areas of approach and at a distance of at least 5 m in each direction from these areas, the following should be applied:

• for steel gas pipelines:
• seamless pipes;
• electric-welded pipes with 100% control by physical methods of factory welded joints;
• electric-welded pipes that have not passed the above control, laid in a protective case;
• for polyethylene gas pipelines:
• long pipes without connections;
• pipes of measured length, connected by butt welding with a heated tool, made on a welding technique of a high degree of automation, or connected by parts to the ZN;
• pipes of measured length, welded by welding equipment of an average degree of automation, laid in a case;
• cut-to-length pipes welded by manual welding technique with 100% control of joints by physical methods, laid in a case.

Mounting joints of steel gas pipelines must undergo 100% control by physical methods.

When laying gas pipelines in cramped conditions along railways, one should be guided by Appendix B.

When laying gas pipelines at a distance of less than 50 m from the railways of the general network and external railway sidings of enterprises in the approach area and at a distance of 5 m in each direction, the laying depth must be at least 2.0 m. Butt welded joints must pass 100% physical control.

At the same time, polyethylene pipes must be made of PE 100 with a safety factor of at least 3.2 and 2.0 for gas pipelines laid on the territory of settlements and urban districts, and between settlements, respectively, and the wall thickness of steel pipes should be 2- 3 mm more than calculated. For gas pipelines with pressure up to 0.3 MPa inclusive, it is allowed to use polyethylene pipes made of PE 80 with a safety factor of at least 3.2.

It is allowed to lay gas pipelines with a pressure of more than 0.6 MPa in the settlement at the entrance to the industrial center (industrial zone), as well as in the undeveloped part of the settlement, if this does not contradict the schemes for locating capital construction objects provided for by the general plan of the settlement.

5.1.2 Gas pipelines should be laid underground.

In exceptional cases, above-ground laying of gas pipelines along the walls of buildings inside residential courtyards and quarters, as well as in certain sections of the route, including sections of crossings through artificial and natural barriers, when crossing engineering and technical support networks, is allowed. Such laying of gas pipelines may be envisaged with appropriate justification and carried out in places where access of unauthorized persons to the gas pipeline is restricted.

Ground gas pipelines with dikes can be laid under special soil and hydrological conditions. The material and dimensions of the embankment should be taken on the basis of thermal engineering calculations, as well as ensuring the stability of the gas pipeline and embankment.

The height of laying of aboveground gas pipelines and the depth of laying of underground LPG gas pipelines should be taken as for gas pipelines of gas distribution networks and gas consumption of natural gas, except for specified cases.

It is allowed to lay low-pressure LPG vapor phase gas pipelines along the walls of buildings in accordance with 5.3.1 and Table 3.

The laying of gas pipelines, including LPG gas pipelines, if it is provided for by the functional requirements for the HPS and HPP, should be provided above ground.

5.1.3 Laying of gas pipelines in tunnels, collectors and channels is not allowed. The exception is the laying of steel gas pipelines with a pressure of up to 0.6 MPa in accordance with the requirements of SP 18.13330 on the territory of industrial enterprises, as well as in channels in permafrost soils under roads and railways and LPG gas pipelines under roads on the territory of gas filling stations.

5.1.4 Pipe connections should be provided as one-piece connections. Detachable can be connections of steel pipes with polyethylene and in places where technical devices and gas-using equipment are installed. Detachable connections of polyethylene pipes with steel pipes in the ground should be provided, provided that a case with a control tube is installed.

5.1.5 Gas pipelines at the points of entry and exit from the ground, as well as gas pipeline entries into buildings, must be enclosed in a case. The ends of the case at the points of entry and exit of the gas pipeline from the ground, the gap between the gas pipeline and the case at the inlets of the gas pipeline into buildings should be sealed with elastic material for the entire length of the case. The space between the wall and the case should be sealed with, for example, cement mortar, concrete, etc. for the entire thickness of the intersected structure (if possible).

Cases at the outlet and inlet of the gas pipeline from the ground, provided that it has a protective coating that is resistant to external influences, may not be installed.

5.1.6 Gas pipelines should be provided for entering buildings directly into the room in which gas-using equipment is installed, or into an adjacent room, connected by an open opening.

It is not allowed to lay gas pipelines through the foundations of buildings (except for specified cases) and under the foundations.

It is not allowed to enter gas pipelines into the premises of the basement and basement floors of buildings, except for the inputs of natural gas pipelines and low-pressure LPG vapor phase into single-family and block houses.

In seismic areas, the introduction of a gas pipeline into a non-seismic building is allowed only underground:

5.1.7 Disconnecting devices on gas pipelines should be provided for:

• in front of detached or blocked buildings;
• to disconnect the risers of residential buildings above five floors;
• in front of outdoor gas-using equipment;
• in front of the gas reduction points (GRP), with the exception of the GRP of enterprises, on the branch of the gas pipeline to which there is a disconnecting device at a distance of less than 100 m from the GRP; at the outlet of the GRP, looped by gas pipelines;
• on branches from gas pipelines to settlements, individual microdistricts, quarters, groups of residential buildings (with more than 400 apartments in a separate house), as well as on branches to industrial consumers and boiler houses;
• when crossing water barriers with two or more lines of a gas pipeline, as well as one line with a width of a water barrier with a low-water horizon of 75 m or more;
• when crossing railways of the general network and motor roads of categories I-II, if the disconnecting device that ensures the interruption of the gas supply at the crossing section is located at a distance of more than 1000 m from the roads.

At the input of gas pipelines to the pump-compressor and filling compartments, a disconnecting device with an electric drive is provided outside the building at a distance of at least 5 and not more than 30 m from the building.

5.1.8 Disconnecting devices on aboveground gas pipelines laid along the walls of buildings and on supports should be placed at a distance (within a radius) from door and opening window openings, at least, m:

• for low pressure gas pipelines of category IV - 0.5;
• for medium pressure gas pipelines of category III - 1;
• for high pressure gas pipelines of category II - 3;
• for high-pressure gas pipelines of category I - 5.

The places of installation of disconnecting devices must be protected from unauthorized access to them by unauthorized persons.

In the areas of transit laying of gas pipelines along the walls of buildings, the installation of disconnecting devices is not allowed.

Installation of disconnecting devices under balconies and loggias is also not allowed.

5.1.9 At the sites of connection to the gas distribution pipeline of gas pipelines-inlets to individual buildings for various purposes, apartment buildings, boiler houses and industrial consumers, gas flow safety valves (controllers) without a bypass hole (bypass hole for automatic pressure equalization) must be installed. Gas flow controllers are installed on a gas pipeline - an inlet with a diameter of up to 160 mm inclusive with a pressure of 0.0025 MPa at the point of its connection to the distribution gas pipeline. In other cases, the question of the need and possibility of installing a gas flow controller is decided by the design organization. It is allowed to install a gas flow controller for a single-family house in agreement with the owner.

5.2 Underground gas pipelines

5.2.1 Laying of gas pipelines should be carried out at a depth of at least 0.8 m to the top of the gas pipeline or case. In those places where the movement of vehicles and agricultural vehicles is not provided, the depth of laying steel gas pipelines is allowed at least 0.6 m.

In landslide and erosion-prone areas, gas pipelines should be laid to a depth of at least 0.5 m below the sliding mirror and below the boundary of the predicted destruction area.

5.2.2 The vertical distance (in the light) between the gas pipeline (case) and underground utility networks and structures at their intersections should be taken in accordance with Appendix B.

5.2.3 At the intersection of gas pipelines with underground communication collectors and channels for various purposes, heating mains of channelless laying, as well as at places where gas pipelines pass through the walls of gas wells, the gas pipeline should be laid in a case. When crossing with heating networks, it is necessary to provide for the laying of gas pipelines in steel cases.

Cases for polyethylene gas pipelines of all pressures on the territory of settlements should be additionally installed at the intersection with underground utility networks located below the gas pipeline route.

The ends of the case must be led out at a distance of at least 2 m on both sides from the outer walls of the structures and communications being crossed, when crossing the walls of gas wells - at a distance of at least 2 cm. The ends of the case must be sealed with waterproofing material.

At one end of the case at the top of the slope (with the exception of the intersections of the walls of the wells), a control tube should be provided that goes under the protective device.

In the annular space of the case and the gas pipeline, it is allowed to lay an operational cable (communications, telemechanics and electrical protection) with a voltage of up to 60 V, intended for servicing gas distribution networks.

5.2.4 For the construction of gas pipelines, polyethylene pipes are used in accordance with GOST R 50838 and fittings in accordance with GOST R 52779 with a safety factor of at least 2.0.

The laying of polyethylene gas pipelines with a pressure of up to 0.3 MPa inclusive in the territories of settlements (rural and urban) and urban districts should be carried out using pipes and fittings made of polyethylene PE 80 and PE 100 with a safety factor of at least 2.6.

When laying polyethylene gas pipelines with a pressure of more than 0.3 to 0.6 MPa inclusive in the territories of settlements and urban districts, pipes and fittings made of polyethylene PE 100 with a safety factor of at least 3.2 should be used. On the territory of rural settlements, it is allowed to lay polyethylene gas pipelines using pipes and fittings made of polyethylene PE 80 with a safety factor of at least 3.2 or polyethylene PE 100 with a safety factor of at least 2.6 with a laying depth of at least 0.9 m to the top of the pipe.

The safety factor of polyethylene pipes and fittings made of polyethylene PE 80 used for the construction of gas pipelines outside settlements and urban districts (inter-settlement) must be at least 2.5.

When laying inter-settlement polyethylene gas pipelines with a pressure of up to 0.6 MPa inclusive, it is allowed to use pipes and fittings made of PE 80 and PE 100 polyethylene. less than 0.9 m to the top of the pipe.

When laying inter-settlement polyethylene gas pipelines with a pressure of more than 0.6 to 1.2 MPa, inclusive, pipes and fittings made of polyethylene PE 100 must be used. the depth of the laying must be at least 1.2 m to the top of the pipe. The laying of polyethylene gas pipelines with a pressure of more than 0.6 MPa using pipes made of PE 80 is allowed provided that the laying depth is increased by at least 0.1 m.

For the construction of gas pipelines with a pressure of more than 0.6 MPa, reinforced polyethylene pipes and fittings can be used. In this case, the laying depth must be at least 1.0 m to the top of the pipe, and when laying gas pipelines on arable and irrigated lands, the laying depth must be at least 1.2 m to the top of the pipe.

It is allowed to lay polyethylene gas pipelines from PE 100 with a pressure of over 0.6 to 1.2 MPa inclusive in the settlement at the entrance to the industrial center (industrial zone), as well as in the undeveloped part of the settlement, if this does not contradict the schemes for locating capital construction objects provided for by the general plan of the settlement.

For the construction of polyethylene gas pipelines, it is allowed to use connecting parts - one-piece connections (polyethylene - steel), subject to confirmation of their suitability for use in construction in the prescribed manner.

It is not allowed to lay gas pipelines from polyethylene pipes for transporting gases containing aromatic and chlorinated hydrocarbons, as well as the vapor phase of LPG of medium and high pressure and at a temperature of the wall of gas pipelines under operating conditions below minus 20 ° C.

The use of copper and reinforced polyethylene pipes for transporting the liquid phase of LPG is not allowed.

5.3 Above ground gas pipelines

5.3.1 Above-ground gas pipelines, depending on pressure, should be placed on supports made of non-combustible materials or on building structures of buildings and structures in accordance with Table 3.

Table 3

Placement of elevated gas pipelines	Gas pressure in the gas pipeline, MPa, no more
1 On stand-alone supports, columns, overpasses, whatnots, fences, etc., as well as on the walls of industrial buildings, including gas and gas pumping stations	1.2 (for natural gas); 1.6 (for LPG)
2 Boiler rooms, industrial buildings with premises of categories C, D and D, 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:
fire resistance levels I and II, constructive fire hazard class C0	1,2*
degree of fire resistance II, class of constructive fire hazard C1 and degree of fire resistance III, class of constructive fire hazard C0	0,6*
b) along the walls of buildings:
degree of fire resistance III, class of constructive fire hazard C1, degree of fire resistance IV, class of constructive fire hazard C0	0,3*
degree of fire resistance IV, constructive fire hazard classes C1 and C2	0,1
3 Residential, administrative and household buildings for non-industrial purposes, public, including administrative purposes, as well as built-in, attached and roof boiler rooms to them, warehouse buildings of category B4 - D:
on the walls of buildings of all degrees of fire resistance	0,1**
in cases of placing GRPSh on the outer walls of buildings (only up to GRPSh)	0,3
* The gas pressure in the gas pipeline laid along the structures of buildings should not exceed the values ​​\u200b\u200bspecified in table 2 for the corresponding consumers. ** It is allowed to lay gas pipelines with a pressure of up to 0.3 MPa inclusive along the walls and roofs of gasified residential, administrative and household buildings for non-industrial purposes, public buildings, including administrative buildings, to supply gas to rooftop boilers. Notes 1 The height of the gas pipeline above the roof of the building must be at least 0.5 m. 2 Laying of LPG gas pipelines (medium and high pressure) is allowed along the walls of industrial buildings of the HPS and HPP.

5.3.2 Transit laying of gas pipelines of all pressures along the walls and above the roofs of public buildings, including administrative buildings, administrative and household buildings is not allowed.

It is forbidden to lay gas pipelines of all pressures along the walls, above and below the premises of categories A and B, except for the buildings of the GNS and GNP, determined by fire safety standards.

In justified cases, transit laying of gas pipelines is allowed not higher than the average pressure with a conditional passage of up to 100 along the walls of one residential building not lower than the degree of fire resistance III, constructive fire hazard C0 and at a distance below the roof of at least 0.2 m.

In justified cases, the transit laying of gas pipelines through the territories of facilities that are not supplied with gas from this gas pipeline must be agreed with the owner (right holder) of this facility and the operating organization.

5.3.3 High-pressure natural gas pipelines should be laid along blank walls and sections of walls or at a height of at least 0.5 m above window and door openings, as well as other open openings of the upper floors of industrial buildings and administrative and amenity buildings adjacent to them. The gas pipeline must be laid below the roof of the building at a distance of at least 0.2 m.

Natural gas pipelines of low and medium pressure may also be laid along the sashes or mullions of non-opening windows and cross the window openings of industrial buildings and boiler rooms filled with glass blocks.

5.3.4 The height of the laying of aboveground gas pipelines should be taken in accordance with the requirements of SP 18.13330.

5.3.5 On pedestrian and automobile bridges built of non-combustible materials, it is allowed to lay gas pipelines with a pressure of up to 0.6 MPa from seamless or electric-welded pipes that have passed 100% control of factory welded joints by physical methods. Laying of gas pipelines on pedestrian and automobile bridges built of combustible materials is not allowed. The laying of the gas pipeline along the bridges must prevent the ingress of gas into the closed spaces of the bridges.

5.4 Crossing of water barriers and ravines by gas pipelines

5.4.1 Underwater and surface gas pipelines in places where they cross water barriers (rivers, streams, reservoirs, canals, etc.) should be placed at a horizontal distance from bridges in accordance with Table 4.

Table 4

water barriers	Bridge type	Horizontal distance between the gas pipeline and the bridge, not less than, m, when laying the gas pipeline (downstream)
		above the bridge				below the bridge
		from the surface gas pipeline with a diameter, mm		from an underwater gas pipeline with a diameter, mm		from the surface gas pipeline	from the underwater gas pipeline
		300 or less	over 300	300 or less	over 300	all diameters
Shipping freezing	All types	75	125	75	125	50	50
Shipping non-freezing	Same	50	50	50	50	50	50
Non-navigable freezing	multi-span	75	125	75	125	50	50
Non-navigable non-freezing	Same	20	20	20	20	20	20
Non-navigable for gas pipelines:	Single and double span
low pressure		2	2	20	20	2	10
medium and high pressure		5	5	20	20	5	20
Note - The distances are given from the protruding structures of the bridge.

5.4.2 Gas pipelines at underwater crossings should be laid deep into the bottom of the crossed water barriers. If necessary, according to the results of calculations for the ascent, the pipeline is ballasted. The mark of the top of the gas pipeline (ballast, lining) should be at least 0.5 m, and at crossings through navigable and raftable water barriers - 1.0 m lower than the bottom profile predicted for a period of 25 years. When laying a gas pipeline using directional drilling, the mark must be at least 2.0 m below the predicted bottom profile.

When crossing non-navigable water barriers, it is allowed to lay underwater gas pipelines made of pipes with a ballast coating in a factory-made containment shell, without being buried in the bottom, provided that their suitability for the specified purposes is confirmed in the prescribed manner.

5.4.3 At underwater crossings, the following should be used:

• steel pipes with a wall thickness of 2 mm more than the calculated one, but not less than 5 mm; polyethylene pipes and fittings made of PE 100, having a standard dimensional ratio of not more than SDR 11 with a safety factor of at least 2.0.

When laying a gas pipeline with a pressure of up to 1.2 MPa using the directional drilling method, in all cases it is allowed to use polyethylene pipes made of PE 100 with a safety factor of at least 2.0.

At underwater crossings up to 25 m wide, located outside settlements, it is allowed to use polyethylene pipes and fittings made of PE 80 with SDR not more than SDR 11 in gas pipelines with pressure up to 0.6 MPa.

When laying a gas pipeline with a pressure of up to 0.6 MPa using the directional drilling method, in all cases it is allowed to use polyethylene pipes made of PE 80 with an SDR of not more than SDR 11.

5.4.4 The height of laying the surface crossing of the gas pipeline from the calculated level of water rise or ice drift [high water horizon (HWH) or ice drift (HWL)] to the bottom of the pipe or span should be taken:

• when crossing ravines and ravines - not less than 0.5 m above the GVV of 5% security;
• when crossing non-navigable and non-alloyable rivers - at least 0.2 m above the GWV and GVL of 2% security, and if there is a stump walker on the rivers, taking it into account, but not less than 1 m above the GWV of 1% security (taking into account surge waves);
• when crossing navigable and raftable rivers - not less than the values ​​established by the design standards for bridge crossings on navigable rivers.

Shut-off valves should be located at least 10 m from the borders of the transition or areas subject to erosion or landslides. The crossing point of the high water horizon with a 10% probability is taken as the transition boundary.

5.5 Gas pipelines crossing railways, trams and roads

5.5.1 Horizontal distances from the intersections of underground gas pipelines of tram and railway tracks, highways, main streets and roads must be at least, m:

• to bridges and tunnels on railways of general networks and external railway sidings of enterprises, tram tracks, motor roads of categories I-III, main streets and roads, as well as to pedestrian bridges, tunnels through them - 30, and for internal railway sidings of enterprises , motor roads of categories IV-V and pipes - 15;
• to the turnout zone (the beginning of the wits, the tail of the crosses, the places where suction cables are attached to the rails and other track crossings) - 4 for tram tracks and 20 for railways;
• to the supports of the contact network - 3.

It is allowed to reduce the distances indicated above in agreement with the organizations in charge of the structures being crossed.

5.5.2 Underground gas pipelines of all pressures at the intersections with railway and tram tracks, motor roads of categories I-IV, as well as with main streets and roads should be laid in cases. In other cases, the issue of the need to arrange cases is decided by the design organization.

Cases must meet the requirements for strength and durability. At one end of the case, a control tube should be provided that goes under the protective device.

5.5.3 The ends of the cases when gas pipelines cross the railways of the general network and external access railway lines of enterprises should be removed at a distance from them not less than those established by SNiP 32-01. When laying inter-settlement gas pipelines in cramped conditions and gas pipelines on the territory of settlements, it is allowed to reduce this distance to 10 m, provided that at one end of the case an exhaust candle with a sampling device is installed at a distance of at least 50 m from the bottom of the embankment, excavation of the subgrade (axis extreme rail at zero marks).

When crossing underground gas pipelines, the ends of the cases should be located at a distance of:

• at least 2 m from the bottom of the subgrade (the axis of the extreme rail at zero marks) of the tram track, internal access railway lines of enterprises;
• not less than 2 m from the curb, shoulder, slope foot of the embankment of highways, main streets and roads;
• at least 3 m from the edge of drainage structures (ditch, ditches, reserve).

In other cases, the ends of the cases should be located at a distance of:

• not less than 2 m from the outer rail of the tram track and internal access railway lines of enterprises, as well as from the edge of the carriageway of the streets;
• not less than 3 m from the edge of the drainage structure of roads (ditch, ditches, reserve), but not less than 2 m from the bottom of the embankments.5.5.4

When gas pipelines cross railways of the general network and external access railway lines of enterprises, the depth of laying the gas pipeline must comply with the requirements of SNiP 32-01.

In other cases, the depth of laying the gas pipeline from the bottom of the rail or the top of the road pavement and main streets and roads from the bottom of the embankment to the top of the case must comply with safety requirements, but be at least, m:

• 1.0 - when designing a gasket in an open way;
• 1.5 - when designing a gasket by punching or directional drilling and shield penetration;
• 2.5 - when designing the gasket by the puncture method.

When designing the laying of a gas pipeline by other methods, the depth of laying the gas pipeline is taken taking into account the requirements of technical and operational documentation and safety.

Laying of gas pipelines in the body of embankments of roads and main streets is not allowed, except for specified cases.

5.5.5 The wall thickness of the pipes of the steel gas pipeline when it crosses public railways should be 2-3 mm higher than the calculated one, but not less than 5 mm at distances of 50 m in each direction from the bottom of the slope of the embankment (the axis of the extreme rail at zero marks).

For polyethylene gas pipelines in these sections and intersections of highways of categories I-III, main streets and roads, pipes and fittings with SDR not more than SDR 11 with a safety factor of at least 3.2 should be used for gas pipelines laid in the territories of settlements and urban districts , and not less than 2.5 and 2.0 - for inter-settlement gas pipelines from PE 80 and PE 100, respectively.

At the same time, cases made of non-metallic and steel pipes should be used on gas pipelines.

5.6 Additional requirements for gas pipelines in special conditions

5.6.1 Special conditions include heaving (except for weakly heaving), subsidence (except for type I subsidence), swelling (except for slightly swelling), permafrost, rocky, eluvial soils, areas with seismicity over 6 and 7 points, undermined (except for group IV) and karst areas (except for areas where, according to the karst assessment conclusion, anti-karst measures are not required), as well as other soil and man-made conditions under which negative impacts on the gas pipeline are possible.

For cities with a population of more than 1 million people with a seismicity of more than 6 points, as well as cities with a population of more than 100 thousand people with a seismicity of more than 7 points, gas supply from two sources should be provided - main GDS or more with their placement in opposite sides of the city . At the same time, high and medium pressure gas pipelines should be designed as looped ones with their division into sections by disconnecting devices.

5.6.2 Crossings of gas pipelines across rivers up to 80 m wide, ravines and railway tracks in excavations, laid in areas with a seismicity of more than 7 points, should be provided above ground. Limiters for the movement of gas pipeline supports must ensure its free movement and exclude the possibility of dropping from the supports. In justified cases, it is allowed to lay gas pipelines from polyethylene pipes with a protective sheath.

5.6.3 When designing underground gas pipelines in seismic areas, in undermined and karst areas, at intersections with other underground utilities, at the corners of turns of gas pipelines with a bending radius of less than five diameters at the points of network branching, the transition of underground laying to aboveground, the location of permanent connections ( polyethylene - steel), as well as within the settlements on the linear sections of steel gas pipelines every 50 m, control tubes should be provided.

5.6.4 In soils of varying degrees of heaving, as well as in bulk soils with heaving properties, the depth of laying gas pipelines to the top of the pipe must be at least 0.9 of the standard freezing depth, but not less than 1.0 m. This requirement applies to areas with unequal degree of heaving and at distances equal to 50 nominal diameters of gas pipelines on both sides of their border.

With uniform heaving of soils, the depth of laying the gas pipeline to the top of the pipe should be, m:

• not less than 0.7 of the standard freezing depth, but not less than 0.9 for medium heaving soils;
• not less than 0.8 of the standard freezing depth, but not less than 1.0 for strongly and excessively heaving soils.

5.6.5 For LPG tank installations with underground tanks designed under special conditions, above-ground laying of liquid and vapor phase gas pipelines connecting the tanks should be provided.

5.6.6 In case of seismicity of more than 7 points, in undermined and karst areas, in areas of permafrost soils for polyethylene gas pipelines, the following shall be used: pipes and fittings made of PE 100 with SDR not more than SDR 11 with a safety factor of at least 3.2 for gas pipelines, laid in the territories of settlements and urban districts, and not less than 2.0 - for inter-settlement gas pipelines. It is allowed under the specified special conditions to use pipes and fittings made of PE 80 with a safety factor of at least 3.2 in polyethylene gas pipelines with a pressure of up to 0.3 MPa. When laying gas pipelines in rocky soils, pipes made of polyethylene with a protective sheath in accordance with GOST R 50838 should be used. Welded butt joints must undergo 100% control by physical methods.

5.6.7 When designing gas pipeline entries into buildings, compensation of the gas pipeline should be provided for, taking into account possible movements (settlement, bulging) of buildings and the gas pipeline itself.

5.7 Rehabilitation of worn-out underground steel gas pipelines

5.7.1 For the restoration (reconstruction) and overhaul of worn out underground steel gas pipelines, the following are used:

• in the territory of settlements and urban districts:
• at pressures up to 0.3 MPa inclusive - drawing pipes made of PE 80 and PE 100 polyethylene with a safety factor of at least 2.6 in the gas pipeline without welded joints or connected using parts with ZN, or butt-welded using high-grade welding technology automation;
• at pressures above 0.3 to 0.6 MPa inclusive - pulling pipes made of polyethylene PE 80 and PE 100 in the gas pipeline with a safety factor of at least 3.2 without welded joints or connected using parts with ZN or butt welding using welding equipment high degree of automation;
• at pressures up to 1.2 MPa inclusive - lining the cleaned inner surface of gas pipelines with a synthetic fabric hose on a special two-component adhesive, subject to confirmation in the prescribed manner of their suitability for these purposes for the specified pressure or in accordance with the standards (technical specifications), the scope of which extends to given pressure;
• outside settlements and urban districts:
• at pressures up to 0.6 MPa inclusive - drawing pipes made of polyethylene PE 80 and PE 100 in a gas pipeline with a safety factor of at least 2.6 without welded joints or connected by means of parts with ZN or butt welding using welding equipment of a high degree of automation;
• at pressures above 0.6 to 1.2 MPa inclusive - pulling pipes made of PE 100 polyethylene with a safety factor of at least 2.0 in the gas pipeline without welded joints or connected using parts with GL or butt welding using welding equipment of a high degree of automation . The space between a polyethylene pipe and a worn-out steel gas pipeline (framework) with a pressure of more than 0.6 to 1.2 MPa inclusive must be filled (if possible) along the entire length with a sealing (sealing), for example, foam material;
• at pressures up to 1.2 MPa inclusive - lining the cleaned inner surface of gas pipelines with a synthetic fabric hose on a special two-component adhesive, subject to confirmation in the prescribed manner of their suitability for these purposes for the specified pressure or in accordance with the standards (technical specifications), the scope of which extends to given pressure.

When pulling, polyethylene pipes are used without a protective sheath, with a protective sheath, with co-extrusion layers.

For the restoration (reconstruction) and overhaul of worn-out underground steel gas pipelines outside and on the territory of settlements and urban districts, other reconstruction technologies are allowed: pulling polyethylene pipes with short pipes connected to each other into a long pipe, reduced in diameter, pulling thin-walled profiled pipes SDR 21 and SDR 26, laying polyethylene pipes instead of worn-out steel pipes by their destruction or other technologies, subject to confirmation in the prescribed manner of their suitability for these purposes for the specified pressure.

5.7.2 Restoration and overhaul of worn-out steel gas pipelines may be carried out without changing the pressure, with an increase or decrease in pressure compared to the pressure in the existing gas pipeline.

It is allowed to keep:

• intersections of the restored areas with underground utilities without installing additional cases;
• depth of laying of the restored gas pipelines;
• distances from the restored gas pipeline to buildings, structures and networks of engineering and technical support according to its actual location, if the pressure in the restored gas pipeline does not change or when the pressure in the restored gas pipeline rises to 0.3 MPa.

Restoration of worn-out steel gas pipelines with the possibility of increasing pressure to high pressure is allowed if the distances to buildings, structures and utility networks meet the requirements for a high-pressure gas pipeline.

Appendix B (informative). Minimum distances from aboveground (ground without dike) gas pipelines to buildings and structures Annex B (informative). Minimum distances from underground (ground with bunding) gas pipelines to buildings and structuresAnnex D (informative). Typical solutions for restricting access to internal gas pipelines Annex D (informative). Key active measures for the safe gasification of buildingsAnnex E (informative). The procedure for registration and approval of control samples of the appearance of welded joints Annex G (informative). The act of acceptance of the completed construction of the gas distribution systemBibliography

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

Varieties of gas pipelines

Gas pipeline communications are classified depending on pressure and location.

According to the level of pressure 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 designed 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.

The low pressure gas pipeline is used to supply gas directly to dwellings, so it is necessary to build it for settlements, residential and public facilities.

By location, they can be of the following type:

• underground;
• ground;
• outdoor;
• internal.

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

Gas pipeline communications are divided into:

• gas pipelines of distribution networks.

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

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

The main components of the gas pipeline

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

Gas pipeline networks consist of:

• internal highway;
• external highway of settlements;
• automated control systems;
• means of electrochemical protection;
• regulatory items.

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 includes laying a gas pipeline underground. As a rule, such installation requires pre-prepared dug trenches. In this case, one should take into account the depth of the dug channel and the wiring of communications 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 (sewerage, heating network). It is undesirable to lay an underground gas pipeline near trees, since their root system can make it difficult to repair and operate. When laying pipes and assembling a gas device in this way, the following points should be considered:

• the gap between the gas pipeline and other underground utilities must be at least 0.2 m;
• at the intersection with communication collectors, gas pipes must be pulled in cases;
• the gas main is located above other engineering networks;
• cases should be removed from the intersection at a distance of at least 0.2 m;
• with the help of waterproofing materials, the ends of the cases are processed.

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

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

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

Laying of aboveground gas pipelines

The cost of laying a ground gas pipeline is significantly lower than the underground method. With this installation option, the pipes are laid on special supports. Above ground gas pipelines are convenient for inspection and repair, less dangerous in case of gas leakage and in terms of gas entering the premises. It should be borne in mind that the pipes must be protected as much as possible from deformation and damage as a result of corrosion, temperature extremes, and mechanical loads of various origins. The type of protection is selected depending on the climate conditions in a particular region.

When laying above ground, constant security monitoring is required, which makes it possible to prevent the possibility of unauthorized accession to the highway. From this side, the reliability of the above-ground gas pipeline is lower compared to the underground laying of pipes. For the laying of aboveground gas pipelines, there are certain rules that must be followed.

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

The distance above the ground should be:

• in places of passage of people not less than 2.2 m;
• 5 m - above highways;
• at least 7.1–7.3 m above tram and trolleybus tracks.

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

• the maximum allowable 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 wall thickness of the pipe is taken into account, it must be at least 2 mm.

Laying of external and internal gas pipelines

- a system of pipes and communications located inside buildings. The piping in this case should not be covered with any additional overlays or hidden in the wall, there should be free access for regular preventive examination and repair work.

When gas communication is located by the external method, the access of strangers to it should be as limited as possible. For this, structural elements are mounted at a sufficiently high height. The fixing of pipes to the walls of the facade must be reliable in order to prevent the fall of the gas pipe.

Advantages of using polyethylene pipes

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

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

• Not subject to aggressive environment, temperature changes, corrosion.
• Provide ease of installation (if necessary, pipe fitting, cutting).
• It is not required 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 current “wandering” in the ground, 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 cost, 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.

Restrictions on the use of polymer pipes

Despite the great demand and advantages of polymer pipes, there are limitations to 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 the earthquake can exceed seven points.
• In the case of installation of above-ground gas pipelines.
• When passing a gas structure over road or railway tracks.
• When laying gas pipeline communications that transport gas of the external and internal type.

In cases where it is impossible to install polymer pipes, steel pipes are used. If all requirements for operation are observed, 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

The laying of gas pipeline communications is a difficult and time-consuming process, which 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; on its basis, installation will be carried out in the future. The project must necessarily take into account the features of the landscape and soil of the site where the installation work will be carried out, as well as the climatic conditions of the area.

The second stage includes the direct work on the installation of gas pipelines. Next, start-up work is carried out.

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

The gas pipeline is an explosive structure, therefore no construction can be carried out in the immediate vicinity. For this, special columns are used that mark the security zone. The size of the buffer zone depends on the type of gas pipeline. Appropriate warning signs are installed where required.

Main conclusions:

• The gas pipeline is a structure that creates a danger.
• Installation requires strict adherence to safety regulations, the violation of which can lead to dangerous consequences.
• Prepare the necessary technical documentation for the permit 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, rather high speed, high degree of environmental friendliness of products. Gas is a popular type of fuel, which leads to the expansion of the scope of gas pipeline construction.

It should be borne in mind that gas as a combustible 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 an explosion.

Gasification of a private house is far from being such a simple job as it might seem at first glance. And in addition to the technical issues themselves, it will also require administrative efforts from you.

In order to at least approximately understand the procedure, having decided to carry gas into the house, we will give a few steps that must be completed in this matter:

The documents

Gas is a dangerous thing, and therefore requires an approach from several sides. Including the collection of documentation. This includes title papers for the land and the house itself, a conclusion on the technical feasibility of work, permission to carry out gasification, copies of personal documents, technical passports from the BTI, a topographic map of the location of all buildings on the site that should be gasified on a certain scale, a map of communications with the proposed gas pipeline, certified by the gas service. And this is just an approximate list. In fact, at the entire stage of the gas pipeline laying, there will be more documents. Especially when it comes to an underground gas pipeline. If the gas pipeline passes through other sections, a written permission from the owners of other sections is added.

It is also worth noting that some services will be paid, and this point must be taken into account. For example, obtaining technical conditions for conducting gas to a private house. This document is made within a month, and in order to receive it, it is necessary to provide almost all of the above papers to Gorgaz.

Project

It is impossible to carry out gas without having a clear project, which indicates not only the place, but also the details of the work itself. This document is produced exclusively by the design organization, you should not even take on an independent project, because it still has to be approved. Moreover, the design organization must be licensed, and the customer has every right to demand this license. The cost of work will depend not only on the complexity of the project and materials, but also on the organization itself. Prices are different, so it would be advisable to first take the price list, and then choose the best option. In addition, the designer will register for the installation of gas appliances.

Choosing a contractor

This issue should be approached no less responsibly. The construction and installation organization that carries out these types of work must have such a specification and all the necessary permits, as well as the qualifications of the personnel. As a rule, work on laying an above-ground or underground gas pipeline to a private house is started after all technical issues and documentary issues have been settled. At the same time, the company is obliged to provide a report on the work performed, and at the end of them close all the acts, which will accurately indicate all the actions carried out on the site.

Connection

Connection of the laid gas pipeline to the main gas pipeline. This type of work is performed by a special organization. After that, having checked everything, the gas service will connect the gas and make a number of commissioning manipulations. And the customer is obliged to listen to a lecture on safety measures for the use of a natural resource.

Underground gas pipeline

Here you should definitely warn that the underground laying of a gas pipeline will cost significantly more than the ground one. This applies not only to materials, but also to the performance of work, as well as the issuance of permits. Even despite the high cost of underground installation, it is in great demand, largely due to greater safety. The fact is that underground pipes are better preserved from environmental influences and mechanical damage. In addition, underground gas is less dangerous, and the service life of pipes will be longer.

Also, in laying an underground gas overpass from the main one, there is a nuance associated with the movement of vehicles. In the event that traffic is required to be stopped for work, these will be additional costs associated with obtaining permission from the State traffic inspectorate. Because the installation organization will be able to start work only after receiving an order to carry out work in the traffic area.

Also, the laying of a gas pipeline underground to a private house should be carried out after soil analysis. This is done in order to be sure of the reliability of the internal wire. If the soil analysis is going to be highly corrosive, then only outdoor piping is an option.

As for the material, it is better to use low-pressure polyethylene pipes for an underground overpass. They have a high density, do not react with soil or gas, do not corrode, do not crack at low temperatures and normally withstand their difference.

Worth remembering

Having decided to conduct gas to a private house, it should be taken into account that the process is quite laborious, and most importantly, this is not a matter of one month. And for this, exactly as for financial costs, one must be prepared.

The need for gas supply arises when it is necessary to provide residential buildings or industrial enterprises with thermal energy. Laying gas pipes underground is a rather complicated process, but it has a number of advantages compared to ground gas wiring. The main advantage of this type of gas pipeline is reliable protection against damage and environmental influences, which is reflected in its durability.

Highlights when laying pipes

1. Ravine depth. To equip an underground gas pipeline, a ravine is dug to such a depth that at least 0.8 m remains from the top of the pipe to the soil level - under the road and 0.6 m - in other areas.

2. Cleaning the bottom of the trench. The bottom of the trench before laying the net in it must be cleaned of debris and dirt.

3. Work in good weather. Work is not recommended during rain or immediately after it, the soil must be dry.

4. Foundation Reliability. For the reliability of the base, a layer of sand can be added to the bottom.

Measures to consider when working

The depth of the laying of gas pipes must ensure their protection from damage. The main points are as follows:

- laying depth on the site should be 1.2 to 1.7 m;

- when entering the building, the depth may decrease from 0.8 to 1.2 m;

- gas pipelines are laid with a slope of at least 1.5 mm / linear. m to ensure the removal of condensate from the gas to the condensate collectors and prevents the formation of water plugs;

- when transporting wet gas, the gas pipeline is laid below the soil freezing area and the input is placed through the foundation;

- in the case of transporting dry gas, the input is arranged above the foundation, through the wall;

- when laying more than two gas pipelines in one trench, the distance between them in the light should be at least 0.4 m for pipe volumes up to 300 mm and not less than 0.5 m for volumes greater than 300 mm.

It must be remembered that gas pipes are insulated with anti-corrosion materials before laying.

Rules for laying pipes:

- underground laying of gas pipes in trenches covered with soil is allowed, subject to the conditions of these Rules;

- at the crossings through the ravines, you need to look at the serviceability of the sod, the blind area, as well as the culverts at the bottom of the ravine and prevent the collapse of the trench by precipitation or flood waters on the slopes of the ravine;

- certain identification marks should be installed along the highway;

- when laying underground gas pipelines, detachable connections of pipes of their plastic are placed in wells.

The rules for laying gas pipes must be taken into account and adhered to in order to avoid negative consequences in the future.