The high efficiency and reliability of oil and gas pipeline transport has led to a steady increase in the length of offshore underwater pipelines. More than 60,000 km of offshore underwater oil pipelines, gas pipelines and product pipelines with a diameter of more than 100 mm have been laid in various countries of the globe.

The most developed offshore oil and gas producing regions, in which a large number of underwater pipelines have been laid, are the Gulf of Mexico and the North Sea, with significantly different conditions for the construction and operation of oil and gas transportation systems. Other areas of active offshore construction include the Caribbean Sea between Venezuela and Trinidad; the Pacific Ocean along the coast of southern California and the coast of Alaska; the seas of the Pacific Ocean washing the islands of Indonesia; the entire Persian Gulf of Arabia; southern part of the Mediterranean. Recently, the shelf of Sakhalin Island has been added to these areas.

Offshore pipeline systems are the most complex technical facilities operating in difficult natural conditions. They must remain operational when exposed to storms, currents, winds, high and low tides, withstand ice loads, and be protected from icebergs. The cost of laying one kilometer of an underwater pipeline significantly depends on many factors - the technology of its laying, the depth of the sea, the distance from coastal bases, the duration of storms, the ice-free period, the type of bottom soils - and can range from 50 thousand dollars (for a warm climate) to 8 -10 million dollars (for arctic conditions).

The current stage of development and operation of offshore oil and gas fields, which are increasingly remote from land and require the use of new technologies and increased costs for their development, is characterized by the following trends:

development of smaller deposits with the connection of transport communications to existing facilities;

use of accelerated methods of construction and installation works;

the use of underwater production systems and structures;

mining from great depths in adverse environmental conditions;

mining from deep geological structures with elevated temperatures and pressures;

application of modern methods of technical diagnostics to ensure the safe operation of pipelines and equipment;

application of modern project management methods;

wide use of modern means of computer technology, modeling, electronic means of communication and navigation.

Underwater pipeline systems are effective means of transport in the development of oil and gas resources of the continental shelf of the seas and oceans.

Severe and specific conditions for the construction and operation of pipelines, due to significant depth, waves and currents, bottom reformations and storms, shipping and fishing, labor and capital intensity of construction and repair work, as well as direct contact with a highly pollution-sensitive aquatic environment, place exceptional demands on materials, pipeline design, technology of its laying, observance of pumping and maintenance regimes.

In world practice, significant experience has been accumulated in the construction and operation of pipeline systems in offshore zones. In particular, when developing the Russian continental shelf, the experience of developing fields and creating infrastructure for transporting oil and gas in the North Sea is useful.

Underwater pipelines for the transportation of oil, oil products, associated petroleum and natural gases were used even at the initial stages of the development of the oil and gas industry.

Thus, in the construction of pipelines at the intersection of rivers, canals, straits, lakes and other bodies of water, underwater pipeline lines are predominantly laid before and now.

Significant use, especially in recent times, due to the increase in the carrying capacity of tankers, has been received by underwater pipelines connecting offshore berths with tank farms of transshipment oil depots or oil depots of coastal oil refineries. These pipelines transport oil or oil products from tankers to land and back.

In addition, many oil-producing countries every year increasingly use underwater pipelines to service offshore oil fields.

It should be noted that while the cost of laying underwater pipelines, as a rule, is much higher than on land. Reducing the cost of construction is one of the main challenges facing the offshore pipeline transport.

Drilling and offshore oil production are now carried out not only from overpasses and artificial islands, but also from special floating installations equipped with appropriate devices, equipment and fixtures for laying underwater pipelines. In the development of offshore oil fields, underwater flooded oil storage facilities are increasingly being used.

Flow lines are laid directly from the well to supply oil to group collection points, and underwater collection pipelines are laid from them, through which oil is pumped to the central collection point of the offshore oil field. From here there are underwater main pipelines, through which oil is transported to an oil depot located on the shore, on an artificial island or overpass.

With the removal of offshore fields deep into the sea and the development of oil fields on the surface, operating costs, including oil transportation, increase. The cost of foundations (platforms or vessels) for drilling and other installations is increasing significantly, the cost of laying collection pipelines on the bottom of the seas or oceans in the area of ​​​​the oil field and main pipelines for delivering oil to land is increasing.

It is calculated that with the length of sea routes of the order of several hundred kilometers, the construction of pipelines for the main transport of gas is more preferable than its transportation by tankers, which is associated with high costs for the construction and operation of natural gas liquefaction facilities.

During the construction of transcontinental offshore pipelines, the economic effect is achieved due to the absence of the need for payments for gas transit through the territory of third countries. In addition, the length of offshore pipeline routes is usually shorter than when crossing water barriers along the shore. This effect is especially pronounced when passing through relatively narrow and at the same time extended water areas, such as, for example, the Baidaratskaya Bay of the Kara Sea.

As examples of the construction of transcontinental gas pipelines, one can cite the passage through the Strait of Gibraltar and the Trans-Mediterranean pipeline from Tunisia to Italy along the bottom of the Mediterranean Sea.

Currently, the most famous project is the Blue Stream, which involves the construction of an offshore section of a gas pipeline under the Black Sea from Russia directly to Turkey. Its peculiarity lies primarily in the significant depth of the sea (2150 m) and complex geological conditions.

The development of oil and gas fields located on the shelf is impossible without the construction of pipelines. In modern offshore oilfields, some subsea pipelines connect individual offshore platforms with a central reservoir and a floating berth, which is equipped for mooring tankers, while others connect the reservoirs directly with an onshore oil storage facility.

The offshore pipeline construction technology includes the following stages: excavation, preparation of the pipeline for laying, its laying, backfilling and protection from damage.

The need to bury offshore pipelines is due to the fact that otherwise they can be damaged when moving coastal ice, trawls, ship anchors, etc. During earthworks, devices are used that develop a trench, both from the surface of the water and in a submerged position. The former include floating dredgers, jet installations, clamshell dredges, pneumatic and hydraulic soil pumps. To the second - various kinds of autonomous devices operating under water.

So, in Italy, the S-23 dredge was created, which can develop trenches at a depth of up to 60 m. Digging of a trench is carried out by a milling ripper at a speed of up to 130 m/h in soils of medium density. The parameters of the trench to be torn off are as follows: depth - up to 2.5 m, width along the bottom - from 1.8 to 4.5 m.

In Japan, a bulldozer and an excavator have been developed for working under water at a depth of up to 70 m. The bulldozer weighing 34 tons has a powerful engine and moves on tracks. Unlike dredgers, it can develop dense soils.

The underwater excavator is designed for excavation of trenches during the construction of offshore pipelines, foundation pits for the foundations of various offshore structures and dredging. The speed of its movement along the bottom is 3 km / h. The excavator is operated by two operators from a surface vessel.

Before laying, a protective coating is applied to the pipeline and it is surcharged against ascent. World experience in the construction of offshore pipelines has shown that the best protective coating for them and at the same time a weight is a concrete coating.

Laying of offshore pipelines is carried out by pulling, or from the sea surface by gradual build-up.

The pulling scheme is shown in fig. 4. The pipeline 1 moves along the roller descent path 5. The traction force along the cable 2 is transmitted from the winch installed on the vessel 3. The vessel is held by anchors 4. The pulling method is simple, ensures the laying of the pipeline exactly along the route. However, it is applicable when laying pipelines up to 15 km long.

The scheme of laying from the sea surface with a gradual build-up (Fig. 5) is the most widely used. The pipe-laying vessel 4 is fixed on anchors 6, each of which can withstand a force of up to 10 tons. A stock of concreted pipes is created on the vessel, sections of which are 36 m long and delivered by special transport vessels. The length of the pipe-laying vessel makes it possible to connect sections in a 180 m long string.

Pipeline 1 is laid as follows. On the ship 4, the next lash is welded, the joints are insulated, concreted and equipped with floats 2. The lash is joined to the end of the pipeline laid earlier and held by the tension device and a special rigid attachment 3. The angle of inclination of this attachment is chosen so as to minimize the stress in the lowered pipeline. The joint is isolated and concreted, after which the whips are lowered into the water on pontoons. Unslinging of pontoons is carried out automatically at a predetermined depth.

The ship "Suleiman Vezirov" with a displacement of 8900 tons per day can lay 1.2 km of welded pipes with a diameter of 200 ... 800 mm under water. The pipe-laying vessel of the Vartsila company with a displacement of 41,000 tons allows laying up to 2.5 km of a pipeline with a diameter of 530 mm per day at a depth of up to 300 m. The supply of pipes is enough for them to work for 5 ... 10 days.

Laying offshore pipelines with a preliminary excavation of the trench is associated with significant costs. Trenching at sea costs a hundred times more than on land. In addition, it is quite difficult to accurately lay the pipe in a trench from the side of a ship rocking on the waves.

It is cheaper and easier to bury a steel pipeline already laid on the bottom into the ground. For this, special underwater pipe deepening units have been designed. Their main element is a trolley that rolls along the pipe.

Fig 4 - Scheme of pulling through the pipeline: 1 - pipeline; 2 - cable; 3 - the vessel on which the winch is installed; 4 - anchors.

Figure 5 - Scheme of laying the pipeline by a pipe-laying vessel: 1 - pipeline; 2 - floats; 3 - rigid prefix on which the end of the pipeline lies; 4 - pipe-laying vessel; 5 - crane; 6 anchors.

Various deepening devices are fixed on the trolley: jet nozzles, plows, cutters or rotary wheels. The energy for their drive is supplied from the ship via a cable line, which reaches a length of 1 km or more. Recently, pipe deepeners are equipped with underwater cameras, which makes it possible to control their operation from the surface.

Rock placement is most commonly used to protect offshore pipelines from damage in the coastal zone. The stone is dumped from the side of barges with inclined bunkers and vibrators. Vessels with a smooth deck are often used, overboard of which stones are dumped by a bulldozer. The accuracy of such filling is low. Therefore, at present, the role of a bulldozer is performed by special shields controlled by hydraulic cylinders connected to a computer. Such devices allow high-quality backfilling of the pipeline with waves as high as a two-story house and wind speeds up to 15 m / s.

Another way to protect offshore pipelines from damage is to lay asphalt over the trench. Asphalting of the seabed is carried out using a floating asphalt plant. From its deck, the finished mixture is fed to the bottom through a vertical pipe, in the center of which a heater pipe passes so that the asphalt does not have time to cool due to contact with relatively cold water. At the bottom, the asphalt is leveled and compacted by an automatic device similar to those used for asphalting squares and streets. In one pass of the stacker, an asphalted area with a width of 5 m and a thickness of 85 mm appears on the bottom.

These departmental building codes (VSN) are intended for the design and construction of offshore gas pipelines.

The VSN contains the basic requirements for the design and construction of offshore gas pipelines on the Russian continental shelf with a diameter of up to 720 mm and an internal working pressure of not more than 25 MPa. When specifying the construction region, these VSNs must be supplemented with requirements that take into account the specifics of this region.

The designations and units of measurement used in these rules and regulations are given in.

The technical terms and definitions adopted in these rules and regulations are given in

The list of regulatory documents used in the development of these rules and regulations is given in

Developed and introduced JSC VNIIST DOAO Giprospetsgaz VNIIGAZ

Approved by Gazprom

PART 1. DESIGN STANDARDS

1. General Provisions

1.1. Offshore main gas pipelines must have increased reliability during construction and operation, taking into account special conditions (great sea depths, increased length without intermediate compressor stations, sea storms, undercurrents, seismicity and other factors).

Design decisions for laying offshore gas pipelines must be coordinated with the State Committee of the Russian Federation for Environmental Protection, Gosgortekhnadzor of Russia and local supervisory authorities.

1.2. Protective zones are established along the route of the offshore gas pipeline, which include sections of the main gas pipeline from compressor stations to the water's edge and further along the seabed within the continental shelf, at a distance of at least 500 m.

1.3. The diameter of the offshore gas pipeline and the value of the working pressure are determined from the conditions for the supply of natural gas to the Consumer on the basis of hydraulic analysis.

1.4. The service life of the offshore gas pipeline is set by the Project Owner. For the entire service life of the gas pipeline system, the reliability and safety of the structure and such influences as metal corrosion and fatigue of the materials used must be calculated.

1.5. The boundaries of the offshore section of the main gas pipeline are shut-off valves installed on opposite shores of the sea. Shut-off valves must be equipped with automatic emergency closing.

1.6. At the ends of each string of the offshore gas pipeline, units for launching and receiving cleaning devices and flaw detector projectiles should be provided. The location and design of these nodes are determined by the project.

1.7. The offshore gas pipeline must be free from obstructions to the flow of the transported product. In the case of using artificial bending curves or fittings, their radius must be sufficient for the passage of cleaning and control devices, but not less than 10 pipeline diameters.

1.8. The distance between parallel lines of offshore gas pipelines should be taken from the conditions of ensuring reliability during their operation, the safety of the existing line during the construction of a new line of the gas pipeline and safety during construction and installation work.

1.9. Offshore pipeline protection against corrosion is carried out in a complex way: by a protective outer and inner coating and cathodic protection means.

Anti-corrosion protection should contribute to the trouble-free operation of the offshore pipeline throughout the entire period of its operation.

1.10. The offshore pipeline must have an insulating connection (flange or sleeve) with a corrosion protection system for onshore sections of the main gas pipeline.

1.11. The choice of the offshore pipeline route should be made according to the criteria of optimality and be based on the following data:

· soil conditions of the seabed;

seabed bathymetry;

morphology of the seabed;

initial information about the environment;

· seismic activity;

Fishing areas

ship fairways and places of mooring of vessels;

areas of soil dumping;

water areas with increased environmental risk;

The nature and extent of tectonic faults. The technical and environmental safety of the structure should be taken as the main criteria for optimality.

1.12. The project must provide data on the physical and chemical composition of the transported product, its density, as well as indicate the calculated internal pressure and design temperature along the entire pipeline route. Information is also given on the temperature and pressure limits in the pipeline.

Permissible concentrations of corrosive components in the transported gas should be indicated: sulfur compounds, water, chlorides, oxygen, carbon dioxide and hydrogen sulfide.

1.13. The development of the project is based on the analysis of the following main factors:

direction and speed of the wind;

height, period and direction of sea waves;

speed and direction of sea currents;

level of astronomical high and low tide;

· storm surge of water;

The properties of sea water

temperature of air and water;

· growth of marine fouling on the pipeline;

seismic environment;

· Distribution of commercial and protected species of marine flora and fauna.

1.14. The project should include an analysis of the allowable spans and stability of the pipeline on the seabed, as well as the calculation of branch pipes - limiters of the avalanche collapse of the pipeline during its laying at great depths of the sea.

1.15. The gas pipeline should be buried in the bottom in the areas of its landfall. The design elevation of the top of the pipeline buried in the ground (by weight coating) should be set below the predicted depth of erosion of the bottom of the water area or onshore section for the entire period of operation of the offshore pipeline.

1.16. In deep-water sections, the gas pipeline can be laid on the surface of the seabed, provided that its design position is ensured during the entire period of operation. At the same time, it is necessary to justify the exclusion of the rise or movement of the pipeline under the influence of external loads and its damage by fishing trawls or vessel anchors.

1.17. When designing an offshore pipeline system, all types of impacts on the pipeline that may require additional protection should be taken into account:

the occurrence and spread of cracking or collapse of pipes and welds during installation or operation;

· Loss of pipeline stability on the seabed;

· loss of mechanical and service properties of pipe steel during operation;

· unacceptably large spans of the pipeline at the bottom;

erosion of the seabed;

· strikes on the pipeline by anchors of vessels or fishing trawls;

earthquakes;

Violation of the technological regime of gas transportation. The choice of protection method is adopted in the project depending on local environmental conditions and the degree of potential threat to the offshore gas pipeline.

1.18. The following data should be reflected in the design documentation: pipe dimensions, type of transported product, service life of the pipeline system, water depth along the gas pipeline route, type and class of steel, the need for heat treatment after welding of girth field welded joints, anti-corrosion protection system, plans for the future development of regions along pipeline system routes, scope of work and construction schedules.

On the drawings, it is necessary to indicate the location of the pipeline system in relation to nearby settlements and harbors, the courses of ships, as well as other types of structures that can affect the reliability of the pipeline system.

The project takes into account all types of loads that occur during the manufacture, installation and operation of the pipeline system, which may affect the choice of design solution. All necessary calculations of the pipeline system for these loads are performed, including: analysis of the strength of the pipeline system during installation and operation, analysis of the stability of the position of the pipeline on the seabed, analysis of fatigue and brittle fracture of the pipeline, taking into account welded circumferential seams, analysis of the stability of the pipe wall against collapse and excessive deformations , vibration analysis, if necessary, analysis of the stability of the seabed base.

1.19. As part of the offshore gas pipeline project, it is necessary to develop the following documentation:

Specifications for pipe material;

Specifications for pipe welding and non-destructive testing, indicating the norms for permissible defects in welds;

· specifications for reinforced inserts to limit the avalanche collapse of the pipeline;

Specifications for external and internal anti-corrosion coating of pipes;

Specifications for the weight coating of pipes;

· specifications for the material for the manufacture of anodes;

· technical conditions for laying the offshore section of the pipeline;

· technical conditions for the construction of the pipeline when crossing the coastline and coastal protection measures;

· specifications for testing and commissioning of the offshore pipeline;

· technical conditions for the maintenance and repair of the offshore pipeline;

general specification of materials;

Description of construction boats and other equipment used.

When developing "Specifications" and "Specifications", the requirements of these standards and the recommendations of generally recognized international standards (1993), DNV (1996) and (1993), as well as the results of scientific research on this issue, should be used.

1.20. Design documentation, including test reports, survey materials and initial diagnostics, must be retained throughout the entire service life of the offshore pipeline system. It is also necessary to save reports on the operation of the pipeline system, on inspection control during its operation, as well as data on the maintenance of the offshore pipeline system.

1.21. Examination of design documentation should be carried out by independent organizations, to which the design organization provides all the necessary documentation.

2. Design criteria for pipelines.

2.1. The strength criteria in these codes are based on allowable stresses, taking into account residual welding stresses. Limit state design methods may also be used, provided these methods provide the reliability of the offshore pipeline system required by this code.

2.2. Calculations of the offshore gas pipeline must be made for static and dynamic loads and impacts, taking into account the operation of welded circumferential seams in accordance with the requirements of structural mechanics, strength of materials and soil mechanics, as well as the requirements of these standards.

2.3. The accuracy of calculation methods should be justified by practical and economic feasibility. The results of analytical and numerical solutions, if necessary, must be confirmed by laboratory or field tests.

2.4. The calculation of the offshore gas pipeline is made for the most unfavorable combination of actually expected loads.

2.5. For an offshore gas pipeline, calculations should be performed separately for the loads and impacts arising during its construction, including hydrostatic tests, and for the loads and impacts arising during the operation of the offshore pipeline system.

2.6. When calculating strength and deformability, the main physical characteristics of steel should be taken according to the "Specifications for Pipe Material".

3. Loads and impacts.

3.1. In these standards, the following combinations of loads are accepted in the calculations of the offshore gas pipeline:

permanent loads;

· constantly operating loadings together with loadings of environment;

· permanent loads in combination with random loads.

3.2. The permanent loads on the offshore pipeline during its construction and subsequent operation include:

· the weight of the pipeline structure, including weight coating, marine fouling, etc.;

external hydrostatic pressure of sea water;

buoyancy force of the aquatic environment;

internal pressure of the transported product;

temperature influences;

backfill soil pressure.

3.3. Environmental impacts on an offshore pipeline include:

loads caused by underwater currents;

· Loads caused by sea waves.

When calculating the offshore pipeline for the period of construction, one should also take into account the loads from construction mechanisms and the loads arising in the process of hydrostatic tests.

3.4. Random loads include: seismic activity, seabed soil deformation and landslide processes.

3.5. When determining the loads and impacts on the offshore pipeline, it should be based on the data of engineering surveys carried out in the area of ​​the pipeline route, including engineering-geological, meteorological, seismic and other types of surveys.

Loads and impacts should be selected taking into account the predicted changes in environmental conditions and the technological regime of gas transportation.

4. Permissible design stresses and strains.

4.1. Permissible stresses in the calculations for the strength and stability of offshore pipelines are established depending on the yield strength of the metal of the pipes used using the design coefficient "K", the values ​​of which are given in

s additional £ K × s T (1)

The values ​​of the design coefficients of reliability "K" for offshore gas pipelines.

Ring tensile stresses under permanent loads		Total stresses for constant loads in combination with environmental loads or random loads	Total stresses during construction or hydrostatic testing
Offshore gas pipeline	Onshore and coastal sections of the gas pipeline in the protected zone		Offshore gas pipeline, including onshore and coastal sections in the protected zone
0,72	0,60	0,80	0,96

4.2. The maximum total stresses caused by internal and external pressure, longitudinal forces, taking into account the ovality of the pipes, should not exceed the allowable values:

4.3. Pipelines should be checked for strength and local stability of the pipe section against external hydrostatic pressure. In this case, the internal pressure in the pipeline is assumed to be 0.1 MPa.

4.4. The value of the ovality of the pipes is set by the formula:

(3)

The permissible total ovality, including the initial ovality of the pipes (factory tolerances), should not exceed 1.0% (0.01).

4.5. The residual deformation in the offshore pipeline should not exceed 0.2% (0.002).

4.6. In areas of possible subsidence of the offshore pipeline, it is necessary to calculate the predicted curvature of the pipeline axis from its own weight, taking into account external loads.

4.7. The project should analyze all possible stress fluctuations in the pipeline in terms of intensity and frequency that can cause fatigue failure during construction or during further operation of the offshore pipeline system (hydrodynamic effects on the pipeline, fluctuations in operating pressure and temperature, and others). Particular attention should be paid to sections of the pipeline system prone to stress concentration.

4.8. To calculate fatigue phenomena, it is possible to use techniques based on fracture mechanics when testing pipes for low-cycle fatigue.

5. Calculation of the pipeline wall thickness.

5.1. For an offshore gas pipeline, the pipe wall thickness should be calculated for two situations determined by the acting loads:

On the internal pressure in the pipeline for shallow, onshore and coastal sections of the gas pipeline located in the protected zone;

On the collapse of the gas pipeline under the influence of external pressure, stretching and bending for deep water sections along the pipeline route.

5.2. Calculation of the minimum wall thickness of the offshore gas pipeline under the influence of internal pressure should be made according to the formula:

()

Note:

The given dependence is applicable for the range of calculated temperatures of the transported gas between -15°C and + 120°C, provided that the welded joints are equal in strength with the base metal of the pipes and the necessary hardness of the welded ring joints and their resistance to hydrogen sulfide cracking are ensured.

5.3. The nominal thickness of the pipe wall is set according to the minimum thickness obtained by the formula (), rounded up to the nearest higher value provided for by state standards or specifications.

5.4. The thickness of the pipeline wall must be sufficient, taking into account the loads arising during installation, laying, hydraulic testing of the pipeline and during its operation.

5.5. If necessary, it is possible to add allowances for internal corrosion to the calculated nominal thickness of the pipeline wall.

If a corrosion monitoring program or inhibitor injection is envisaged, the addition of corrosion allowances is not required.

5.6. To prevent collapse of the pipeline wall in the deep water sections of the route under the influence of external pressure, stretching and bending, the following condition must be met:

(5)

5.7. When determining the wall thickness of pipes under the conditions of the combined effect of bending and compression, the value of the compressive yield strength equal to 0.9 of the yield strength of the pipe material should be taken into account in the calculations.

5.8. When using laying methods with full control of the bending deformation of the pipeline, the allowable bending deformation when laying the pipeline at sea depths of more than 1000 m should not exceed 0.15% (0.0015). In this case, the critical value of the bending deformation of the pipeline at such depths will be 0.4% (0.004).

6. Stability of the pipeline wall under the influence of external hydrostatic pressure and bending moment.

6.1. For ratio range 15

(6)

(7)

In this case, the initial ovality of the pipe should not exceed 0.5% (0.005).

6.2. The external hydrostatic pressure on the pipe at the actual water depth is determined by the formula:

(9)

6.3. It should also be taken into account that at a pressure exceeding the critical value, local transverse collapse of the pipe can develop along the longitudinal axis of the pipeline.

The external hydrostatic pressure at which the propagation of the previously occurring collapse can occur is determined by the formula:

(10)

6.4. To prevent the development of collapse along the length of the pipeline, it is necessary to provide for the installation of collapse limiters in the form of stiffening rings or nozzles with an increased wall thickness on the pipeline.

The length of the limiters must be at least four pipe diameters.

7. Stability of the pipeline on the seabed under the influence of hydrodynamic loads.

7.1. Pipeline calculations should be carried out to check the stability of the pipeline position on the seabed during its construction and operation.

If the pipeline is buried in unstable soil and its density is less than the density of the surrounding soil, it should be established that the resistance of the soil to shear forces is sufficient to prevent the pipeline from floating to the surface.

7.2. The relative density of the pipeline with a weight coating should be greater than the density of sea water, taking into account the presence of suspended soil particles and dissolved salts in it.

7.3. The value of the negative buoyancy of the pipeline from the condition of stability of its position on the seabed is determined by the formula:

(11)

7.4. When determining the stability of offshore pipelines on the seabed under the influence of hydrodynamic loads, the design characteristics of wind, water level and wave elements should be taken in accordance with the requirements
*.

It is allowed to assess the hydrodynamic stability of the pipeline using analysis methods that take into account the movement of the pipeline in the process of self-burrowing into the ground.

7.5. Maximum horizontal ( R x + R i) and the corresponding vertical Pz projection of the linear load from waves and sea currents acting on the pipeline, must be determined by the formulas *.

7.6. Calculations of the velocities of bottom currents and wave loads should be made for two cases:

· repeatability once in 100 years when calculating for the period of operation of the offshore pipeline system;

· repeatability once a year in calculations for the period of construction of the offshore pipeline system.

7.7. Friction coefficient values ​​must be taken from engineering survey data for the corresponding pounds along the offshore pipeline route.

8. Materials and products.

8.1. Materials and products used in the offshore pipeline system must meet the requirements of approved standards, specifications and other regulatory documents.

It is not allowed to use materials and products for which there are no certificates, technical certificates, passports and other documents confirming their quality.

8.2. The requirements for the material of pipes and fittings, as well as for shut-off and control valves must meet the requirements of the "Specifications" for these products, which include: product manufacturing technology, chemical composition, heat treatment, mechanical properties, quality control, accompanying documentation and marking .

If necessary, the "Technical conditions" provide requirements for special tests of pipes and their welded joints, including in a hydrogen sulfide environment, in order to obtain their positive results before the start of production of the main batch of pipes intended for the construction of an offshore gas pipeline.

8.3. The "Specifications for pipe welding and non-destructive testing" should indicate the requirements for defects in welds, under which it is allowed to repair girth welded joints of the pipeline. It is also necessary to provide data on the heat treatment of welded joints or their concomitant heating after welding during pipeline installation.

8.4. For welding electrodes and other products, specifications for their manufacture must be submitted.

8.5. Tolerances for ovality of pipes during their manufacture (factory tolerance) in any section of the pipe should not exceed + 0.5%.

8.6. Connectors intended for offshore pipelines shall be factory tested with a hydraulic pressure of 1.5 times the working pressure.

8.7. The following welding consumables can be used for automatic welding of pipe joints:

ceramic or fused fluxes of special compositions;

· Welding wires of special chemical composition for submerged arc welding or shielding gases;

gaseous argon;

special mixtures of argon with carbon dioxide;

self-shielded flux-cored wire.

Combinations of specific grades of fluxes and wires, grades of self-shielded flux-cored wires and wires for shielded welding, must be selected taking into account their resistance in a hydrogen sulfide environment and be certified in accordance with the requirements of the "Technical Specifications for Pipe Welding and Non-Destructive Testing".

8.8. For manual arc welding and offshore pipeline repair, basic or cellulosic electrodes should be used. Specific brands of welding electrodes must be selected taking into account their resistance in a hydrogen sulfide environment and be certified in accordance with the requirements of the "Specifications for Pipe Welding and Non-Destructive Testing".

8.9. The pipe weight coating shall be steel mesh reinforced concrete applied to individual insulated pipes at the factory in accordance with the requirements of the "Pipe Weight Coating Specification".

The class and brand of concrete, its density, the thickness of the concrete coating, the mass of the concreted pipe are determined by the project.

Steel reinforcement should not form electrical contact with the pipe or anodes, and should not extend to the outer surface of the coating.

Sufficient adhesion must be provided between the weight coating and the pipe to prevent slippage under the forces that arise during the laying and operation of the pipeline.

8.10. Reinforced concrete coating on pipes must have chemical and mechanical resistance to environmental influences. The type of fittings is selected depending on the loads on the pipeline and operating conditions. Concrete for weight coating must have sufficient strength and durability.

Each concrete pipe entering the construction site must have a special marking.

PART 2. PRODUCTION AND ACCEPTANCE OF WORKS

1. General Provisions

During the construction of offshore gas pipelines, experience-tested technological processes, equipment and construction equipment should be used.

2. Welding of pipes and methods of control of welded joints.

2.1. Pipe connections during construction can be performed using two organizational schemes:

· with preliminary welding of pipes into two- or four-pipe sections, which are then welded into a continuous thread;

welding of individual pipes into a continuous thread.

2.2. The welding process is carried out in accordance with the "Specifications for pipe welding and non-destructive testing" in one of the following ways:

· automatic or semi-automatic welding in shielding gas with a consumable or non-consumable electrode;

· automatic or semi-automatic welding with self-shielded wire with forced or free formation of the weld metal;

· manual welding by electrodes with a covering of the basic type or with a cellulose covering;

· electrocontact welding by continuous fusion with post-weld heat treatment and radiographic quality control of welded joints.

When welding two or four pipe sections on the auxiliary line, automatic submerged arc welding can also be used.

"Specifications" are developed as part of the project by the Contractor and approved by the Customer on the basis of conducting studies on the weldability of a pilot batch of pipes and obtaining the necessary properties of welded ring joints, including their reliability and performance in a hydrogen sulfide environment, and conducting the appropriate certification of welding technology.

2.3. Before starting construction work, welding methods, welding equipment and materials accepted for use must be certified at the welding base or on the pipe-laying vessel in conditions close to construction conditions, in the presence of the Customer's representatives and accepted by the Customer.

2.4. All operators of automatic and semi-automatic welding, as well as hand-held welders, must be certified in accordance with the requirements of DNV (1996) or taking into account additional requirements for the resistance of welded joints when working in a hydrogen sulfide environment.

Certification must be carried out in the presence of representatives of the Customer.

2.5. Welders who must perform underwater welding must additionally undergo appropriate training, and then special certification in a pressure chamber with simulated natural working conditions on the seabed.

2.6. Welded ring joints of pipes must comply with the requirements of the "Specifications for Pipe Welding and Non-Destructive Testing".

2.7. Circumferential welded joints are subjected to 100% radiographic control with duplication of 20% of the joints by automated ultrasonic control with recording of the control results on tape.

Upon agreement with the Customer, it is allowed to use 100% automated ultrasonic testing with a tape recording of 25% of duplicate radiographic testing.

Acceptance of welded joints is carried out in accordance with the requirements of the "Specifications for Pipe Welding and Non-Destructive Testing", which should include the norms for permissible defects in welds.

2.8. Circumferential welds are considered accepted only after they have been approved by the Employer's representative based on review of radiographic images and records of ultrasonic testing results. Documentation with records of the results of the welding process and the control of welded pipe joints is kept by the operating organization of the pipeline throughout the entire service life of the offshore pipeline.

2.9. With appropriate justification, it is allowed to connect the pipeline strings or repair work on the seabed, using docking devices and hyperbaric welding. The underwater welding process shall be classified by appropriate tests.

3. Corrosion protection

3.1. The offshore gas pipeline must be insulated over the entire outer and inner surface with an anti-corrosion coating. Pipe insulation must be carried out in factory or basic conditions.

3.2. The insulating coating must comply with the requirements of the "Specifications for External and Internal Anti-Corrosion Coating of Pipes" for the entire service life of the pipeline in terms of the following indicators: tensile strength, relative elongation at operating temperature, impact strength, adhesion to steel, maximum peel area in sea water, fungus resistance, resistance to indentation.

3.3. The insulation must withstand breakdown tests at a voltage of at least
5 kV per millimeter of thickness.

3.4. Insulation of welded joints, valve assemblies and shaped fittings must meet the requirements for pipe insulation in terms of its characteristics.

Insulation of the connection points of electrochemical protection devices and instrumentation, as well as restored insulation in damaged areas, must ensure reliable adhesion and corrosion protection of pipe metal.

3.5. When performing insulation work, the following must be carried out:

quality control of the materials used;

· step-by-step quality control of stages of insulation works.

3.6. During transportation, handling and storage of pipes, special measures must be taken to prevent mechanical damage to the insulating coating.

3.7. The insulating coating on the pipeline sections completed by construction is subject to control by the cathodic polarization method.

3.8. Electrochemical protection of the offshore pipeline system is carried out using protectors. All electrochemical protection equipment must be designed for the full life of the offshore gas pipeline system.

3.9. The protectors must be made of materials (alloys based on aluminum or zinc) that have passed full-scale tests and meet the requirements of the "Specifications for the material for the manufacture of anodes" developed as part of the project.

3.10. Protectors need to have two connecting cables with a pipe. Bracelet-type protectors are installed on the pipeline in such a way as to avoid mechanical damage during transportation and laying of the pipeline.

The drain cables of protective devices should be connected to the pipeline using manual argon-arc or capacitor welding.

Upon agreement with the Customer, manual arc welding with electrodes can be used.

3.11. On the offshore pipeline, potentials must be provided continuously over its entire surface during the entire period of operation. For sea water, the minimum and maximum values ​​​​of protective potentials are given in. These potentials are calculated for sea water with a salinity of 32 to 28%o at a temperature of 5 to 25°C.

Minimum and maximum protective potentials

3.12. Electrochemical protection must be put into effect no later than 10 days from the date of completion of the pipeline laying.

4. Landfalls of the pipeline

4.1. The following construction methods may be used for pipeline landfall:

· open excavation works with the installation of sheet piling on the foreshore;

· directional drilling, in which the pipeline is pulled through a pre-drilled well in an offshore area;

tunnel method.

4.2. When choosing a pipeline construction method at the landfall sections, the relief of the coastal sections and other local conditions in the construction area, as well as the equipment of the construction organization with the technical means used to carry out the work, should be taken into account.

4.3. Pipeline landfalls using directional drilling or a tunnel must be substantiated in the project by the economic and environmental feasibility of their use.

4.4. During the construction of the pipeline on the coastal section with the use of underwater earthworks, the following technological schemes can be applied:

· a pipeline string of the required length is made on a pipe-laying vessel and pulled to the shore along the bottom of a previously prepared underwater trench using a traction winch installed on the shore;

· The pipeline string is manufactured onshore, hydrostatically tested and then pulled into the sea along the bottom of an underwater trench using a traction winch installed on a pipe-laying vessel.

4.5. The construction of the offshore pipeline in the coastal areas is carried out in accordance with the requirements of the "Technical Specifications for the Construction of a Pipeline at the Crossing of the Shoreline", developed as part of the project.

5. Underwater excavation

5.1. The technological processes of developing a trench, laying a pipeline in a trench and filling it with soil should be maximally combined in time, taking into account the drift of the trench and the reshaping of its transverse profile. When backfilling underwater trenches, technological measures should be developed that minimize the loss of soil outside the trench boundaries.

The technology for the development of underwater trenches must be agreed with environmental authorities.

5.2. The parameters of the underwater trench should be as minimal as possible, for which increased accuracy in their development should be ensured. The requirements of increased accuracy also apply to backfilling of the pipeline.

In the zone of transformation of sea waves, more gentle slopes should be assigned, taking into account the reformation of the cross section of the trench.

5.3. Parameters of an underwater trench in areas whose depths, taking into account
surge and tidal fluctuations in the water level, less than the draft of earth-moving equipment, should be taken in accordance with the standards for the operation of sea vessels and ensuring safe depths within the boundaries of the working movements of earth-moving equipment and ships serving it.

5.4. Temporary stockpiles should be kept to a minimum. The location of the storage of the developed soil should be chosen taking into account the minimum environmental pollution and agreed with the organizations that control the ecological state of the construction area.

5.5. If the project allows the use of local soil for backfilling the trench, then during the construction of a multi-line pipeline system, it is allowed to fill the trench with the laid pipeline with soil torn from the trench of the parallel line.

6. Laying from a pipe-laying vessel

6.1. The choice of offshore pipeline laying method is based on its technological feasibility, economic efficiency and environmental safety. For deep seas, S-curve and J-curve laying methods using a pipe-lay vessel are recommended.

6.2. The laying of the offshore pipeline is carried out in accordance with the requirements of the "Specifications for the construction of the offshore section of the pipeline", developed as part of the project.

6.3. The pipe-laying vessel must undergo tests prior to commencement of construction work, including testing of welding equipment and non-destructive testing methods, equipment for insulating and repairing welded pipe joints, tensioning devices, winches, control devices and control systems that ensure the movement of the vessel along the route and the laying of the pipeline to the design marks.

6.4. In shallow water sections of the route, the pipe-laying vessel must ensure that the pipeline is laid in an underwater trench within the tolerances determined by the project. To control the position of the vessel relative to the trench, scanning echo sounders and all-round scanning sonars should be used.

6.5. Before starting the laying of the pipeline in the trench, the underwater trench should be cleaned and control measurements should be made with the construction of the longitudinal profile of the trench. When pulling the pipeline along the seabed, it is necessary to perform calculations of traction forces and the stress state of the pipeline.

6.6. Traction means are selected according to the maximum design traction force, which in turn depends on the length of the pipeline being dragged, the coefficient of friction and the weight of the pipeline in water (negative buoyancy).

The values ​​of the coefficients of sliding friction should be assigned according to engineering surveys, taking into account the possibility of submerging the pipeline into the ground, the bearing capacity of the soil and the negative buoyancy of the pipeline.

6.7. To reduce traction during laying, pontoons can be installed on the pipeline, which reduce its negative buoyancy. Pontoons must be tested for strength against hydrostatic pressure and have devices for mechanical slinging.

6.8. Before laying the pipeline in the deep water section, it is necessary to perform calculations of the stress-strain state of the pipeline for the main technological processes:

start of laying

· continuous laying of the pipeline with a bend on S-shaped or J-shaped curve;

laying of the pipeline on the bottom during a storm and its rise;

Completion of installation work.

6.9. The laying of the pipeline should be carried out strictly in accordance with the construction organization project and the work execution project.

6.10. During the laying of the pipeline, the curvature of the pipeline and the stresses arising in the pipeline must be continuously monitored. The values ​​of these parameters should be determined on the basis of load and deformation calculations before the pipeline is laid.

7. Coastal protection measures

7.1. The fastening of the coastal slopes after laying the pipeline is carried out above the maximum design water level and must ensure the protection of the coastal slope from destruction under the influence of wave loads, rain and melt water.

7.2. In the course of coastal protection works, experience-tested environmentally friendly designs should be used, technological processes and work should be carried out in accordance with the requirements of the "Technical Specifications for the Construction of a Pipeline at the Crossing of the Coastline and Coastal Protection Measures".

8. Construction quality control

8.1. Construction quality control should be carried out by independent technical departments.

8.2. To achieve the required quality of construction work, it is necessary to ensure quality control of all technological operations for the manufacture and installation of the pipeline:

· the process of delivery of pipes from the manufacturer to the installation site must guarantee the absence of mechanical damage on the pipes;

· quality control of concreted pipes should be carried out in accordance with the technical requirements for the supply of concreted pipes;

· incoming pipes, welding materials (electrodes, flux, wire) must have Certificates that meet the requirements of the technical specifications for their supply;

· when welding pipes, it is necessary to carry out systematic step-by-step control over the welding process, visual inspection and measurement of welded joints and check all circumferential welds by non-destructive control methods;

· insulating materials intended for assembly joints of pipes should not have mechanical damage. Quality control of insulating coatings should include checking the continuity of the coating using flaw detectors.

8.3. Marine earth-moving equipment, pipe-laying barges and their service vessels must be equipped with an automatic orientation system designed to constantly monitor the planned position of these technical equipment during their operation.

8.4. The control of the depth of the pipeline in the ground should be carried out using telemetry methods, ultrasonic profilers or diving surveys after the pipeline is laid in the trench.

If the depth of the pipeline in the ground is insufficient, corrective measures are taken.

8.5. During the laying of the pipeline, it is necessary to control the main technological parameters (the position of the stinger, the tension of the pipeline, the speed of the pipe-laying vessel, etc.) for their compliance with the design data.

8.6. To control the state of the bottom and the position of the pipeline, it is necessary to periodically conduct a survey with the help of divers or underwater vehicles, which will reveal the actual location of the pipeline (erosion, sagging), as well as possible deformations of the bottom along the pipeline caused by waves or underwater currents in this area.

9. Cavity cleaning and testing

9.1. Offshore pipelines are subjected to hydrostatic testing after being laid on the seabed in accordance with the requirements of the "Specifications for Testing and Commissioning of the Offshore Gas Pipeline", developed as part of the project.

9.2. Preliminary testing of pipeline strings on shore is performed only if the project provides for the production of pipeline strings on shore and their laying in the sea by dragging methods towards the pipe-laying vessel.

9.3. Prior to hydrostatic testing, it is necessary to clean and control the internal cavity of the pipeline using pigs equipped with control devices.

9.4. The minimum pressure during hydrostatic strength tests is assumed to be 1.25 times higher than the design pressure. In this case, the hoop stresses in the pipe during the strength test should not exceed 0.96 of the yield strength of the pipe metal.

The holding time of the pipeline under the pressure of the hydrostatic test must be at least 8 hours.

The pipeline is considered to have passed the pressure test if no pressure drops were recorded during the last four hours of testing.

9.5. The tightness test of the offshore gas pipeline is carried out after a strength test and a decrease in the test pressure to the calculated value during the time necessary to inspect the pipeline.

9.6. Removal of water from the pipeline must be carried out with the passage of at least two (main and control) piston-separators under the pressure of compressed air or gas.

The results of removing water from the gas pipeline should be considered satisfactory if there is no water ahead of the control piston-separator and it left the gas pipeline intact. Otherwise, the passage of the control piston-separator through the pipeline must be repeated.

9.7. If the pipeline breaks or leaks during the test, the defect must be repaired and the offshore pipeline retested.

9.8. The offshore pipeline is put into operation after final cleaning and calibration of the internal cavity of the pipeline, initial diagnostics and filling of the pipeline with the transported product.

9.9. The results of the cavity cleaning and pipeline testing, as well as the removal of water from the pipeline, must be documented in acts in the approved form.

10. Environmental protection

10.1. In marine conditions, all types of work require a careful selection of technological processes, technical means and equipment that ensure the preservation of the ecological environment of the region. It is allowed to use only those technological processes that will ensure the minimum negative impact on the environment and its rapid recovery after the completion of the construction of the offshore gas pipeline system.

10.2. When designing an offshore gas pipeline system, all environmental protection measures must be included in a properly approved environmental impact assessment (EIA) plan.

10.3. When constructing a system of offshore gas pipelines, it is necessary to strictly comply with the environmental requirements of Russian standards. In water areas of commercial fishery importance, it is necessary to provide for measures for the conservation and restoration of biological and fish resources.

The dates for the start and end of underwater earthworks using hydromechanization or blasting are established taking into account the recommendations of the fisheries protection authorities, based on the timing of spawning, feeding, fish migration, as well as the development cycles of plankton and benthos in the coastal zone.

10.4. The EIA plan should include a set of design, construction and technological measures to ensure environmental protection during the construction and operation of the offshore gas pipeline system.

In the process of developing an EIA, the following factors are taken into account:

· initial data on natural conditions, background ecological state, biological resources of the water area, characterizing the natural state of the region;

· technological and design features of the offshore gas pipeline system;

· terms, technical solutions and technology for performing underwater technical works, a list of technical means used for construction;

· Assessment of the current and predicted state of the environment and ecological risk, indicating the sources of risk (technogenic impacts) and probable damages;

· basic environmental requirements, technical and technological solutions for environmental protection during the construction and operation of the offshore gas pipeline and measures for their implementation at the facility;

· measures to ensure control over the technical condition of the offshore gas pipeline system and prompt elimination of emergencies;

monitoring of the state of the environment in the region;

· the size of capital investments in environmental, social and compensation measures;

· Evaluation of the effectiveness of the envisaged environmental and socio-economic measures and compensations.

10.5. During the operation of the offshore gas pipeline system, it is necessary to predict the possibility of a pipeline rupture and product release with an assessment of the expected damage to the sea biota, taking into account the possible accumulation of fish (spawning, migration, feeding period) near the pipeline system site and to implement protective measures for the pipeline and the environment provided for such cases by the project.

10.6. To protect and preserve the natural environment in the sea area and in the coastal zone, it is necessary to organize constant supervision over compliance with environmental measures during the entire period of anthropogenic impact caused by the construction and operation of the offshore gas pipeline system.

Annex 1.
Mandatory.

Designations and units of measurement

D - nominal diameter of the pipeline, mm;

t - nominal thickness of the pipeline wall, mm;

s x - total longitudinal stresses, N / mm 2;

s y - total hoop stresses, N/mm 2 ;

t xy - tangential shear stresses, N/mm 2 ;

K - design coefficient of reliability, taken according to;

s t - the minimum value of the yield strength of pipe metal, adopted according to state standards and specifications for steel pipes, N / mm 2;

P - design internal pressure in the pipeline, N/mm 2 ;

Ro - external hydrostatic pressure, N / mm 2;

Px - drag force, N/m;

Рz - lifting force, N/m;

Ri - inertial force, N/m;

G - pipeline weight in water (negative buoyancy), N/m;

m - reliability factor, taken equal to 1.1;

f is the coefficient of friction;

Рс - calculated external hydrostatic pressure on the pipeline, taking into account the ovality of the pipe, N / mm 2;

Рсг - critical external pressure for a round pipe, N / mm 2;

Ru - external pressure on the pipeline, causing the fluidity of the material

pipes, N / mm 2;

PP - external hydrostatic pressure at which the pipe collapse that occurred earlier will spread, N / mm 2;

e o - allowable bending deformation for the pipeline;

e c - critical deformation of the bend, causing collapse as a result of pure bending of the pipe;

u- Poisson's ratio;

E - Young's modulus for pipe material, N / mm 2;

H - critical water depth, m;

g - acceleration of gravity, m / s 2;

r- density of sea water, kg/m 3 ;

U - ovality of the pipeline;

R - permissible radius of curvature of the pipeline when laying at great depths of the sea, m.

Technical terms and definitions

Offshore gas pipeline - a horizontal part of the pipeline system located below the water level, including the pipeline itself, electrochemical protection devices on it and other devices that ensure the transportation of gaseous hydrocarbons under a given technological regime.

Protected zone of coastal sections of the gas pipeline - sections of the main gas pipeline from coastal compressor stations to the water's edge and further along the seabed, at a distance of at least 500 m.

Pipe elements - details in the construction of the pipeline, such as flanges, tees, elbows, adapters and valves.

Weight Coating - a coating applied to a pipeline to provide it with negative buoyancy and protection against mechanical damage.

Negative pipeline buoyancy - downward force equal to the weight of the pipeline structure in air minus the weight of the water displaced in the volume of the pipeline immersed in it.

Minimum yield strength - the minimum yield strength specified in the certificate or standard to which the pipes are supplied.

In calculations, it is assumed that at the minimum yield strength, the total elongation does not exceed 0.2%.

Design pressure - pressure, taken as a permanent maximum pressure exerted by the transported medium on the pipeline during its operation and for which the pipeline system is designed.

pressure surge - accidental pressure caused by failure of the steady state flow in the piping system shall not exceed the design pressure by more than 10%.

Overpressure - the difference between two absolute pressures, external hydrostatic and internal.

Test pressure - normalized pressure at which the pipeline is tested before putting it into operation.

Leak test - hydraulic pressure test, which establishes the absence of leakage of the transported product.

Test of endurance - hydraulic pressure test, which establishes the structural strength of the pipeline.

Nominal pipe diameter - the outside diameter of the pipe specified in the standard to which the pipes are supplied.

Nominal wall thickness - pipe wall thickness specified in the standard to which pipes are supplied.

Offshore pipeline reliability - the ability of the pipeline to continuously transport the product in accordance with the parameters established by the project (pressure, flow, and others) for a specified period of operation under the established control and maintenance regime.

Permissible stresses - maximum total stresses in the pipeline (longitudinal, ring and tangential), allowed by the standards.

Burying the pipeline - the position of the pipeline below the natural level of the seabed.

Depth value - the difference between the levels of the upper generatrix of the pipeline and the natural level of the seabed.

The length of the sagging section of the pipeline - the length of the pipeline that is not in contact with the seabed or with support devices.

Offshore pipeline laying - a complex of technological processes for the manufacture, laying and deepening of the offshore pipeline.

Appendix 3
Recommended.

Regulatory documents used in
development of these rules and regulations:

1. SNiP 10-01-94. "The system of normative documents in construction. Basic provisions" / Ministry of Construction of Russia. Moscow: GP TsPP , 1994

2. SNiP 2.05.06-85 *. "Main pipelines" / Gosstroy. M.: CITP Gosstroy, 1997

3. SNiP III-42-80 *. "Rules for the production and acceptance of work. Main pipelines" / Gosstroy. Moscow: Stroyizdat, 1997

4. SNiP 2.06.04-82*. "Loads and impacts on hydraulic structures (wave, ice and ships)" / Gosstroy. M.: CITP Gosstroy, 1995

5. "Safety Rules for the Exploration and Development of Oil and Gas Fields on the Continental Shelf of the USSR", M.: "Nedra", 1990;

6. "Safety regulations for the construction of main pipelines". M.: "Nedra", 1982;

7. "Rules for the technical operation of main gas pipelines", M.: "Nedra", 1989;

8. US Standard "Design, construction, operation and repair of offshore pipelines for hydrocarbons", AR I - 1111. Practical recommendations. 1993.

9. Norwegian Standard "Det Norske Veritas" (DNV) "Regulations for Subsea Pipeline Systems", 1996

10. British Standard S 8010. "Practical guide for the design, construction and installation of pipelines. Subsea pipelines". Parts 1, 2 and 3, 1993

11. API 5 L. "US specification for steel pipes". 1995

12. API 6 D . "US Specification for Pipe Fittings (Valves, Plugs and Check Valves)". 1995

13. US Standard ASME B 31.8. "Regulations for Gas Transportation and Distribution Pipeline Systems", 1996

14. US standard MSS -SP - 44. "Steel flanges for pipelines", 1990.

15. International standard ISO 9000 "Quality management and quality assurance", 1996

= Post prepared in the interests of Stroygazmontazh Group of Companies =

We are a generation that was born in the age of a technological breakthrough, and often do not even imagine what is behind the achievements of civilization. Of course, in general terms, everyone knows that water flows through pipes in the ground, the GPS signal comes from a satellite in space, and giant stations generate electricity. But did we understand what it cost to create all this?

Previously, i , and . Now we will talk about an unusual object that was built by the Rotenberg company. We know that not only sports facilities were built for the Games in Sochi, but also infrastructure elements. Often built from scratch and for the first time: it is not for nothing that a film about one of the most complex and impressive infrastructure facilities is called " Nobody ever"We are talking about the Dzhubga - Lazarevskoye - Sochi gas pipeline. Its uniqueness is that 90% of the main route (and this is more than 150 km) runs along the bottom of the Black Sea along the coastal strip at a depth of up to 80 meters. This decision made it possible to avoid any -or the impact of construction on the Black Sea coast.

As I have already said, the main part of the gas pipeline runs along the bottom of the Black Sea at a distance of five kilometers from the coast. At the very beginning, end and several sections along the way, the route goes outside and connects with gas distribution points. In these sections, gas is sent along various routes to the consumer. And he comes, in turn, from Yamal along other main routes. In other words, before reaching Sochi, gas travels thousands of kilometers from north to south:

The gas distribution point (GRP) "Kudepsta" is located on the top of the mountain. A main pipe "cuts" into the land from the sea and rises up. According to the builders, the inclined drilling method was used to create this section. They did not lay the route using the usual trench method, so that, again, not to harm the environment:

4.

However, the most interesting thing is how the main highway was built. All work took place at sea. Huge pipes half a meter in diameter made of heavy-duty alloy were reinforced with a layer of concrete, welded right on the ship, and then lowered into the sea:

Before laying the gas pipeline, submariners walked along the route of the pipe and discovered two minefields left after the Second World War:

The most difficult construction process was the joining of two pipes - the main "thread" that went along the sea and the land section. Docking also took place at sea and took three days. This required the coordinated work of the entire team that worked on the construction of the gas pipeline:

Today, the result of their work is hidden by 80 meters of water, and this unique experience is reminiscent of the new gas distribution point in Kudepsta, which increased the gas capacity of the entire Sochi region and its environs.

I must say that before the construction of a new gas pipeline, Sochi already had gas. At the same time, the share of gasification of the region did not exceed three percent. This is catastrophically small for life and, of course, would not provide the capacities necessary for the Olympics. In addition, in the event of accidents or failures, the entire coast would be left without fuel (suffice it to recall the story of the blackout in the Crimea).

Let's take a look at hydraulic fracturing and see how it works. Before you get there, you must go through the checkpoint and check. Being the most important infrastructure point, the GRP is guarded around the clock by several armed people:

8.

Passage inside is possible only accompanied by the head of the section and in agreement with the top management:

9.

Along the entire perimeter there are cameras with motion sensors:

10.

So, hydraulic fracturing is a point of gas distribution from the main main pipe. Here, the pressure is reduced and the gas goes to small gas distribution stations, which, in turn, send it to end consumers:

11.

The head of the section says that this is one of several parts of a multi-kilometer long pipe that goes outside:

12.

13.

It seems that the site "smells of gas", but it is not. The air smells of an odorant - a special composition that is added to the gas so that it acquires an odor (the gas itself has neither color nor odor):

14.

Odorant capacity:

15.

16.

After the pressure of the gas has decreased and a "smell" has been added to it, it spreads into several branches.

17.

Workers are planting fruit trees near the hydraulic fracturing station:

18.

In total, the Kudep point sends fuel to 11 stations. Here it is important to clarify that the gas pipeline is connected to the already existing Maikop line. This has its own meaning: if earlier an accident or preventive work occurred at some site, all the following points remained without gas. And now gas can circulate in two directions, ensuring the uninterrupted operation of the entire Sochi region:

19.

20.

The most important recipient of gas is the Adler TPP, about which I

The pipeline transport of Russia, which has almost 100 years of history, is the largest in the world. However, offshore pipelines (MT) have been used relatively recently. Offshore sections of gas pipelines were built and put into operation: North European (Nord Stream or NEGP) in the Baltic Sea, Blue Stream and Tuapse-Dzhubga in the Black Sea. Offshore oil pipelines of relatively short length are available in the Pechersk Sea (the offloading pipeline of the Varandey oil terminal), in the Baltic (D-6 field) on the Sakhalin shelf. MTs from the Shtokman gas condensate field in the Barents Sea and the Kirinskoye gas condensate field on the shelf of Sakhalin Island, South Stream in the Black Sea are at the design stage. In the future, with the development of work on the Arctic shelf, a significant increase in the number of MTs should be expected. The operation of MT, in relation to the operation of pipelines on land, has certain specifics, which are not sufficiently reflected in the regulatory documentation in force in the Russian Federation. The issues of ensuring the safe operation of these pipelines are currently being addressed mainly on the basis of projects focused mainly on in-line diagnostics. This principle does not meet modern requirements for the reliability and safety of hazardous production facilities. Only a systematic approach focused on the full-scale implementation of the task of monitoring the MT in real time, as well as the timely and high-quality performance of surveys, maintenance and repair work can guarantee the safe operation of the MT in the Arctic shelf. What steps need to be taken today to ensure this approach?

Features of offshore pipelines

During the design and construction, the reliability and safety of MT are provided according to increased requirements, in relation to those laid on land. This is caused by special (marine) conditions, such as a rather aggressive marine environment, underwater location, increased length without intermediate compressor stations, the effects of sea waves, wind and currents, seismicity, complex bottom topography, limited possibilities for preparing and monitoring the route, difficulty or impossibility implementation of the maintenance and repair procedures standard for main gas pipelines, etc.

As special measures to ensure the safety of MT, the following can be indicated:

1. installation along the MT route of protected zones (at a distance of up to 500 m from the axis of the pipeline) with a special regime of navigation and economic activity, determined at the federal level;
2. ensuring protection of MT from corrosion, which largely determines its reliability and safety, for the entire period of its operation and only in a complex way (with external and internal coatings and cathodic protection means);
3. the use of insulating joints in the design of the MT with a system of protection against corrosion (flange or coupling) from land areas;
4. when designing the MT, all possible impacts on the pipeline that may require additional protection are taken into account, namely:

The occurrence and spread of cracking or collapse of pipes and welds during installation or operation;

Loss of mechanical properties of pipe steel;

Unacceptably large pipeline spans at the bottom;

seabed erosion;

Striking the pipeline with anchors of ships or fishing trawls;

Seismic impacts;

Violation of the technological regime of gas transportation.

1. analysis of permissible spans and stability of the pipeline on the seabed, as well as calculation of nozzles - limiters of the avalanche collapse of the pipeline during its laying at great depths of the sea, when designing the MT;
2. deepening of the MP into the bottom in the areas of its landfall below the predicted depth of erosion of the bottom of the water area or onshore section for the entire period of operation of the offshore pipeline;
3. laying of MT on the surface of the seabed only if its design position is ensured during the entire period of operation (the possibility of its ascent or movement under the influence of external loads or damage by fishing trawls or vessel anchors is excluded), if necessary, the bottom of the water area is preliminarily prepared or the pipeline is laid in a trench ;
4. selection of the method of protection of MT depending on local environmental conditions and the degree of potential threat of each impact on the gas pipeline;
5. design of MT free from obstacles to the flow of the transported product (in the case of the use of artificial bending curves or fittings, their radius is assumed to be at least 10 pipeline diameters, which is sufficient for the free passage of treatment and control devices).

To ensure the safety of hydrocarbon transportation and reduce risk, the most modern achievements in the field of their construction, increased industrial safety requirements, high-quality pipes, welding and insulating materials, control systems, etc. are used in the design and construction of underwater pipelines. This circumstance objectively creates conditions for improving the reliability and safety of MPs, which is confirmed by the absence of accidents at all MPs put into operation in our country. However, the accident rate at offshore pipelines is a real fact and must be taken into account in the design, construction and operation of each MP.

Accidents at offshore pipelines

Data on accidents on offshore pipelines are quite widely presented in available sources of information. For example, they are published by the U.S. Department of Transportation's Office of Pipeline Safety (OPS) (oil, gas pipelines) as well as relevant organizations in the European Community. Based on the analysis of available data on approximately 700 cases of emergency depressurization of underwater pipelines (over a period of approximately 40 years), the main causes of their destruction were identified.

Distribution of the total number of destructions of underwater pipelines depending on the causes that caused them

The dominant causes of emergency situations are: corrosion - 50%, mechanical damage (impact of anchors, trawls) of auxiliary vessels and construction barges - 20% and damage caused by storms, bottom erosion - 12%. At the same time, most of the incidents occurred at the MT sections in the immediate vicinity of the platforms (within ~15.0 m), including on risers.

Based on the analysis of statistical data on the accident rate of offshore pipelines, it was found that, taking into account the measures taken to improve the reliability and safety of MT, the intensity of accidents at offshore pipelines has been constantly decreasing and is currently in the range of 0.02 - 0.03 accidents per year per 1000 km of their length.

For comparison, in the initial period of MT use (70s - years of the last century), the accident rate on offshore pipelines in the Gulf of Mexico was 0.2 accidents/year/1000 km of pipelines and 0.3 accidents/year/1000 km in the North Sea.

For comparison, in Russia the average accident rate is 0.17 accidents/year/1000 km for gas pipelines and 0.25 accidents/year/1000 km for oil pipelines.

During the operation of MT, despite the safety measures taken, there are real threats of damage or malfunction. These threats include pipeline defects, abnormal technological processes and regimes, man-made hazards, processes and phenomena in the geological environment, natural-climatic and geological factors, actions of third parties, scientific, industrial, military activities in the areas where the MT is located and other reasons.

Degree of risk of offshore pipeline accidents

Offshore pipeline accidents pose a risk of disturbing the ecological balance of the marine and geological environments in the areas of their use. The degree of danger of accidents increases significantly in the Arctic and Far Eastern seas of Russia, which are characterized by a low level of intensity of natural biological treatment, which in the event of accidental oil spills can lead to long-term pollution of sea water and bottom sediments.

In the event of an accident at an offshore pipeline, environmental damage will be determined by the amount of payments for excess environmental pollution and the cost of work to localize and eliminate the emergency spill. In offshore outflow conditions, due to the lack of a reliable leak detection system, as well as the complexity of oil spill response at sea, leaks with significantly higher values ​​than the average for existing onshore pipelines can be expected.

The reality of MT accidents, the degree of their danger, not much experience and possible risks of MT operation require adequate safety measures, which, in accordance with the requirements of the Federal Law of December 27, 2002 No. 184-FZ "On Technical Regulation", must be reflected, first of all, in approaches to the organization of MT operation.

Analysis of foreign experience in regulating the operation of offshore gas pipelines

Abroad, rather strict regulation of the operation of offshore pipelines has been established. The main documents from among the generally recognized international standards (published in the USA, Great Britain, Norway, the Netherlands, etc.) are indicated in the table.

In Europe, the regulation of the operation of offshore gas pipelines is implemented in the form of European Union Directives, which are approved by the members of the European Union. At the same time, the method of references to the current special regulatory documents on the main sea pipeline transport, which have received a positive assessment based on the results of long-term use (about 20 standards of the ISO series, standards of the USA, Norway, Canada, etc.), is widely used, such as:

API - 1111 "Design, construction, operation and repair of offshore pipelines for hydrocarbons", Practical recommendations. 1993 (US standard);

Det Norske Veritas" (DNV) "Regulations for Subsea Pipeline Systems", 1996 (Norwegian standard);

BS 8010. "Practical guide for the design, construction and laying of pipelines. Subsea pipelines". Parts 1, 2 and 3, 1993 (British Standard);

US Standard ASME B 31.8 "Regulations for Gas Transportation and Distribution Piping Systems", 1996;

US standard MSS -SP - 44 "Steel flanges for pipelines", 1990.

ASME B31.4-2006 "Pipeline systems for the transport of liquid hydrocarbons and other liquids";

ASME B31.8-2003 Gas Piping Systems and Gas Distribution; -CAN-Z183-M86 "Oil and gas pipeline systems";

ASTM 96 "Abrasion resistance of pipeline coatings".

The most commonly used standards are Det Norske Veritas (DNV). In particular, on their basis, an offshore section of the NEGP was created and a gas pipeline from the Shtokman gas condensate field is being designed.

The DNV system of standards relates safety to the elimination of the threat of harm to personnel, property and / or the environment, and risk - to the amount of damage caused. This approach focuses on balancing operational and process risk management activities to strike a sustainable balance between security, functionality and cost.

The requirements apply to pipeline inspections and repairs. At the same time, the main provisions of inspections and control should be established, based on detailed programs, the principles of formation of which are reviewed in 5-10 years.

In accordance with section B 200 of the DNV standard, the pipeline system must necessarily be provided with current control (inspection) during the operation. DNV standards prescribe structural survey of offshore pipelines and detection of defects (Section 10, item B, E DNV-OS-F-101), inspection and control of external and internal corrosion (Section 10, item C, D DNV-OS- F-101).

At the same time, "Parameters that can threaten the operability of the pipeline system must be monitored and evaluated at such a frequency as to allow corrective action to be taken before the system is damaged."

In general, the provisions and requirements set forth in the DNV standards are advisory in nature and do not contain specific provisions on the technique and technology for their solution.

Regulatory regulation of the operation of offshore pipelines in the Russian Federation

Based on the results of the review and analysis of the current regulatory framework in terms of the requirements of federal authorities and supervisory authorities for the organization and performance of work on the survey, operation and repair of offshore sections of gas pipelines, the following can be noted.

1. Currently, the entire existing regulatory framework for construction is being updated by updating SNiP and GOST, introducing European Union standards, as well as creating a unified regulatory framework for the Customs Union of Russia, Belarus and Kazakhstan and the EurAsEC.

2. Pipeline operators have the opportunity to form their own regulatory framework that does not contradict federal legislation, both by developing new documents and by recognizing existing regulatory documents - Russian and international.

3. The Russian Federation directively establishes general requirements for ensuring the safety of offshore pipeline transport of oil and gas through the appropriate organization and procedure for carrying out work on their examination, operation and repair. There is no detailed regulatory and technical documentation regulating the organization, conduct and control of these works at the federal level, since it is assumed that it will be developed at the level of organizations and enterprises.

4. The legal basis for the operation of MPs is the Federal Law No. 187-FZ dated November 30, 1995 and the Decree of the Government of the Russian Federation dated January 19, 2000 No. 44. In accordance with these documents, the MP operation system must be created and function in compliance with the requirements provided for by water legislation , and in the manner established by the Government of the Russian Federation, as well as on the basis of the regulatory and technical documentation (NTD) in force in the Russian Federation, the internal regulatory documentation of the EO (the EO branch), as well as international standards recognized in the Russian Federation.

5. In the Russian Federation, in the field of design, construction and operation of offshore pipelines, the regulatory documents indicated in the table are applied. International standards are widely used in practice:

ISO 13623, ISO 13628, ISO 14723-2003;

DNV standards, including the Rules for the Planning and Execution of Offshore Operations;

CAN/CSA-S475-93 (Canadian Standards Association) standards. Maritime operations. Marine structures;

German Lloyd. Rules for classification and construction. III. Marine technology.

In addition to those listed in the table, there are about 70 other regulatory documents related to various aspects of the MT life cycle.

6. The main document in force at the state level is GOST R 54382-2011 Oil and gas industry. Subsea pipeline systems. General technical requirements (hereinafter - GOST), which establishes requirements and rules for the design, manufacture, construction, testing, commissioning, operation, maintenance, re-examination and liquidation of underwater offshore pipeline systems, as well as requirements for materials for their manufacture. GOST is a translation from English into Russian of the Norwegian standard DNV-OS-F101-2000 (Oil and gas industry. Submarine pipeline systems. General requirements), establishes safety requirements for subsea pipeline systems by defining minimum requirements for design, materials, manufacture, construction testing, commissioning, operation, maintenance, recertification and disposal, and is in good agreement with ISO 13623, which establishes functional requirements for offshore pipelines (with some differences).

GOST requires that the parameters that affect the performance of the pipeline system are monitored and evaluated. At the same time, the frequency of monitoring or inspections should be such that the pipeline system is not endangered due to any deterioration in performance, wear and tear that may occur between two successive intervals (the frequency should ensure that the failure can be corrected in a timely manner). It is stated that if visual inspection or simple measurements are not practical or reliable, and available design methods and experience are not sufficient to reliably predict system performance, instrumentation of the piping system may be required.

GOST requirements for the operation, inspection, modification and repair of pipelines apply to the following elements:

Instructions;

Storage of operational documentation;

Measurements for technical and operational parameters:

Basic principles of control and monitoring;

Special checks;

Inspection of the pipeline configuration;

Periodic examinations;

Control and monitoring of external corrosion;

Pipelines and risers in the dive zone;

Control and monitoring of internal corrosion;

Corrosion control;

Corrosion monitoring;

Defects and repairs.

However, these requirements are of a general nature and for practical use they need to be detailed, which is advisable to implement within the framework of the new standard (hereinafter referred to as the Standard).

It should be noted that the selective application of international requirements is not always possible due to the heterogeneity of approaches in Russia and abroad to the regulation of safety at the same facilities.

General approach to the formation of the Standard

Currently, in the Russian Federation, technical regulation, including in the field of operation of main gas pipelines, is carried out in accordance with the Federal Law of December 27, 2002 No. 184-FZ "On Technical Regulation", which fundamentally changed the domestic standardization system. The novelty of this system is as follows:

A 3-level system for constructing regulatory documentation is being created, in which only the requirements of the upper (directive) level, which are established by special technical regulations (STR) of the Russian Federation, are mandatory;

State (national) standards are voluntary;

Corporate standards are valid only among the organizations that have approved them;

Allowed the use of international standards as a basis for the development of national standards;

Responsibility for the safe operation of man-made facilities, including pipeline transport facilities, rests with their owners (customers).

Solving the problems of ensuring the safety of MT operation should take into account the requirements of domestic and foreign standards and link safety with the elimination of the threat of harm to personnel, property and / or the environment, and the risk - with the amount of damage caused. This approach should be oriented towards a balance of operational and technological risk management activities in order to find a sustainable balance between safety, functionality and cost. For this, the main provisions/principles for the operation of MP should be established, in particular, control, maintenance and repair of their elements, including inspections, inspections and surveys.

The standard should implement the provisions of the general concept of technical regulation, in relation to the object of its regulation and refer to the fundamental documents (organizational-methodical and general technical standard).

The standard should be developed on the basis of substantiated scientific and technical provisions aimed at reducing the risk and ensuring safety in the operation of MP and provide a modern level of organization and conduct of relevant work.

The standard should ensure the level of safety of MT operation, which should be perceived as a combination of industrial safety, environmental safety, protection against unauthorized interference and terrorist threats, labor protection, etc., not lower than onshore sites.

The standard should apply to the processes of operation, inspection, maintenance and repair of MPs laid on the continental shelf and in the inland seas of the Russian Federation.

The standard should establish (in a minimum volume) general provisions, basic guidelines, recommendations and mandatory general technical requirements, the most important norms and rules for processes, procedures, works and operations related to the operation, inspections, maintenance and repairs of MT. The requirements of the Standard should not prevent initiatives to introduce modern methods and technical means, optimize technologies and organizational processes, and carry out work on the operation of MPs based on good maritime practice.

The standard should contain both safety requirements that take into account the hazards specific to the operation of MT, and administrative provisions, which include the rules for planning, organizing, preparing, conducting, controlling, accepting various works and the rules for confirming the conformity of equipment used for operation, inspection and repair corresponding to the requirements. Main threats to MT security

An analysis of the available information on the experience of operating offshore pipeline systems for the transportation of hydrocarbons shows that the components of the overall safety threat are:

Natural and climatic factors;

Processes and phenomena in the geological environment;

Structural and technological defects of the pipeline;

emergency technological situations;

Technogenic hazards (explosive objects; flooded chemical weapons and sunken objects);

Activities at sea;

Actions of third parties.

According to available data, external threats (from the outside of the pipeline) prevail over internal ones (inside the pipeline), both in terms of the overall accident rate and the degree of their danger. In this regard, priority was given to the issues of MGP surveys to ensure the diagnosis of its technical condition.

The standard should encourage the manifestation of personnel initiatives to introduce modern methods and technical means of operating, surveying and repairing marine ships, as well as to optimize relevant technologies and organizational processes based on good maritime practice.

The standard should provide:

Protection of human life and health, property, as well as prevention of actions that mislead consumers (users) regarding the purpose and safety of MT;

Concentration in a single document of the main requirements of legal and regulatory documents in force in the field of operation, surveys, maintenance and repairs of MT;

Elimination of gaps in the regulation of activities for the operation, inspection, maintenance and repair of MP.

Particular attention should be paid to the requirements for inspections and repairs of MPs relating to special processes, procedures, works, marine operations, ships and equipment.

The standard should be developed on the basis of substantiated scientific and technical provisions aimed at reducing the risk and ensuring safety during the operation of MP and should provide a modern level of organization and conduct of relevant work.

All main provisions, norms, requirements and rules of the Standard must be harmonized with their analogues of the existing Russian and foreign regulatory framework.

The requirements for offshore work (inspections and repairs of MT, offshore operations) should be based on the use of practical experience in the development and implementation of "offshore projects" in our country, as well as taking into account the applicable norms, rules and requirements of the RMRS, Norwegian (DNV) and American (API ) standards, recommendations of the Canadian Standards Association and other sources of information.

When developing these technical conditions and specifications, it is required to use scientific and technical documentation, including generally recognized international standards, such as API 1111 (1993), DNV (1996) and BS 8010 (1993), as well as the results of scientific research on this issue.

The standard should be developed on the basis of an integrated approach to the organization and implementation of all work on the operation of MP, including repairs. At the same time, it is important to ensure the possibility of maintaining constant feedback to adjust and supplement the requirements.

The standard should establish the following basic principles for the operation of MT:

1. MT operation should be aimed at preventing failures and reducing the severity of their consequences.
2. There are no unified (universal) rules for the operation of MT. For each MT, individual rules must be established, taking into account the peculiarities of its use, maintenance and repairs. Initially established rules should be periodically reviewed and, if necessary, revised, taking into account the accumulated operating experience of the MP. The effective development of the rules can and should be ensured by the personnel directly serving the MT.
3. A significant part of probable MT failures is not related to the age of the gas pipeline and its means of operation, but depends on the quality of construction, use and maintenance.
4. The operation of the MP should be based on a system of special measures to ensure a given level of reliability of the gas pipeline based on a unified system of expert diagnostic maintenance, which provides for the maintenance and repair of its linear part according to the actual condition based on the diagnosis and monitoring of the technical condition of the gas pipeline and its subsoil.
5. Principal decisions on the maintenance and repair of MT should be justified by assessing the risk of adverse development of initiating events (reasons for these decisions).
6. Repair planning should be accompanied by the identification of conditions prior to failures and the prediction of the moments of failures.
7. Capital repairs should be, if possible, excluded by effective control and monitoring of the process of using MPs, conducting timely surveys, diagnostics and forecasting changes in the technical condition of MPs, repair and maintenance and repair and restoration work on problem areas of the gas pipeline.
8. Maintenance personnel should be focused on the need to generate reasonable proposals aimed at ensuring the reliability and safety of MT operation, as well as reducing operational risks.
9. Taking into account that each specific MT has the peculiarities of local conditions, design and construction solutions, instructions of manufacturers and suppliers of equipment and materials used in the MT, detailed requirements for the operation, inspection and repair of MT should be developed and recorded in job and production instructions, drawings, diagrams and other documents.

The standard should be developed on the basis of the current NTD in the Russian Federation, taking into account design solutions for commissioned MTs, current domestic and international experience in surveying, operating and repairing offshore pipelines and other underwater stationary facilities, as well as using departmental regulatory documents, technical literature, R&D results.

To minimize the amount of regulatory requirements in the Standard, it is advisable to use the mechanism of references to well-known specifications, practical recommendations and standards.

It seems that the regulation of the operation of the MP should be established by a special state standard, for the development of which it is necessary to involve specialists with comprehensive experience and knowledge both in the field of design and operation of offshore underwater pipelines, and the methods and technical means used in this. It is especially important to take into account the experience of marine diving and underwater technical work on the inspection and repair of various underwater stationary objects.

Table - Regulatory documents in the field of design, construction and operation of offshore pipelines in force in the Russian Federation

International Documents

UNECE document "Guidelines and good practices for ensuring the operational reliability of pipelines";

ISO 13623-2009 "Oil and gas industry - Pipeline transportation systems";

ISO 5623 Petroleum and natural gas industries. Pipeline transportation systems (ISO 5623 Petroleum and natural gas industries - Pipeline transportation systems).

ISO 5623 Petroleum and natural gas industries. Pipeline transportation systems (ISO 5623 Petroleum and natural gas industries - Pipeline transportation systems)

ISO 21809 Surface coatings for buried or subsea pipelines used in pipeline transportation systems;

ISO 12944-6 "Corrosion protection of steel structures by protective paint systems"

GOST R 54382-2011 Oil and gas industry. Subsea pipeline systems. General technical requirements. (DNV-OS-F101-2000. Oil and gas industry. Submarine pipeline systems. General requirements).

ASME B31.4-2006 "Pipeline systems for the transport of liquid hydrocarbons and other liquids";

ASME B31.8-2003 Gas Piping Systems and Gas Distribution;

CAN-Z183-M86 "Oil and gas pipeline systems".

Departmental documents

VN 39-1.9-005-98 Standards for the design and construction of an offshore gas pipeline

The concept of technical regulation in JSC "Gazprom" (approved by the order of JSC "Gazprom" dated September 17, 2009 No. 302)

STO GAZPROM 2-3.7-050-2006 (DNV-OS-F101) Marine standard. Subsea pipeline systems

STO Gazprom 2-3.5-454-2010. organization standard. Rules for the operation of main gas pipelines (approved and put into effect by OAO Gazprom Order No. 50 dated May 24, 2010),

"Regulations on independent technical supervision and quality control of the construction of facilities of the Yamal-Europe gas transmission system"