Process solutions of the riser for pulsed gas extraction

Project Description

Working documentation has been developed for the facility "Gas pipeline outlet to AGRS" Zaluchye. " Inv. №000013961. Overhaul of GO at the Zaluchye GRS from 0 km to 1.17 km. Valdai LPU MG. "

Owner of detailed documentation -.

General designer -.

The right to design is granted to:

Type of construction - overhaul.

Working documentation is developed on the basis of:

- design tasks;

- technical requirements;

- technical report on engineering and geodetic, geotechnical surveys performed.

The purpose of the work is to restore the design parameters of the gas pipeline-discharge to the Zaluchye GRS in the scope of overhaul to meet the requirements of the NTD, ensure its safe operation and reliability of gas supply.

Main parameters of the section in question:

- diameter conditional MG "BelousovoLeningrad" DN1000;

- pressure: Pmax slave = 5.4 MPa;

- nominal diameter of GR on "Zaluchye" GRS: DN100;

- wall thickness: 4 mm;

- pressure: Pmax slave = 5.4 MPa;

- insulation coating - mastic (normal) ICBM;

- pipeline is laid underground;

- existing KU No. 3642.7 DN100 (above-ground installation);

- transported medium: natural gas;

- pipeline temperature: 010 ° С.

According to SNiP 2.05.0685 * by operating pressure the pipeline belongs to class I.

In accordance with Table 2 of SNiP 2.05.0685 *, the designed gas pipeline-outlet is classified as IV category (with the exception of certain areas where upgrading is provided in accordance with Table 3

SNiP 2.05.0685 *).

The technical solutions adopted in the working documentation comply with the requirements of environmental, sanitary hygiene, fire protection and other standards applicable in the territory of the Russian Federation, and ensure safe operation of the facility for life and health of people, subject to the measures provided for in the working drawings.

Description of the work area

Physical and geographical characteristics of the construction area

The work area is located in the Vyshnevolotsky district of the Tver region. The Tver region borders in the north - in the Vologda region, in the north-west - with Novgorod, in the east - with Yaroslavl, in the west - with Pskov, in the south - with Smolensk and in the southeast - with the Moscow regions.

Administratively, the site of work is located on the territory of the Vyshnevolotsky district of the Tver region. The region stretches 260 km from north to south and 450 km from west to east .

Climatic characteristics of the construction area

The construction area is located in the zone of temperate continental climate, which is characterized by relatively warm summers, moderately cold winters with stable snow cover, well-defined transitional seasons.

Climatic characteristics for the long-term period are given according to the data of the Tver weather station:

- absolute minimum air temperature minus 50 ° С;

- absolute maximum air temperature + 36 ° С;

- average temperature of the coldest month of the year (January) minus 10.5 ° С;

- average temperature of the warmest month of the year (July) + 17.3 ° С;

- average annual rainfall of 650 mm.

The largest (of the average) thickness of the snow cover in the open area is 40-60 cm.

Standard depth of seasonal freezing for man-made deposits -

1.7 m, for small sands - 1.4 m, for medium sands - 1.5 m.

Relief

Geomorphologically, the territory of the object is located within a hollow-wavy plain. The area of ​ ​ the site is relatively flat, with slight height differences. Absolute elevations of the surface of the studied area are within the range from 169.05 to 175.10 m.

Geological conditions of the construction area

Geologically, the study site is located within the Moscow syneclise, which is the largest ancient negative structure of the Russian platform.

Deposits of Ostashkovsky glaciation were installed on the territory of the survey region. According to a schematic map of the distribution of Quaternary deposits of the Moscow Syneclise, the survey site is located in the zone of development of water-glacial (fgl III os) complexes of Ostashkovsky age.

In the geological structure of the site within the depth of drilling 3.0 m, modern man-made formations and upper-quaternary water-glacial (fgl III os) deposits, represented by sands of small and medium size, medium density, wet and saturated with water, take part. The deposits are covered from above by a soil-plant layer with a thickness of 0.20 m.

Man-made deposits (tIV)

EGE-1 (t IV) - bulk soils: sands of small and medium size, brown, wet, with gravel and crushed stone. Marked everywhere under the soil-plant layer. The installed capacity is from 0.30 to 0.40 m, the roof of the layer is at a depth of 0.20 m (absolute. 170.30174.60 m).

Upper Quaternary Deposits (QIII)

Fluvioglacial deposits (fgl III)

EGE-2 (fgl III os) - small sands of medium density, heterogeneous, brown, wet and saturated with water, with gravel and pebbles up to 15%. The opened power is 0.701.50 m, the roof of the layer is at a depth of 0.50 m (abs.otm. 170.00173.60 m).

EGE + 3 (fgl III os) - sands of medium size, medium density, inhomogeneous, brown, wet and saturated with water, with gravel and pebbles up to 20%. The opened capacity is 1,002.50 m, the roof of the layer is at depths of 0.502.00 m (abs. 168.90174.20 m).

Corrosion aggressiveness to steel was determined in the laboratory by the ULPK1 device according to the average density of cathode current in accordance with GOST 9.6022005.

Corrosion aggressiveness of soils is evaluated:

- with respect to carbon and low alloy steel - medium;

- with respect to concrete of normal permeability W4 - non-aggressive ;

- in relation to lead cable cover, soils have medium degree of corrosion aggressiveness in terms of content of nitrate ions.

- in relation to the aluminum cable cover, soils have a high degree of corrosive aggressiveness in terms of the content of chloro-ions. (in accordance with Table 2.4 of GOST 9.6022005 [13]).

Hydrological characteristics of the construction area

Hydrogeological conditions of the drilling depth section are characterized by the presence of an aquifer confined to a complex of quaternary sediments.

Groundwater is confined to fluvioglacial sands of small and medium size (fgl III).

During the survey period (December 2012), groundwater with a free surface was fixed at depths from 0.9 to 1.3 m, at abs. elevations from 169.5 to 173.8 m. The waters are pressurized .

The aquifer is fed by infiltration of atmospheric precipitation.

Maximum levels in unfavorable periods of the year (periods of heavy snowmelt and liquid precipitation) can be expected at elevations close to the daily surface (abs. 174.80 m).

According to the results of chemical analysis of water samples taken at the site, in accordance with SNiP 2.03.1185, groundwater is non-aggressive with respect to concrete of normal permeability.

In relation to the lead cable cover, underground waters have a medium degree of corrosion aggressiveness in terms of total stiffness .

In relation to the aluminum cable shell, underground waters have a medium degree of corrosive aggressiveness in the content of chlorine ions.

Major overhaul solutions

Design Boundaries

The working documentation adopted a construction picket along the gas flow. The point on an axis of connection of a gas pipeline branch to MG BelousovoLeningrad is taken for the PK0+00. The end point, PK10 + 58, is a point on the axis of the gas pipeline, located 2.0 m opposite the gas stroke from the fence of the Zaluchye GRS.

Key Technical Solutions

In accordance with the Technical requirements and the main technological solutions, the working documentation provides for:

- replacement of the TSS 1020h159 T-connector in GO tie-in location to GRS "Zaluchye" to

MG BelousovoLeningrad;

- installation of DN1000 coils 2.0 m long on both sides of tee

TSS 1020h159 in GO tie-in location to GRS "Zaluchye" to MG BelousovoLeningrad;

- replacement of CP No. 3642.7 DN150 (underground installation) with redundancy of pulse gas;

- installation of automation and control equipment of crane units N 3642.7 and 4141.7;

- arrangement of crane assembly site;

- replacement of T-connector 108х108 in a junction of the duplicating insert and GO to GRS "Zaluchye";

- replacement of GO section to "Zaluchye" SGS in the amount of 1058.0 m;

- measures to re-lay the communication cable.

Removal works

The replacement of gas pipeline pipes to the Zaluchye gas pipeline should be carried out at a complete halt of gas transportation, disconnection and emptying of the gas pipeline in agreement with the Valdai LPU MG and Gazprom Transgaz St. Petersburg LLC.

Temporary gas supply of consumers to the Zaluchye GRS is provided for during the overhaul of the GO with the help of PAGZs (with gas reduction devices), based on the average daily gas consumption for the GRS according to the letter of Valdai LPU MG No. 437 dated 05.04.2013 (Appendix D).

Overhaul work is planned to be carried out during the period of lowest gas consumption - in June and August.

Calculation of the number of PPZs to provide gas to consumers of the Zaluchye GRS:

The average daily consumption of GRS (June-August) is 4700 m ³/day;

According to the letter of the Technological Transport Department of Gazprom Transgaz St. Petersburg LLC No. 02-10/964 dated 13.05.2013 (Appendix E), the capacity of the PAGZ is 2000 nm ³ (taking into account the emptying coefficient of 1800 nm ³).

The required number of flights per day will be: 4700/1800≈3. The distance from the AGNKS in Tver to the Zaluchye GRS is 170 km.

After cutting off the main line and emptying the section:

- remove signs of gas pipeline route fixation;

- remove the EHZ facilities;

- open the gas pipeline within the design limits;

- provide tightness of adjacent sections of the gas pipeline;

- to dismantle the existing T-connector on MG BelousovoLeningrad;

- remove KU fence No. 3642.7;

- remove the existing KU No. 3642.7;

- dismantle the gas pipeline-outlet section to the design boundaries;

- raise the gas pipeline to the edge of the trench;

- clean the gas pipeline from existing insulation;

- cut into single pipes and export to storage site.

Replacement of pipes, connectors

In accordance with the technical requirements of the working documentation, replacement of pipes with a total length of 1058.0 m is provided. Sections of category II, IV are subject to replacement .

Working documentation provides pipes:

- electric welded straight-joint DN1000 with a wall thickness of 12 mm made of steel of strength class K52, with a temporary resistance of 510 MPa and a yield strength of 360 MPa according to TU 1381012057578482005, manufactured by Vyksa Metallurgical Plant OJSC with external anti-corrosion three-layer polyethylene coating PEPk3N according to TU 1394015057578482011, allowed for use in Gazprom O;

- steel seamless hot-deformed steel 20 to

GOST 8732-78 *:

DN108 with wall thickness of 4 mm, NPEPk3, TU 1394007267046612012;

DN150 with wall thickness 6 mm without insulation;

DN50 with a wall thickness of 5 mm without insulation;

DN8 with a wall thickness of 3 mm without insulation.

- branch to MG BelousovoLeningrad to use the TSS 1020 (12K52) h159 (6K42) 5,60,75U T-connector to connection of the gas pipeline TU 1469014013950412007 Gas, with external anticorrosion coating of PK40 of TU 1469002013950412012, productions of CJSC Liskimontazhkonstruktsiya.

Use DSh 1020 (12K52) 5,60,75U Bottom to ensure tightness of adjacent gas pipeline sections and hydraulic tests

Gas TU 1469014013950412007, manufactured by Liskimontazhconstruction CJSC.

Apply OG Taps to artificial bend curves by

Gas TU 1469014013950412007, with external anticorrosion coating PK40

TU 1469002013950412012, manufactured by Liskimontazhconstruction CJSC.

Other connecting parts shall be provided with:

- tees as per GOST 173762001 *;

- taps as per GOST 173752001 *;

- transitions according to GOST 173782001 *;

- blankings as per GOST 173792001.

Pipes manufactured according to GOST 873278 * - GOST 873475 * shall comply with the requirements of item 4.2 of the section "Restrictions on selection of pipes "

STO Gazprom 2-2.1-131-2007 "Instruction on the use of steel pipes at Gazprom facilities.

The manufacturer of pipes and connectors according to national standards - according to STO Gazprom 2-2.1-131-2007 and the current register of pipe products of OAO Gazprom.

Welding works

Welding works shall be carried out in accordance with the requirements

STO Gazprom No. 2-2.2-136-2007 "Instruction on welding technologies in the construction and repair of field and main gas pipelines. Part I, "SNiP III4280 *,

STO Gazprom No. 142005 Standard Instruction for the Organization of Safe Fire Operations at Gazprom Facilities.

Pipe preparation, assembly, welding shall be carried out in accordance with the operational process maps of assembly and welding and meet the requirements

STO Gazprom 2-2.2-136-2007.

Welding of the newly installed pipes in the factory insulation and assembly of pipes in the raft should be carried out on the edge of the trench. Welding of joints is performed by manual electric arc welding. Upon completion of welding work, all welded joints shall be visually inspected and measured in the amount of 100 %.

After visual inspection and elimination of all unacceptable external defects, welded joints shall be inspected using non-destructive methods in accordance with STO Gazprom 2-2.4-083-2006.

On the crane assembly, the welded joints shall be subjected to 100% radiographic and 100% ultrasonic duplicate inspection.

The remaining welded joints shall be subjected to:

- radiographic control: process flags, butt joints of inserts ("coils"), joints with gas pipeline parts, at intersection with communications - in the amount of 100%; joints of category II - 20%; Category IV - 10%.

- ultrasonic inspection (additional): joints in category II areas in the amount of 80%; category IV - 90%.

- ultrasonic inspection (backup): process flags, butt joints of inserts ("coils"), joints with gas pipeline parts in the amount of 100%; at the intersection with communications - 25%.

Welding inspection results shall be documented in accordance with STO Gazprom 2-2.4-083-2006.

Insulation works

Isolate the welded joints of the factory and existing pipe using Transkor-Gaz manual application:

- TranscorGas primer, TU 5775005329892312010;

- bituminous polymer mastic "Transkor-Gaz" TU 5775004329892312010;

- grid of the TU 2296010002050092012 SSTB 3.4х3.4120 brand;

- a tape thermotaking seat "TERMAL" 450kh0,7mm TU 2245044821195872013.

Insulation of welded joints of pipes and connecting parts in factory insulation shall be performed with heat-shrinking cuffs: "Terma STMP - 1020," "Terma STMP - 159," "Terma STMP - 108" TU, 2245046821195872013 manufactured by LLC "Terma."

After installation, cover the above-ground sections of pipelines and equipment with a protective coating system SpetsProtekt 007/109 TU 2312015814331752012: in one layer with a primer SpetsProtekt 007 TU 23120078143317509 (60 μm) and two layers of enamel SpetsProtekt 109 TU 23120098143317509 (100 μm) in accordance with the corporate coloring of OAO Gazprom (Appendix

OAO Gazprom. Color solutions of process equipment of facilities

OAO Gazprom).

Insulation of underground sections of pipelines and connecting parts of pipelines without factory insulation, as well as the area of "ground air" transitions to a height of 500 mm from the ground surface shall be performed with two-component polyurethane coating "Scotchkote 352ht" in one layer.

After completion of construction perform quality control of insulation coating by damage seeker in accordance with GOST 5116498 item 6.2.9 and cathodic polarization method.

Insulation protection

On the designed section of the route there are gravel-pebble soils (IGE2, EGE-3). In accordance with item 5.7 of SniP 2.05.0685 *, the working documentation provides for protection of the insulation coating by filling the gas pipeline for a thickness of 0.1 m and filling the gas pipeline for a thickness of 0.2 m above the upper generatrix of the pipe using a bucket crusher.

Replacement of shut-off valves and equipment

In accordance with the technical requirements of the working documentation, it is provided to replace the existing KU No. 3642.7 with redundant pulse gas. The crane unit is located on the GO to "Zaluchiye" SG PC0 + 03 .

The following are accepted as shut-off valves:

1. Ball cranes:

- 11ls (6) 769p7 DN150, PN80 TU 3742004862326362010, underground, for welding, with pneumatic hydraulic drive with EPUU6 (24V), manufactured by LLC Tsimlyansk Machine-Building Plant, is provided for the replacement of crane No. 3642.7;

- KSH1.150630026 DN50, PN63 TU 3742008979654252007, above-ground, for welding, with manual drive, manufactured by Vostochnaya Armaturnaya Company LLC, is provided on the overpressure relief line from the receiver, as well as on the risers of pulsed gas extraction and routing.

2. Demountable ball coupling valve 10M.55.00.05.U DN10 PN55

TU 37 4220001 12673402-98, manufactured by PhF LLC "Yargazarmatura," is provided at the extraction risers;

For control of valve equipped with pneumatic hydraulic drive, system of pulse gas redundancy is made. Pulsed gas extraction is provided both before and after the valve, to the receiver with check valve at the inlet.

The gas extraction riser consists of the following elements: two shut-off ball cranes DN50 with manual drive and three branch pipes with cranes with ball coupling disassembling YGT 10M.55.00.05.U .

Receiver with length of 2.09 m and diameter of 159x6 mm is selected on condition of provision of volume of pulse gas required for double switching of controlled shutoff valves .

The pulsed gas flow riser consists of one hand-operated shut-off ball valve DN50 and three branch pipes with cranes with ball coupling disassembling YaGT 10M.55.00.05.U.

For cleaning and drying of pulse gas the filter-dryer of pulse gas "Ferrum80.75" TU 36830012154126799, production is used

LLC Ferrum.

To relieve excess pressure from the receiver, a DN50 pipeline is provided with one manually operated DN50 shutoff ball valve, as well as a tip with a self-throwing factory cover of NPSK Metallostrokonstruction CJSC.

Seal tightness of all shutoff valves - by class A (GOST R 548082011).

All used equipment, products and materials have the permission of the permanent commission of OAO Gazprom for their use.

Automation of technological solutions

As part of the facility for overhaul of GO at the Zaluchye GRS, on the basis of technical requirements, it is planned to replace the automation equipment of crane units N 3642.7 and 4141.7, which includes:

- KU telemechanization, on the basis of KP of "Main 2" telemechanics system, connected to the designed KP of TM MDS "Zaluchye";

- installation of pressure gauges and pressure sensors before and after cranes and on gas redundancy devices;

- installation of gas pipeline wall temperature sensors;

- installation of alarm sensors for opening the doors of the fences of crane platforms, the door of the block box, the door of the fence of the block box;

- installation of lightning protection barriers of external circuits of automation;

- installation of pulse gas lines.

- arrangement of cable routes within the crane assembly site;

Control of cranes and signalling of their position is provided by means of control unit EPUU6, with control signal 24V.

Installation and installation of automation devices and devices shall be carried out in accordance with SNiP 3.05.0785, PUE (edition 6, 7) and factory documentation for equipment.

Electrochemical protection

Working documentation provides for the following:

- installation of instrumentation of PVEC type, manufactured by LLC Technoprom along the route of the discharge gas pipeline in the amount of 2 pieces;

- insulation of the connection points of the electrochemical protection cable to the pipeline with polyethylene insulation coating should be made with the material "TermaR" and "TermaRZ";

- to measure polarization potential, control and measuring points should be equipped with copper-sulphate electrodes for comparison of long-term action of Enes3m type of Gas Equipment Plant LLC.

To ensure corrosion monitoring of instrumentation, installation of the corrosion process indicator IKP10012 manufactured by LLC "Gas Equipment Plant" is provided.

According to item 5.5 of GOST 5116498 * temporary protection of the gas pipeline-discharge at the Zaluchye GRS is not required, since the means of electrochemical protection of the pipeline will be connected no later than 3 months after laying and filling of the pipeline section.

Communication cable

Working documentation provides for re-laying of communication cable.

Prior to the beginning of works on re-laying of the gas pipeline line at the intersections, as well as along the TSS 2x1,2/4,4 + 2x4x0,9 + 4x0,9 cable re-laying routes, preliminary drilling shall be carried out for accurate determination of underground structures crossed by the routed communication cable.

Pits shall be 1.0 m long along the axis of the future trench. In the case where underground structures run parallel to the future route, pits shall be dug perpendicular to its axis every 20.0 m. The length of each pit shall exceed the width of the projected trench on each side not less than on

0.3 m.

The depth of the pits, if the wanted structures are not found, should exceed the depth of the trench by 0.2 m. The pits should be carried out in the presence of a representative of the organization operating underground structures.

On PC1 + 21 form the cable bay of process stock.

All works in the gas pipeline protection zone shall be performed by written permission of the Valdai LPU MG communication service department, in accordance with the "Rules for the Protection of Main Pipelines."

Construction solutions

In accordance with the technical requirements of the working documentation, the existing fence is to be replaced.

The fencing of the crane assembly site No. 3642.7 is provided for from metal sections AXIS SR. The fence is installed on a metal frame made of 159x4 pipes, GOST 1070491. Frame struts are arranged in pre-drilled wells and poured with concrete of class B15. A bracket for a protective visor is installed on top of the guard, which consists of three rows of barbed wire and a spiral safety barrier (SBB) "Egoz600." The height of the fence is 2.2 m. Underwater barriers are provided under the fence. Two wickets 1.0 m wide of DIRICKXESPASE products are provided in the fence. On the outside of the fence, install the sign "Gas! Entry is prohibited, "as well as an information plate indicating the operating organization, the organization's branch and the branch's telephone number and the sign" It is forbidden to use open fire and smoke "in accordance with STO Gazprom 2-3.5-454-2010. The sign "Do not approach! Protected Area "according to STO Gazprom 2-1.4-186-2008. Site dimensions 4000x3200 mm.

As well as in the detailed documentation it is provided:

- OP1 support. The support is designed for filter-dryer PN 80 "Ferrum80.75," made of profile 10P as per GOST 824097. The support is installed in a pre-drilled well on a crushed stone pad, followed by concreting.

- OP2 support. The support is developed under the crane spherical DN50 PN63 which is executed from pipe 100х100х4 in accordance with GOST 302452003 and from profile 10P on

GOST 824097. The support is installed in a pre-drilled well on a crushed stone pad, followed by concreting.

- Fill the crane assembly site with crushed stone to a height of 0.20 m.

Cleaning of internal cavity and testing of gas pipeline

Tests of the gas pipeline-outlet section and the crane assembly are carried out in order to detect defects and determine tightness.

Perform test works taking into account requirements

STO Gazprom 2-3.5-354-2009 according to special working instructions developed by the Contracting Organization agreed with the Customer, operating and design organization, OAO Gazprom monitoring and supervision organization and approved by the Chairman of the Commission.

The gas pipeline shall be tested in two stages:

Stage I - preliminary testing of elevated areas;

Phase II - final gas pipeline test.

Characteristics of tested areas, test parameters and organizational and technological diagram of cavity cleaning, tests, cavity drying are presented in the set 2012p819PIC.

The working documentation provides for hydraulic testing of the section with the length of:

- DN1000 - 5.0 m;

- DN150 - 4.0 m;

- DN100 - 1054.0 m.

The crane assembly shall be pre-tested on the track. Perform hydraulic tests of the crane unit for strength at Risp = 1, 1Prab for 2 hours.

Areas of increased category are tested after laying and backfilling at pressure Risp = 1, 25Prab = 6.75 MPa for 12 hours.

The following areas shall be tested:

- adjacent to the crane unit;

- adjacent to RRS.

At the final stage, it is required to perform a sequential test of the entire gas pipeline section for pressure Risp = 1, 1Prab = 5.94 MPa within 24 hours, after full readiness of high-grade sections.

Leak check shall be performed at pressure reduction to

Rrab = 5.4 MPa for 12 hours to inspect the crane assembly and the gas pipeline-outlet route.

The pipeline shall be deemed to have passed the strength test and the leak test if the pipe has not collapsed during the strength test and the pressure remains unchanged during the leak test and no leakage is detected.

Removal of moisture from the internal cavity of the gas pipeline

Cleaning of the cavity and displacement of water after hydraulic tests is provided for by blowing with compressed air supplied by a high-performance compressor unit without passing cleaning and separating pistons.

In order to prevent the formation of an explosive gas-air mixture when filling sections of the gas pipeline with gas, it should be filled with inert gas (nitrogen) with a concentration of at least 98%, TTR minus 20 ° C to excess pressure of 0.02 MPa before gas supply. It is allowed to fill the gas pipeline with gas without preliminary filling with nitrogen in certain cases, when ensuring safety measures, upon permission of OAO Gazprom.

Arrangement of gas pipeline route

In accordance with the requirements of the "Rules for the Protection of Main Pipelines" and STO Gazprom 2-3.5-454-2010, the following signs must be installed on the repaired section of the route:

- "Fixation of gas pipeline route on terrain" (9 pcs) at route turns, intersection with communications.

The appearance and information contained on the signs shall comply with the requirements of STO Gazprom 2-3.5-454-2010.