SNIP III-42-80S-en-trunk pipeline TARE

BUILDING CODES AND PRACTICES TRUNK PIPELINES SNIP III-42-80* OFFICIAL EDITION Moscow 1997 CONTENTS 1. GENERAL PROVISIONS.....................................................................................................3 3. EARTH-MOVING WORK .....................................................................................................6 4. ASSEMBLY, WELDING, AND QUALITY ASSURANCE OF WELDED PIPELINE JOINTS .8 GENERAL PROVISIONS .......................................................................................................................................... 8 WELDER QUALIFICATION CHECKING..................................................................................................................... 11 WELDED JOINT INSPECTION................................................................................................................................. 13 MANUFACTURE AND ASSEMBLY OF PIPELINE BEND CURVES ................................................................................. 16 5. TRANSPORTATION OF PIPES AND PIPE SECTIONS....................................................18 6. TRUNK PIPELINE CORROSION PROTECTION COATINGS ..........................................19 GENERAL PROVISIONS ........................................................................................................................................ 19 PIPELINE CLEANING AND PRIMING........................................................................................................................ 20 UNDERGROUND AND SURFACE (EMBANKMENT) PIPELINE PROTECTION AGAINST SOIL CORROSION......................... 20 ELEVATED PIPELINE PROTECTION AGAINST ATMOSPHERIC CORROSION ................................................................ 21 INSULATION COATING QUALITY ASSURANCE......................................................................................................... 22 7. TRENCH PIPELINE INSTALLATION.................................................................................22 GENERAL PROVISIONS ........................................................................................................................................ 22 PIPELINE BALLASTING AND ANCHORING ............................................................................................................... 23 8. CONSTRUCTION OF PHYSICAL OR ARTIFICIAL OBSTACLE CROSSINGS ................28 GENERAL PROVISIONS ........................................................................................................................................ 28 UNDERWATER CROSSINGS .................................................................................................................................. 28 MOTORWAY AND RAILROAD SUBSURFACE CROSSINGS ......................................................................................... 31 ELEVATED CROSSINGS AND INSTALLATION OF ELEVATED PIPELINES OVER CERTAIN AREAS ................................... 31 9. INSTALLATION OF PIPELINES IN SPECIFIC ENVIRONMENTS ....................................32 CONSTRUCTION OF SWAMP AND SLOUGH CROSSINGS.......................................................................................... 32 INSTALLATION OF PIPELINES IN MOUNTAINOUS TERRAIN ....................................................................................... 33 CONSTRUCTION OF PIPELINES IN TUNNELS .......................................................................................................... 35 CONSTRUCTION OF PIPELINES IN COLLAPSIBLE SOILS .......................................................................................... 35 CONSTRUCTION OF PIPELINES IN SAND WAVES, IRRIGATED LANDS AND DISPOSAL FIELDS ..................................... 36 CONSTRUCTION OF PIPELINES IN PERMAFROST SOILS .......................................................................................... 36 10. CATHODIC PROTECTION OF PIPELINES AGAINST UNDERGROUND CORROSION37 11. INTERNAL CLEANING AND TESTING OF PIPELINES..................................................39 GENERAL PROVISIONS ........................................................................................................................................ 39 INTERNAL CLEANING OF PIPELINES...................................................................................................................... 40 PIPELINE TESTING ............................................................................................................................................... 41 12. PROCESS COMMUNICATION LINES FOR MAIN PIPELINES ......................................46 13. ENVIRONMENT PROTECTION ......................................................................................48 Gosstroy USSR Building Codes and Practices SNIP III-42-80* Trunk Pipelines Instead of Chapter of SNIP III-�.10-72 1. GENERAL PROVISIONS 1.1. The practices contained in this chapter should be complied with when erecting new trunk pipelines as well as renovating existing ones and branch pipes therefrom that have a nominal diameter up to 1400 mm (inclusive) and an excessive fluid pressure within 10 MPa (100 kgf/cm2), all intended for transportation of: crude oil, oil products, commercial rock and casing head, natural and synthetic hydrocarbon gases from the regions of their production (from source and line booster pump stations), processing or storage to consuming points (tank farms, reloading storage areas, loading points, gas distribution stations at towns and inhabited locations, individual industrial and agricultural enterprises, and ports); condensed hydrocarbon gases (C3 and C4 cuts and mixtures thereof) as well as unstable gasolines and unstable condensates as well as other condensed hydrocarbons showing a saturated vapor pressure within 1.6 MPa (100 kgf/cm2) at a temperature of 45ºC from the regions of their production (from source and line booster pump stations), processing or storage to consuming points (tank farms, reloading storage areas, loading points, gas distribution stations at towns and inhabited locations, individual industrial and agricultural enterprises, and ports); Introduced by Minneftegasstroy USSR Approved by Resolution No. 67 of May 16, 1980, No. 67, of Gosstroy USSR Enforcement date: January 1, 1981 Official Edition site marks of the straight route segments at the river, ravine, road, and other natural and man-made obstacle crossings in a quantity of at least two on each side of a crossing within a visibility range; elevation benchmarks, installed at least each 5 km along the route, except for those installed at the water obstacle crossings (on both banks); an explanation note, mark arrangement outlines and drawings; a catalogue of geodetic base coordinates and station marks. When plotting a geodetic ranging base, the admissible root mean square errors are as follows: angular measurements, �2’; linear measurements, 1/1000; mark determinations, �50 mm. 2.2. Before the start in construction, a general construction and installation contractor should carry out the following work along the route: verify the geodetic ranging base to an accuracy of linear measurements of 1/500, that of angular measurements – 2’ at the least, and the data of leveling between bench marks to an accuracy of 50 mm per 1 km of the route. The route will be accepted from the customer pursuant to an acceptance deed if the measured line lengths deviate from the design ones by 1/300 at the most, the measured angles deviate from the design ones by 3’ at the most, and the sign marks as derived from the data of leveling between benchmarks deviate from the design data by 50 mm at the most; install additional signs (surveyor’s stakes, poles, etc.) along the route axis and construction zone boundaries; indicate in full size the horizontal curves of natural (elastic) bending at a spacing of 10 m and those of man-made bending at a spacing of 2 m; range out the base-line along the entire route and at its specific points (at the start, middle and end of curves, at the route crossings over underground service lines). As a rule, the sites of ranged-out points should be fixed by means of signs outside the construction and installation work area. Additional benchmarks should be installed at a spacing of 2 km along the route. 2.3. In addition to the requirements of SNIP 3.01.01-85*, prior to the start in basic construction and installation work, a general contractor should, if necessary, implement the following pre-construction work along the route in view of the specific construction environment: clean the allocated pipeline zone of any forests, shrubs, stumps, boulders; remove any separate trees and hanging-over rock parts and stones appearing outside the allocated zone but threatening to fall down into the allocated zone area; cut any steep longitudinal slopes; implement some protective activities against landfalls and landslides; implement some activities to minimize an earth freezing extent in a pipeline trench strip; erect some temporal roads, water conduct, water removal, as well as drainage facilities at access ways to and along the route as well as bridges and crossings over rivers, brooks, and ravines; protect access roads against any snowdrift; install some temporal storage areas or warehouses at the facilities to keep materials and equipment; install some temporal wharf and moorage points; prepare some temporal production floors and sites required for the implementation of welding, bitumen melting, and other types of work; build some temporal villages ensuring a required dwelling, sanitary, and cultural and social environment for the employees; prepare some helicopter landing areas; establish a dispatcher communication system; prepare some construction sites required for the implementation of construction and installation work towards the installation of pipeline crossings over natural and man-made obstacles and in the course of pipeline installation through tunnels, all provided with required temporal household and service rooms, structures, and roads; set up some water gauge stations outside the area of work performance towards the installation of pipeline crossings over water obstacles where a water gauge station is referenced by means of leveling to a pipeline route elevation survey and a national geodetic network; strip off a fertile ground layer and remove the same to a dump for temporal storage purposes according to Paragraph 13.8 hereof. 2.4. The route cleaning for a period of construction should be implemented within the allocated zone boundaries and in other locations as established by the project design. In winter, the cleaning should be implemented in two stages: prior to the start in basic work within a motor traffic and building machinery operation area, and immediately before the earth-moving machinery operation within a trench excavation area to a length ensuring the operation during a shift. 2.5. The stubbing in any dry area of the route should be implemented to the entire allocated zone width, and in any marshy area – within a future pipeline and cable trench strip only. It is necessary to saw off any trees at grade in the rest of the allocated zone. 2.6. An extent of grading work required for transportation purposes and building machinery travelling should be specified in the construction management design and finalized in the work performance design. 2.7. Any temporal road for building machinery and motor vehicle traffic should consist of one track expanded at the direction changing, turning, and double track sections (on the pipeline side opposite to a cable communication line route). Any double track section should be arranged within a direct visibility range though at a spacing of 600 m at the most. When erecting some winter roads, it should be generally sufficient to compact a snow cover with an ice crust laid over, freeze through an earth surface, and maintain a traffic track in good order. When erecting an operating some ice roads laid down rivers, brooks, and lakes, a carrying capacity of the ice should be identified and some work should be carried out to maintain an ice cover in operating order. A type, design, width of the roads and turn radii are fixed in the construction management design and finalized in the work performance design. 3. EARTH-MOVING WORK 3.1. Any trench dimensions and sections are fixed in the project design depending on a purpose and diameter of the pipelines, earth specifications, hydrogeologic and other conditions. 3.2. A trench bottom width should be at least D+300 mm in case of any pipeline with a diameter up to 700 mm (where D is a nominal pipeline diameter), and 1.5D in case of a pipeline with a diameter of 700 mm and more considering the following requirements: in case of pipelines with a diameter of 1200 and 1400 mm, when excavating any trench showing a slope of 1:0.5 at the most, it is permitted to reduce a trench bottom width to a value of D+500 mm; when excavating an earth by means of earth-moving machines, a trench width should be taken as equal to a cutting edge width of an excavating part of the earth-moving machine as accepted in the construction management design though equal to that mentioned above at the least; a trench bottom width within the curved segments made of pipe bends manufactured by means of forced bending should be twice as much as a width within the straight segments; a trench bottom width in case of the pipeline ballasting by means of burdening balances or fixing by means of anchoring devices should be equal to 2.2 D at the least; 3.3. A slope angle of the trenches should be accepted according to SNIP 3.02.01-87, and in case of those excavated in marshlands, according to Table 1. Table 1 Peat A slope angle of trenches excavated in marshland types I II III (high water content) Low degraded peat 1:0.75 1:1 - Well degraded peat 1:1 1:1.25 As per design In case of grounds containing silt and shifting sand both failing to preserve the slopes, the trenches are provided with supporting and water drainage arrangements. The types of supporting and water drainage arrangements in the specific environment should be established by the project design. 3.4. When excavating a trench by means of wheel-type trenching machines to achieve a smoother trench bottom surface at design marks and ensure the tight bearing of the installed pipeline against within the entire pipeline axis length the foot to a width of 3 m at the least, some leveling of the strip microtopography should be carried out in advance according to the design. 3.5. In case of marshlands, a trench should be excavated by means of backhoe shovels mounted on wider crawler tracks or crawler belts, dragline strippers or special machines. When laying a pipeline through marshlands using a fusion technique, it is expedient to excavate a trench and floating peat crust by means of blasting while applying some extended, concentrated or deep-hole charges. Hereby Paragraphs 3.6 and 3.7 are excluded. 3.8. To prevent any excavated trench section deformation as well as spoil congealing, a shift pace of insulation and installation work as well as that of earth-moving work should be equal. A gap required for the process purposes between the earth-moving as well as insulation and installation teams should be specified in the work performance design. As a rule, the backlog ground trench excavation (except for rock in summer) is prohibited. The loosening of rock by means of blasting should be implemented before the pipes have been delivered to the site, and the loosening of frozen grounds is permitted after the pipes have been laid out along the route. 3.9. When excavating a trench with the prior loosening of rock by means of drilling and blasting, any ground irregularities should be avoided by means of soft ground padding and consolidation. 3.10. The pipeline foots in rocks and frozen grounds should be graded using a soft ground layer of 10 cm thickness at the least above the protruding foot parts. 3.11. When installing any pipeline with a diameter of 1020 mm and more, the trench bottom leveling should be implemented within the entire route length; within the straight segments, at a spacing of 50 m; within the vertical curved elastic bending segments, at a spacing of 10 m; within the vertical curved forced bending segments, at a spacing of 2 m; when installing any pipeline with a diameter less than 1020 mm, the same should be implemented within the complicated route segments (vertical turning angles, rugged topography segments) as well as at the railroad and motor road, ravine, brook, river, gully and other obstacle crossings, in which case the special working drawings have to be prepared). 3.12. A trench bottom should be graded according to the design by the pipeline installation time. The pipeline installation in any trench deviating from the design is prohibited. 3.13*. The trench is backfilled immediately after a pipeline has been lowered in place and ballast balances or anchoring devices have been mounted if the pipeline ballasting is provided by the project design. The installation points of block valves, instrumentation tee- joints of cathodic protection stations are backfilled after the same have been installed and cathodic outputs have been welded. When a pipeline is backfilled with a spoil containing some frozen lumps, broken stones, gravel fragments, and other inclusions featuring a cross section of more than 50 mm, the insulation coating should be protected against any damage by means of a soft ground padded to a depth of 20 mm above the upper pipe surface or some protective coatings arranged according to the project design. Note: The restoration of trunk pipelines following any shrinkage (installation at design marks, design ballast restorations, extra spoil padding into trenches, embankment restorations, etc.) is implemented in the procedure as established by the Regulations of Contractual Agreements for Major Construction approved by Resolution No. 973 of December 24, 1969, of the USSR Council of Ministers. Table 2 Tolerance Tolerance (deviation) value, cm Half a trench bottom width to a ranging axis +20, -5 A deviation of marks in leveling a strip for wheel-type trenching machines -5 A deviation of trench bottom marks from design values: when excavating a ground by means of earth-moving machines -10 the same by means of drilling and blasting -20 A soft bed layer thickness at the trench bottom +10 A soft pad layer thickness above the pipe (in case of subsequent rock or frozen spoil backfilling) +10 A total backfill layer thickness above the pipeline +20 An embankment height +20, -5 3.14*. It is allowed, with a permission of the customer, to substitute both soft ground trench bottom covering and soft ground backfilling of a pipeline installed in rock, stony, crushed stony, dry lumpy and frozen grounds for some solid safe protection comprised of non-rotting environmental safe materials. 3.15. When constructing a trunk pipeline, any earth-moving work should be implemented in compliance with the tolerances indicated in Table 2. 4. ASSEMBLY, WELDING, AND QUALITY ASSURANCE OF WELDED PIPELINE JOINTS General Provisions 4.1. Before any pipe assembly and welding work, it is necessary to: perform a visual inspection of the pipe surfaces (while the pipes should be free of non- allowed defects as prescribed by the pipe procurement specifications); clean an internal pipe space of any ground, dirt, snow that penetrated inside; rectify or cut off deformed ends or pipe surface damages; clean the edges and adjacent internal and external pipe surfaces down to a bare metal to a width of 10 mm at the least. In case of butt fusion welding, a pipe end face and belt should be conditioned for the welding machine ramp shoes. 4.2. It is allowed to dress some smooth pi