SNIP 3.05.02-88 * - Gas supply

SNIP 3.05.02-88 * - Gas

building regulations

GAS SUPPLY

SNIP 3.05.02-88 *

Moscow 1995

developed by the Institute Giproniigaz Minzhilkomhoza RSFSR (. Candidate of Sciences VG Golik, Candidate of Technical Sciences Mikhail Kupriyanov ;... GP Chirchinskaya ) involving Mosgazniiproekta Moscow City, UkrNIIinzhproekta Minzhilkomhoza SSR, utilities Academy.KDPanfilov and associations Rosgazspetsstroy Minzhilkomhoza RSFSR trust Mosoblspetsstroy 3 Glavmosoblstroya.

INCLUDED SE "Rosstroygazifikatsiya".

prepared for approval by the Office of standardization and technical standards in the construction of the Ministry of Construction Russian ( SHishov NA).

SNIP 3.05.02-88 * is a reissue of SNIP 3.05.02-88 with change number 1, developed with the participation of GIPRONIIGAZ VNIIST and entered into force in the Russian Federation by the order of Ministry of Construction of Russia on June 4, 1992 № 135 and changenumber 2 , approved by decree Ministry of Construction of Russia on August 10, 1994 № 18-8.

sections, paragraphs, tables, formulas, in which the changes are marked in the present building regulations with an asterisk.

When using the standard document should take into account the changes approved construction standards and state standards and instilled published in the journal "Bulletin of construction machinery" and the information signs "state standards" Gosstandart of Russia.

State Building USSR Committee (Gosstroy USSR)	Construction norms and rules	SNIP 3.05.02-88 *
Gas	Instead SNIPIII -29-76 and CH 493-77

These rules and regulations apply to the construction of new and reconstruction of gas-supply systems, rules and regulations for the design of which is regulated by SNiP 2.04.08-87.

1. GENERAL PROVISIONS

1.1. During the construction of gas supply systems in addition to the requirements of development projects (hereinafter - projects) and the present rules and regulations must comply with the requirements of SNIP 3.01.01-85 *, SNIP 3.01.03-84, SNIP III-4-80 *, SNIP 3.01.04-87, as well as the "safety Regulations in the gas farm" and "Rules of design and safe operation of vessels working under pressure", approved by the State Technical Supervision.

Installation and testing of temporary pipelines and gas equipment should be carried out in accordance with the project and the requirements of these regulations.

Made Minzhilkomhozom RSFSR

approved Resolution State Construction Committee of the USSR on March 17, 1988 № 39

Term introduction into effect July 1, 1988

item 1.2 deleted.

1.3. * on pipe fittings, welding and insulation materials used in accordance with the project, must be certified by the manufacturers (or their copies certified by the certificate holder), confirming their quality.

on equipment, fittings with diameters greater than 100 mm, components, fasteners and insulating flanges must be data sheets of manufacturers, the Central procurement workshops (TSZM) or center-harvesting plants (Tse) construction organizations.

on insulating coating made under TSZM or Tse, must be drawn up datasheet (act), which shall include: date of the insulation work, the type of insulation coating and its quality control results.

Paragraph 1 .4 deleted.

1.5. Excavation work and work on the device of the bases in the construction of gas supply should be carried out in accordance with the design and requirements of SNIP 3.02.01-87.

1.6. * finished construction on underground and overground pipelines, gas inlets, and in-house intrashop gas equipment, GRP and the GRU, as well as the installation of LPG reservoir should be building on the passport application forms required 1 * -4.

During the construction of underground gas pipelines stretching over 100 meters and LPG tanks should be prepared taking into account the work logs.

2. assembly and welding of gas pipelines from steel pipes

PREPARATORY WORK

2.1. * to connect the pipes should be used arc (manual, automatic submerged arc welding) and gas welding, butt resistance welding and reflow soldering gas.

types, design elements and dimensions of welded joints of steel pipelines shall comply with GOST 16037-80 and the requirements of this section.Only butt and corner joints should be used for underground gas pipelines.

Structural dimensions of cutting edges when connecting pipes and parts of the same outer diameter with different wall thickness shall comply with the requirements of SNIP III-42-80.

Permissible offset edges of welded pipes must not exceed the value

0,15 S + 0,5 mm,

where S - the smallest of the wall thickness of welded pipes, mm.

butt resistance welding and reflow soldering gas pipelines, as well as quality control of these studies should be carried out in accordance with the requirements of VSN 006-89 (Appendix 1) Minneftegazstroy..

2.2 * Each welder to the order of the construction organization should be assigned a number (the stigma), which he is obliged to clear the overlap or at a distance of 50 - 100 mm from the welded joint them on the underground pipeline from the available for inspection.

When welding pipes nominal diameter of 400 mm with two welders each must deliver (afloat or knock) at (stamp) on the borders of their land.

2.3. application of welding materials (electrodes, welding wire and flux) is allowed only if the certificates of manufacturers or their copies.

Before using welding materials, perform visual check on their compliance with the requirements of GOST (TU).Upon detection of defects (dusting a protective coating of the electrodes and their moisture, corrosion, welding wire) use of these materials is not allowed..

2.4 * Before admission welder welding work on gas pipelines need to weld the qualification (test) joints in the following cases:

if a welder for the first time begin to weld the pipeline or have a break from work for welding a calendar month;

if welded pipes made of steel grades, which differ from the previously welded welder according to their properties weldability;

if used for a new brand of welding consumables (electrodes, welding wire, flux);

if changed welding technology..

2.5 * control qualification welds should be carried out: visual inspection for compliance with GOST 16037-80;radiography - GOST 7512-82;mechanical tests - GOST 6996-66 and in accordance with the requirements of this section..

2.6 * At unsatisfactory results of the qualification welds control:

visual inspection - the joint is rejected and further control is not subject;

physical methods or mechanical tests - test should be repeated on twice the number of joints.

In case of a failure on at least one junction when checking the quality of welding consumables should reject the entire batch of material, and when checking the qualifications of welders - it must pass additional practice on welding, and then cook the new qualification welds to be tested in accordance withthe above requirements.

WORKS

2.7. Before assembly, welding steel pipes must be:

clear them from the internal cavity of any obstructions (soil, ice, snow, water, construction debris, and other individual items.);

check the geometric dimensions of cutting edges, smooth straighten dents on the ends of the tubes to a depth of 3.5% of the outer diameter of the pipe;

clean to bare metal edges and adjacent inner and outer surfaces of pipes to a minimum width of 10 mm.

ends of pipes with cracks, tears, nicks, teaser chamfer depth of more than 5 mm, it should be cut.

At temperatures below -5 ° C edit all pipes without heating is not allowed.

2.8. * assembly of pipes for welding should be performed on the inventory pads using centralizers and other devices.

to secure the tubes in a fixed position for welding electrodes applied to the welding seam root joint, should be carried out uniformly located on the junction pot holders in the amount of perimeter pcs .:

for pipe diameters up to 80 mm inclusive.- 2

«« «St.80 "up to 150 mm inclusive.- 3

"" "150" "300" "- 4

" "" 300 "every 250 mm Height

tack should be 1/3 of the pipe wall thickness, but not less than 2 mm;the length of each pot holders - with a diameter of 20-30 mm abutting pipes up to 50 mm inclusive .;50-60 mm - in diameter abutting pipes up to 50 mm..

2.9 * manual arc welding and orbital rotary joints of pipes with a wall thickness of 6 mm should be done in at least two layers, and with a wall thickness of 6 mm - at least three layers.Each layer before applying the subsequent seam must be carefully cleared of slag and spatter.

Gas welding gas acetylene is allowed for a nominal diameter of 150 mm, with wall thicknesses up to 5 mm inclusive.chamfered edges, with a wall thickness of 3 mm inclusive.without bevel edges.Gas welding must be carried out in a single layer.

Gas welding using a propane-butane mixture is permitted only for gas pressures up to 0,005 MPa (0.05 kgf / cm2) incl.nominal diameter of 150 mm with a wall thickness up to 5 mm inclusive.

joints of gas pipelines with a diameter of 920 mm and more, without the remaining welded rings, must be made with jelly root inside the pipe.

2.10. submerged arc welding should be performed on the first sing welded by manual arc welding (with the same electrodes that grab the joints), or semi-automatic (automatic) welding of carbon dioxide in the environment.

2.11. * length welded into the linear part of the underground pipeline installation "reel" should be not less than 200 mm.

2.12. assembly for welding pipes with one-sided longitudinal or spiral weld should be made with offset joints from joints of not less than, mm:

15 for pipes up to 50 mm

50 «« «50 to 100 mm

100«« «St.100 mm

During assembly welding of pipes, in which the factory joints (longitudinal or helical) welded on both sides are allowed produce offset seams provided checks intersection seams physical methods.

2.13. Welding nozzles branches in the transverse locations (ring) of the main gas pipeline welds are not permitted.The distance between the cross-stitch and seam welding of the pipeline to pipe it should be at least 100 mm.

on domestic gas pipelines, as well as in hydraulic fracturing and the GRU with sidebars branches diameter up to 50 mm inclusive.(Including the impulse lines), the distance from the seams are welded fittings to the main pipeline girth welds must be at least 50 mm.

2.14. Welding work outdoors in the rain, snow, fog and wind speed exceeding 10 m / s can only be done while protecting the weld from moisture and wind.

Paragraph 2.15 deleted..

2.16 * necessity of preheating the joints should be determined depending on the grade of steel welded pipes, subdivided into the following groups:

I - pipes calm (cn) and semi-killed (ps) steels: St1, St2, St3,St4 GOST 380-88;08, 10, 15 and 20 in accordance with GOST 1050-88;

II - boiling tubes (CP) steels: St1, St2, St3, St4 GOST 380-88;

III - tube of low alloy steels: 09G2S, 17G1S, 14HGS etc. GOST 19281-89;.10G2 grade according to GOST 4543-71.Preheating

joints should produce when welding pipes with a wall thickness of 5 to 10 mm inclusive.electrodes with rutile or cellulose coated with ambient temperature: below minus 20 ° C - for tubes I and II, below minus 10 ° C - for pipes of group III.The minimum heating temperature should be 100 ° C and measured at a distance of 5-10 mm from the tube edge..

WELDING MATERIALS

2.17 * following types of electrodes should be used for arc welding pipes according to GOST 9467-75, GOST 9466-75:

E42-C, E46-D diameter 3.0;3.25;4.0 mm with cellulosic electrodes - welding the root layer of the pipe I - III groups;

E42A, E42B, E46A, E46B, E50A, E50B diameter of 2.5;3.0;3.25 mm with basic coating - for welding the root layer pipe groups I and III;

E42A, E42B, E46A, E46B, E50A, E50B diameter of 3.25 and 4.0 with a basic coating - welding filler and cover layers of weld pipe groups I and III;

E42-P-R E46 with rutile - welding seam pipes of all layers I and II (DC);

E42-P with rutile - welding seam pipes of all layers I and II (AC).

Paragraph 2.18 deleted..

2.19 * welding wires and fluxes should be selected in accordance with GOST 2246-70 and GOST 9087-81, respectively, depending on the group of welded pipes in the following combinations:

pipe groups I and II - SV-08 and AN-348-A Sv-08A-1 and ASC (TU 108.1424-86) SV-08GA and AN-47;

Pipe Group III - CB-08GA and AN-348-A, ASC-1 (TU 108.1424-86), AN-47.

2.20. When arc welding of pipes in carbon dioxide should be used:

welding wire according to GOST 2246-70 mark CB 08G2S;

carbon dioxide in accordance with GOST 8050-85 not less than 99.5%..

2.21 * When gas welding should be applied: welding wire according to GOST 2246-70 marks SV-08, SV-08A, ST-08GA, CB 08G2S Sv-08GS Sv-12GS;

oxygen technical GOST 5583-78;

acetylene cylinders in accordance with GOST 5457-75 or acetylene obtained in the place of manufacture of works of calcium carbide in accordance with GOST 1460-81.

QUALITY CONTROL

2.22. Operational control in the process of assembly and welding of pipelines should be carried out in accordance with the requirements of SNIP 3.01.01-85 *.

When operational control should check compliance: preparation of pipes, cleaning them, all changes;structural components and welds sizes;the number, size and location of the tack;stacking order of the individual layers of the seam, weld dimensions and shape of the layers..

2.23 * joints, welded or gas arc welding, according to the results of external examination shall comply with Section 2.1 of these rules, as well as meet the following requirements:

seams and surfaces adjacent tubes at a distance of not less than 20 mm (both sides of the joint) should be free of slag, molten metal splashes, scale and other debris;

joints must be free from cracks, burn-through, nezaparennyh craters onto the surface of the pores and undercuts of more than 5% depth of pipe wall thickness (0.5 mm) and a length of more than 1/3 of the perimeter of the interface (150 mm).

2.24. * Of the total number of joints welded joints should be selected to test their physical or mechanical methods of testing.

joints for mechanical tests should be cut in the period of production jobs to avoid tapping (welding of) "coils".Allowed joints for mechanical testing of welded pipe segments in terms of constructed objects..

2.25 * Control physical methods should be subjected to:

certification joints - radiographic method;

selected for monitoring the standards table.* 2 joints of external and internal pipelines - radiographic and ultrasonic methods.

control joints radiography should be done in accordance with GOST 7212-82 *, ultrasound - in accordance with GOST 14782-86.

the ultrasonic method is permitted only subject to a selective backup joint inspection by radiography in the amount of not less than 10% of joints selected for monitoring.If unsatisfactory results of radiographic testing at least one joint of the scope of the control should be increased to 50%.In case of defective joints with all joints welded welder at the facility during the calendar month and checked by an ultrasonic method, should be subjected to radiographic inspection.