About conducting a pneumatic test of the pipeline (general pneumatic test of the pipeline network)

SNiP 3.05.03-85
________________
Registered by Rosstandart as SP 74.13330.2011. -
Database manufacturer's note.

BUILDING REGULATIONS

HEATING NETWORK

Introduction date 1986-07-01

DEVELOPED by the Orgenergostroy Institute of the USSR Ministry of Energy (L. Ya. Mukomel - head of the topic; Candidate of Technical Sciences S. S. Yakobson).

INTRODUCED by the Ministry of Energy of the USSR.

PREPARED FOR APPROVAL by the Main Technical Regulation of the Gosstroy of the USSR (N. A. Shishov).

APPROVED by the Decree of the USSR State Committee for Construction of October 31, 1985 N 178.

With the entry into force of SNiP 3.05.03-85 "Heat Networks", SNiP III-30-74 "Water supply, sewerage and heat supply. External networks and structures" becomes invalid.

AGREED with the USSR Gosgortekhnadzor April 15, 1985

These rules apply to the construction of new, expansion and reconstruction of existing heating networks,

from the source of thermal energy to heat consumers (buildings, structures).

1. GENERAL PROVISIONS

1. GENERAL PROVISIONS

1.1. When building new, expanding and reconstructing existing heating networks, in addition to the requirements of working drawings, work plans (PPR) and these rules, the requirements of SNiP 3.01.01-85, SNiP 3.01.03-84, SNiP III-4-80 and standards .

1.2. Works on the manufacture and installation of pipelines, which are subject to the requirements of the Rules for the Arrangement and Safe Operation of Steam and Hot Water Pipelines of the USSR Gosgortekhnadzor (hereinafter the Rules of the USSR Gosgortekhnadzor), must be carried out in accordance with the indicated Rules and the requirements of these rules and regulations.

1.3. Completed heat networks should be put into operation in accordance with the requirements of SNiP III-3-81.

2. EARTHWORKS

2.1. Earthworks and foundation works must be carried out in accordance with the requirements of SNiP III-8-76, SNiP 3.02.01-83, SN 536-81 and this section.

2.2. The smallest trench bottom width for channelless pipe laying should be equal to the distance between the outer side faces of the insulation of the outermost pipelines of heat networks (associated drainage) with the addition on each side for pipelines with a nominal diameter

the width of the pits in the trench for welding and insulating pipe joints during channelless laying of pipelines should be taken equal to the distance between the outer side faces of the insulation of the outermost pipelines with the addition of 0.6 m on each side, the length of the pits is 1.0 m and the depth from the lower edge of the pipeline insulation - 0.7 m, unless other requirements are justified by the working drawings.

2.3. The smallest width of the bottom of the trench in the case of channel laying of heat networks should be equal to the width of the channel, taking into account the formwork (in monolithic sections), waterproofing, associated drainage and drainage devices, the trench fastening structure with the addition of 0.2 m. In this case, the width of the trench should be at least 1 .0 m

If it is necessary for people to work between the outer edges of the channel structure and the walls or slopes of the trench, the clear width between the outer edges of the channel structure and the walls or slopes of the trench must be at least: 0.70 m - for trenches with vertical walls and 0.30 m - for trenches with slopes.

2.4. Backfilling of trenches during channelless and channel laying of pipelines should be carried out after preliminary tests of pipelines for strength and tightness, complete completion of insulation and construction and installation works.

Backfilling must be carried out in the specified technological sequence:

padding of sinuses between pipelines of channelless laying and the base;

simultaneous uniform backfilling of the sinuses between the walls of the trench and pipelines with channelless laying, as well as between the walls of the trench and channel, chamber with channel laying to a height of at least 0.20 m above pipelines, channels, chambers;

backfilling of the trench to design marks.

Backfilling of trenches (pits) to which additional external loads (except for the own weight of the soil) are not transferred, as well as trenches (pits) at intersections with existing underground utilities, streets, roads, driveways, squares and other structures of settlements and industrial sites should be carried out in accordance with the requirements of SNiP III-8-76.

2.5. After turning off the temporary dewatering devices, the channels and chambers must be visually inspected for the absence of groundwater in them.

3. CONSTRUCTIONS AND INSTALLATION OF BUILDING STRUCTURES

3.1. The construction and installation of building structures should be carried out in accordance with the requirements of this section and the requirements of:

SNiP III-15-76 - during the construction of monolithic concrete and reinforced concrete structures of foundations, supports for pipelines, chambers and other structures, as well as when monolithic joints;

SNiP III-16-80 - when installing prefabricated concrete and reinforced concrete structures;

SNiP III-18-75 - during the installation of metal structures of supports, superstructures for pipelines and other structures;

SNiP III-20-74 - for waterproofing channels (chambers) and other building structures (structures);

SNiP III-23-76 - when protecting building structures from corrosion.

3.2. The outer surfaces of the elements of channels and chambers supplied to the route must be coated with a coating or glued waterproofing in accordance with the working drawings.

The installation of channel elements (chambers) in the design position should be carried out in the technological sequence linked to the project for the production of work on installation and preliminary testing of pipelines for strength and tightness.

Support pads for sliding supports of pipelines must be installed at the distances provided for in SNiP II-D. 10-73* (II-36-73*).

3.3. Monolithic fixed shield supports must be made after the installation of pipelines in the shield support section.

3.4. In places where pipelines of channelless laying enter channels, chambers and buildings (structures), cases of bushings must be put on the pipes during their installation.

At the inlets of underground pipelines into buildings, devices must be made (in accordance with the working drawings) to prevent the penetration of gas into buildings.

3.5. Before installing the upper trays (plates), the channels must be cleared of soil, debris and snow.

3.6. The deviation of the slopes of the bottom of the channel of the heat network and drainage pipelines from the design is allowed by +/- 0.0005, while the actual slope must be at least the minimum allowable according to SNiP II-G.10-73* (II-36-73*) .

The deviation of the installation parameters of other building structures from the design ones must comply with the requirements of SNiP III-15-76, SNiP III-16-80 and SNiP III-18-75.

3.7. The construction organization project and the work execution project should provide for the advanced construction of drainage pumping stations and water outlet devices in accordance with the working drawings.

3.8. Before laying in the trench, drainage pipes must be inspected and cleaned of soil and debris.

3.9. Layer-by-layer filtering of drainage pipelines (except for pipe filters) with gravel and sand must be carried out using inventory separating forms.

3.10. The straightness of the sections of drainage pipelines between adjacent wells should be checked by looking at the light with a mirror before and after backfilling the trench. The pipe circumference reflected in the mirror must have the correct shape. The permissible horizontal deviation from the circumference should be no more than 0.25 of the pipe diameter, but no more than 50 mm in each direction.

Deviation from the correct form of a circle along the vertical is not allowed.

4. PIPING INSTALLATION

4.1. The installation of pipelines must be carried out by specialized installation organizations, while the installation technology must ensure high operational reliability of the pipelines.

4.2. Parts, elements of pipelines (compensators, sumps, insulated pipes, as well as pipeline assemblies and other products) must be manufactured centrally (at the factory, workshops, workshops) in accordance with standards, specifications and project documentation.

4.3. Laying of pipelines in a trench, channel or on above-ground structures should be carried out according to the technology provided for by the project for the production of works and excluding the occurrence of residual deformations in pipelines, violation of the integrity of the anti-corrosion coating and thermal insulation by using appropriate mounting devices, correct placement of simultaneously operating hoisting machines and mechanisms.

The design of fastening mounting devices to pipes must ensure the safety of the coating and insulation of pipelines.

4.4. The laying of pipelines within the shield support must be carried out using pipes of the maximum delivery length. In this case, the welded transverse seams of the pipelines should, as a rule, be located symmetrically with respect to the shield support.

4.5. Laying pipes with a diameter of more than 100 mm with a longitudinal or spiral seam should be carried out with a displacement of these seams by at least 100 mm. When laying pipes with a diameter of less than 100 mm, the offset of the joints must be at least three times the thickness of the pipe wall.

Longitudinal seams must be located within the upper half of the circumference of the pipes to be laid.

Steeply bent and stamped pipe bends may be welded together without a straight section.

Welding of branch pipes and bends into welded joints and bent elements is not allowed.

4.6. When installing pipelines, movable supports and suspensions must be displaced relative to the design position by the distance indicated in the working drawings, in the direction opposite to the movement of the pipeline in working condition.

In the absence of data in the working drawings, the movable supports and hangers of horizontal pipelines must be displaced, taking into account the correction for the outdoor temperature during installation, by the following values:

sliding supports and fastening elements of hangers to the pipe - by half of the thermal elongation of the pipeline at the point of fastening;

rollers of roller bearings - by a quarter of thermal elongation.

4.7. Spring hangers during installation of pipelines must be tightened in accordance with the working drawings.

During hydraulic testing of steam pipelines with a diameter of 400 mm or more, an unloading device should be installed in spring hangers.

4.8. Pipe fittings must be installed in a closed state. Flanged and welded fittings must be made without tension in the pipelines.

The deviation from perpendicularity of the plane of the flange welded to the pipe with respect to the axis of the pipe should not exceed 1% of the outer diameter of the flange, but be no more than 2 mm at the top of the flange.

4.9. Bellows (wavy) and stuffing box expansion joints should be mounted assembled.

When laying underground heating networks, the installation of expansion joints in the design position is allowed only after preliminary tests of pipelines for strength and tightness, backfilling of channelless pipelines, channels, chambers and shield supports.

4.10. Axial bellows and stuffing box compensators should be installed on pipelines without breaking the compensator axes and pipeline axes.

Permissible deviations from the design position of the connecting pipes of expansion joints during their installation and welding should not exceed those specified in the technical specifications for the manufacture and supply of expansion joints.

4.11. When mounting bellows compensators, their twisting relative to the longitudinal axis and sagging under the action of their own weight and the weight of adjacent pipelines are not allowed. Slinging expansion joints should be done only by the branch pipes.

4.12. The installation length of bellows and stuffing box expansion joints must be taken from the working drawings, taking into account the correction for the outside air temperature during installation.

Stretching expansion joints to the installation length should be carried out using the devices provided for by the design of the expansion joints, or tension mounting devices.

4.13. Stretching of the U-shaped compensator should be performed after the completion of the installation of the pipeline, quality control of welded joints (except for the closing joints used for tension) and fixing the structures of fixed supports.

The expansion joint must be stretched to the value specified in the working drawings, taking into account the correction for the outside air temperature when welding the closing joints.

The expansion joint must be stretched simultaneously from both sides at the joints located at a distance of at least 20 and not more than 40 pipeline diameters from the axis of symmetry of the expansion joint, using clamping devices, unless other requirements are justified by the project.

On the section of the pipeline between the joints used for stretching the expansion joint, it is not necessary to carry out preliminary displacement of supports and hangers in comparison with the project (working draft).

4.14. Immediately before assembling and welding pipes, it is necessary to visually inspect each section for the absence of foreign objects and debris in the pipeline.

4.15. The deviation of the slope of pipelines from the design is allowed by +/- 0.0005. In this case, the actual slope must be at least the minimum allowable according to SNiP II-G.10-73 * (II-36-73 *) .

The movable supports of the pipelines must be adjacent to the supporting surfaces of the structures without gap and distortion.

4.16. When performing installation work, the following types of hidden work are subject to acceptance with the preparation of survey reports in the form given in SNiP 3.01.01-85: preparation of the surface of pipes and welded joints for anti-corrosion coating; implementation of anticorrosive coating of pipes and welded joints.

An act should be drawn up on the stretching of compensators in the form given in the mandatory Appendix 1.

4.17. Protection of heat networks from electrochemical corrosion must be carried out in accordance with the Instructions for the protection of heat networks from electrochemical corrosion, approved by the USSR Ministry of Energy and the RSFSR Ministry of Housing and Communal Services and agreed with the USSR State Construction Committee.

5. ASSEMBLY, WELDING AND QUALITY CONTROL OF WELD JOINTS

5.1. Welders are allowed to tack and weld pipelines if they have documents for the right to manufacture welding work in accordance with the Rules for the certification of welders, approved by the USSR Gosgortekhnadzor.

5.2. Before being allowed to work on welding joints of pipelines, the welder must weld a tolerance joint under production conditions in the following cases:

with a break in work for more than 6 months;

when welding pipelines with a change in the group of steel, welding consumables, technology or welding equipment.

On pipes with a diameter of 529 mm or more, it is allowed to weld half the perimeter of the tolerance joint; at the same time, if the tolerance joint is a vertical fixed joint, the ceiling and vertical sections of the seam should be welded.

The tolerance joint must be of the same type with the production one (the definition of the same type of joint is given in the Rules for the certification of welders of the USSR Gosgortekhnadzor).

The tolerance joint is subject to the same types of control that are subject to production welded joints in accordance with the requirements of this section.

Manufacturing jobs

5.3. The welder is obliged to knock out or build up a brand at a distance of 30-50 mm from the joint from the side accessible for inspection.

5.4. Before assembling and welding, it is necessary to remove the end caps, clean the edges and the inner and outer surfaces of the pipes adjacent to them to a width of at least 10 mm.

5.5. Welding methods, as well as types, structural elements and dimensions of welded joints of steel pipelines must comply with GOST 16037-80.

5.6. Joints of pipelines with a diameter of 920 mm or more, welded without the remaining backing ring, must be made with welding of the weld root inside the pipe. When welding inside the pipeline, the responsible contractor must be issued a work permit for the performance of high-risk work. The procedure for issuing and the form of the work permit must comply with the requirements of SNiP III-4-80.

5.7. When assembling and welding pipe joints without a backing ring, the offset of the edges inside the pipe should not exceed:

for pipelines that are subject to the requirements of the USSR Gosgortekhnadzor Rules, in accordance with these requirements;

for other pipelines - 20% of the pipe wall thickness, but not more than 3 mm.

At the joints of pipes assembled and welded on the remaining backing ring, the gap between the ring and the inner surface of the pipe should not exceed 1 mm.

5.8. Assembly of pipe joints for welding should be carried out using mounting centering devices.

Editing smooth dents at the ends of pipes for pipelines that are not subject to the requirements of the USSR Gosgortekhnadzor Rules is allowed if their depth does not exceed 3.5% of the pipe diameter. Sections of pipes with deeper dents or tears should be cut out. The ends of pipes with nicks or chamfers with a depth of 5 to 10 mm should be cut off or corrected by surfacing.

5.9. When assembling a joint using tacks, their number should be for pipes with a diameter of up to 100 mm - 1 - 2, with a diameter of more than 100 to 426 mm - 3 - 4. For pipes with a diameter of more than 426 mm, tacks should be placed every 300-400 mm around the circumference.

Tacks should be evenly spaced around the perimeter of the joint. The length of one tack for pipes with a diameter of up to 100 mm - 10 - 20 mm, a diameter of more than 100 to 426 mm - 20 - 40, a diameter of more than 426 mm - 30 - 40 mm. The height of the tack should be with a wall thickness S up to 10 mm - (0.6 - 0.7) S, but not less than 3 mm, with a larger wall thickness - 5 - 8 mm.

The electrodes or welding wire used for tacks must be of the same grade as for welding the main seam.

5.10. Welding of pipelines, which are not subject to the requirements of the Rules of the USSR Gosgortekhnadzor, is allowed to be carried out without heating the welded joints:

at an outdoor temperature of up to minus 20 degrees C - when using carbon steel pipes with a carbon content of not more than 0.24% (regardless of the pipe wall thickness), as well as low-alloy steel pipes with a wall thickness of not more than 10 mm;

at an outdoor temperature of up to minus 10 degrees C - when using pipes made of carbon steel with a carbon content of more than 0.24%, as well as pipes made of low-alloy steel with a wall thickness of more than 10 mm.

At a lower outdoor temperature, welding should be carried out in special booths, in which the air temperature in the area of ​​the welded joints must be maintained not lower than the specified one.

It is allowed to carry out welding work on outdoors when heating the welded ends of pipes over a length of at least 200 mm from the joint to a temperature of at least 200 degrees C. After welding is completed, a gradual decrease in the temperature of the joint and the adjacent pipe zone should be ensured by covering them with an asbestos sheet or using another method.

Welding (at negative temperature) of pipelines that are subject to the requirements of the USSR Gosgortekhnadzor Rules must be carried out in compliance with the requirements of these Rules.

In case of rain, wind and snowfall, welding work may only be carried out if the welder and the welding site are protected.

5.11. Welding of galvanized pipes should be carried out in accordance with SNiP 3.05.01-85.

5.12. Before welding pipelines, each batch of welding consumables (electrodes, welding wire, fluxes, shielding gases) and pipes must be subjected to incoming inspection:

for the presence of a certificate with verification of the completeness of the data given in it and their compliance with the requirements of state standards or technical specifications;

for the presence on each box or other packaging of an appropriate label or tag with verification of the data given on it;

for the absence of damage (damage) to the packaging or the materials themselves. If damage is found, the question of the possibility of using these welding consumables must be decided by the organization performing the welding;

on the technological properties of the electrodes in accordance with GOST 9466-75 or departmental normative documents approved in accordance with SNiP 1.01.02-83.

5.13. When applying the main seam, it is necessary to completely cover and digest the potholders.

Quality control

5.14. Quality control of welding works and welded joints of pipelines should be carried out by:

checking the serviceability of welding equipment and measuring instruments, the quality of the materials used;

operational control during assembly and welding of pipelines;

external inspection of welded joints and measurements of weld dimensions;

checking the continuity of joints by non-destructive control methods - radiographic (X-ray or gamma rays) or ultrasonic flaw detection in accordance with the requirements of the Rules of the USSR Gosgortekhnadzor, GOST 7512-82, GOST 14782-76 and other standards approved in the prescribed manner. For pipelines that are not subject to the Rules of the USSR Gosgortekhnadzor, it is allowed to use magnetographic control instead of radiographic or ultrasonic testing;

mechanical tests and metallographic studies of control welded joints of pipelines, which are subject to the requirements of the USSR Gosgortekhnadzor Rules, in accordance with these Rules;

strength and tightness tests.

5.15. During the operational quality control of welded joints of steel pipelines, it is necessary to check the compliance with the standards of structural elements and dimensions of welded joints (blunting and cleaning of edges, the size of the gaps between the edges, the width and reinforcement of the weld), as well as the technology and mode of welding, the quality of welding materials, tacks and weld seam.

5.16. All welded joints are subject to external inspection and measurement.

Joints of pipelines welded without backing ring with welding of the root of the seam are subjected to external inspection and measurement of the dimensions of the seam outside and inside the pipe, in other cases - only outside. Before inspection, the weld and adjacent pipe surfaces must be cleaned of slag, splashes of molten metal, scale and other contaminants to a width of at least 20 mm (on both sides of the weld).

The results of an external examination and measurement of the dimensions of welded joints are considered satisfactory if:

there are no cracks of any size and direction in the seam and the adjacent area, as well as undercuts, sagging, burns, unwelded craters and fistulas;

the dimensions and number of volumetric inclusions and recessions between the rollers do not exceed the values ​​given in Table. one;

the dimensions of lack of penetration, concavity and excess penetration at the root of the weld of butt joints made without the remaining backing ring (if it is possible to inspect the joint from inside the pipe) do not exceed the values ​​given in Table. 2.

Joints that do not meet the listed requirements are subject to correction or removal.

Table 1

table 2

5.17. Welded joints are subjected to continuity testing by non-destructive testing methods:

pipelines that are subject to the requirements of the USSR Gosgortekhnadzor Rules, with an outer diameter of up to 465 mm - in the volume provided for by these Rules, with a diameter of more than 465 to 900 mm in a volume of at least 10% (but not less than four joints), with a diameter of more than 900 mm - in the volume not less than 15% (but not less than four joints) total number the same type of joints made by each welder;

pipelines that are not subject to the requirements of the USSR Gosgortekhnadzor Rules, with an outer diameter of up to 465 mm in a volume of at least 3% (but not less than two joints), with a diameter of more than 465 mm - in the amount of 6% (but not less than three joints) of the total number of joints of the same type performed by each welder; in the case of checking the continuity of welded joints using magnetographic testing, 10% of the total number of joints subjected to testing must be checked, in addition, by radiographic method.

5.18. 100% of welded joints of pipelines of heat networks laid in impassable channels under the carriageway, in cases, tunnels or technical corridors together with other engineering communications, as well as at intersections should be subjected to non-destructive control methods:

railways and tram tracks - at a distance of at least 4 m, electrified railways - at least 11 m from the axis of the outermost track;

railways of the general network - at a distance of at least 3 m from the nearest subgrade structure;

motorways - at a distance of at least 2 m from the edge of the carriageway, the reinforced roadside strip or the sole of the embankment;

underground - at a distance of at least 8 m from the structures;

power, control and communication cables - at a distance of at least 2 m;

gas pipelines - at a distance of at least 4 m;

main gas pipelines and oil pipelines - at a distance of at least 9 m;

buildings and structures - at a distance of at least 5 m from walls and foundations.

5.19. Welded seams should be rejected if cracks, non-welded craters, burns, fistulas, as well as lack of penetration at the root of the weld made on the backing ring are found during testing by non-destructive testing methods.

5.20. When checking by radiographic method the welds of pipelines, which are subject to the requirements of the Rules of the USSR Gosgortekhnadzor, pores and inclusions are considered acceptable defects, the dimensions of which do not exceed the values ​​\u200b\u200bspecified in Table. 3.

Table 3

The height (depth) of lack of penetration, concavity and excess penetration at the root of the joint weld, made by one-sided welding without a backing ring, should not exceed the values ​​\u200b\u200bspecified in Table. 2.

Permissible defects in welds according to the results of ultrasonic testing are considered to be defects, measured characteristics, the number of which does not exceed those indicated in Table. four.

Table 4

5.21. For pipelines that are not subject to the requirements of the USSR Gosgortekhnadzor Rules, pores and inclusions whose dimensions do not exceed the maximum allowable in accordance with GOST 23055-78 for welded joints of the 7th class, as well as lack of penetration, concavity and excess penetration at the root of the weld, made by one-sided electric arc welding without a backing ring, the height (depth) of which should not exceed the values ​​\u200b\u200bspecified in Table. 2.

5.22. If non-destructive testing methods reveal unacceptable defects in the welds of pipelines that are subject to the requirements of the Rules of the USSR Gosgortekhnadzor, a repeated quality control of the welds established by these Rules should be carried out, and in the welds of pipelines that are not subject to the requirements of the Rules, - in twice the number of joints according to compared with that specified in clause 5.17.

If unacceptable defects are detected during the re-inspection, all joints made by this welder should be checked.

5.23. Correction by local sampling and subsequent welding (without re-welding the entire joint) is subject to sections of the weld with unacceptable defects, if the dimensions of the sample after removing the defective section do not exceed the values ​​\u200b\u200bspecified in Table. 5.

Welded joints, in the seams of which, in order to correct the defective area, it is required to make a sample with sizes larger than those allowed according to Table. 5 must be completely removed.

Table 5

5.24. Undercuts should be corrected by surfacing thread rollers with a width of not more than 2.0 - 3.0 mm. Cracks must be drilled at the ends, cut down, carefully cleaned and welded in several layers.

5.25. All repaired areas of welded joints should be checked by visual inspection, radiographic or ultrasonic inspection.

5.26. On the executive drawing of the pipeline, drawn up in accordance with SNiP 3.01.03-84, the distances between welded joints, as well as from wells, chambers and subscriber inputs to the nearest welded joints, should be indicated.

6. THERMAL INSULATION OF PIPING

6.1. Installation of heat-insulating structures and protective coatings must be carried out in accordance with the requirements of SNiP III-20-74 and this section.

6.2. Welded and flanged joints should not be insulated to a width of 150 mm on both sides of the joints before testing pipelines for strength and tightness.

6.3. The possibility of performing insulation work on pipelines subject to registration in accordance with the Rules of the USSR Gosgortekhnadzor, before performing tests for strength and tightness, must be agreed with the local authority of the USSR Gosgortekhnadzor.

6.4. When performing filling and backfill insulation during channelless laying of pipelines, it is necessary to provide for temporary devices in the project for the production of works to prevent the pipeline from surfacing, as well as from getting into the soil insulation.

7. TRANSITIONS OF HEAT NETWORKS THROUGH DRIVERS AND ROADS

7.1. The performance of work at the underground (above-ground) crossing of railway and tram tracks, roads, city passages by heating networks should be carried out in accordance with the requirements of these rules, as well as SNiP III-8-76.

7.2. When puncturing, punching, horizontal drilling or other methods of trenchless laying of cases, the assembly and tacking of the sections (pipes) of the case must be performed using a centralizer. The ends of the welded links (pipes) must be perpendicular to their axes. Fractures of the axes of the links (pipes) of the cases are not allowed.

7.3. Reinforced shotcrete-concrete anti-corrosion coating of cases during their trenchless laying should be made in accordance with the requirements of SNiP III-15-76.

7.4. Pipelines within the case should be made of pipes of the maximum delivery length.

7.5. The deviation of the axis of transition cases from the design position for gravity condensate pipelines should not exceed:

vertically - 0.6% of the length of the case, provided that the design slope of the condensate pipelines is ensured;

horizontally - 1% of the length of the case.

The deviation of the transition case axis from the design position for the remaining pipelines should not exceed 1% of the case length.

8. TESTING AND FLUSHING (BLOWING) OF PIPING

8.1. After completion of construction and installation works, pipelines must be subjected to final (acceptance) tests for strength and tightness. In addition, condensate pipelines and pipelines of water heating networks must be washed, steam pipelines - purged with steam, and pipelines of water heating networks with an open heat supply system and hot water supply networks - washed and disinfected.

Pipelines laid without channels and in impassable channels are also subject to preliminary tests for strength and tightness in the course of construction and installation works.

8.2. Preliminary testing of pipelines should be carried out before installing stuffing box (bellows) compensators, sectional valves, closing channels and backfilling pipelines without channel laying and channels.

Preliminary testing of pipelines for strength and tightness should be carried out, as a rule, in a hydraulic way.

At negative temperatures of the outside air and the impossibility of heating water, as well as in the absence of water, it is allowed, in accordance with the project for the production of works, to perform preliminary tests by pneumatic means.

It is not allowed to perform pneumatic tests of above-ground pipelines, as well as pipelines laid in the same channel (section) or in the same trench with existing utilities.

8.3. Pipelines of water heating networks should be tested with a pressure equal to 1.25 working pressure, but not less than 1.6 MPa (16 kgf / sq. cm), steam pipelines, condensate pipelines and hot water supply networks - with a pressure equal to 1.25 working pressure, unless other requirements substantiated by the project (working draft).

8.4. Before performing tests for strength and tightness, it is necessary:

to carry out quality control of welded joints of pipelines and correction of detected defects in accordance with the requirements of Sec. 5;

disconnect the tested pipelines from the existing ones and from the first stop valves installed in the building (structure) with plugs;

install plugs at the ends of the tested pipelines and instead of stuffing box (bellows) compensators, sectional valves during preliminary tests;

provide access throughout the tested pipelines for their external inspection and inspection of welds for the duration of the tests;

fully open fittings and bypass lines.

The use of shut-off valves to disconnect the tested pipelines is not allowed.

Simultaneous preliminary tests of several pipelines for strength and tightness are allowed to be carried out in cases justified by the work design.

8.5. Pressure measurements when testing pipelines for strength and tightness should be carried out using two duly certified (one - control) spring pressure gauges of class at least 1.5 with a body diameter of at least 160 mm and a scale with a nominal pressure of 4/3 of the measured pressure.

8.6. Testing of pipelines for strength and tightness (density), their purging, washing, disinfection must be carried out according to technological schemes (agreed with operating organizations) that regulate the technology and safety of work (including the boundaries of protected zones).

8.7. On the results of testing pipelines for strength and tightness, as well as on their flushing (purging), acts should be drawn up in the forms given in mandatory appendices 2 and 3.

Hydraulic tests

8.8. Piping tests should be carried out in compliance with the following basic requirements:

test pressure must be provided at the top point (mark) of the pipelines;

the water temperature during testing should not be lower than 5 degrees C;

at a negative outdoor temperature, the pipeline must be filled with water at a temperature not exceeding 70 degrees C and it must be possible to fill and empty it within 1 hour;

when gradually filling with water, air must be completely removed from the pipelines;

the test pressure must be maintained for 10 minutes and then reduced to working pressure;

at operating pressure, the pipeline must be inspected along its entire length.

8.9. The results of hydraulic tests for the strength and tightness of the pipeline are considered satisfactory if during their implementation there was no pressure drop, no signs of rupture, leakage or fogging in welds, as well as leaks in the base metal, flange joints, fittings, compensators and other elements of pipelines , there are no signs of shift or deformation of pipelines and fixed supports.

Pneumatic tests

8.10. Pneumatic tests should be performed for steel pipelines with a working pressure of not more than 1.6 MPa (16 kgf / sq. cm) and a temperature of up to 250 degrees C, mounted from pipes and parts tested for strength and tightness (density) by manufacturers in accordance with GOST 3845-75 (at the same time, the factory test pressure for pipes, fittings, equipment and other products and parts of the pipeline must be 20% higher than the test pressure adopted for the installed pipeline).

The installation of cast iron fittings (except for ductile iron valves) is not allowed for the duration of the test.

8.11. Filling the pipeline with air and raising the pressure should be done smoothly at a rate of no more than 0.3 MPa (3 kgf / sq. cm) per hour. Visual inspection of the route [entrance to the security (dangerous) zone, but without descending into the trench] is allowed at pressure equal to 0.3 test, but not more than 0.3 MPa (3 kgf / sq. cm).

For the period of inspection of the route, the pressure increase must be stopped.

When the test pressure is reached, the pipeline must be held to equalize the air temperature along the length of the pipeline. After equalizing the air temperature, the test pressure is maintained for 30 minutes and then gradually decreases to 0.3 MPa (3 kgf / sq. cm), but not higher than the working pressure of the coolant; at this pressure, pipelines are inspected with a mark of defective places.

Leaks are identified by the sound of escaping air, by bubbling when welding joints and other areas are covered with soapy emulsion, and by other methods.

Defects are eliminated only when the excess pressure is reduced to zero and the compressor is turned off.

8.12. The results of preliminary pneumatic tests are considered satisfactory if during their conduct there was no pressure drop on the pressure gauge, no defects were found in welds, flange joints, pipes, equipment and other elements and products of the pipeline, there are no signs of shear or deformation of the pipeline and fixed supports.

8.13. Pipelines of water networks in closed heat supply systems and condensate pipelines should, as a rule, be subjected to hydropneumatic flushing.

Hydraulic flushing is allowed with reuse of flushing water by passing it through temporary sumps installed in the direction of water movement at the ends of the supply and return pipelines.

Flushing, as a rule, should be carried out with process water. Flushing with utility and drinking water is allowed with justification in the project for the production of works.

8.14. Pipelines of water networks of open heat supply systems and hot water supply networks must be flushed hydropneumatically with water drinking quality until complete clarification of the wash water. Upon completion of flushing, the pipelines must be disinfected by filling them with water containing active chlorine at a dose of 75-100 mg / l with a contact time of at least 6 hours. Pipelines with a diameter of up to 200 mm and a length of up to 1 km are allowed, in agreement with the local sanitary authorities. epidemiological service, do not expose to chlorination and limit yourself to washing with water that meets the requirements of GOST 2874-82.

After washing, the results of laboratory analysis of samples of wash water must comply with the requirements of GOST 2874-82. A conclusion is drawn up on the results of washing (disinfection) by the sanitary and epidemiological service.

8.15. The pressure in the pipeline during flushing should not be higher than the working one. The air pressure during hydropneumatic flushing should not exceed the working pressure of the coolant and be no higher than 0.6 MPa (6 kgf / sq. cm).

Water velocities during hydraulic flushing must not be lower than the calculated coolant velocities indicated in the working drawings, and during hydropneumatic flushing, exceed the calculated ones by at least 0.5 m/s.

8.16. Steam pipelines must be purged with steam and vented to the atmosphere through specially installed purge pipes with shutoff valves. To warm up the steam pipeline, all start-up drains must be open before purging. The heating rate should ensure the absence of hydraulic shocks in the pipeline.

The steam velocities during the blowing of each section must be at least the operating velocities for the design parameters of the coolant.

9. ENVIRONMENTAL PROTECTION

9.1. During the construction of new, expansion and reconstruction of existing heating networks, measures to protect environment should be taken in accordance with the requirements of SNiP 3.01.01-85 and this section.

9.2. It is not allowed without agreement with the relevant service: to carry out excavation at a distance of less than 2 m to tree trunks and less than 1 m to shrubs; movement of goods at a distance of less than 0.5 m to crowns or tree trunks; storage of pipes and other materials at a distance of less than 2 m to tree trunks without the installation of temporary enclosing (protective) structures around them.

9.3. Flushing of pipelines in a hydraulic way should be carried out with the reuse of water. Emptying of pipelines after washing and disinfection should be carried out at the places indicated in the project for the production of works and agreed with the relevant services.

9.4. The territory of the construction site after the completion of construction and installation work must be cleared of debris.

Annex 1. ACT ON STRETCHING OF COMPENSATORS

ATTACHMENT 1
Mandatory

____________________________ "_____" _________________ 19_____

Commission consisting of:

(last name, first name, patronymic, position)

_____________________________________________________________,

1. An extension of the compensators listed in the table was presented for inspection and acceptance in the area from the chamber (picket, mine) No. _______ to the chamber (picket, mine) No. _______.

2. The work was carried out according to the design and estimate documentation ____________

_______________________________________________________________

COMMISSION DECISION

The work was carried out in accordance with the design and estimate documentation, state standards, building codes and regulations and meet the requirements for their acceptance.

(signature)

(signature)

Appendix 2. ACT ON TESTING PIPELINES FOR STRENGTH AND TIGHTNESS

APPENDIX 2
Mandatory

_____________________ "_____" ____________ 19____

Commission consisting of:

representative of the construction and installation organization _________________

_____________________________________________________________,
(last name, first name, patronymic, position)

representative of the technical supervision of the customer _____________________

_____________________________________________________________,
(last name, first name, patronymic, position)

representative of the operating organization ______________________

_____________________________________________________________
(last name, first name, patronymic, position)

inspected the work performed by ___________________________

_____________________________________________________________,
(name of construction and installation organization)

and drew up this act as follows:

1. ________________ are presented for examination and acceptance.

_____________________________________________________________
(hydraulic or pneumatic)

pipelines tested for strength and tightness and listed in the table, in the section from chamber (picket, mine) No. ________ to chamber (picket, mine) No. _________ of the route ___________

Length __________ m.
(pipeline name)

2. The work was carried out according to the design and estimate documentation __________________

_____________________________________________________________________
(Name design organization, drawing numbers and date of drawing up)

COMMISSION DECISION

Representative of the construction and installation organization ________________
(signature)

Representative of the technical supervision of the customer _____________________
(signature)

(signature)

Appendix 3. ACT ON FLUSHING (BLOWING) OF PIPELINES

APPENDIX 3
Mandatory

_______________________________________ "____" _______________ 19_____

Commission consisting of:

representative of the construction and installation organization ________________

_____________________________________________________________,
(last name, first name, patronymic, position)

representative of the technical supervision of the customer _____________________

_____________________________________________________________,
(last name, first name, patronymic, position)

representative of the operating organization _____________________

_____________________________________________________________
(last name, first name, patronymic, position)

inspected the work performed by ____________________________

_____________________________________________________________,
(name of construction and installation organization)

and drew up this act as follows:

1. Flushing (purging) of pipelines in the section from chamber (picket, mine) No. __________ to chamber (picket, mine) No. ______ of route _______________________________________________________________________________

_____________________________________________________________________________________
(pipeline name)

length ___________ m.

Flushing (purging) performed ________________________________

_____________________________________________________________.
(medium name, pressure, flow rate)

2. The work was carried out according to the design and estimate documentation _________________

____________________________________________________________________

_____________________________________________________________________.
(name of design organization, drawing numbers and date of drawing up)

COMMISSION DECISION

The works were performed in accordance with the design estimates, standards, building codes and regulations and meet the requirements for their acceptance.

Representative of the construction and installation organization ________________
(signature)

Representative of the technical supervision of the customer _____________________
(signature)

Representative of the operating organization _____________________
(signature)

The text of the document is verified by:
official publication
M.: CITP Gosstroy of the USSR, 1986

P representative of the person carrying out the construction, performing the technical management of the installation work (chief engineer) _____________________________

__________________________________________________________________________

(position, surname, initials,

__________________________________________________________________________

details of the representation document)

P representative of the person preparing project documentation _______

__________________________________________________________________________

(position, surname, initials, details

__________________________________________________________________________

representation document)

P representative of the person carrying out the construction, who performed the pneumatic test of the pipeline (pipeline network), subject to acceptance _____________

__________________________________________________________________________

(position, surname, initials,

__________________________________________________________________________

details of the representation document)

as well as other representatives of persons involved in the acceptance of work on pneumatic testing of the pipeline (pipeline network) _______________________________

(position, surname, initials,

__________________________________________________________________________

details of the representation document)

made an inspection and acceptance of works on pneumatic testing of the pipeline (pipeline network), presented by ________________________________________

(name of the person who actually presented

__________________________________________________________________________

pipeline (pipeline network) for inspection and acceptance)

and have drawn up this act as follows:

1 . A pipeline (pipeline network) of a unit, or a set of equipment, or a cryogenic system, or technical product, or a section of pipelines within the established boundaries (hereinafter referred to as the product), as well as the results of the test ___________

__________________________________________________________________________

(name and designation, serial number of the product,

__________________________________________________________________________

name, designation and purpose of the pipeline

__________________________________________________________________________

(pipeline network), designation according to the scheme, numbers

__________________________________________________________________________

pickets (plugs) at the boundaries, diameter, length and pipe material)

2 . The pipeline (pipeline network) of the product is manufactured (delivered) _____________

__________________________________________________________________________

(name of the manufacturer (supplier,

__________________________________________________________________________

intermediary), name, number and date of issue

__________________________________________________________________________

certificates of state registration, PSRN, TIN,

__________________________________________________________________________

postal details, telephone, fax - for legal entities;

__________________________________________________________________________

surname, name, patronymic, passport data,

__________________________________________________________________________

place of residence, telephone, fax - for individuals)

3 . Accompanying documents for the pipeline (pipeline network) of the product _________________________________________________________________

4 . Project documentation for the pipeline (pipeline network) of the product _________________________________________________________________ has been presented

(room,

__________________________________________________________________________

other details of the drawing, the name of the project documentation, information about persons,

__________________________________________________________________________

preparing a section of project documentation)

5 . Documents were presented confirming the compliance of the pipeline (pipeline network) of the product with the requirements for them, including:

a) for compliance with the requirements of technical and installation documentation of manufacturers and design documentation of developers, technical regulations (norms and rules), other regulatory legal acts _____________________

__________________________________________________________________________

(Name

__________________________________________________________________________

document of conformity, date, number, other details)

b) the results of examinations, examinations, laboratory and other tests and performed works carried out in the process of construction control _____________

__________________________________________________________________________

(document name, date, number, other details)

6 . Held n required tests and trials ___________________________

__________________________________________________________________________

(document name, date, number, other details)

7 . The technological scheme of pneumatic testing of the pipeline (pipeline network) of the product is presented_______________________________________________

8 . A work permit has been presented for work _______________________________

__________________________________________________________________________

(document name, date, number, other details)

9 . Presented a pneumatic test safety procedure___

__________________________________________________________________________

(document name, date, number, other details)

10 . Approved pneumatic test notification submitted ________________________________________________________________

(document name, date, number, other details)

11 . Documents were presented on the elimination of defects and shortcomings of the pipeline (pipeline network) of the product, discovered earlier ____________________________

__________________________________________________________________________

(document name, date, number, other details)

12 . Documents were presented on the verification of power supply systems and other resources and their readiness for pneumatic testing _____

__________________________________________________________________________

(document name, date, number, other details)

13 . Documents were presented based on the results of the survey of objects and works thats have an impact on safety ___________________________________

__________________________________________________________________________

(document name, date, number, other details)

14 . The program and methodology for pneumatic testing of pipelines were presented_

__________________________________________________________________________

(document name, date, number, other details)

15 . A log of pneumatic testing of the pipeline (technological passport) was presented__________________________________________________________________

(document name, date, number, other details)

16 . Pneumatic testing of a pipeline, pipeline section (pipelinenetwork) was carried out at the stage ___________________________________

(indicate the name of the stage of installation work)

17 . Final results of the hydraulic test

17.1 . common data

17.1.1.U values ​​determined for the pneumatic test:

a) test (trial) pressure during strength testing R and \u003d ____ MPa (____ kgf / cm 2);

b) design (working) pressure during the density test R R = _____ MPa (____ kgf / cm 2).

After completion of the installation work, pressure pipelines for water supply and, if necessary, sewerage must be tested for strength and tightness. Based on the results of hydraulic tests, an act is drawn up in the form provided for by SNiP 3.05.04-85 “External networks and water supply and sewerage facilities”. The full name of the act is the act on the acceptance hydraulic test of the pressure pipeline for strength and tightness. It should be noted that an act in the above form is drawn up both during the preliminary and during the acceptance hydraulic test.

Act of hydraulic testing of pipelines we begin to fill in by entering data on the place of the test (name of the settlement), as well as the date of approval of the act. Next, we enter data on the composition of the acceptance committee. The commission should include representatives of the construction and installation organization, the technical supervision of the customer, and the operating organization. You can familiarize yourself with the system of relations between participants in the construction process in more detail. For each member of the commission, we enter the following data into the act: the name of the organization and position, the surname and initials of the representative.

At the next stage of filling out the act, we indicate the name of the object (we find information about the name in the project or building permit), the picket numbers at the boundaries of the test section, the length of the section, the diameter and material of pipes and butt joints.

1. We indicate the working pressure of the pipeline (we take the information from the project) and the test pressure (we take the information from the project, or in case of its absence we calculate according to tables 4 and 5 of SNiP 3.05.04-85 for tightness and strength tests, respectively).

2. We enter into hydraulic test report test gauge data. It is necessary to indicate the accuracy class of the pressure gauge, the upper limit of measurements, the division value of the pressure gauge scale, as well as the height of the pressure gauge relative to the axis of the pipeline. In accordance with SNiP 3.05.04-85, only certified pressure gauges with an accuracy class of at least 1.5 with a scale for a nominal pressure of about 4/3 of the test pressure can be used for hydraulic testing.

3. We calculate the readings of pressure gauges for the values ​​​​of the working and test pressure of the pipeline indicated above in the act. Indications are calculated according to the formulas that are indicated in the act.

4. According to table 6 from SNiP 3.05.04-85 we deduce and enter into act of hydraulic tests sample, which is presented on this page, the allowable flow rate of pumped water, first per 1 kilometer of the pipeline, and then for the length of the test section.

5. We describe the process of hydraulic strength testing, indicating the previously calculated values ​​of test and working pressure, the time during which the test pressure was maintained, the results of inspection of pipelines for ruptures and leaks.

6. We describe the process of hydraulic testing for tightness, indicating the test pressure for tightness, the start and end times of the test, the duration of the test, data on the water level in measuring barrels at the beginning and end of the test, the pressure gauge readings on the decrease in pressure in the pipeline at the end of the test, the volume of water required to restore the pressure to the test pressure, the amount of water flow pumped into the pipeline during the test. The value of ΔР should be taken in accordance with Table 4 of SNiP 3.05.04-85. It should also be noted that the value of the test pressure for tightness Р g should not exceed the value of the acceptance test pressure of the pipeline for strength Р and.

If the pumped water flow rate does not exceed the allowable pumped water flow rate for a test section 1 km or more in length, which are indicated in Table 6 of SNiP 3.05.04-85, then such a pipeline is recognized as having passed the preliminary and acceptance hydraulic tests for tightness.

Based on the results obtained, the commission makes a decision whether the pipeline passed the hydraulic tests or not.

After completion of testing act of hydraulic testing signed by all members of the committee. Changing the form of the act and deviations from it are not allowed.

As you can see, the filling process act of hydraulic tests not complicated, and if you still have questions, then feel free to ask them in the comments, and we will try to answer them promptly. Be sure to subscribe to our resource in in social networks, and be among the first to receive new recommendations on maintaining as-built documentation.

After everything installation work for the arrangement of water communications will be completed, it is necessary to conduct a final test of the entire system in order to put it into operation in the proper form. Tests are carried out in order to identify possible defects in the operation of communication and their subsequent elimination. Stages of work on verification and full information on it are entered in the form of the act approved by SNiP. A sample or example of a document can be seen in our material below.

About how to correctly fill out the form for testing the plumbing system and what such work is, in our article.

Important: tests of the finished internal plumbing in most cases are carried out hydraulically using a large number of water under pressure above the general average. If you have to test the external water supply, then at a temperature of +5 degrees you can still use the hydraulic method, and at more low rates temperature, a pneumatic method is used (pumping the communication with high-pressure air). Both methods in professional circles are called pipe crimping.

Before performing testing (pressure testing) of the finished water pipeline, it is necessary to stock up on a form of the act, in which all important data will be entered. The act is an official document from Appendix 1 of SNiP 3.05.04-85. The name of the document sounds like "Act on the acceptance hydraulic test of the pressure pipeline for strength and tightness."

The very first information that needs to be entered in the document is the city in which the testing work is carried out and the date of the event. Below is a list of committee members who will test the indoor/outdoor plumbing system.

The commission should normally include:

• Representative of the organization that carried out the installation of all communications;
• Representative from the technical supervision service of the customer;
• A person representing the operating organization.

Moreover, it is worth prescribing the organization that the member of the commission represents, and his position in it, and his surname with initials.

You must specify below detailed information about the tested object. That is, enter its full name (you can take it from the design documentation), indicate the numbers of pickets available at the boundaries of the facility, the total length of the water pipeline and its diameter, as well as the material from which the communication is mounted and pipe joints are made.

On this "hat" official document considered to be full.

Conducting system testing

• So, when checking, the water consumption from each plumbing point is taken into account. It should be at least 0.2 liters per second.
• It is worth considering the pressure of the water supply. This is especially important for the highest water intake points. In this case, the pressure should be at least 2-3 meters.
• It is also worth checking the compliance of the parameters of the entire system according to the design documentation. Here they check the length, diameter of the pipeline, as well as the materials from which it is made.
• Visual primary inspection of external and internal communications also avoids strong gusts of the system as a result of testing.
• Pressure testing of the water supply system consists in supplying water under high pressure to the system. The testing time is at least 10 minutes. The pressure when supplying water to the system should be one and a half times higher than the maximum allowable for a particular communication.

Example: household plumbing is able to withstand a maximum gauge pressure of 0.45 MPa or just 45 meters of water column. Therefore, to test such sewerage and water supply, it is necessary to apply a gauge pressure of 0.675 MPa or simply 67.5 meters of water column.

Testing is considered successfully passed if no leaks or ruptures of the water supply (sewage) pipeline are detected under the influence of water.

Further completion of the act

• After the pressure test has been carried out, it is necessary to enter data on the nominal gauge pressure for a specific communication and data on the gauge pressure used in testing in the act of testing the communication for tightness.
• It is also worth indicating the brand of the pressure gauge that was used to test and measure the pressure readings in the system at the time of the test. Here it is also necessary to indicate the height of the measuring device relative to the axis of the pipes.
• Another parameter that must be entered into the act of studying water supply or sewerage for tightness is the time during which the communication strait was made.
• Further in the document indicate to what nominal value the pressure was reduced after the test. Lastly, the members of the commission conduct an inspection of the pipeline and sewerage and enter the results into an act.

Important: it is worth adding to the document all the stages of communication research that were applied in relation to a particular communication (whether the pressure periodically decreased when water was supplied, whether the water pressure was changed, etc.).

• If there were no violations in the tightness of the water supply / sewerage system, then it is recorded in the “Results of the test” column that no leaks or breaks were found at the time of the test.
• Below is the item "Decision of the Commission". In case of successful testing, the commission issues a permit for the commissioning of the water supply system.
• Below, all members of the commission must put their signatures indicating their surnames and initials, as well as their positions.