Crimping of pipes snip. TTK. Hydraulic testing of pressure polyethylene pipelines

After installation, water networks are tested by internal pressure for tightness and strength. A preliminary test of the water supply system should begin only after the joints have acquired the required strength.

Pipelines are tested pneumatically or hydraulically twice. For the first time, water pipes are tested before installing reinforcement and backfilling the trench. This is done to eliminate leaks during chasing or other connections, as well as to detect fistulas in pipes. The pipeline is tested for the second time after backfilling the trench, as well as the completion of all work on the tested section of the pipeline.

When a pressure test is carried out, the pipeline is preliminarily filled with water when pneumatic test- air. The testing of the pipeline should be carried out in separate sections, the length of which does not exceed 1 km.

When testing the water supply system with water, so that there is no displacement of the pipes, the ends of the pipeline must be closed with blind flanges, secured with stops. Then the pipeline from the temporary pipeline is filled with water. At the same time, the air outlet from the pipes is monitored through a valve, which is mounted at the highest point of the pipeline section.

In pipeline with piston pump create the required pressure. During testing of pipelines, it is necessary to take into account the probability of pipe rupture, scattering of fragments, i.e. Every effort must be made to prevent injuries to people.

The pressure to be tested must be:
- for pressure cast iron and steel pipelines- equal to the working pressure, i.e. established by this project, with a coefficient of 1.25. The increase in pressure experienced above the pressure of the worker must be at least 5 kg / cm2, while the pressure of the test person must be at least 10 kg / cm2;
- for asbestos-cement pressure water pipelines– more working pressure by 5kg/cm2;
- for polymer pipelines - equal to the pressure, which is provided for by TU or GOST for this type of pipe, but not less than the working one.

It is believed that the pipeline preliminary test withstood if there were no breaks in fittings and pipes, no violations of the minting of butt joints, no water leaks were found. During the preliminary test of the water supply system, the pressure drop over 10 minutes according to the pressure gauge should not be more than 0.5 kg / cm2 for non-steel pipelines. If the pipeline is steel, then the pressure drop is not allowed.

The pipeline after the hydraulic test is immediately covered with earth and the final test is immediately carried out. The pipeline must be flushed clean water, disconnect the test sections with plugs or flanges from the existing water supply.

The pipeline with socket and socket connections must be filled with water before starting the test and kept in this state for 24 hours. The final test of the plumbing must be carried out without safety valves, hydrants, etc. - instead of them, plugs are installed, while the valves are fully opened (having previously checked the gland packing). It is not allowed to use gate valves to disconnect from the existing networks of the test section.

The water pipeline is considered suitable for putting it into operation if no breaks in fittings, pipes, butt joints are found in it during the hydraulic test, and also if the actual water leaks do not exceed the allowable ones. Often, the final test of the water supply system is combined with its commissioning.

The pipeline must be disinfected before putting it into operation. To do this, it is filled with water for a day, which includes 30-20 mg / l of active chlorine. Then this pipeline is washed. When the bacteriological analysis is satisfactory, the water will be allowed to be used for household and drinking needs.

SNiP 3.05.04-85*

BUILDING REGULATIONS

OUTDOOR NETWORKS AND FACILITIES

WATER SUPPLY AND SEWERAGE

Introduction date 1986-07-01

DEVELOPED BY VODGEO Research Institute of Gosstroy of the USSR (Candidate of Technical Sciences V.I. Gotovtsev - leader of the topic, V.K. Andriadi), with the participation of the Soyuzvodokanalproekt of Gosstroy of the USSR (P.G. Vasiliev and A.S. Ignatovich), Donetsk Promstroyniiproekt of Gosstroy of the USSR (S.A. Svetnitsky), NIIOSP im. N.M. Gersevanova Gosstroy of the USSR (candidate of technical sciences V. G. Galitsky and D. I. Fedorovich), Giprorechtrans of the Ministry of River Fleet of the RSFSR (M. N. Domanevsky), Research Institute of Public Water Supply and Water Purification of the Akkhod Kh. K.D. Pamfilov of the Ministry of Housing and Communal Services of the RSFSR (Doctor of Technical Sciences N.A. Lukinykh, Candidate of Technical Sciences V.P. Krishtul), Institute of Tula Promstroyproekt of the Ministry of Tyazhstroy of the USSR.

INTRODUCED VNII VODGEO Gosstroy USSR.

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

INSTEAD OF SNiP III-30-74 in terms of requirements for the production and acceptance of work on the construction and reconstruction of external networks and water supply and sewerage facilities.

SNiP 3.05.04-85* is a reissue of SNiP 3.05.04-85 with amendment No. 1, approved by Decree of the USSR Gosstroy of May 25, 1990 No. 51.

The change was developed by VNII VODGEO Gosstroy of the USSR and TsNIIEP of engineering equipment of the State Committee for Architecture.

Sections, paragraphs, tables in which changes have been made are marked with an asterisk.

Agreed with the Main Sanitary and Epidemiological Directorate of the Ministry of Health of the USSR by letter dated November 10, 1984 No. 121212/1600-14.

These rules apply to the construction of new, expansion and reconstruction of existing external networks ** and water supply and sewerage facilities settlements and objects of the national economy.

** External networks - in the following text "pipelines".

1. GENERAL PROVISIONS

1.1. When building new, expanding and reconstructing existing pipelines and water supply and sewerage facilities, in addition to the requirements of projects (working projects) ** and these rules, the requirements of SNiP 3.01.01-85*, SNiP 3.01.03-84, SNiP III-4- 80* and other rules and regulations, standards and departmental normative documents approved in accordance with SNiP 1.01.02-83.

** Projects (working projects) - in the following text "projects".

1.2. Completed pipelines and water supply and sewerage facilities should be put into operation in accordance with the requirements of SNiP 3.01.04-87.

2. EARTHWORKS

2.1. Excavation and work on the arrangement of foundations during the construction of pipelines and water supply and sewerage facilities must be carried out in accordance with the requirements of SNiP 3.02.01-87.

3. PIPING INSTALLATION

General provisions

3.1. When moving pipes and assembled sections with anti-corrosion coatings, soft tongs, flexible towels and other means should be used to prevent damage to these coatings.

3.2. When laying pipes intended for domestic and drinking water supply, do not allow surface or Wastewater. Before installation, pipes and fittings, fittings and finished units must be inspected and cleaned from inside and outside from dirt, snow, ice, oils and foreign objects.

3.3. The installation of pipelines should be carried out in accordance with the project for the production of works and technological maps after checking the compliance with the project of the dimensions of the trench, fixing the walls, bottom marks and, in case of above-ground laying, supporting structures. The results of the check should be reflected in the work log.

3.4. Socket pipes without pressure pipes ducts should, as a rule, be laid with a socket up the slope.

3.5. The straightness of sections of free-flow pipelines between adjacent wells, provided for by the project, should be controlled by viewing "into the light" using a mirror before and after backfilling the trench. When viewing a pipeline of circular cross section, the circle visible in the mirror must have the correct shape.

The permissible horizontal deviation from the circle shape should be no more than 1/4 of the pipeline diameter, but not more than 50 mm in each direction. Deviations from correct form vertical circles are not allowed.

3.6. The maximum deviations from the design position of the axes of pressure pipelines should not exceed ± 100 mm in plan, the marks of the trays of non-pressure pipelines - ± 5 mm, and the marks of the top of pressure pipelines - ± 30 mm, unless other standards are justified by the project.

3.7. Laying of pressure pipelines along a gentle curve without the use of fittings is allowed for socket pipes with butt joints on rubber seals with an angle of rotation in each joint of no more than 2 ° for pipes conditional diameter up to 600 mm and not more than 1° for pipes with nominal diameters over 600 mm.

3.8. When installing water supply and sewerage pipelines in mountainous conditions, in addition to the requirements of these rules, the requirements of Sec. 9 SNiP III-42-80.

3.9. When laying pipelines on a straight section of the route, the connected ends of adjacent pipes must be centered so that the width of the socket gap is the same around the entire circumference.

3.10. The ends of pipes, as well as openings in the flanges of shut-off and other fittings, during breaks in laying, should be closed with plugs or wooden plugs.

3.11. Rubber seals for installation of pipelines in conditions low temperatures outdoor air is not allowed to be used in a frozen state.

3.12. To seal (seal) butt joints of pipelines, sealing and "locking" materials, as well as sealants according to the project, should be used.

3.13. Flange connections of fittings and fittings should be mounted in compliance with the following requirements:

flange connections must be installed perpendicular to the axis of the pipe;

the planes of the connected flanges must be even, the nuts of the bolts must be located on one side of the connection; bolts should be tightened evenly crosswise;

elimination of distortions of flanges by installing beveled gaskets or tightening bolts is not allowed;

welding of joints adjacent to the flange connection should be carried out only after uniform tightening of all bolts on the flanges.

3.14. When using soil for the construction of an emphasis supporting wall the pit must be with undisturbed soil structure.

3.15. The gap between the pipeline and the prefabricated part of concrete or brick stops must be tightly filled concrete mix or cement mortar.

3.16. Protection of steel and iron concrete pipes pipelines against corrosion should be carried out in accordance with the design and requirements of SNiP 3.04.03-85 and SNiP 2.03.11-85.

3.17. On the pipelines under construction, the following stages and elements of hidden work are subject to acceptance with the preparation of certificates of examination of hidden works in the form given in SNiP 3.01.01-85 *: preparation of the base for pipelines, arrangement of stops, the size of the gaps and the performance of sealing butt joints, the installation of wells and chambers , anti-corrosion protection of pipelines, sealing of places where pipelines pass through the walls of wells and chambers, backfilling of pipelines with a seal, etc.

Steel pipelines

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

3.19. Before assembling and welding pipes, they should be cleaned of dirt, check the geometric dimensions of the groove, clean the edges and the inner and outer surfaces of the pipes adjacent to them to a width of at least 10 mm to a metallic sheen.

3.20. At the end welding work external insulation of pipes at welded joints must be restored in accordance with the project.

3.21. When assembling pipe joints without a backing ring, the offset of the edges should not exceed 20% of the wall thickness, but not more than 3 mm. For butt joints assembled and welded on the remaining cylindrical ring, the offset of the edges from the inside of the pipe should not exceed 1 mm.

3.22. Assembly of pipes with a diameter of more than 100 mm, made with a longitudinal or spiral weld, should be carried out with a displacement of the seams of adjacent pipes by at least 100 mm. When assembling the joint of pipes, in which the factory longitudinal or spiral seam is welded on both sides, the displacement of these seams can be omitted.

3.23. Transverse welded joints must be located at a distance of at least:

0.2 m from the edge of the pipeline support structure;

0.3 m from the outer and internal surfaces chamber or surface of the building envelope through which the pipeline passes, as well as from the edge of the case.

3.24. The connection of the ends of the joined pipes and sections of pipelines with a gap between them exceeding the permissible value should be carried out by inserting a "coil" with a length of at least 200 mm.

3.25. The distance between the circumferential weld of the pipeline and the seam of the branch pipes welded to the pipeline must be at least 100 mm.

3.26. Assembly of pipes for welding must be carried out using centralizers; it is allowed to straighten smooth dents at the ends of pipes with a depth of up to 3.5% of the pipe diameter and adjust the edges using jacks, roller bearings and other means. Sections of pipes with dents greater than 3.5% of the pipe diameter or with tears should be cut out. The ends of pipes with nicks or chamfers with a depth of more than 5 mm should be cut off.

When applying the root seam, the tacks must be completely digested. The electrodes or welding wire used for tacks must be of the same grade as for welding the main seam.

3.27. Welders are allowed to weld joints of steel pipelines if they have documents for the right to carry out welding work in accordance with the Rules for the certification of welders approved by the USSR Gosgortekhnadzor.

3.28. Before being allowed to work on welding joints of pipelines, each welder must weld a tolerance joint under production conditions (at the construction site) in the following cases:

if he first started welding pipelines or had a break in work for more than 6 months;

if pipes are welded from new steel grades, using new grades of welding consumables (electrodes, welding wire, fluxes) or using new types of welding equipment.

On pipes with a diameter of 529 mm or more, it is allowed to weld half of the tolerance joint.

The tolerance joint is subjected to:

external inspection, in which the weld must meet the requirements of this section and GOST 16037-80;

radiographic control in accordance with the requirements of GOST 7512-82;

mechanical tensile and bending tests in accordance with GOST 6996-66.

In case of unsatisfactory results of checking the tolerance joint, welding and re-inspection of two other tolerance joints are carried out. In the event that unsatisfactory results are obtained during repeated control at least at one of the joints, the welder is recognized as having failed the tests and may be allowed to weld the pipeline only after additional training and repeated tests.

3.29. Each welder must have a brand assigned to him. 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.

3.30. Welding and tacking of butt joints of pipes is allowed to be carried out at an outdoor temperature of up to minus 50 ° C. In this case, welding work without heating the welded joints is allowed to be performed:

at outdoor air temperature up to minus 20°C - when using pipes made of carbon steel 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 outside temperature of up to minus 10°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.

When the outside air temperature is below the above limits, welding work should be carried out with heating in special cabins, in which the air temperature should be maintained not lower than the above, or heating should be carried out on outdoors ends of welded pipes for a length of at least 200 mm to a temperature of at least 200 ° C.

After welding is completed, it is necessary to ensure a gradual decrease in the temperature of the joints and the adjacent zones of the pipes by covering them after welding with an asbestos towel or in another way.

3.31. In multi-layer welding, each layer of the seam must be cleaned of slag and metal spatter before applying the next seam. Weld metal sections with pores, cavities and cracks should be cut down to the base metal, and weld craters welded.

3.32. In manual arc welding, individual layers of the seam must be superimposed so that their closing sections in adjacent layers do not coincide with one another.

3.33. When welding outdoors during precipitation, the welding points must be protected from moisture and wind.

3.34. When quality control of welded joints of steel pipelines should be performed:

operational control during assembly and welding of the pipeline in accordance with the requirements of SNiP 3.01.01-85*;

checking the continuity of welded joints with the identification of internal defects by one of the non-destructive (physical) control methods - radiographic (X-ray or gammagraphic) according to GOST 7512-82 or ultrasonic according to GOST 14782-86.

The use of the ultrasonic method is allowed only in combination with the radiographic method, which must verify at least 10% total number joints to be controlled.

3.35. At operational control the quality of welded joints of steel pipelines should be checked for compliance with the standards of structural elements and dimensions of welded joints, welding method, quality of welding materials, edge preparation, gap size, number of tacks, as well as serviceability of welding equipment.

3.36. All welded joints are subject to external inspection. On pipelines with a diameter of 1020 mm or more, welded joints welded without a backing ring are subject to external inspection and measurement of dimensions outside and inside the pipe, in other cases - only outside. Before inspection, the weld and adjacent surfaces of pipes to a width of at least 20 mm (on both sides of the weld) must be cleaned of slag, splashes of molten metal, scale and other contaminants.

The quality of the weld according to the results of an external examination is considered satisfactory if it is not found:

cracks in the seam and adjacent area;

deviations from the allowable dimensions and shape of the seam;

undercuts, sinkings between the rollers, sagging, burns, unwelded craters and pores emerging on the surface, lack of penetration or sagging at the root of the seam (when examining the joint from inside the pipe);

displacement of the edges of pipes exceeding the allowable dimensions.

Joints that do not meet the listed requirements are subject to correction or removal and re-control of their quality.

3.37. The quality of welds is checked by physical control methods for water supply and sewerage pipelines with a design pressure of: up to 1 MPa (10 kgf / sq. cm) in a volume of at least 2% (but at least one joint for each welder); 1-2 MPa (10-20 kgf / sq. cm) - in a volume of at least 5% (but at least two joints for each welder); over 2 MPa (20 kgf / sq. cm) in a volume of at least 10% (but at least three joints for each welder).

3.38. Welded joints for control by physical methods are selected in the presence of a representative of the customer, who writes down in the work log information about the joints selected for control (location, welder's brand, etc.).

3.39. 100% of welded joints of pipelines laid at crossings under and above railway and tram tracks, through water barriers, under highways, in urban sewers for communications when laid in combination with other engineering communications should be subjected to physical control methods. The length of controlled sections of pipelines at crossing sections should be taken at least as follows:

for railways- the distance between the axes of the extreme tracks and 40 m from them in each direction;

for highways - the width of the embankment along the sole or excavation along the top and 25 m from them in each direction;

for water barriers - within the boundaries of the underwater crossing, determined by Sec. 6 SNiP 2.05.06-85;

For others engineering communications- the width of the crossed structure, including its drainage devices, plus at least 4 m in each direction from the extreme boundaries of the crossed structure.

3.40. Welded seams should be rejected if cracks, unwelded craters, burns, fistulas, as well as lack of penetration at the root of the seam made on the backing ring are found during physical inspection.

When checking welds by radiographic method, the following are considered acceptable defects:

pores and inclusions, the dimensions of which do not exceed the maximum allowable according to GOST 23055-78 for the 7th class of welded joints;

lack of penetration, concavity and excess penetration at the root of the weld, made by electric arc welding without a backing ring, the height (depth) of which does not exceed 10% of the nominal wall thickness, and the total length is 1/3 of the inner perimeter of the joint.

3.41. If unacceptable defects in welds are detected by physical control methods, these defects should be eliminated and the quality control of the doubled number of welds compared to that specified in clause 3.37 should be repeated. If unacceptable defects are detected during the re-inspection, all joints made by this welder should be checked.

3.42. Weld sections with unacceptable defects are subject to correction by local sampling and subsequent welding (as a rule, without overwelding the entire welded joint), if the total length of the samples after removing the defective sections does not exceed the total length specified in GOST 23055-78 for the 7th class.

Correction of defects in the joints should be done by arc welding.

Undercuts should be corrected by surfacing thread rollers with a height of not more than 2 - 3 mm. Cracks less than 50 mm long are drilled at the ends, cut out, carefully cleaned and welded in several layers.

3.43. The results of checking the quality of welded joints of steel pipelines by physical control methods should be documented in an act (protocol).

Cast iron pipelines

3.44. Mounting cast iron pipes, produced in accordance with GOST 9583-75, should be carried out with a seal socket connections hemp resin or bituminized strand and an asbestos-cement lock device, or only a sealant, and pipes produced in accordance with TU 14-3-12 47-83, rubber cuffs supplied complete with pipes without a lock device.

The composition of the asbestos-cement mixture for the lock device, as well as the sealant, is determined by the project.

3.45. The gap between the stop surface of the socket and the end of the pipe to be connected (regardless of the material of the joint seal) should be taken, mm: for pipes with a diameter of up to 300 mm - 5, over 300 mm - 8-10.

3.46. The dimensions of the elements for sealing the butt joint of cast-iron pressure pipes must correspond to the values ​​\u200b\u200bgiven in Table. one.

Table 1

Nominal diameter	Embedding depth, mm
pipes Dy, mm	when using hemp strand	when making a lock	using only sealant

Asbestos-cement pipelines

3.47. The gap between the ends of the pipes to be connected should be taken, mm: for pipes with a diameter of up to 300 mm - 5, over 300 mm - 10.

3.48. Before starting the installation of pipelines, at the ends of the pipes to be connected, depending on the length of the couplings used, marks should be made corresponding to the initial position of the coupling before the installation of the joint and the final position in the mounted joint.

3.49. Connection of asbestos-cement pipes with fittings or metal pipes should be carried out using cast iron fittings or steel welded pipes and rubber seals.

3.50. After completing the installation of each butt joint, it is necessary to check the correct location of the couplings and rubber seals in them, as well as the uniformity of tightening the flange joints of the cast-iron couplings.

Reinforced concrete

and concrete pipelines

3.51. The gap between the stop surface of the socket and the end of the pipe to be connected should be taken, mm:

for reinforced concrete pressure pipes with a diameter of up to 1000 mm - 12-15, with a diameter of over 1000 mm - 18-22;

for reinforced concrete and concrete non-pressure socket pipes with a diameter of up to 700 mm - 8-12, over 700 mm - 15-18;

for seam pipes - no more than 25.

3.52. Butt joints of pipes supplied without rubber rings should be sealed with hemp resin or bituminized strand, or bituminized sisal strand with asbestos-cement mixture as well as polysulfide (thiokol) sealants. The embedment depth is given in Table. 2, while deviations in the depth of embedding of the strand and lock should not exceed ± 5 mm.

The gaps between the stop surface of the sockets and the ends of the pipes in pipelines with a diameter of 1000 mm or more should be sealed from the inside with cement mortar. The brand of cement is determined by the project.

For drainage pipelines, it is allowed to seal the socket working gap to the full depth with cement mortar grade B7.5, unless other requirements are provided for by the project.

table 2

	Embedding depth, mm
Nominal diameter, mm		when making a lock	using only sealants

3.53. Sealing of butt joints of folded non-pressure reinforced concrete and concrete pipes with smooth ends should be carried out in accordance with the project.

3.54. The connection of reinforced concrete and concrete pipes with pipeline fittings and metal pipes should be carried out using steel inserts or reinforced concrete fittings made according to the project.

Pipelines made of ceramic pipes

3.55. The gap between the ends of the laid ceramic pipes (regardless of the material for sealing the joints) should be taken, mm: for pipes with a diameter of up to 300 mm - 5 - 7, for large diameters - 8 - 10.

3.56. Butt joints of pipelines made of ceramic pipes should be sealed with a hemp or sisal bituminized strand, followed by a lock made of B7.5 cement mortar, asphalt (bitumen) mastic and polysulfide (thiokol) sealants, if other materials are not provided for by the project. The use of asphalt mastic is allowed when the temperature of the transported waste liquid is not more than 40 ° C and in the absence of bitumen solvents in it.

The main dimensions of the elements of the butt joint of ceramic pipes must correspond to the values ​​\u200b\u200bgiven in table. 3.

Table 3

	Embedding depth, mm
Nominal diameter, mm	when using hemp or sisal strand	when making a lock	when using only sealants or bituminous mastic

3.57. The sealing of pipes in the walls of wells and chambers must ensure the tightness of the connections and the water tightness of the wells in wet soils.

Pipelines made of plastic pipes*

3.58. Connection of polyethylene pipes high pressure(LDPE) and polyethylene low pressure(HDPE) between themselves and with fittings should be carried out with a heated tool by the method of butt butt welding or socket welding. Welding of polyethylene pipes and fittings various kinds(HDPE and LDPE) is not allowed.

3.59. For welding, installations (devices) should be used that ensure the maintenance of the parameters of technological modes in accordance with OST 6-19-505-79 and other regulatory and technical documentation approved in the prescribed manner.

3.60. Welders are allowed to weld pipelines from LDPE and HDPE if they have documents for the right to perform welding of plastics.

3.61. Welding of pipes made of LDPE and HDPE is allowed to be carried out at an outside air temperature of at least minus 10 ° C. At lower outdoor temperatures, welding should be carried out in insulated rooms.

When performing welding work, the welding site must be protected from the effects of precipitation and dust.

3.62. The connection of polyvinyl chloride (PVC) pipes with each other and with fittings should be carried out by gluing the socket (using GIPC-127 glue in accordance with TU 6-05-251-95-79) and using rubber cuffs supplied complete with pipes .

3.63. Glued joints should not be subjected to mechanical stress for 15 minutes. Pipelines with adhesive joints within 24 hours should not be subjected to hydraulic tests.

3.64. Bonding work should be carried out at an outdoor temperature of 5 to 35°C. The place of work must be protected from the effects of precipitation and dust.

4. PIPELINE CROSSINGS THROUGH NATURAL

AND ARTIFICIAL BARRIERS

4.1. Construction of crossings of pressure pipelines for water supply and sewage through water barriers (rivers, lakes, reservoirs, canals), underwater pipelines of water intakes and sewer outlets within the channel of reservoirs, as well as underpasses through ravines, roads (roads and railways, including metro lines and tram tracks ) and urban passages must be carried out by specialized organizations in accordance with the requirements of SNiP 3.02.01-87, SNiP III-42-80 (section 8) and this section.

4.2. Methods for laying pipeline crossings through natural and artificial barriers are determined by the project.

4.3. The laying of underground pipelines under roads should be carried out under constant mine surveying and geodetic control construction organization for compliance with the planned and high-altitude positions of cases and pipelines provided for by the project.

4.4. Deviations of the axis of protective cases of transitions from the design position for gravity free-flow pipelines should not exceed:

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

horizontally - 1% of the length of the case.

For pressure pipelines, these deviations should not exceed 1 and 1.5% of the case length, respectively.

5. WATER SUPPLY AND SEWERAGE FACILITIES

fence structures surface water

5.1. The construction of structures for the intake of surface water from rivers, lakes, reservoirs and canals should be carried out, as a rule, by specialized construction and installation organizations in accordance with the project.

5.2. Prior to the construction of the foundation for the channel water intakes, their center axes and marks of temporary benchmarks should be checked.

Water wells

5.3. In the process of drilling wells, all types of work and key indicators (driving, diameter of the drilling tool, fastening and extraction of pipes from the well, grouting, water level measurements and other operations) should be reflected in the drilling log. In this case, the name of the passed rocks, color, density (strength), fracturing, granulometric composition of rocks, water content, the presence and size of a “plug” during the sinking of quicksand, the appeared and established water level of all encountered aquifers, absorption of flushing fluid should be noted. Measurement of the water level in wells during drilling should be done before the start of each shift. In flowing wells, water levels should be measured by extending pipes or measuring water pressure.

5.4. In the process of drilling, depending on the actual geological section, it is allowed, within the limits of the aquifer established by the project, by the drilling organization to adjust the depth of the well, diameters and landing depth of technical columns without changing the operating diameter of the well and without increasing the cost of work. Changes to the design of the well should not worsen its sanitary condition and productivity.

5.5. Samples should be taken one by one from each layer of rock, and in a homogeneous layer - after 10 m.

By agreement with the design organization, rock samples may not be taken from all wells.

5.6. Isolation of the exploited aquifer in the well from unused aquifers should be carried out with the drilling method:

rotational - by annulus and annulus grouting of casing strings to the marks provided by the project;

percussion - by crushing and driving the casing string into a layer of natural dense clay to a depth of at least 1 m or by carrying out sub-shoe cementation by creating a cavity with an expander or an eccentric bit.

5.7. To ensure the granulometric composition of the well filter bedding material provided for by the project, clay and fine sand fractions should be removed by washing, and the washed material should be disinfected before backfilling.

5.8. The exposure of the filter during its backfilling should be carried out by raising the casing string each time by 0.5 - 0.6 m after backfilling the well by 0.8 - 1 m in height. The upper boundary of the backfill must be at least 5 m higher than the working part of the filter.

5.9. After completion of drilling and installation of a filter, water wells must be tested by pumping performed continuously during the time provided by the project.

Before starting pumping, the well must be cleaned of cuttings and pumped, as a rule, by an airlift. In fractured rock and gravel-pebble aquifers, pumping should begin with the maximum design drawdown, and in sandy rocks, from the minimum design drawdown. The value of the minimum actual decrease in the water level should be within 0.4 - 0.6 of the maximum actual.

In the event of a forced shutdown of water pumping operations, if the total shutdown time exceeds 10% of the total design time for one lowering of the water level, the pumping of water for this lowering should be repeated. In the case of pumping from wells equipped with a packed filter, the shrinkage of the packing material should be measured during the pumping process once a day.

5.10. The flow rate (productivity) of wells should be determined by measuring capacity with the time of its filling at least 45 s. It is allowed to determine the flow rate using weirs and water meters.

The water level in the well should be measured with an accuracy of 0.1% of the depth of the measured water level.

The flow rate and water levels in the well should be measured at least every 2 hours during the entire pumping time specified by the project.

Control measurements of the depth of the well should be made at the beginning and at the end of pumping in the presence of a representative of the customer.

5.11. During the pumping process, the drilling organization must measure the water temperature and take water samples in accordance with GOST 18963-73 and GOST 4979-49 with their delivery to the laboratory to check the water quality in accordance with GOST 2874-82.

The quality of cementation of all casing strings, as well as the location of the working part of the filter, should be checked by geophysical methods. The mouth of a self-flowing well at the end of drilling must be equipped with a valve and a fitting for a pressure gauge.

5.12. Upon completion of drilling a water well and testing it by pumping water, the top of the production pipe must be welded with a metal cover and have a threaded hole for a plug bolt to measure the water level. The design and drilling numbers of the well, the name of the drilling organization and the year of drilling should be marked on the pipe.

In order to operate the well, in accordance with the project, it must be equipped with instruments for measuring water levels and flow rates.

5.13. Upon completion of drilling and pumping testing of a water well, the drilling organization must transfer it to the customer in accordance with the requirements of SNiP 3.01.04-87, as well as samples of the rocks passed and documentation (passport), including:

geological and lithological section with well design, corrected according to geophysical survey data;

acts for laying a well, installing a filter, cementing casing strings;

a summary log with the results of its interpretation, signed by the organization that performed the geophysical work;

a log of observations of pumping water from a water well;

data on the results of chemical, bacteriological analyzes and organoleptic indicators of water in accordance with GOST 2874-82 and the conclusion of the sanitary and epidemiological service.

Documentation before delivery to the customer must be agreed with the design organization.

Capacitive structures

5.14. When installing concrete and reinforced concrete monolithic and prefabricated capacitive structures, in addition to the requirements of the project, the requirements of SNiP 3.03.01-87 and these rules should also be met.

5.15. Backfilling of soil into the sinuses and backfilling of capacitive structures must be carried out, as a rule, by a mechanized method after laying communications to capacitive structures, conducting a hydraulic test of structures, eliminating identified defects, performing waterproofing of walls and ceilings.

5.16. After the completion of all types of work and the concrete gaining design strength, a hydraulic test of capacitive structures is carried out in accordance with the requirements of Sec. 7.

5.17. Installation of drainage and distribution systems of filtering structures is allowed to be carried out after a hydraulic test of the structure's capacity for tightness.

5.18. Round holes in pipelines for distribution of water and air, as well as for collecting water, should be drilled in accordance with the class indicated in the project.

Deviations from the design width of the slotted holes in polyethylene pipes should not exceed 0.1 mm, and from the design length of the gap in the light ± 3 mm.

5.19. Deviations in the distances between the axes of the couplings of the caps in the distribution and outlet systems of the filters should not exceed ±4 mm, and in the marks of the top of the caps (along the cylindrical protrusions) - ±2 mm from the design position.

5.20. Weir edge marks in water distribution and collection devices (gutters, trays, etc.) must comply with the project and must be aligned with the water level.

When installing overflows with triangular cutouts, the deviations of the marks of the bottom of the cutouts from the design ones should not exceed ±3 mm.

5.21. On the inner and outer surfaces of the gutters and channels for collecting and distributing water, as well as for collecting precipitation, there should be no shells and growths. Trays of gutters and channels must have a slope specified by the project in the direction of water (or sediment) movement. The presence of sites with a reverse slope is not allowed.

5.22. It is allowed to lay the filter load in facilities for water purification by filtration after a hydraulic test of the tanks of these facilities, flushing and cleaning of the pipelines connected to them, individual testing of the operation of each of the distribution and collection systems, measuring and locking devices.

5.23. The materials of the filter load placed in water purification facilities, including biofilters, must comply with the design or the requirements of SNiP 2.04.02-84 and SNiP 2.04.03-85 in terms of particle size distribution.

5.24. The deviation of the layer thickness of each fraction of the filter load from the design value and the thickness of the entire load should not exceed ± 20 mm.

5.25. After completion of work on laying the loading of the filtering facility for drinking water supply, the facility should be washed and disinfected, the procedure for which is presented in the recommended Appendix 5.

5.26. Installation of combustible structural elements of wooden sprinklers, water traps, air guide shields and partitions of fan cooling towers and spray ponds should be carried out after completion of welding work.

6. ADDITIONAL CONSTRUCTION REQUIREMENTS

PIPELINES AND WATER SUPPLY FACILITIES

AND SEWER IN SPECIAL NATURAL

AND CLIMATIC CONDITIONS

6.1. During the construction of pipelines and water supply and sewerage facilities in special natural and climatic conditions, the requirements of the project and this section should be observed.

6.2. Temporary water supply pipelines, as a rule, must be laid on the surface of the earth in compliance with the requirements for laying permanent water supply pipelines.

6.3. The construction of pipelines and structures on permafrost soils should be carried out, as a rule, with negative temperatures outdoor air with the preservation of frozen soil bases. In the case of the construction of pipelines and structures at positive outdoor temperatures, it is necessary to keep the foundation soils in a frozen state and prevent violations of their temperature and humidity regime established by the project.

The preparation of the base for pipelines and structures on ice-saturated soils should be carried out by thawing them to the design depth and compaction, as well as by replacing ice-saturated soils with thawed compacted soils in accordance with the design.

Motion Vehicle and construction machines in the summer, it should be carried out along roads and access roads built in accordance with the project.

6.4. The construction of pipelines and structures in seismic areas should be carried out in the same ways and methods as in normal construction conditions, but with the implementation of the measures provided for by the project to ensure their seismic resistance. Joints of steel pipelines and fittings should be welded only by electric arc methods and the quality of welding should be checked by their physical control methods in the amount of 100%.

During the construction of reinforced concrete capacitive structures, pipelines, wells and chambers, cement mortars with plasticizing additives in accordance with the project.

6.5. All work to ensure the seismic resistance of pipelines and structures performed during the construction process should be reflected in the work log and in the certificates of survey of hidden works.

6.6. When backfilling the sinuses of capacitive structures under construction in undermined territories, the safety of expansion joints should be ensured.

The gaps of the expansion joints over their entire height (from the base of the foundations to the top of the above-foundation part of the structures) must be cleared of soil, construction debris, concrete influx, mortar and formwork waste.

Inspection certificates for concealed works must document all major special works, including: installation of compensators, installation of sliding joints in foundation structures and expansion joints; anchoring and welding in the places of the device of swivel joints of ties-struts; device for passing pipes through the walls of wells, chambers, capacitive structures.

6.7. Pipelines in swamps should be laid in a trench after the water has been drained from it or in a trench flooded with water, provided that the necessary measures are taken in accordance with the project against their floating.

The pipeline strings should be dragged along the trench or moved afloat with plugged ends.

Laying of pipelines on completely backfilled dams with compaction must be carried out as in normal soil conditions.

6.8. When constructing pipelines on subsiding soils, pits for butt joints should be made by compacting the soil.

7. TESTING OF PIPING AND STRUCTURES

Pressure pipelines

7.1. If there is no indication in the project about the method of testing, pressure pipelines are subject to strength and tightness testing, as a rule, by hydraulic method. Depending on the climatic conditions in the construction area and in the absence of water, a pneumatic test method can be used for pipelines with an internal design pressure Рр, not more than:

underground cast iron, asbestos cement and reinforced concrete - 0.5 MPa (5 kgf / sq. cm);

underground steel - 1.6 MPa (16 kgf / sq. cm);

elevated steel - 0.3 MPa (3 kgf / sq. cm).

7.2. Testing of pressure pipelines of all classes should be carried out by a construction and installation organization, as a rule, in two stages:

the first is a preliminary test for strength and tightness, performed after backfilling the sinuses with tamping soil to half the vertical diameter and powdering pipes in accordance with the requirements of SNiP 3.02.01-87 with butt joints left open for inspection; this test can be performed without the participation of representatives of the customer and the operating organization with the drawing up of an act approved by the chief engineer of the construction organization;

the second - the acceptance (final) strength and tightness test should be performed after the pipeline is completely backfilled with the participation of representatives of the customer and the operating organization with the preparation of an act on the test results in the form of mandatory annexes 1 or 3.

Both stages of the test must be carried out before the installation of hydrants, plungers, safety valves, instead of which flange plugs should be installed during the test. Preliminary testing of pipelines available for inspection in working order or subject to immediate backfilling during the construction process (performance of work in winter time, in cramped conditions), with appropriate justification in the projects, it is allowed not to produce.

7.3. Pipelines of underwater crossings are subject to preliminary testing twice: on a slipway or site after welding of pipes, but before applying anti-corrosion insulation to welded joints, and again - after laying the pipeline in a trench in the design position, but before backfilling with soil.

The results of the preliminary and acceptance test must be drawn up by an act in the form of mandatory annex 1.

7.4. Pipelines laid at the crossings through the iron and car roads I and II categories, are subject to preliminary testing after laying the working pipeline in a case (casing) before filling annulus cavity of the case and before filling the working and receiving pits of the transition.

7.5. The values ​​of the internal design pressure Рр and test pressure Ри for carrying out preliminary and acceptance testing of the pressure pipeline for strength must be determined by the project in accordance with the requirements of SNiP 2.04.02-84 and indicated in the working documentation.

The value of the test pressure for tightness Рg for both preliminary and acceptance tests of the pressure pipeline must be equal to the value of the internal design

limit of pressure measurement, accuracy class and scale division of the pressure gauge. In this case, the value of Рg should not exceed the value of the acceptance test pressure of the pipeline for strength Pu.

7.6* Pipelines made of steel, cast iron, reinforced concrete and asbestos-cement pipes, regardless of the test method, should be tested at a length of less than 1 km - at one time; with a greater length - in sections of no more than 1 km. The length of the test sections of these pipelines with the hydraulic test method is allowed to be taken over 1 km, provided that the value of the allowable flow rate of pumped water should be determined as for a section 1 km long.

Pipelines made of LDPE, HDPE and PVC pipes, regardless of the test method, should be tested with a length of no more than 0.5 km at a time, with a longer length - in sections of no more than 0.5 km. With appropriate justification in the project, it is allowed to test these pipelines at one time with a length of up to 1 km, provided that the value of the allowable flow rate of pumped water should be determined as for a section 0.5 km long.

Table 4

for various values ​​of the internal design pressure Рр in the pipeline and characteristics of the technical pressure gauges used

The value of the internal design pressure in the pipeline Рр, MPa (kgf/sq.cm)

upper limit of pressure measurement, MPa (kgf/sq.cm)

division value, MPa (kgf/sq. cm)

upper limit of pressure measurement, MPa (kgf/sq.cm)

division value, MPa (kgf / sq. cm)

upper limit of pressure measurement, MPa (kgf/sq.cm)

division value, MPa (kgf / sq. cm)

MPa (kgf / sq. cm)

Accuracy classes of technical pressure gauges

0.41 to 0.75 (from 4.1 to 7.5)

0.76 to 1.2 (from 7.6 to 12)

1.21 to 2.0 (from 12.1 to 20)

2.01 to 2.5 (from 20.1 to 25)

2.51 to 3.0 (from 25.1 to 30)

3.01 to 4.0 (from 30.1 to 40)

4.01 to 5.0 (from 40.1 to 50)

7.7. If there are no indications in the project on the value of the hydraulic test pressure Pi to perform a preliminary strength test of pressure pipelines, the value is taken in accordance with Table. 5*.

Table 5*

Pipeline characteristics	The value of the test pressure during the preliminary test, MPa (kgf / sq.cm)
1. Steel class I* with butt joints for welding (including underwater) with an internal design pressure Рр up to 0.75 MPa (7.5 kgf / sq. cm)
2. The same, from 0.75 to 2.5 MPa (from 7.5 to 25 kgf / sq. cm)	Internal design pressure with a factor of 2, but not more than the factory test pressure of the pipes
3. The same, St. 2.5 MPa (25 kgf/sq.cm)
4. Steel, consisting of separate sections connected on flanges, with an internal design pressure Рр up to 0.5 MPa (5 kgf / sq. cm)
5. Steel of the 2nd and 3rd classes with butt joints for welding and with an internal design pressure of Pp up to 0.75 MPa (7.5 kgf / sq. cm)
6. The same, from 0.75 to 2.5 MPa (from 7.5 to 25 kgf / sq. cm)	Internal design pressure with a factor of 1.5, but not more than the factory test pressure of the pipes
7. The same. St. 2.5 MPa (25 kgf/sq.cm)	Internal design pressure with a factor of 1.25, but not more than the factory test pressure of the pipes
8. Steel gravity water intake or sewer outlet	Installed by the project
9. Cast iron with butt joints for caulking (according to GOST 9583-75 for pipes of all classes) with an internal design pressure of up to 1 MPa (10 kgf / sq. cm)	Internal design pressure plus 0.5 (5), but not less than 1 (10) and not more than 1.5 (15)
10. The same, with butt joints on rubber cuffs for pipes of all classes	Internal design pressure with a coefficient of 1.5, but not less than 1.5 (15) and not more than 0.6 factory test hydraulic pressure
11. Reinforced concrete	Internal design pressure with a factor of 1.3, but not more than the factory test pressure for watertightness
12. Asbestos cement	Internal design pressure with a coefficient of 1.3, but not more than 0.6 of the factory test pressure for watertightness
13. Plastic	Internal design pressure with a factor of 1.3

* Classes of pipelines are accepted according to SNiP 2.04.02-84.

7.8. Prior to the preliminary and acceptance tests of pressure pipelines, the following must be done:

all work on sealing butt joints, installation of stops, installation of connecting parts and fittings was completed, satisfactory results were obtained for quality control of welding and insulation of steel pipelines;

flange plugs were installed on the outlets instead of hydrants, air vents, safety valves and at the points of connection to the pipelines in operation;

means of filling, pressure testing and emptying the test area were prepared, temporary communications were installed and devices and valves necessary for testing were installed;

drained and ventilated wells for production preparatory work, organized duty at the border of the plots security zone;

the tested section of the pipeline is filled with water (during the hydraulic test method) and air is removed from it.

The procedure for hydraulic testing of pressure pipelines for strength and tightness is set out in the recommended Appendix 2.

7.9. In order to test the pipeline, the responsible work contractor must be issued a work permit for the performance of high-risk work, indicating in it the size of the buffer zone. The form of the work permit and the procedure for issuing it must comply with the requirements of SNiP III-4-80*.

7.10. To measure hydraulic pressure during preliminary and acceptance testing of pipelines for strength and tightness, duly certified spring pressure gauges with an accuracy class of at least 1.5 with a body diameter of at least 160 mm and a scale on nominal pressure about 4/3 test Ri.

To measure the volume of water pumped into and out of the pipeline during the test, measuring tanks or meters should be used. cold water(water meters) in accordance with GOST 6019-83, certified in the prescribed manner.

7.11. The filling of the tested pipeline with water should be carried out, as a rule, with an intensity, cubic m / h, not more than: 4 - 5 - for pipelines with a diameter of up to 400 mm; 6 -10 - for pipelines with a diameter of 400 to 600 mm; 10 - 15 - for pipelines with a diameter of 700 - 1000 mm and 15 - 20 - for pipelines with a diameter of more than 1100 mm.

When filling the pipeline with water, air must be removed through open taps and valves.

7.12. It is allowed to start the acceptance hydraulic test of the pressure pipeline after filling it with soil in accordance with the requirements of SNiP 3.02.01-87 and filling it with water for the purpose of water saturation, and if at the same time it was kept in the filled state for at least: 72 hours - for reinforced concrete pipes (including including 12 hours under internal design pressure Рр); asbestos-cement pipes - 24 hours (including 12 hours under internal design pressure Рр); 24 hours - for cast iron pipes. For steel and polyethylene pipelines exposure for the purpose of water saturation is not performed.

If the pipeline was filled with water before backfilling with soil, then the indicated duration of water saturation is set from the moment the pipeline is backfilled.

7.13. The pressure pipeline is recognized as having passed the preliminary and acceptance hydraulic tests for tightness, if the flow rate of pumped water does not exceed the allowable flow rate of pumped water for a test section 1 km long or more specified in Table. 6*.

If the flow rate of the pumped water exceeds the allowable one, then the pipeline is recognized as having failed the test and measures must be taken to detect and eliminate hidden defects in the pipeline, after which the pipeline must be retested.

TYPICAL TECHNOLOGICAL CHART (TTK)

HYDRAULIC TESTING OF PRESSURE POLYETHYLENE PIPING

I. SCOPE

I. SCOPE

1.1. A typical technological map (hereinafter referred to as TTK) is a comprehensive regulatory document that establishes, according to a specific technology, the organization of work processes for the construction of a structure using the most modern means mechanization, progressive designs and ways of performing work. They are designed for some average working conditions. The TTK is intended for use in the development of Work Performance Projects (PPR), other organizational and technological documentation, as well as for the purpose of familiarizing (training) workers and engineering and technical workers with the rules for performing work on hydraulic testing for strength and density (tightness) of sections of pressure networks .

1.2. This map provides instructions on the organization and technology of work on hydraulic testing for strength and density (tightness) of sections of pressure networks by rational means of mechanization, provides data on quality control and acceptance of work, requirements industrial safety and labor protection in the course of work.

1.3. The regulatory framework for the development of technological maps are:

- working drawings;

- building codes and regulations (SNiP, SN, SP);

- factory instructions and specifications(THAT);

- norms and prices for construction and installation works (GESN-2001 ENiR);

- production norms for the consumption of materials (NPRM);

- local progressive norms and prices, labor costs norms, material and technical resources consumption norms.

1.4. The purpose of creating the TC is to describe solutions for the organization and technology of work on hydraulic testing for strength and density (tightness) of sections of pressure networks in order to ensure their High Quality, as well as:

- cost reduction of works;

- reduction of construction time;

- ensuring the safety of work performed;

- organization of rhythmic work;

- rational use of labor resources and machines;

- unification of technological solutions.

1.5. Work technological maps(RTC) for execution certain types on hydraulic testing for strength and density (tightness) of sections of pressure networks. Working technological maps are developed on the basis of standard maps for the specific conditions of a given construction organization, taking into account its design materials, natural conditions, the existing fleet of machines and building materials tied to local conditions. Working technological maps regulate the means of technological support and the rules for the implementation of technological processes in the production of work. Design features for hydraulic testing for strength and density (tightness) of sections of pressure networks are decided in each specific case by the Working Design. The composition and level of detail of materials developed in the RTK are established by the relevant contracting construction organization, based on the specifics and scope of work performed.

Working flow charts are reviewed and approved as part of the PPR by the head of the General Construction Contractor, in agreement with the Customer's organization, the Customer's Technical Supervision.

1.6. The technological map is intended for the foremen, foremen and foremen who perform hydraulic testing for strength and density (tightness) of sections of pressure sewerage and water supply from 160 mm PE pipes, mounted by welding, as well as employees of the Customer's technical supervision and is designed for specific conditions performance of works in the III-rd temperature zone.

The technological map should be used for the following scopes of work:

Pressure sewer K1n	- 195.0 m;
Plumbing B1	- 170.0 m

II. GENERAL PROVISIONS

2.1. The technological map was developed for a set of works on hydraulic testing for strength and density (tightness) of sections of pressure networks.

2.2. Works on hydraulic testing for strength and density (tightness) of sections of pressure networks are carried out in one shift, the working time during the shift is:

Where 0.06 is the coefficient of decrease in working capacity due to the increase in the duration of the work shift from 8 hours to 10 hours, as well as the time associated with preparing for work and conducting ETO, breaks associated with the organization and technology of the production process and rest for construction machine operators and workers - 10 minutes every hour of work.

2.3. The scope of work consistently performed during hydraulic testing for strength and density (tightness) of sections of pressure networks includes:

- pipeline cleaning (flushing) from soil;

- installation of plugs, pressure gauges, taps, valves;

- device stops;

- connection to the pipeline of test equipment;

- filling the pipeline with water up to the specified pressure;

- Inspection of the pipeline and elimination of detected defects;

- testing and commissioning of the pipeline.

2.5. The technological map provides for the performance of work by an integrated mechanized unit consisting of: combined road machine KDM-130V-03 (tank capacity 6000 l); truck crane KS-55713-1 "Galicianin" (carrying capacity 25.0 t) and vacuum pump HUDING TYP-HC551/07 (working pressure 10.0 MPa) as a driving mechanism.

Fig.1. Combined road machine
ina KDM-130V-03

Fig.2. Vacuum pump HUDING TYP-HC551/07

Fig.3. Cargo characteristics of the automobile jib crane KS-55713-1

2.6. Work on hydraulic testing for strength and density (tightness) of sections of pressure networks should be carried out in accordance with the requirements of the following regulatory documents:

- SP 48.13330.2011. Organization of construction;

- SNiP 3.01.03-84. Geodetic works in construction;

- SNiP 3.05.04-85 *. External networks and water supply and sewerage facilities;

- SNiP 12-03-2001. Labor safety in construction. Part 1. General requirements;

- SNiP 12-04-2002. Labor safety in construction. Part 2. Construction production;

- RD 11-02-2006. Requirements for the composition and procedure for maintaining executive documentation during construction, reconstruction, overhaul capital construction facilities and requirements for certificates of survey of works, structures, sections of engineering and technical support networks;

- RD 11-05-2007. The procedure for maintaining a general and (or) special journal for recording the performance of work during construction, reconstruction, overhaul of capital construction projects.

III. ORGANIZATION AND TECHNOLOGY OF WORK PERFORMANCE

3.1. In accordance with SP 48.13330.2001 "Organization of construction", prior to the commencement of construction and installation works at the facility, the Contractor is obliged to obtain from the Customer in the prescribed manner project documentation and permission to perform construction and installation works. Work without permission is prohibited.

3.2. Prior to the start of work on hydraulic testing for strength and density (tightness) of sections of pressure networks, it is necessary to carry out a set of organizational and technical measures, including:

- appoint persons responsible for the quality and safe performance of construction and installation works, as well as their control and quality of performance;

- briefing the members of the safety team;

- place the necessary machines, mechanisms and inventory in the work area;

- arrange temporary passages and entrances to the place of work;

- provide communication for operational and dispatching control of the production of works;

- establish temporary inventory household premises for storing building materials, tools, inventory, heating workers, eating, drying and storing work clothes, bathrooms, etc.;

- provide workers with tools and personal protective equipment;

- prepare places for storing materials, inventory and other necessary equipment;

- protect construction site and put up warning signs illuminated at night;

- provide the construction site with fire-fighting equipment and signaling equipment;

- draw up an act of readiness of the object for the production of work;

- obtain permits for the performance of work from the technical supervision of the Customer.

3.3. Prior to the start of work on hydraulic testing of sections of pressure networks, the following work must be performed:

- the pipeline is laid in the trench and accepted by the Customer;

- underground utilities crossing the laid pipeline are enclosed in protective boxes and warning signs are installed at the intersection;

- completed all work on closing the ends of the pipeline in the wells with plugs and fixing them with stops;

- flange plugs were installed on the outlets instead of hydrants, safety valves and at the points of connection to production pipelines;

- means for filling and emptying the test area are prepared;

- satisfactory results of quality control of pipeline connections were obtained.

The completion of the preparatory work is recorded in the General Journal of Works (The recommended form is given in RD 11-05-2007).

3.4. After installation, pipeline networks are tested by internal pressure for strength and tightness. Tests are carried out after filling the pipeline with water. Pipelines are hydraulically tested twice.

Preliminary testing of water supply networks should begin after the joints acquire the necessary strength.

3.5. Hydraulic testing of the pipeline is carried out in two stages:

- first - a preliminary test for strength and tightness is performed to eliminate leaks in welded joints and detect fistulas in pipes, after filling the sinuses with soil tamping up to 15 cm on both sides of the pipes with vibrotampers and powdering with soil 20 cm above the top of the pipes with butt joints left open for inspection ;

- second - acceptance (final) testing for strength and tightness is performed after the pipeline is completely backfilled with soil by a mechanized method to the design marks and all work on this section of the pipeline is completed.

3.6. Preliminary tests sewerage pipelines should be made in sections between wells N 6 - N 5; N 5 - N 4; N 4 - N 1, and water pipelines, respectively, between the wells N - N; N-N; N - N 1 selectively at the direction of the customer (one of the three sections). If the results of the selective test are unsatisfactory, then all sections of the pipelines are subject to testing.

3.6.1. The value of the preliminary test (excess) hydraulic pressure for strength, performed before backfilling the trench and installing fittings (hydrants, safety valves, air vents), must be equal to the internal design pressure ( 1.18 MPa ) for polyethylene pressure pipes PE80 SDR13.6 160x9.5 mm with a factor of 1.5, i.e. 1.77 MPa .

3.6.2. Preliminary hydraulic testing of pressure polyethylene pipelines should be carried out in the following order:

- according to the scheme of hydraulic tests (see Fig. 7), connect the section of the pipeline under test 1 through a temporary water supply 5 to the cistern combined road machine KDM-130V-03 , fill it with water with an intensity of not more than 4-5 m / h and withstand without pressure for 2 hours. When filling the pipeline with water, it is necessary to monitor the removal of air from the pipes through an open tap 4 . During testing, so that there is no displacement of the pipes, the ends of the pipeline are closed with blind flanges and fixed with stops 2 ;

- raise the pressure in the pipeline to the test 1.77 MPa , determining it with spring pressure gauges (GOST 8625-77) of an accuracy class of at least 1.5 7 , and by pumping water to maintain it for 10 minutes, not allowing the pressure to drop by more than 0.1 MPa (1 kgf/cm). The pressure drop on the pressure gauge for 10 minutes should be no more than 0.5 kg/cm. Maintaining pressure by pumping water into the pipeline is carried out in order to avoid deformation of the pipeline shell;

- then reduce the test pressure to the internal design pressure 1.18 MPa and, supporting it by pumping water, inspect the pipeline in order to identify defects on it. Exposure of the pipeline under working pressure is carried out for at least 0.5 hours.

3.6.3. The pressure polyethylene pipeline is considered to have passed the preliminary hydraulic test if no ruptures of pipes or joints and fittings are found under the test pressure, and no visible water leaks are found under the working pressure.

3.6.4. Defects identified during testing of the pipeline are eliminated, and the pipeline is retested. In case of minor pipe defects (splits, enamel cracks), a layer of epoxy resin is applied to the defective place, and if cracks and fistulas are found on the pipes and in damaged places, saddles with a rubber gasket are installed.

3.6.5. The completed work is presented to the Customer's technical supervision for inspection and signing of the Pipeline Preliminary Testing Act, in accordance with Appendix 1, SNiP 3.05.04-85 * and obtaining permission to conduct final leak tests (density).

3.7. After the end of the pipeline strength test, they begin to test it for tightness (density). The final hydraulic tests for the density of pressure polyethylene pipelines must be started no earlier than 48 hours after the trench is backfilled and no earlier than 2 hours after the pipeline is filled with water. To do this, the pipelines are washed with clean water, and the test sections are disconnected from the existing water supply with plugs or flanges.

3.8. Testing sections of pipeline networks for tightness (density) is carried out in the following sequence (see Fig. 4):

- vacuum pump HUDING TYP-HC551/07 raise the pressure in the pipeline to the value of the test pressure for tightness equal to the value of the internal design pressure plus 0.5 MPa (5 kgf / cm), taking into account that the value should not exceed the values ​​of the test pressure of the pipeline for strength (in our case, this condition is met MPa );

- fix the start time of the test and measure First level water in a measuring tank 10 ;

- we monitor the pressure drop in the pipeline, while there can be three options for pressure drop.