Registration. The following are not subject to registration with the Rostekhnadzor bodies: - vessels operating at a wall temperature not exceeding 200 °C, in which the pressure does not exceed 0.05 MPa; - devices of air separation plants located inside the heat-insulating casing (regenerators, columns, heat exchangers); - barrels for the transportation of liquefied gases, cylinders with a capacity of up to 100 liters. Registration is carried out on the basis of a written application from the management of the organization-owner of the vessel. To register a vessel, the following must be submitted: - passport of the vessel; - certificate of completion of installation; - diagram of the inclusion of the vessel; - passport safety valve. Rostechnadzor body within 5 days review. provided documentation. If the documentation for the vessel complies with the vessel passport, it puts a stamp on registration, seals the documents. In the case refusal decree. reasons with reference to the relevant documents.
20. Technical examination of pressure vessels
During the technical examination of vessels, it is allowed to use all methods of non-destructive testing. Primary and secondary wire. Inspector of Rostekhnadzor. The wire. ext. And int. Inspections. Also wire. Pneumatic And a hydraulic test - to check the strength of the elements of the vessel and the tightness of the connections. Vessels working with harmful substances Hazard classes 1 and 2 must be thoroughly processed before the start of work inside. Extraordinary examination of vessels is carried out: - if the vessel has not been operated for more than 12 months; - if the vessel was dismantled and installed in a new place; - after repair; - after working out the design service life of the vessel; - after a vessel accident; - at the request of the inspector. The results of the technical examination carried out are recorded in the vessel passport and signed by the members of the commission.
21. Hydraulic and pneumatic testing of pressure vessels
hydraulic test all vessels are subject after their manufacture. Vessels, the manufacture of which is completed at the installation site, transported to the installation site in parts, are subjected to a hydraulic test at the installation site. Vessels that have a protective coating or insulation are subjected to a hydraulic test before coating is applied. Hydraulic testing of vessels, with the exception of cast ones, must be carried out by test pressure. Appl. water with a temperature not lower than 5 °C and not higher than 40 °C. The test pressure shall be controlled by two manometers. After exposure under test pressure, the pressure is reduced to the design pressure, at which the outer surface of the vessel, all its detachable and welded joints are inspected. The vessel is considered to have passed the hydraulic test if: - no leaks, cracks, tears, sweating in the welded joints and on the base metal; - leaks in detachable connections; - visible residual deformations, pressure drop on the pressure gauge. It is allowed to replace the hydraulic test with a pneumatic one, provided that this test is controlled by the acoustic emission method. Pneumatic tests must be carried out according to the instructions with compressed air or inert gas. The holding time of the vessel under test pressure is set by the project developer, but must be at least 5 minutes. Then the pressure in the test vessel should be reduced to the design one and the vessel should be inspected. The test results are recorded in the vessel passport.
Carrying out a hydraulic test. Order of conduct. Test pressure .
A hydraulic test to check the density and strength of pressure equipment, as well as all welded and other joints, is carried out:
a) after installation (additional production) at the installation site of equipment transported to the installation (additional production) site in separate parts, elements or blocks;
b) after reconstruction (modernization), repair of equipment using welding of pressure elements;
c) when carrying out technical examinations and technical diagnostics in cases established by these FNR.
Hydraulic testing of individual parts, elements or blocks of equipment at the place of installation (additional manufacturing) is not mandatory if they have passed a hydraulic test at their places of manufacture or have been subjected to 100% control by ultrasound or other equivalent non-destructive method of flaw detection.
It is allowed to conduct a hydraulic test of individual and prefabricated elements together with the equipment, if under the conditions of installation (additional manufacturing) it is impossible to test them separately from the equipment.
Hydraulic testing of equipment and its elements is carried out after all types of control, as well as after the elimination of detected defects.
The minimum value of the test pressure P pr. During a hydraulic test for steam and hot water boilers, superheaters, economizers, as well as for pipelines within the boiler, is taken:
a) at a working pressure of not more than 0.5 MPa - 1.5 working pressure, but not less than 0.2 MPa;
b) at working pressure over 0.5 MPa - 1.25 working pressure, but not less than working pressure plus 0.3 MPa.
172. The value of test pressure during hydraulic testing of metal vessels (with the exception of cast ones), as well as electric boilers, is determined by the formula:
, (1)
where P is design pressure in case of additional production at the place of operation, in other cases - working pressure, MPa ;
, - allowable stresses for the material of the vessel(electric boiler) or its elements, respectively, at 20 °C and design temperature, MPa.
The ratio of materials of assembly units (elements) of the vessel (electric boiler) operating under pressure is taken according to the used materials of the elements (shells, bottoms, flanges, nozzles, etc.) of the vessel, for which it is the smallest, with the exception of bolts (studs), as well as heat exchange tubes of shell-and-tube heat exchangers.
The test pressure when testing a vessel calculated by zones should be determined taking into account the zone, the design pressure or design temperature of which is less important.
The test pressure for testing a vessel designed to operate in several modes with different design parameters (pressures and temperatures) should be taken equal to the maximum of certain values test pressures for each mode.
The value of test pressure during hydraulic testing of cast and forged vessels is determined by the formula
. (2)
It is allowed to test castings after assembly and welding in an assembled unit or a finished vessel with a test pressure accepted for vessels, subject to 100% control of castings by non-destructive methods.
Water should be used for hydraulic pressure testing of equipment. The water temperature should not be lower than 5 °C and not higher than 40 °C, unless the equipment manufacturer's technical documentation specifies a specific temperature value that is allowed under the conditions for preventing brittle fracture.
The water used for hydraulic testing must not contaminate the equipment or cause severe corrosion.
The temperature difference between the metal and the ambient air during the hydraulic test should not lead to moisture condensation on the surface of the equipment walls.
In technically substantiated cases provided by the manufacturer, it is allowed to use another liquid when conducting a hydraulic test during the operation of vessels.
180. When filling equipment with water, air must be completely removed from it.
The pressure in the equipment under test should be raised smoothly and evenly. The total pressure rise time (up to the test value) must be indicated in the technological documentation. Water pressure during hydraulic testing should be controlled by at least two pressure gauges. Both pressure gauges choose the same type, measurement limit, the same accuracy classes (not lower than 1.5) and divisions.
The use of compressed air or other gas to pressurize equipment filled with water is not permitted.
Holding time under test pressure of steam and hot water boilers, including electric boilers, steam pipelines and hot water, as well as vessels delivered to the installation site as an assembly, is specified by the manufacturer in the instruction manual and must be at least 10 min.
The exposure time under test pressure of vessels of element-by-element block supply, additionally manufactured during installation at the place of operation, must be at least:
a) 30 min. with vessel wall thickness up to 50 mm;
b) 60 min. with a vessel wall thickness over 50 to 100 mm;
c) 120 min. with a vessel wall thickness of more than 100 mm.
LLC "CDKNHO" carries out technical examination (primary, periodic and extraordinary) of equipment and revision of pipelines registered with Rostekhnadzor.
Technical certification of vessels
The scope, methods and frequency of technical examinations of vessels (with the exception of cylinders) must be determined by the manufacturer and specified in the operating manual (instruction). In the absence of such instructions, the frequency of technical examinations within the service life of the vessels must comply with the requirements specified in Appendix No. 4 Federal rules and regulations in the field industrial safety"Industrial safety rules for hazardous production facilities that use equipment that operates under overpressure"(FNP).
Primary, periodic and extraordinary technical examination of vessels subject to registration in the territorial body of Rostekhnadzor is carried out by an authorized specialized organization, as well as a person responsible for exercising production control over the operation of pressure vessels, together with the person responsible for the good condition and safe operation on time, set in the manual (instruction) for operation or in Appendix No. 4FNP .
The primary, periodic and extraordinary technical examination of vessels that are not subject to registration in the territorial body of Rostekhnadzor is carried out by the person responsible for the production control over the operation of pressure vessels, together with the person responsible for the good condition and safe operation within the time limits established in the manual (instructions ) for operation or in Appendix No. 4FNP .
The minimum volume of primary technical examination of vessels includes:
- P conducting visual and measurement control from the internal (if available) and outer surfaces vessel;
- Tocontrol of the wall thickness of the elements of vessels operating under the pressure of corrosive environments, if this is established in the operating manual (instruction) and (or) provided for in the design documentation of the HIF, taking into account the specifics of the technological process in which the vessels are used;
– verification of compliance of installation, piping with technological pipelines, equipment with instrumentation and safety devices of the vessel with the requirements of design and technical documentation;
–
carrying out hydraulic tests.
During the technical examination of vessels, it is allowed to use other methods of non-destructive testing, including the method of acoustic emission.
During the initial technical examination, it is allowed not to conduct an inspection inner surface and hydraulic testing of the vessel supplied assembled, if it is established in the requirements of the operation manual (instruction) and the terms and conditions of preservation specified in it are not violated.
The volume of an extraordinary technical examination is determined by the reasons that caused it to be carried out. When conducting an extraordinary survey, the vessel passport must indicate the reason that necessitated such an examination.
Before inspection (visual and measuring control) of the inner surface of the vessel, other work inside the vessel and its hydraulic test, the vessel must be stopped, cooled (warmed), released from the working medium filling it with ventilation (purging) and neutralization, degassing (if necessary ), disconnected from power sources and all pipelines connecting the vessel with pressure sources or other vessels and process equipment.
The procedure for carrying out these works, depending on the properties of the working medium, the design of the vessel, the features of the scheme of its inclusion and the technological process and the requirements specified in this section of the FNP, must be established in the production instruction or in other documentation for the safe conduct of work (process regulations, instructions) approved by the operating and (or) authorized specialized organization performing the specified work.
The purging of a vessel operating under the pressure of air or inert gases, before the start of work inside its body, is carried out with air, the purging of a vessel operating under the pressure of combustible gases is carried out with inert gas and (or) air. The end of the purge, if necessary, taking into account the properties of the working medium, is determined by the results of the analysis of the medium inside the vessel after the purge.
Vessels working with toxic substances, before the start of work inside, including before visual and measuring control, must be subjected to thorough processing (neutralization, degassing).
Disconnecting the vessel from all pipelines connecting it with pressure sources or other vessels and process equipment is carried out by installing plugs in detachable connections or by directly disconnecting them from the inlet and outlet pipelines at the places of detachable connections with the installation of plugs on the pipeline flanges.
The surfaces of the vessels before the start of the inspection must be cleaned of deposits and dirt for visual and measurement control.
At the request of the person conducting the survey, the lining, insulation and other types of protection must be removed if there are signs indicating the possible presence of defects affecting the safety of the use of the vessel (visually visible mechanical damage; deformation; violations of the integrity of the lining, insulation and protective shell of the hull ; violation of the tightness of the vessel body or its protective shell according to instrument readings). If the design of the vessel and (or) the peculiarity of the technological process does not provide for the possibility of removing insulation and other protective devices case with subsequent restoration, then the diagnosis of the possible presence of defects in places inaccessible for inspection with the removal protective coating or by other methods should be carried out according to the methodology and technology of the project developer and (or) vessel manufacturer, with the involvement, if necessary, of a specialized organization and (or) vessel manufacturer to perform the work.
When conducting an extraordinary technical examination after repair with the use of welding and heat treatment for inspection and testing for strength and density of the vessel, it is allowed to remove outer insulation partly only in a place undergoing renovation.
Hydraulic testing of the vessel must be carried out in accordance with the approved schemes and instructions for the mode of operation and safe maintenance of the vessels, developed by the operating organization, taking into account the requirements of the operating manual (instruction). When conducting a hydraulic test of the vessel, the relevant requirements of subsection "Hydraulic (pneumatic) test" of Section III must be metFNP . The value of the test pressure is determined based on the allowed pressure for the vessel. The exposure time of the vessel under test pressure (if there are no other instructions in the operation manual) must be at least:
- 10 min. - with wall thickness up to 50 mm inclusive;
- 20 minutes. - with wall thickness over 50 to 100 mm inclusive;
- 30 min. - with wall thickness over 100 mm.
Hydraulic tests of vessels should be carried out only with satisfactory results of visual and measuring control of the inner and outer surfaces, provided for by the manual (instruction) for the operation of non-destructive testing and research.
When hydraulic testing vertically installed vessels, the test pressure must be controlled by a pressure gauge installed on top cover(bottom) of the vessel, and in case of constructive impossibility of such installation of the pressure gauge, the value of the test pressure should be determined taking into account the hydrostatic pressure of water, depending on the installation level of the pressure gauge.
In cases where it is impossible to conduct a hydraulic test (large loads from the weight of water on the foundation, interfloor ceilings or on the vessel itself; difficulty in removing water, the presence of a lining inside the vessel), it is allowed to replace it with a pneumatic test in accordance with the requirements of the subsection "Hydraulic (pneumatic) test Section IIIFNP .
Vessels operating under the pressure of media classified as group 1 in accordance with the Technical Regulations of the Customs Union (TR TS 032/2013), before being put into operation after the completion of the technical examination and other work, must be subjected to a leak test by the operating organization with air or inert gas under pressure equal to the working pressure, in accordance with the instructions approved by the operating organization.
Technical certification of pipelines
Pipelines covered byFNP , during the technical examination should be subjected to:
- external inspection and hydraulic testing - before the start-up of the newly installed pipeline, after the reconstruction and repair of the pipeline associated with welding and heat treatment, as well as before the start-up of the pipeline after it has been in a state of conservation for more than two years;
- external inspection - during operation in hot and cold condition with the frequency established in the relevant section FNP .
During the technical examination of pipelines, the use of non-destructive testing methods is also allowed.
Steam bypass pipelines within the turbines and steam extraction pipelines from the turbine to the valve are not subjected to hydraulic testing, provided that their condition is assessed using at least two non-destructive testing methods in the scope established in the operating manual (instruction).
Primary, periodic and extraordinary technical examination of steam and hot water pipelines subject to registration in the territorial bodies of Rostekhnadzor is carried out by an authorized specialized organization. Periodic inspection of pipelines is carried out at least once every three years, unless other periods are established in the operating manual (instruction).
Responsible for the good condition and safe operation of the equipment, together with the person responsible for production control should inspect the pipeline before and after the completion of scheduled repairs, but at least once every 12 months (unless otherwise specified in the operating manual (instruction) on the timing), and also if the nature and extent of repairs do not necessitate an extraordinary survey.
The technical examination of pipelines that are not subject to registration with the bodies of Rostekhnadzor is carried out by a person responsible for the good condition and safe operation of pipelines.
Technical examination (primary, periodic, extraordinary) and revision of technological pipelines are carried out in accordance with the requirements of design and technological documentation, operating manual (instruction).
When conducting a technical examination of pipelines, attention should be paid to sections operating in especially difficult conditions, where the maximum wear of the pipeline is most likely due to corrosion, erosion, vibration and other reasons. These include areas where the direction of flow changes (elbows, tees, tie-ins, drainage devices, as well as sections of pipelines before and after fittings) and where accumulation of moisture, substances that cause corrosion is possible (dead-end and temporarily inoperative sections).
External inspection of pipelines laid open way or in through and semi-through channels, can be carried out without removing the insulation, however, if the person conducting the inspection has doubts about the condition of the walls or welds of the pipeline, the person conducting the inspection has the right to demand partial or complete removal of the insulation.
External inspection of pipelines when laying in impassable channels or when laying without channels is carried out by opening the soil of individual sections and removing insulation at least every two kilometers of the pipeline, unless otherwise provided in the project documentation and the manual (instruction) for the operation of the pipeline.
When conducting a hydraulic test of the pipeline, the relevant requirements of subsection"Hydraulic (pneumatic) test" section III FNP .
To test pipelines located at a height of more than 3 meters, scaffolds or other devices should be provided to enable safe inspection of the pipeline.
The hydraulic test can be replaced by two types of control (radiographic and ultrasonic) in cases of quality control of the connecting welded joint of the pipeline with the pipeline of the operating main, pipelines within the boiler or other process equipment (if there is only one shut-off valve between them), as well as when monitoring more than two one-piece welded joints made during repair.
Pipelines operating under the pressure of media classified as group 1 according to the Technical Regulations of the Customs Union "On the safety of equipment operating under excessive pressure" must be additionally subjected to a leak test by the operating organization with air or inert gas at a pressure equal to the operating pressure, in the order , established by the instruction approved by the operating organization.
GUIDANCE DOCUMENT
VESSELS AND APPARATUS WORKING UNDER PRESSURE
Safety rules and regulations
during hydraulic testing
for strength and tightness
RD 24.200.11-90
GUIDANCE DOCUMENT
Introduction date 01.07.91
This guidance document establishes the rules and safety standards for the preparation and conduct of hydraulic tests for strength and tightness of pressure vessels and apparatus manufactured in accordance with the requirements of OST 26-291, OST 26-01-1183, OST 26-01-900, OST 26-11-06, OST 26-18-6, OST 26-01-9, OST 26-01-221.
Hydraulic testing of products and their elements for strength and tightness by hydrostatic pressure should be carried out on special test hydraulic stands (hereinafter referred to as hydraulic stands) or, in exceptional cases, on assembly stands using portable equipment.
1. GENERAL PROVISIONS
1.2. At each enterprise, in accordance with this guidance document instructions for safe hydraulic testing should be developed and approved by the chief engineer. The main provisions of the instruction, as well as the test scheme, must be posted at the workplace of each hydrotest site.
2. REQUIREMENTS FOR PERSONNEL
2.1. To work on hydraulic stands and workplaces with portable equipment for hydraulic testing, workers of the corresponding specialty are allowed according to the "Unified Tariff and Qualification Reference Book of Works and Professions of Workers (ETKS), certified in in due course with a qualification of at least 4 categories.
The worker must be familiar with the features of this test equipment and be instructed.
The organization of training and instruction in labor safety must comply with the requirements of GOST 12.0.004.
2.3. Recheck knowledge of workers should be carried out at least once a year for workers and once every three years for engineers by a factory qualification commission appointed in the prescribed manner.
2.5. Each hydraulic stand in each shift must be assigned to a separate executor by an order for the workshop. The contractor is obliged to monitor the good condition of the hydraulic stand and keep it in proper order and cleanliness. Each hydraulic stand must have a sign indicating the name of the contractor responsible for this hydraulic stand.
2.6. In preparation for hydraulic testing of each product of a new type, design, etc. the work manager must conduct an unscheduled briefing of workers on the features of this product, point out possible sources of danger and precautions.
2.7. To perform work on slinging and moving cargo, controlling lifting mechanisms from the floor, testers must have an appropriate certificate.
3. REQUIREMENTS FOR THE SITE, EQUIPMENT, RIGGING
3.1. Requirements for the site and workplace when testing with portable equipment
3.1.1. The site for hydraulic testing must comply with the requirements of the current sanitary design standards industrial enterprises CH118, CH119, CH245, building codes and regulations SNiP2, SNiP8, SNiP9.
hydraulic stand (or portable equipment when tested on an assembly stand);
auxiliary equipment and accessories;
of the product under test, taking into account the safe performance of work on its installation and inspection, while the free zone along the perimeter of the maximum possible dimension of the product must be at least 1 m.
3.1.3. The site must have a non-slip floor covering with a slope and (or) holes for water drainage, as well as a protective fence that excludes the possibility of accidental appearance on the site of unauthorized persons and the ingress of working fluid outside the site (Appendix).
There should be a light board on the fence with the inscription “NO ENTRY. TESTING IN PROGRESS" or an appropriate poster.
3.1.4. The site must have general and local working lighting, emergency lighting, as well as portable lamps with a voltage of not more than 42 V. Lighting equipment must comply with the requirements of "".
Lighting should provide illumination on the surface of the product under test:
working - at least 300 lux with fluorescent or 200 lux with incandescent lighting;
emergency - at least 10 from the working one.
3.1.5. The hydraulic testing site must have a circulating water supply system that ensures filling the volume of the tested products or a technical water supply system with a drain system to the sewer.
3.2. Requirements for equipment and accessories
3.2.1. The hydraulic stand must be equipped with:
capacity for working fluid with its circulation system;
a pump for filling and emptying the product;
a pump to create pressure in the product;
receiver (buffer tank) or pneumohydroaccumulator;
pipeline system;
stop valves;
instruments for measuring the pressure and temperature of the working fluid;
safety devices or electrocontact manometers (ECM);
plugs.
The electric motors of the pumps must be enclosed, type IP44.
It is allowed to use the pumping unit with pneumatic drive with a solenoid valve (electric valve) blocking the air supply to the pneumatic actuator. The valve must be controlled by an electric contact pressure gauge (ECM) installed in the line from the pump to the product.
When using phosphors, preservatives or other chemicals as part of the working fluid, the hydraulic stand must be additionally equipped with special containers for preparing neutralizing solutions and neutralizing the working fluid and (or) a device for collecting these substances for their further use.
3.2.2. The location and layout of the equipment must meet the requirements of the current building codes and regulations SNiP9, SNiP10 and ensure the safety and convenience of its operation and repair.
The control panel of a hydraulic stand or portable hydrotesting equipment located in a hazardous area determined by the calculation according to the appendix must be equipped with protection calculated in accordance with the appendix.
3.2.3. When the test product is located underground, a sliding or other mechanical roof should be provided above the buried room, and the site, taking into account the area occupied by the roof in the open position, should have a railing.
3.2.4. The electrical equipment of the hydraulic stand must comply with the requirements of the “Rules for the Arrangement of Electrical Installations”, “Rules for the Technical Operation of Consumer Electrical Installations”, “Safety Rules for the Operation of Consumer Electrical Installations”, as well as building codes and rules Sn iP6.
3.2.5. The hydrostand must be equipped with "STOP" buttons for emergency stop of the pump motor, painted in red. The number of buttons and their location must ensure that the motor can be stopped quickly.
3.2.6. The rotating parts of the feed pump drive must be securely guarded. Contact of working liquid on the drive is not allowed.
3.2.7. The pressure line of the pump must have a receiver to reduce pressure fluctuations in the product under test caused by the pulsating supply of the working fluid. The receiver must be designed for pressure not lower than the maximum allowable for this hydraulic stand.
The receiver must be installed at the hydrotest site in a place that excludes the presence of people and provides accessibility for its inspection, and has a protective fence designed in accordance with the appendix.
It is allowed not to install the receiver and bypass on the hydraulic stands if the pressure in the product under test is reached using a pump without an electric drive (manually).
3.2.8. The location of pipelines should provide free access for inspection and control of their condition.
3.2.9. The pressure measurement should be carried out using two verified pressure gauges, one of which, the control one, should be installed on the product, and the second one - on the control panel of the hydraulic stand.
3.2.10. Manometers for measuring pressure must have the same type, measurement limit, the same division value and an accuracy class of at least:
2.5 at design pressure up to 2.5 MPa (25 kgf / cm 2);
1.5 at a design pressure of more than 2.5 MPa (25 kgf / cm 2) and such a scale on which the measurement limit of the design pressure is in its second third.
3.2.11. The location of the pressure gauges should provide a free view of the pressure gauge scale, while the instrument scale should be in a vertical plane.
The nominal diameter of the case of pressure gauges installed at a height of up to 2 m from the level of the observation site for them must be at least 100 mm, at a height of 2 to 3 m - at least 160 mm. Installation of pressure gauges at a height of more than 3 m from the level of the site is not allowed.
3.2.12. Pressure gauges must be protected from thermal radiation, freezing, mechanical damage.
3.2.13. It is forbidden to use pressure gauges for:
the absence of a seal or brand with a mark on the verification carried out;
overdue verification period;
malfunctions of the pressure gauge (the pointer does not return to the zero mark of the scale when it is turned off, the glass is broken or there are other damages that may affect the correctness of the readings).
Valve adjustment must be carried out in accordance with GOST 12.2.085. The control medium for determining the valve opening moment can be air or water, which must be clean, without mechanical or chemical impurities.
3.2.15. The installation of safety valves must be carried out in accordance with the "Rules for the Design and Safe Operation of Pressure Vessels" and in accordance with circuit diagram hydrostand equipment or a schematic diagram approved by the chief engineer of the enterprise.
It is allowed to use electrocontact pressure gauges (ECM) instead of safety valves, while one pressure gauge is installed on the product and one more - in the line from the pump to the product. The connection of the pump with the pressure gauge EKM must be carried out through a buffer tank or a damping device to protect the pressure gauge from the pulsation of the working fluid in the pipeline.
Pressure gauges must be set to the test pressure and ensure that the pump is turned off when the test pressure is reached.
3.2.16. Rubber, metal-rubber hoses and pipelines used in hydraulic testing must have tags indicating their working and test pressure, test period.
The pressure values on the sleeves and pipelines must not be lower than the pressure value for which this hydraulic stand is designed.
Sleeves must comply with applicable standards or specifications and not have mechanical or chemical damage.
3.2.17. The stop valves of the hydraulic stand must be accessible for maintenance and located no higher than 1.5 m from the floor level. The fittings must be systematically lubricated and scrolled, while the use of any levers is not allowed.
It is not allowed to use fittings that do not have technical documentation (passport, certificate, etc.).
3.2.18. Shut-off valves must be clearly marked:
manufacturer's name or trademark;
conditional pass, mm;
conditional pressure, MPa (kgf / cm 2);
medium flow direction;
material grade.
3.2.19. The marking of the plugs used for hydrotesting should indicate the number of the plug and the pressure value for which it is designed.
3.2.20. The product under test must have:
valve or cock to control the absence of pressure in it before dismantling it. It is allowed to use a three-way valve installed on the product. The outlet of the tap must be directed to a safe place. It is allowed not to install a valve or tap if there are couplings for draining the liquid.
safety valves, the number and throughput of which should exclude the possibility of a pressure exceeding the test pressure in the product. It is allowed to use safety valves with a rupture disc designed for test pressure.
It is allowed not to install safety valves on the product if they are provided in the line between the pump and the tested product and are designed for test pressure.
3.2.21. The working fluid leaving the safety valve must be drained to a safe place. The installation of locking devices on the outlet pipes, as well as between the product and the safety valve is not allowed.
3.2.22. Working fluids used for hydraulic testing must be non-toxic, non-explosive, non-flammable.
It is allowed, at the request of the product developer, to use other liquids with the obligatory observance of the relevant safety measures.
3.2.23. The construction of service platforms and stairs to them (scaffolding) must comply with the current "Safety regulations for construction and installation works" and "General safety regulations and industrial sanitation for enterprises and organizations of mechanical engineering".
3.2.24. Cranes and mechanisms used at the hydraulic testing site must comply with the requirements of the current "Rules for the Construction and Safe Operation of Cranes".
3.2.25. The hydraulic stand and all assembly units, units and devices included in it must have certificates or passports. The use of technological equipment that does not have technical documentation and (or) with mechanical damage threaded, sealing, seating surfaces, traces of stretching, not allowed.
3.2.28. The hydrostand must be registered in the metrological and technical service companies that carry out preventive maintenance.
Scheduled preventive repairs must be carried out in strict accordance with the schedule approved by the chief engineer of the enterprise. After repair, the hydraulic stand must be subjected to a hydraulic pressure test in accordance with clause and certified in accordance with GOST 24555.
3.2.30. Verification of pressure gauges with their sealing or branding should be carried out at least once a year in the prescribed manner.
Additional verification of working pressure gauges with a control one should be carried out at least once every 6 months with the results recorded in a journal. It is allowed to use a certified working pressure gauge for verification of working pressure gauges, which has the same scale and accuracy class with the verified one. Regardless of the indicated terms, the verification of pressure gauges must be carried out if there is any doubt about the correctness of their readings.
3.2.31. Safety valves must be checked at least once a year, at the time established by management enterprises. Checking, repairing and adjusting the safety valve must be documented by an act signed by the workshop mechanic, the repair and adjustment foreman and the locksmith who carried out these works.
The safety valve that has been repaired and adjusted must be sealed together with a tag indicating the test pressure and provided with a number.
Each safety valve must have a technical passport, along with which copies of the passports for the valve and spring from the supplying factories, as well as copies of the certificates of its verification, repair and adjustment, must be kept.
3.2.32. Rubber, metal-rubber hoses and pipelines must be checked and tested at least once a year according to the preventive maintenance schedule. Tests must be carried out in accordance with the relevant regulatory and technical documents for these products and building codes and regulations.
3.2.33. Shut-off valves after each repair must be tested for mechanical strength and tightness with hydraulic pressure that meets the requirements of the regulatory and technical documentation for this valve, but not lower than the maximum pressure for which the hydraulic bench is designed. Trial stop valves must be documented.
Tests should be carried out after fitting and fitter-machining.
4. SAFETY REGULATIONS FOR HYDRAULIC TESTING
4.1. Preparation for hydraulic testing
4.1.1. Products and their elements subject to hydrotesting must be accepted by the QCD service based on the results of external inspection and non-destructive testing.
The value of the test pressure for the product must not exceed the maximum allowable pressure for which the hydraulic stand is designed.
4.1.2. Fasteners and seals used in hydrotesting must be made of materials provided for in the working drawings for the product.
4.1.3. Control and measuring devices, safety devices, fittings, plugs, fasteners, gaskets, etc. must be selected according to the marking for a pressure not lower than the test one.
4.1.4. When installing the product under test on the hydraulic stand on standard or technological supports, its stable position, free access for inspection and the location of drainage holes (“air vents”) at its upper point must be ensured.
Hydrotest scheme, technological process and equipment must ensure complete removal of air when filling the product under test with a working fluid.
4.1.5. Installation of communications, installation of the required fittings, instrumentation must be carried out in full accordance with the approved hydraulic testing scheme.
All free openings of the product under test shall be plugged.
Installation, equipment and inspection of the product at a height of more than 1.5 m should be carried out from special sites (scaffolding).
4.1.6. When mounting flanged connections, the threaded elements must be tightened evenly, alternately tightening diametrically opposite ("crosswise"), while maintaining the parallelism of the flanges.
It is forbidden to use spanners nuts that do not match the size, non-standard and / or with an extension of the handle, as well as a hammer or sledgehammer.
4.1.7. When preparing a working fluid using phosphors, preservatives, as well as when applying indicator coatings to the controlled surfaces of the tested product, a system of general exchange supply and exhaust ventilation must be switched on in the hydrotesting area.
4.2. Carrying out hydraulic tests
4.2.1. A minimum number of people, but not less than two people, should participate in hydraulic testing.
4.2.2. During hydrotesting it is prohibited:
be on the territory of the site to persons not participating in the test;
be from the side of the plugs to the persons participating in the test;
carry out extraneous work on the territory of the hydraulic testing site and work related to the elimination of detected defects on a product under pressure. Repair work may only be carried out after the pressure has been relieved and, if necessary, the operating fluid has been drained.
transport (turn over) a product under pressure;
transport loads over a pressurized product.
4.2.3. The tester is prohibited from:
to carry out tests on a hydraulic stand that is not assigned to him or his team by order in the workshop;
leave without supervision the control panel of the hydraulic stand, the product under test connected to the water supply system (even after the pressure has been removed);
perform under pressure assembly and disassembly of products, equipment, repair of equipment of the hydraulic stand, etc.;
to arbitrarily make changes to the technological process of testing, change the pressure or holding time under pressure, etc.
4.2.4. Hydraulic testing on an assembly stand using portable equipment is allowed in exceptional cases with the written permission of the chief engineer of the enterprise and compliance with the requirements of this guideline.
4.2.5. The product under test must be completely filled with working fluid, the presence in communications and the product air cushions not allowed.
The surface of the product must be dry.
4.2.6. The pressure in the product should rise and fall smoothly. The increase in pressure should be carried out with stops (for the timely detection of possible defects). The value of the intermediate pressure is taken equal to half of the test pressure. The rate of pressure rise should not exceed 0.5 MPa (5 kgf / cm 2) per minute.
The maximum deviation of the test pressure should not exceed ± 5% of its value. The exposure time of the product under test pressure is set by the project developer or indicated in the regulatory and technical documentation for the product.
4.2.7. It is forbidden to be near and (or) inspect the product during the increase in pressure to the test pressure and holding the product under test pressure. The personnel participating in the test must be at the control panel at this time.
Inspection of the product should be carried out after the pressure in the product is reduced to the calculated one.
At the design pressure in the product, it is allowed to be at the hydraulic stand:
testers;
defectoscopists;
representatives of the technical control department (TCD);
responsible for the safe conduct of work - foreman, senior foreman, head of the site;
heads of departments;
employees of leading technical departments;
customer representatives.
These persons must undergo special training or appropriate instruction in accordance with GOST 12.0.004.
4.2.8. When using flaw detection equipment with sources of ultraviolet radiation, eye irradiation and skin workers are not allowed.
4.2.9. The tester is obliged to interrupt the test, turn off the pumps that create pressure, or shut off the valves of the pipelines supplying pressure to the product (when using one pump for several workplaces) and open the pressure relief valves when:
interruption in the supply of working pressure;
reaching a pressure in the product or pipelines higher than permitted despite compliance with all the requirements specified in the instructions;
failure of pressure gauges or other indicating instruments during pressure rise;
actuation of safety devices;
the occurrence of water hammer in the pipeline or product, the appearance of vibration;
detection of leaks, cracks, bulges or sweating in welds in the tested product, technological equipment, pipelines;
leakage through the drainage holes, which serves as a signal to terminate the test;
destruction of the tested product;
fire, etc.
4.2.10. After depressurizing the system, before disassembling the flange connections, it is necessary to remove the working fluid from the product and the system.
4.2.11. When dismantling the tooling, the nuts of the bolted connections should be removed, gradually loosening the diametrically opposite ones ("crosswise"), and pay attention to the integrity sealing elements to prevent them from getting into the internal cavities of the product.
4.2.12. Waste working fluid containing chemical substances, must be neutralized and/or cleaned before being discharged into the sewer network.
Discharge into the sewer of working liquids containing phosphors, preservatives, etc., which have not undergone neutralization and (or) purification, is prohibited.
When working with a solution of bleach at the site of hydrotesting, the system of general exchange supply and exhaust ventilation must be turned on. The exhaust pipe of the ventilation system must be located directly above the container with the bleach solution.
Chlorine lime that has fallen on the floor should be washed off with water into the sewer drain.
All work with bleach should be carried out in goggles, a canvas suit, rubber boots and gloves, with a gas mask on.
4.2.13. Removal from the skin of phosphors based on fluorescein and its solutions (suspensions) must be done with soap and water or 1 - 3% aqueous ammonia solution.
Upon completion of work with phosphors, personnel must thoroughly wash their hands with warm water and soap.
ANNEX 1
PROTOCOL OF APPROVALS
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1. CHARACTERISTICS OF THE HYDROSTAND Design pressure, MPa (kgf / cm 2) ____________________________________________ Permissible working pressure, MPa (kgf / cm 2) __________________________________ Design temperature, °C _________________________________________________ Characteristics of the working agent ______________________________________________ (water, neutral liquids, etc.) ___________________________________________ 2. LIST OF INSTALLED UNITS 3. LIST OF INSTALLED FITTINGS AND MEASURING INSTRUMENTS 4. INFORMATION ABOUT CHANGES IN THE STAND DESIGN
5. list of replacement units, fittings, MEASURING INSTRUMENTS 6. INFORMATION ABOUT PERSONS RESPONSIBLE FOR THE STAND 7. MARKS ON THE PERIODIC SURVEYS OF THE BENCH PRINCIPAL DIAGRAM OF THE HYDROSTAND ACT OF MANUFACTURING HYDROSTAND Company ___________________ Manufacturing shop _______________ Stand for hydraulic tests in accordance with the drawing No. ___________________________ and TU _____________________________ and accepted by the QCD of shop No. ________________ Beginning manufacturer's shop ____________________________________________ (stamp) |
