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The value of the test hydraulic pressure for vessels and apparatus operating at sub-zero temperatures, is taken the same as at 20 C. Vessels and apparatus operating under pressure below 0 07 MPa should be tested at / Jnp 0 2 MPa. When testing vertical apparatus in a horizontal position, hydrostatic pressure is added to the test pressure.

The value of the test hydraulic pressure during testing is taken as 1 25 working pressure, but not less than the working pressure plus 3 atm at an operating pressure above 5 atm, and at an operating pressure below 5 atm, 1 5 working pressure, but not less than 2 atm.

The value of the test hydraulic pressure for vessels and apparatus operating at sub-zero temperatures is assumed to be the same as at 20 ° C. When testing vertical apparatus in a horizontal position, hydrostatic pressure is added to the test pressure.

The value of the test hydraulic pressure during a hydraulic test is taken depending on the operating pressure according to the instructions technical documentation for the manufacture and repair of the system.

The value of the test hydraulic pressure is set for pipelines directly connected to the boiler (there are no disconnecting devices between the boiler and the line), according to the test pressure in the boiler; and for all other pipelines - 1 25 from the working pressure adopted by the project for this pipeline.

If the value of the trial hydraulic pressure is not indicated, then it is allowed to test the valve with one and a half nominal pressure, the value of which is indicated on the valve body.

Each cylinder on a spherical surface must have clearly stamped stamps: brand of the manufacturer, number of the cylinder; the actual weight of the cylinder with an accuracy of 0 2 kg; the value of the test hydraulic pressure in kg.

Vessels with a wall operating temperature of more than 400 C, except for cast ones, are subjected to a hydraulic test at the manufacturing plant at a pressure exceeding the operating pressure by at least 15 times. The value of the trial hydraulic pressure, exceeding the working one by 15 times, is established by the design organization.

All fittings - taps, valves and gate valves - are tested hydraulically before installation. The value of the test hydraulic pressure is indicated in the catalogs for fittings.

Vessels intended for operation with a wall temperature above 400 C, except for cast ones, are subjected to a hydraulic test at the factory with a pressure exceeding the working pressure by at least 15 times. The value of the trial hydraulic pressure; exceeding 1 5 r, is established by the design organization.

Vessels intended for operation with a wall temperature above 400, except for cast ones, are subjected to a hydraulic test at the factory with a pressure exceeding the working pressure by at least 15 times. The value of the test hydraulic pressure exceeding 1 5 r is established by the design organization.

Vessels intended for operation at a wall temperature above 400 C, except for cast ones, are subjected to a hydraulic test at the manufacturer's plant at a pressure exceeding the working pressure by at least 15 times. The value of the test hydraulic pressure exceeding 1 5 r is established by the design organization.

Vessels intended for operation with a wall temperature above 400, except for cast ones, are subjected to a hydraulic test at the factory with a pressure exceeding the working pressure by at least 15 times. The value of the test hydraulic pressure exceeding 1 5 R is established by the design organization.

After welding, all products are tested for strength and density by hydraulic pressure. For vessels with a working pressure of less than 5 atm, the value of the test hydraulic pressure is taken 50% more than the working pressure, but not lower than 2 atm. At a working pressure of more than 5 atm, the test hydraulic pressure must exceed the working pressure by 25% (but not less than 3 atm). For vessel elements operating at a wall temperature of over 450, regardless of the wall temperature, and at a pressure of over 50 atm, as well as in the manufacture of vessels from alloyed steel that accepts hardening in air or is prone to the formation of intergranular cracks, metallographic studies of welded samples from control plates or joints, if these tests are provided for by the specifications for manufacturing.

The final operation of the survey of the apparatus is its hydraulic strength test after installation in the design position or, most often, immediately before installation on the site. preparatory work. The place of hydrotesting is determined by the design features of the apparatus. Hydrotesting is carried out in the presence of an inspector of the State Gortekhnadzor. The procedure for conducting hydraulic tests is almost independent of design features equipment and is determined by the rules of gosgortekhnadzor, therefore, the description of this work below is mandatory for all devices high pressure. The value of the test hydraulic pressure is usually regulated specifications or project guidelines. In the absence of these instructions, hydrotesting is carried out test pressureРpr 25Р, where Р is the working pressure in the apparatus.

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RESOLUTION of the Gosgortekhnadzor of the Russian Federation dated 10-06-2003 80 ON APPROVAL OF THE RULES FOR THE DEVICE AND SAFE OPERATION OF TECHNOLOGICAL ... Relevant in 2017

8.2. Hydraulic strength and density test

8.2.1. Hydraulic testing of pipelines should be carried out mainly in the warm season at a positive ambient temperature. For hydraulic tests, as a rule, water with a temperature not lower than plus 5 degrees should be used. C and not higher plus 40 degrees. C or special mixtures (for high pressure pipelines).

If a hydraulic test is performed at an ambient temperature below 0 degrees. C, measures must be taken to prevent freezing of the water and ensure that the pipeline is safely emptied.

After the end of the hydraulic test, the pipeline should be completely emptied and blown through until the water is completely removed.

8.2.2. The value of the test pressure for strength (hydraulic or pneumatic method) is set by the project and must be at least:

1.25 x P x	[sigma]20	, but not less than 0.2 MPa (2 kgf/cm2),
	[sigma]t

P - design pressure of the pipeline, MPa;

[sigma] 20 - allowable stress for the pipeline material at 20 degrees. WITH;

[sigma]t - allowable stress for the pipeline material at the maximum positive design temperature.

In all cases, the value of the test pressure should be taken such that the equivalent stress in the pipe wall at the test pressure does not exceed 90% of the yield strength of the material at the test temperature.

The value of the test pressure for strength for vacuum pipelines and pipelines without overpressure for toxic and explosive environments should be taken equal to 0.2 MPa (2 kgf/cm2).

8.2.3. Valves should be subjected to a hydraulic pressure test after manufacture or repair.

8.2.4. When filling the pipeline with water, the air must be removed completely. The pressure in the pipeline under test should be gradually increased. The rate of pressure rise must be specified in the technical documentation.

8.2.5. Tapping of pipelines during testing is not allowed.

8.2.6. The pipeline under test may be filled with water directly from the water supply or with a pump, provided that the pressure created in the pipeline does not exceed the test pressure.

8.2.7. The required pressure during the test is created by a hydraulic press or a pump connected to the pipeline under test through two shut-off valves.

After reaching the test pressure, the pipeline is disconnected from the press or pump.

The test pressure in the pipeline is maintained for 10 minutes (strength test), after which it is reduced to operating pressure, at which a thorough inspection of the welds is carried out (density test).

At the end of the inspection, the pressure is again increased to the test pressure and maintained for another 5 minutes, after which it is again reduced to the working one and the pipeline is again carefully inspected.

The duration of the density test is determined by the time of inspection of the pipeline and checking the tightness of detachable joints.

After the end of the hydraulic test, all air vents on the pipeline must be opened and the pipeline must be completely emptied of water through the appropriate drains.

8.2.8. The results of a hydraulic test for strength and density are considered satisfactory if during the test there were no ruptures, visible deformations, pressure drops on the pressure gauge, and in the base metal, welds, valve bodies, detachable connections and no leaks or fogging were found in all the tie-ins.

8.2.9. Simultaneous hydraulic testing of several pipelines mounted on common carriers building structures or overpass, is allowed if it is established by the project.

169. Hydraulic test in order to check the density and strength of equipment under pressure, 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 site (additional production) 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 production) 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 production) 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.

170. Vessels having protective covering or insulation is subjected to a hydraulic test prior to coating or insulation.

Vessels with an outer casing are subjected to a hydraulic test before the casing is installed.

It is allowed to subject enameled vessels to a hydraulic test with working pressure after enamelling.

171. The minimum value of the test pressure during a hydraulic test for steam and hot water boilers, superheaters, economizers, as well as for pipelines within the boiler limit 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.

When conducting a hydraulic test of drum boilers, as well as their superheaters and economizers, the pressure in the boiler drum is taken as the operating pressure when determining the value of the test pressure, and for drumless and once-through boilers with forced circulation- pressure of feed water at the inlet to the boiler, established by the project documentation.

The maximum value of the test pressure is set by calculations for the strength of steam and hot water boilers.

The value of the test pressure (between the maximum and minimum) should ensure the greatest detection of defects in the boiler or its elements subjected to hydraulic testing.

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:

Where P - design pressure in case of additional production at the place of operation, in other cases - working pressure, MPa;

Permissible 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, branch pipes, 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.

If, in order to ensure the conditions of strength and tightness during testing, it becomes necessary to increase the diameter, quantity or replace the material of bolts (studs) of flange connections, it is allowed to reduce the test pressure to maximum value, at which, during testing, the conditions for the strength of bolts (studs) are provided without increasing their diameter, quantity, or replacing material.

If the vessel as a whole or individual parts of the vessel operate in the creep temperature range and the allowable stress for the materials of these parts at the design temperature is determined on the basis of the ultimate strength or creep limit, it is allowed in formulas (1), instead of using the allowable stress at the design temperature , obtained only on the basis of time-independent characteristics: yield strength and tensile strength without taking into account creep and long-term strength.

During hydraulic testing of technological pipelines, the value of the test pressure is determined by the formula (1) .

173. The value of test pressure during hydraulic testing of cast and forged vessels is determined by the formula

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.

174. Hydraulic testing of vessels and parts made of non-metallic materials with an impact strength of more than 20 J / cm2 must be carried out with a test pressure determined by the formula:

Hydraulic testing of vessels and parts made of non-metallic materials with an impact strength of 20 J/cm2 or less must be carried out with a test pressure determined by the formula:

175. The value of test pressure during hydraulic testing of cryogenic vessels in the presence of vacuum in the insulating space is determined by the formula:

176. Hydraulic testing of metal-plastic vessels must be carried out with a test pressure determined by the formula:

Where - the ratio of the mass of the metal structure to the total mass of the vessel;

1.3 - for non-metallic materials with an impact strength of more than 20 J/cm2;

1.6 - for non-metallic materials with an impact strength of 20 J/cm2 or less.

177. Hydraulic testing of vessels installed vertically may be carried out in a horizontal position; in this case, the strength of the vessel body must be calculated taking into account the accepted method of support for hydraulic testing.

In combined vessels with two or more working cavities designed for different pressures, each cavity must be subjected to a hydraulic test with a test pressure determined depending on the design pressure of the cavity.

The procedure for testing such vessels must be established by the developer of the design technical documentation and specified in the vessel's operating manual.

178. The minimum value of test pressure during hydraulic testing of pipelines of steam and hot water, their blocks and individual elements should be 1.25 working pressure, but not less than 0.2 MPa. Fittings and fittings of pipelines must be subjected to a hydraulic test with test pressure in accordance with the technological documentation. The maximum value of the test pressure is set by calculations for the strength of pipelines.

The value of the test pressure (between the maximum and minimum) should ensure the greatest detection of defects in the pipeline or its elements subjected to hydraulic testing.

179. For hydraulic testing of equipment under pressure, water should be used. 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.

During hydraulic testing of steam pipelines operating at a pressure of 10 MPa and above, the temperature of their walls must be at least 10 °C.

During hydraulic testing of steam and hot water boilers, the upper limit of water temperature can be increased in agreement with the design organization up to 80 °C. If the metal temperature of the top of the drum exceeds 140 °C, filling it with water for hydraulic testing is not allowed.

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.

The exposure time under test pressure for steam and hot water boilers, including electric boilers, steam and hot water pipelines, as well as vessels assembled at the installation site, is set by the manufacturer in the operating manual and must be at least 10 minutes.

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.

For cast, non-metallic and multilayer vessels, regardless of the wall thickness, the holding time must be at least 60 minutes.

The exposure time of process pipelines under test pressure during a hydraulic test must be at least 15 minutes.

If the process pipeline is tested together with the vessel (apparatus) to which it is connected, the exposure time is taken according to the time required for the vessel (apparatus).

181. After holding under test pressure, the pressure decreases to a value justified by the strength calculation, but not less than the working pressure at which visual control is carried out outer surface equipment and all its detachable and non-detachable connections.

182. During a hydraulic test, the boiler is considered to have passed the test if it is not found:

A) visible residual deformations;

B) cracks or signs of rupture;

C) leaks in welded, detachable joints and in the base metal;

The equipment and its elements, in which defects are revealed during the hydraulic test, after they are eliminated, are subjected to repeated hydraulic tests with test pressure.

186. Hydraulic testing of technological pipelines with a pressure of not more than 10 MPa, as well as vessels, may be replaced by pneumatic testing (compressed air, inert gas or a mixture of air with inert gas), subject to simultaneous control by the method of acoustic emission.

Test pressure during pneumatic testing should be determined by the formula:

Where: P - working pressure.

If the probability of brittle fracture during a pneumatic test is greater than under operating conditions, and its consequences represent a significant danger, the test pressure must be reduced to a technically justified level, but not less than the operating pressure.

In technically justified cases provided by the manufacturer, when conducting pneumatic tests, during operation of the equipment, it is allowed to use gaseous working environment test object, while the test pressure is determined by the formula (7) .

The exposure time of the vessel (process pipeline) under test pressure during pneumatic testing must be at least 15 minutes. and indicated in the technological documentation.

After exposure under test pressure, the pressure is reduced to a value justified by the strength calculation, but not less than the operating pressure, at which visual inspection of the outer surface and the tightness of welded and detachable joints are carried out.