GOST 14782_86 - UT - Welded Joints
Short Description
UT on welded joints...
Description
GOST 14782-86. Non-destructiv Non-destructive e testing. Welded joints.Ultrasonic methods GOST 14782-86 Group B09
Interstate standards
Non-destructive testing Welded joints
Ultrasonic methods Nondestructive testing. Welded joints. Ultrasonic methods
ISS 25.160.40 OKS 0072 Introduced 1988-01-01
INFORMATION INFORMATI ON INFORMATION 1. DEVELOPED AND INTRODUCED by the Ministry of Railways of the USSR 2. approved and put into force by the Decision of the USSR State Committee on Standards of December 17, 1986 N 3926 3. INSTEAD GOST 14782-76, GOST 22368-77 4. The standard takes into account the requirements of ST SEV 2857-81 and 5246-75 Recommendations CMEA PC
5. REFERENCE regulatory and technical documents Reference document to which reference is made
Item number, the application
GOST 8.315-97
Appendix 1
GOST 8.326-89
13
GOST 12.1.001-89 12.1.001-89
5.1
GOST 12.1.003-83 12.1.003-83
5.3
GOST 12.1.004-91 12.1.004-91
5.4
GOST 12.2.003-91 12.2.003-91
5.1
GOST 12.3.002-75 12.3.002-75
5.1
GOST 1050-88
1.4.2, 1.4.4, Annex 4
GOST 2789-73 2789-73
2.2
GOST 14637-89
1.4.2, 1.4.4, Annex 4
GOST 17622-72 17622-72
1.4.1
GOST 18576-85
1.5, 2.9.1, 2.9.2, Annex 2
GOST 23829-85
Appendix 1
GOST 25346-89
14
GOST 25347-82 25347-82
2.9.3
GOST 26266-90
13
6. REVISED. May 2005
1. This standard specifies methods of ultrasonic testing of butt, corner, lap and T-joints made of arc, electroslag, gas, gazopressovoy, electron beam and flash-butt welding in welded structures of metals and alloys to detect cracks, lack of penetration, pores, and non-metallic metallic inclusions. The standard does not specify the methods of ultrasonic testing of welding.
The need for ultrasonic testing, the volume control and the size of unacceptable defects are established in the standards or technical specifications for products. Explanation of terms used in this standard are given in Appendix 1.
1. CONTROLS eleven. When control must be used: Ultrasonic flaw pulse (hereinafter - flaw) is not lower than the second group piezoelectric transducers; Standard samples for setting flaw; aids and devices for compliance with the parameters of scanning and measuring the characteristics characteri stics of the detected defects. Flaw and standard samples used for monitoring should be certified and believed in the prescribed manner. Allowed to use the flaw elektromagnitoakustichesk elekt romagnitoakusticheskimi imi converters. converter s. 12. To control, use flaw, complete straight and angle beam probes with an attenuator, allowing to determine coordinates of the reflecting surface. Significance level attenuator should be no more than 1 dB. Allowed to use a flaw attenuator attenua tor stage attenuation at tenuation value which is 2 dB attenuator at tenuator without flaw with the system of automatic measurement of the signal amplitude. 13. Piezoelectric transducers at a frequency of 0.16 MHz - according to GOST 26266. It is allowed to use non-standardized transducers GOST 8,326 *. 8,326 *. ________________ * On the territory of the Russian Federation are PR 50.2.009-94 **. 50.2.009-94 **. ** On the territory of the Russian Federation, the document is not valid. EffectiveTest Effective Test procedure reference materials or measuring instruments for the purpose of type approval, approval, Administrative Administrative Regulations Regula tions on the provision of t he Federal Agency for f or Technical Regulation and Metrology of the public service according to the type of reference materials or type of measuring instruments, instruments,requirements requirements for type approval mark reference materials or type of measuring and order their application, application, here and hereafter. - Note manufacturer's database.
1.3.1. Piezoelectric transducers are selected taking into account: shape and dimensions of the electroacoustic transducer; of the prism material and the propagation velocity of ultrasonic longitudinal wave at temperature (20 ± 5) ° C; middle way of ultrasound in the prism. 1.3.2. The frequency of ultrasonic vibration emitted inclined transducers must not vary from the nominal value by more than 10% in the range communication. 1.25 MHz by more than 20% in the range up to 1.25 MHz. 1.3.3. The position mark corresponding to the exit point of the beam must not differ from the actual more than ± 1 mm. 1.3.4. The working surface of the converter in the control of welded joints of cylindrical products or other curved shall comply with the technical documentation for control, duly approved. 14. Standard samples of S-1 (chert.1), CO 2 (chert.2) and CO-3 (chert.4) should be used for measuring and testing equipment and basic parameters of control in pulse-echo method and a combined scheme incorporating a piezoelectric transducer flat work surface to a frequency of 1.25 MHz or more, provided that the width of the transducer does not exceed 20 mm. In other cases, the main parameters to check the equipment and the control should be used industry standard samples (enterprise).
Chert.1 1 -
hole for determining the relative sensitivity; 2 - a wall; 3 - the basis; 4 - a lining that protects the hole 1 from pollution; 5 - holes to determine the resolution, 6 - slots to determine the
resolution;
7 -
groove for determining the error of depth gauge;
- the time measured to whole
numbers of microseconds Notes: 1. Limit deviations for linear dimensions of the sample - not lower than 14 th quality class accordingto GOST 25346. 2. Tolerances diameter holes in the standard sample should not be lower than 14 th quality class according to GOST 25346.
1.4.1. Standard sample SB-1 (see. Chert.1) is used for determining the relative sensitivity, resolution, and verification error flaw depth gauge. Sample CO-1 must be made of organic glass brand TOSP of GOST 17622. The propagation velocity of longitudinal ultrasonic waves at a frequency of (2,5 ± 0,2) MHz at a temperature of (20 ± 5) ° C should be equal to (2670 ± 133) m / s. Measured with an accuracy of better than 0.5% the speed must be specified in the certificate for the sample. The amplitude of the pulse of the bottom third of the thickness of the specimen at a frequency of (2,5 ± 0,2) MHz and temperature (20 ± 5) ° C should not differ by more than ± 2 dB from the bottom of the third amplitude pulse in the corresponding original sample certified by state metrological service. The attenuation coefficient of longitudinal ultrasonic waves in the starting sample must be in the range of 0.026 to 0.034
mm.
Allowed to use samples from the organic glass according chert. 1 in which the amplitude of the
third pulse of the bottom thickness of the sample differs from the amplitude of the corresponding pulse in the original sample by more than ± 2 dB. At the same time, and in the absence of the original sample to sample attestation must be accompanied by a certificate schedule on Schedule 2 or table amendments, taking into account the variation of attenuation coefficient and the effect of temperature. 1.4.2. Standard sample SB-2 (see. Chert.2) is used for determining the relative sensitivity of the dead zone, depth gauge error, the angle of
the input beam width of the main lobe, the
pulse conversion coefficient at the control joints of mild and low-alloy steels, as well as to determine the utmost sensitivity.
1 -
hole for determining the angle of the input beam width of the main lobe, the conventional
and the ultimate sensitivity; 2 - the hole to check dead zone; 3 - converter; 4 - a block of steel or steel 20 3 Chert.2
Sample CO 2 must be made of steel grade 20 to GOST 1050 or steel 3 to GOST 14637. The speed of propagation of longitudinal waves in the sample at a temperature of (20 ± 5) ° C should be equal to (5900 ± 59) m / s. Measured with an accuracy of better than 0.5% the speed must be specified in the certificate for the sample. When testing the compounds of the metal, differing in the acoustic characteristics of the lowcarbon and low-alloy steels, for the determination of the angle of the input beam width of the main lobe, the dead zone, and the maximum sensitivity of the standard to be applied sample SB-2A (chert.3).
1 -
hole for determining the angle of the input beam width of the main lobe, the conventional
and the ultimate sensitivity; 2 - the hole to check dead zone; 3 - converter; 4 - a block from a controlled metal; 5 - the scale; 6 - the screw Chert.3
Requirements for the sample material, the number of holes 2 and the distances
determining
the center of the hole 2 in the sample SB-2A must be specified in the technical documentation control. Scale values of the input angle of the beam of standard samples CO-2 and CO-2A calibrated in accordance with the equation . where
- the depth of the hole center 1.
Zero the scale must coincide with the axis passing through the center of the hole diameter (6 ± 0.3) mm perpendicular to the surfaces of the sample to an accuracy of ± 0,1 mm. 1.4.3. The propagation time of the ultrasonic vibration in the forward and reverse directions, the standard samples on SB-1 and SB-2, should be (20 ± 1) s. 1.4.4. Standard sample SB-3 (see. Chert.4) should be used to determine the exit point 0 of the ultrasonic beam, the boom
of the converter.
Chert.4
It is allowed to use the standard sample SB-3 to determine the propagation time of the ultrasonic vibration transducer in the prism of Annex 3. Standard sample SB-3 are made of steel grade 20 to GOST 1050 or steel 3 to GOST 14637.The speed of propagation of longitudinal waves in the sample at a temperature of (20 ± 5) ° C to be (5900 ± 59) m / s. Measured with an accuracy of better than 0.5% the speed must be specified in the certificate for the sample. On the side of the working surface of the sample and must be engraved with the risks passing through the center of the semicircle and the axis of the work surface. In both sides of the scratches on the surface of the coated side of the scale. Zero the scale must coincide with the center of the sample to an accuracy of ± 0,1 mm. When testing compounds of the metal, the speed of propagation of transverse waves in which less than the velocity of shear wave of steel grade 20 and, using a transducer with an angle of incidence close to the second critical angle in steel 20, for determining the point of exit and the arrows converter should be applied standard sample enterprise with 3A made of metal controlled by chert.4. Requirements for metal sample SB-3A must be indicated in the technical documentation for the control, duly approved. 15. Approved for determining the relative sensitivity, depth gauge error, the location of the point of exit and entry angle, width of the main lobe to use the sample CO-2P GOST 18576 * or composition of samples of CO-2 and CO-2P with the introduction of additional holes with a diameter of 6 mm.
________________ * From 1 January 2002 entered into force with GOST 18576-96 (hereafter).
16. The flaw detector for mechanical controls should be provided to ensure systematic verification of the parameters determining the efficiency of the equipment. The list of parameters and the order of testing shall be specified in the technical documentation for the control, duly approved. It is allowed to use to test the sensitivity of the conventional standard samples or SB-1 or CO 2, or enterprise standard samples referred to in the technical documentation for the control, duly approved. 1.7. It is allowed to use the equipment without the assistive devices and devices for compliance with the parameters of the scan manually by moving the transducer to measure the characteristics of the detected defects.
2. GETTING CONTROL 2.1. Welded joints are prepared by ultrasonic testing without the compound external defects. The shape and dimensions of the weld zone should allow you to navigate within the inverter, providing an acoustic axis of the transducer sonic welded joint or a part thereof, to be controlled. 2.2. The surface of the connection on which the transducer is moved, should not have dents and irregularities on the surface must be removed spatter, scale and flaking paint, dirt. When machining a compound provided a process for the manufacture of welded construction, the surface must not be less than
40 microns in GOST 2789.
Requirements for permissible waviness and surface preparation specified in the technical documentation for the control, duly approved. Admissibility presence neotslaivayuscheysya scale, paint and dirt under the control of EMAtransducers indicated in the technical documentation for the control, duly approved. 2.3. Control of heat affected zone of the base metal within the displacement transducer on the absence of bundles should be carried out in accordance with the technical documentation control, duly approved, if the control of metal before welding is not produced. 2.4. The welded joint should be identified and separated into sections so that clearly establish the location of the defect on the length of the seam. 2.5. Pipes and tanks to control the reflected beam must be released from the liquid. Allowed to control the pipes and tanks with a liquid according to the procedure stipulated in the technical
documentation for the control, duly approved. 2.6. Angle input beam and limits movement of the transducer should be chosen so as to ensure the sonic weld section direct and reflected rays once or just a direct beam. The direct and reflected rays once should control joints, the size or width of the legs which allow sounding acoustic axis of the inspected section of the inverter. Allowed to control the welds repeatedly reflected beam. 2.7. The duration of the sweep should be installed so that the largest part of the sweep on the screen CRT consistent path of the ultrasonic pulse in the metal-controlled part of the joint. 2.8. The main parameters of the control: 1) the wavelength or frequency of the ultrasonic oscillations (flaw); 2) sensitivity; 3) the position of the exit point of the beam (arrow converter); 4) the angle of the ultrasonic beam entering into the metal; 5) the error depth gauge (coordinate measurement error); 6) the dead zone; 7) range resolution and (or) the front; 8) features an electro-acoustic transducer; 9) minimum proof defect size, fixed by a given scanning speed; 10) the pulse width of the flaw detector. The list of parameters to be checked, numerical values, methods and frequency of verification should be addressed in the technical documentation for control. 2.9. The main parameters in accordance with 2.8, listing 1-6, should be checked by standard samples S-1 (chert.1), CO 2 (or CO-2A) (chert.2 and 3), CO-3 (Fig .4), CO-4 (Appendix 4), and the standard model of the enterprise (chert.5-8). Requirements for certified reference materials businesses, as well as the method of verification of the main control parameters should be specified in the technical documentation for the
control, duly approved. 2.9.1. The frequency of the ultrasonic vibration be measured by electronic methods analyzing the spectrum of the echo at the transducer from a concave cylindrical surface of the standard sample SB-3 or by measuring the period of oscillations in the duration of the echo pulse by wideband oscilloscope. Allowed to determine the wavelength and frequency of the ultrasonic waves emitted by the transducer inclined, the interference method modeled CO-4 according to the recommended application and 4 GOST 18576 (Appendix 3). 2.9.2. Conditional sensitivity control echo method should be measured by the standard model of SB-1 millimeters or standard sample SB-2 in decibels. Measurement sensitivity of conventional standard model SB-1 is carried out at a temperature installed in the technical documentation for the control, duly approved. Conditional sensitivity control shadow and mirror-shadow method to measure the defect-free area of a welded connection or a standard sample of companies in accordance with GOST 18576. 2.9.3. The maximum sensitivity of the flaw detector with the transmitter to be measured in square millimeters of the bottom area of 1 hole in the standard sample of the enterprise (see. Chert.5) or determined by ARA (or SKH) -diagram. Allowed the company instead of the standard sample with a hole with a flat bottom to apply the standard samples of the enterprise segment with reflectors (see. Chert.6) or enterprise standard samples with corner reflectors (see. Chert.7), or a standard sample of enterprises with a cylindrical bore (see. Features .8). The angle between the plane of the bottom of one hole or the plane of contact surface of the sample should be
one segment
and the
() ° (see. Chert.5 and 6).
Tolerances on the diameter of the holes in the standard sample of enterprises shall be ± chert.5
of GOST 25347.
1 -
the bottom of t he hole; 2 - converter; 3 - a block from a controlled metal; 4 - acoustic axis Chert.5
1 -
a plane segmented reflector; 2 - converter; 3 - a block from a controlled metal; 4 - acoustic axis Chert.6
1 -
plane corner reflector 2 - converter; 3 - a block from a controlled metal: 4 - acoustic axis Chert.7
The height of
the segmental reflector must be greater than the length of the ultrasonic
wave; the ratio of The width
the segmented reflector shall be greater than 0.4.
and height of the
ultrasound;the ratio Limiting sensitivity
corner reflector must be longer than the length of the
should be greater than 0.5 and less than 4.0 (see. chert.7). () in square millimeters, as measured by the standard model with a
corner reflector
area, calculated by the formula .
where the
- coefficient for steel, aluminum and its alloys, titanium and its alloys, depending on
angle, specified in the technical documentation for the control, duly approved, subject to
the application 5. A cylindrical hole 1 diameter
= 6 mm to adjust the limit of sensitivity must be made with a
tolerance of 0.3 mm at a depth of
1 -
= (44 ± 0,25) mm (see. Chert.8).
the cylindrical bore; 2 - converter; 3 - controlled unit of metal; 4 - acoustic axis Chert.8
The maximum sensitivity of the flaw detector on the model of a cylindrical bore should be determined in accordance with Annex 6. In determining the maximum sensitivity of the amendment should be introduced, taking into account the difference of purity processing and curvature of the surfaces of the standard sample and controlled connection. When using the diagrams as a reference signal used the echoes from the reflectors in the standard samples and SB-1 or CO 2, or CO 2 A or CO-3, as well as on the bottom surface or the dihedral angle in a controlled item or standard the sample companies. At the control of welded joints of thickness less than 25 mm in size, and orientation of the cylindrical hole in the standard sample of companies used to set the sensitivity to indicate in the technical documentation for the control, duly approved. 2.9.4. The angle of entry of the beam shall be measured according to standard models of CO 2 or CO-2A, or the standard model of the enterprise (see. Chert.8). Angle input of more than 70 ° measured at a temperature control. The angle of entry of the beam under the control of welded joints of thickness greater than 100
mm is determined in accordance with the technical documentation control, duly approved. 2.10. Features electroacousticthe converter must be checked on the normative and technical documentation for the equipment, duly approved. 2.11. The minimum size of a conditional defect which is fixed at a predetermined rate control should be determined on a standard sample of companies in accordance with the technical documentation control, duly approved. It allowed the determination of the minimum size to use conditional electronic equipment that simulates the signals from the defects of a given size. 2.12. The pulse duration is determined by the flaw detector wideband oscilloscope by measuring the duration of the echo signal at 0.1.
3. CONDUCT OF CONTROL 3.1. When testing of welded joints should be used echo pulse, shadow (mirror-shadow) or echo-shadow techniques. When the pulse-echo method is used combined (chert.9) separate (chert.10 and 11) and duals (chert.12 and 13) of the switching converters.
Chert.9
Chert.10
Chert.11
Chert.12
Chert.13
When the shadow method applied separately (chert.14) circuit switching converters.
Chert.14
When echo shadow technique used duals (chert.15) circuit switching converters.
Chert.15
Note. On chert.9-15; receiver.
- output to a generator of ultrasonic vibrations;
- output to the
3.2. Butt welds prozvuchivat schemes should be given to chert.16-19, T-joints - the schemes listed in the chert.20-22 and overlap joints - the schemes listed in the chert.23 and 24.
Chert.16
Chert.17
Chert.18
Chert.19
Chert.20
Chert.21
Chert.22
Chert.23
Chert.24
It is allowed to use other schemes listed in the technical documentation for the control, duly approved. 3.3. Acoustic coupling piezoelectric transducer controlled metal should establish contact or immersion (slot) input methods of ultrasonic vibrations. 3.4. Searching defect sensitivity (conditional or marginal) to exceed a predetermined value set in the technical documentation for the control, duly approved. 3.5. Sonic welded joint is performed according to the method of longitudinal and (or) transverse displacement transducer with a constant or a changing angle of the input beam. Scan method must be set in the technical documentation for the control, duly approved.
3.6. Steps scan (longitudinal
or
transverse) was determined based on the specified
search sensitivity exceeding the sensitivity of the evaluation pattern converter and controlled thickness of the welded joint. Method for determining the maximum scanning steps and
shown in Annex 7. Over the nominal step scanning with manual controls, which should
be respected in the process of monitoring should be: .
3.7. The method, the main parameters, circuit switching converters, the input method of the ultrasonic vibration testing schemes, as well as recommendations for the separation of false signals and the signals from flaws should be indicated in the technical documentation for the control, duly approved.
4. EVALUATION AND REGISTRATION OF THE RESULTS OF CONTROL 4.1. Evaluation of the test results 4.1.1. Assessment of quality of welded joints according to the ultrasonic testing should be carried out in accordance with the normative and technical documentation for the product, duly approved. 4.1.2. The main characteristics of the detected defect measured are:
1) the equivalent area of the defect
or the amplitude of
the echo signal from the defect
based on the measured distance to it; 2) the coordinates of a defect in the weld; 3) conditional size of the defect; 4) conditional distance between defects; 5) the number of defects in a certain length of the connection. Measured characteristics used to assess the quality of specific compounds, to be indicated in the technical documentation for control, duly approved. 4.1.3. The equivalent area of the defect must be determined in the amplitude of the echo signal by comparing it with the amplitude of the echo from the reflector in the sample or by using diagrams provided calculated convergence with experimental data at least 20%. 4.1.4. Conventional dimension are detected defect (chert.25): 1) The notional
length;
2) conditional
width;
3) conditional
height.
Conditional length
in millimeters measured along the length of the area between the
extreme positions of the transducer is moved along the seam oriented perpendicular to the axis of the seam. Conditional width
in millimeters is measured along the length of the area between the
extreme positions of the transducer being moved in the plane of incidence. Conditional height
in millimeters or microseconds is measured as the difference between
the values of the depth of the defect in the extreme positions of the transducer moving in the plane of incidence. 4.1.5. When measuring the size of
conventional,, for the extreme positions of the
transducer take those in which the amplitude of the echo signal from the detected defect or 0.5 of the maximum value, or reduced to a level corresponding to a predetermined value sensitivity.
The end positions are allowed to take those in which the amplitude of the echo signal from the detected defect is specified portion of from 0.8 to 0.2 of the maximum value. The accepted level values must be specified at time of inspection results. Conditional width
and height of a conditional
defect is measured in the cross section of
the compound where the echo from the defect has the largest amplitude at the same extreme positions of the transducer. 4.1.6. Conditional distance
(see. Chert.25) between defects measure the distance between
the extreme positions of the transducer, which was determined at the conditional extension of two adjacent defects.
Chert.25
4.1.7. An additional feature of the detected defect is its configuration and orientation. To estimate the orientation and configuration of the defect detected using: 1) Comparison of conventional size measured values of conventional size
and and
identified defect with the calculated and omni-directional reflector positioned at the
same depth as the defect is identified.
When measuring the size of
conventional,
and, for the extreme positions of the
transducer take those in which the amplitude of the echo signal of a predetermined portion of 0.8 to 0.2 of the maximum values stipulated in the technical documentation for the control, duly approved; 2) comparing the amplitude of the echo signal
reflected from the defect detected from the
back seam of neighbor transmitter with an amplitude of the echo
signal, which has
undergone specular reflection from the inner surface of the compound received and the two transducers (see. Chert.12);
3) comparison of the contingent dimensions of the defect detected size of conventional cylindrical
with the ratio of the
reflector;
4) comparing the second central moment of conditional detected defect size and cylindrical reflector positioned at the same depth as the detected defect; 5) the amplitude-time parameters of the signal waves, diafragirovannyh to defect; 6) the spectrum of the signals reflected from the defect; 7) the coordinates of points on the surface reflecting a defect; 8) comparing the amplitude of the received signals from the defect and by omnidirectional reflectors in articulating defect at different angles. Necessity, possibility and method of estimating the configuration and orientation of the identified defect for the compounds of each type and size must be specified in the technical documentation for the control, duly approved. 4.2. Making the test results 4.2.1. The inspection results must be recorded in a log or imprisoned, or in the scheme of the welded joint, or in another document, which must contain: type of controlled compounds codes assigned to this product and weld, and the length of the inspected site; technical documentation, in accordance with which the control is performed; type of flaw; neprokontrolirovannye or incompletely after tests sections of welded joints to be ultrasonically inspected; monitoring results; date of inspection; surname radiographer. For more information to be recorded, as well as order processing and storage magazine (opinions) must be specified in the technical documentation for the control, duly approved.
4.2.2. Classification of butt welded joints as a result of ultrasonic inspection produced by Annex 8. Classification is stipulated in the technical documentation for the control, duly approved. 4.2.3. When abridged description of the test results should be every defect or group of defects entered individually and Labeling: a letter specifying the qualitative assessment of the admissibility of the defect equivalent area (echo amplitude) and conditional length (A or D, or B, or DB); letter qualitatively determining conditional defect length if it is measured in accordance with paragraph 4.7, listing 1 (D or E); a letter specifying the configuration of the defect, if it is set; digit number identifying the equivalent area of the defect identified,
uh, if it is measured;
digit number identifying the greatest depth of the defect, mm; figure defining conditional defect length, in millimeters; figure defining conditional defect width, mm; figure defining conditional defect height, mm or microseconds. 4.2.4. For brevity should apply the following notation: A - defect, equivalent area (echo amplitude) and the notional length of which is equal to or less than the permissible values; D - defect, equivalent area (echo amplitude) which exceeds the limit; B - defect conditional length greater than the maximum value;
G - defects, the length of which is
conditional;
E - defects, the length of which is
conditional;
In - group of defects, spaced at a
distance;
T - defects that are detected at the location of the transducer at an angle to the axis of the joint and not found at the location of the transducer perpendicular to the axis of the seam.
Conditional length for defects of type T and T is not specified. In shorthand numeric values are separated from each other and from the lettering hyphen. The need for shorthand used symbols and the order of their records are specified in the technical documentation control, duly approved.
5. SAFETY REQUIREMENTS 5.1. When carrying out ultrasonic testing products must engineerguided by GOST 12.1.001, GOST12.2.003, GOST 12.3.002, the rules of technical operation of electrical consumers and the rules of technical safety in the operation of electric consumers * approved Gosenergonadzor. ________________ * On the territory of the Russian Federation, the document is not valid. EffectiveCross-industry regulations on labor protection (safety) for the operation of electrical (POT R M-016-2001, RD 153-34.0-03.150-00). - Note manufacturer's database. 5.2. When the controls should comply with the requirements of "Sanitary norms and rules when working with equipment that produces ultrasound transmitted by contact on the hands working" N 2282-80 *, approved by the USSR Ministry of Health and safety requirements set out in the technical documentation of the applied equipment, approved in the established order. ________________ * On the territory of the Russian Federation, the document is not valid. EffectiveSanPiN 2.2.4. /2.1.8.582-96. - Note manufacturer's database. 5.3. The levels of noise generated in the workplace radiographer shall not exceed the permissible according to GOST 12.1.003. 5.4. In organizing the activities of control must comply with the requirements of fire safety GOST12.1.004.
ANNEX 1 (informative). EXPLANATION OF TERMS APPLICABLE TO THE STANDARD ANNEX 1 Reference Expression Defect
Determination A discontinuity or group centered discontinuities not provided design documentation and independent of the effects of the object from the other discontinuities.
Limiting Sensitivity control echo method
Sensitivity characterized equivalent minimum area (in
mm) of the reflector, which is still detected at a predetermined depth in the product at a given setting apparatus Relative sensitivity control echo method
The sensitivity, characterized by the size and depth of the detected artificial reflectors made in a sample of material with a specific acoustic properties. When ultrasonic testing of welds conditional sensitivit y is determined by the standard model of SB-1 or standard sample SB-2 or standard sample CO-2P . Conditional sensitivity of the standard sample SB-1 express the greatest depth (in millimeters) location cylindrical reflector, fixed by indicators flaw. Conditional sensitivity of the standard model of CO 2 (or CO-2P) express the difference in decibels between the indication of the attenuator when this setting flaw and the indication corresponding to the maximum weakening, in which a cylindrical hole with a diameter of 6 mm at a depth of 44 mm fixed indicators flaw
Acoustic axis
According to GOST 23829
Exit Point
According to GOST 23829
Boom converter
According to GOST 23829
Angle input
The angle between the normal to the surface on which the transducer, and a line connecting the center of a cylindrical reflector with a point of exit in the installation position of the transducer at which the amplitude of the echo signal from the reflector largest
Dead zone
According to GOST 23829
Range resolution (radiation)
According to GOST 23829
Resolution front
According to GOST 23829
A standard sample of companies
According to GOST 8.315
Industry standard sample
According to GOST 8.315
Surface Input
According to GOST 23829
Contact method
According to GOST 23829
Immersion method
According to GOST 23829
The error of the depth gauge
Accuracy of measurement known distance to the reflector
The second central moment of normalized
.
conditional size of the
defect, which is located at a depth of
wherein
- central point;
which determined time; path,
- scanning trajectory on
- the coordinate along the
- the signal amplitude at
point;
; - the average value of the coordinates for the dependence;
.
For symmetric dependencies
point
coincides
with the point corresponding to the maximum amplitude
ANNEX 2 (mandatory). METHOD OF CONSTRUCTION CERTIFICATE schedule to the standard sample of organic glass;EXAMPLES PRIMENINIYA CERTIFICATE graphics APPENDIX 2 Mandatory
Passport schedule communicates conditional sensitivity standard sample S-1 with the conditional sensitivity
() in millimeters on the original () in decibels for the standard model of
CO 2 (or CO-2P by GOST 18576) and the number of the reflector with a diameter of 2 mm in the attestation sample CO -1 at a frequency of ultrasonic vibrations (2,5 ± 0,2) MHz, temperature (20 ± 5) ° C and prism angles
= (40 ± 1) ° or
= (50 ± 1) ° for the particular type
of transducers. In the drawing, the points designated schedule for the initial sample SB-1.
To construct the corresponding chart for a particular sample of certified CO-1, does not comply with p.1.4.1 this standard, under the above conditions define the decibel difference between the
amplitude
and amplitude
of the reflectors 20 and N 50 2 mm in diameter in a sample of certified of a reflector diameter of 6 mm at a depth of 44 mm in the sample SB-2 (or
CO-2P):
;,
wherein
- the indication of the attenuator, an attenuation of the echo signal from a 6 mm
diameter holes in the sample SB-2 (or CO-2P) to a level at which the estimated conditional sensitivity dB;
- The indication of the attenuator, wherein the amplitude of the echo signal from the test hole number in Appraisee sample reaches a level at which a conditional estimated sensitivity dB.
The calculated values
mark the points on the graph and connect them by a straight line
(see the example of the construction. In the drawing). EXAMPLES OF CERTIFICATE graphics
Monitoring is carried out with the converter flaw on the frequency 2.5 MHz, with the angle of the prism
= 40 ° and the radius of the piezoelectric plate
6 mm manufactured in
accordance with the specifications approved by the established procedure. The flaw detector equipped with a sample of SB-1, serial number, a certificate from the graphic (see. Figure). 1. The technical documentation for the control given the sensitivity of conventional 40 mm. This sensitivity will be reproduced if the flaw adjust the hole N 45 in a sample S-1, serial number ____________. 2. Technical documentation for the control given conditional sensitivity of 13 dB. This sensitivity will be reproduced if the flaw adjust the hole N 35 in a sample S-1, serial number __________.
Annex 3 (informative). DETERMINATION propagation time of ultrasonic oscillations in PRISM CONVERTER Appendix 3 Reference Time
in microseconds of ultrasonic vibrations in the prism of the converter is equal to
ISS wherein
- the total time between the excitation pulse and the echo signal from the concave
cylindrical surface in the standard sample SB-3 for mounting the transducer to the position corresponding to the maximum amplitude of the echo signal; 33.7 microseconds - the propagation time of ultrasonic waves in the standard sample, the calculated parameters: the radius of the sample - 55 mm, the speed of propagation of transverse waves in the material sample - 3.26 mm / s.
APPENDIX 4 (recommended). SAMPLE CO-4 for wavelength measurements and the ultrasonic wave frequency converters ANNEX 4 Recommended
1 -
slots; 2 - line, 3 - converter; 4 - the block of steel grade 20 to GOST 1050 or steel 3
to GOST14637; the difference in depth of grooves on the ends of the sample sample
(); width of
()
Standard sample SB-4 is used for measuring the wavelength (frequency) of the excitation transducer to the angles The wavelength
I of 40 to 65 ° C and a frequency of 1.25 MHz to 5.00.
(frequency) is determined by the interference method based on the
averagedistances between the four nearest to the center of the sample extremes of the amplitude of the echo signal from the parallel grooves with a smoothly varying depth.
. where
- the angle between the reflective surfaces of slots equal (see. Drawing) .
The frequency
is determined by the formula
.
wherein
- the propagation velocity of the transverse waves in the material of the sample in m
/ s.
Annex 5 (informative). DEPENDENCE N = f (epsilon) for steel, aluminum and its alloys, titanium and its alloys ANNEX 5 Reference
Dependence
for steel, aluminum and its alloys, titanium and its alloys
ANNEX 6 METHOD FOR DETERMINING SENSITIVITY LIMIT flaw detection and equivalent area of detected defects on samples with a cylindrical bore APPENDIX 6
Limiting sensitivity area
in square millimeters flaw transducer with an inclined (or equivalent
detected defect) is determined by the company standard model with a cylindrical bore
or standard sample SB-2A or CO 2 in accordance with the expression
. wherein
- the indication of the attenuator, an attenuation of the echo signal from the side of
the cylindrical hole in the company standard sample or standard sample SB-2A, or CO 2 to a level at which the estimated ultimate sensitivity in dB;
- The indication of the attenuator, where the estimated ultimate sensitivity of
flaw, or
where the amplitude of the echo signal from the test defect reaches a level at which the estimated ultimate sensitivity in dB; - The difference between the coefficients of transparency border prism converter - metal compounds, and controlled coefficient of transparency of the boundary of the prism converter metal standard sample of businesses or standard sample SB-2A (or CO 2) dB
(0).
By standardizing sensitivity company standard model having the shape and smoothness of the same, as well as controlled compound
= 0;
- The radius of the cylindrical hole, mm;
- The speed of the transverse waves in the material sample and controlled compounds, m / s; - Frequency ultrasound MHz;
- The middle path in the prism of the ultrasound transducer, mm;
- The speed of the longitudinal wave in the material of the prism, m / s; and
- the angle of the ultrasound beam entering into the metal and the angle of the prism
converter respectively, hail; - The depth to which the estimated ultimate sensitivity, or on which the detected defect, mm;
- The depth of the cylindrical hole in the sample, mm;
- Damping coefficient of the transverse wave in the metal compound and the controlled specimen,
mm.
To simplify the determination of the maximum sensitivity and the equivalent area is recommended to calculate and construct a diagram (SKH-chart), linking the limiting sensitivity
(equivalent
() and the depth
area), conditional factor
detection defect
to which the estimated (adjustable) limit sensitivity, or on which the
detected defect . The convergence of the theoretical and experimental values 20%.
at
= (50 ± 5) ° no worse than
An example of the construction of SKH-chart and determine the ultimate sensitivity and equivalent area
EXAMPLES Control joints butt joints of sheets of 50 mm thick mild steel is performed by tilting the transducer with known
parameters:,,. The frequency of the ultrasonic vibrations generated by
the transducer is in the range of 26.5 MHz ± 10%. The attenuation coefficient = 0.001 mm.
When measured according to the standard sample SB-2 revealed that calculated for the set of conditions and shown in FIG.
= 3 mm
= 50 °. SKH-diagram
= 44 mm using the formula above is
Example 1. Measurement, the
= 2.5 MHz. Calibration is carried out on the standard model of the
enterprise with a cylindrical bore 6 mm in diameter, located at a depth
= 44 mm; shape and
surface finish of the sample corresponds to the shape and surface finish of controlled compounds. Display attenuator corresponding to the maximum attenuation which still audible indicator registers the echo signal from the cylindrical hole of the sample is
= 38 dB.
It is required to determine the ultimate sensitivity for a given flaw setting ( and the search for defects at a depth of
= 38 dB)
30 mm.
The desired value of maximum sensitivity SKH-chart corresponds to the point of intersection of the ordinate
= 30 mm with a line
and is
You want to adjust the marginal flaw sensitivity defects
= 65 mm,
Setpoints
and
Then
= 7 mm
5
mm.
for the desired depth of the
= 38 dB.
on SKH-diagram corresponds
dB.
= -9 + 38 = 29 dB.
Example 2.
Measurement, the
= 2.2 MHz. The adjustment is made on the standard model of CO 2
(=44 mm). By correlating echo amplitudes of identical cylindrical holes in sheets controllable compound in the standard sample SB-2 revealed that
= -6 dB.
Display attenuator corresponding to the maximum attenuation which still audible indicator fixed echoes of the cylindrical hole in the CO 2 is
= 43 dB.
Required to determine the equivalent area of the defect detected. In accordance with the measurements of the depth of the defect
= 50 mm, and the reading of the attenuator,
wherein the further fixed echo from the defect
= 37 dB.
The required value of the equivalent area
of the defect detected on SKH-chart corresponds
to the point of intersection of the ordinate
= 50 mm with a line
(43-6) = 0 dB and is
14
mm.
= 37-
ANNEX 7 (recommended). METHOD FOR DETERMINING THE MAXIMUM scanning step ANNEX 7 Recommended
Step
scanning cross-longitudinal movement of the transducer with the parameters of
15 mm
= 15 mm MHz determined by the nomogram shown in the figure
(- a way of
sounding).
1
-
= 65 °;
= 20 mm and a 30 mm 4 -
= 50 °;
= 30 mm 2 -
= 50 °, = 50 mm; 5 -
= 50 °; = 40 mm 3 -
= 65 °, =
= 50 °, = 60 mm
Examples:
1. Set
2. Set
= 6 dB,
= 50 °,
= 0,
= 40 mm
= 50 °. On the nomogram
=1
= 3 mm.
= 4 mm. On the nomogram
2 dB.
Step scanning longitudinal and transverse movement of the transducer is determined by the
formula
or * where - 1, 2, 3, etc. - Number of steps; * - The distance from the exit point to the scanned cross-section normal to the contact surface of the object under control. _______________ * Formula and explication of it matches the original. - Note manufacturer's database. The parameter
is determined experimentally for a cylindrical hole in the sample CO 2 or CO-
2A, or the standard model of the enterprise. For this measure the notional width of the cylindrical hole distance
by loosening the maximum amplitude equal
and minimum
from the projection of the center of the reflector on the working surface of the
sample to the point input transducer located at a position at which the conditional width. Meaning
is calculated by the formula
.
which
- given the distance from the emitter to the exit point of the beam in the
transmitter.
ANNEX 8 (mandatory). CLASSIFICATION defective butt welds for ultrasonic CONTROL ANNEX 8 Required 1. This annex applies to butt welds of pipelines and building structures and establishes a classification of defects in butt welds metals and their alloys 4 mm or more on the results of ultrasonic testing. The application is a unified standard section of the USSR and the GDR standard for the following main features: designation and name of weld defects; classification of defects to one type; establishing steps the size of defects;
establishing levels of frequency of defects; the establishment of the length of the assessment area; setting a class of defects depending on the type of defect, size and stage of speed steps defects. 2. The basic measured characteristics of the detected defects are: the diameter of the
equivalent disc reflector;
the coordinates of the defect
() in the section (chert.1);
conditional size of the defect (see. chert.1); the ratio of the amplitudes of the echo signal echo
reflected from the detected defect and the
signal, which has undergone specular reflection from the inner surface (chert.2);
the angle of
rotation of the transducer between the extreme positions at which the maximum
amplitude of the echo signal from the edge of the defect detected is halved with respect to the maximum amplitude of the echo signal at the location of the transducer perpendicular to the axis of the joint (chert.3).
Chert.1
Chert.2
Chert.3
Characteristics used to assess the quality of specific weld procedures and the accuracy of the measurements must be installed in the technical documentation for control. 3. The diameter of the
equivalent disc reflector is determined using diagrams or standard
(test) samples of the maximum amplitude of the echo signal from the detected defect. 4. Conventional dimension of the defect is identified (see. Chert.1): notional
length;
conditional
width;
conditional height 5. conditional length
. in millimeters measured along the length of the area between the
extreme positions of the transducer is moved along the seam oriented perpendicular to the axis of the seam. Conditional width
in millimeters is measured along the length of the area between the
extreme positions of the transducer being moved perpendicular to the seam. Conditional height
in millimeters (or in microseconds) is measured as the difference
between the values of depths
(,)
the location of the defect in the extreme positions of
the transducer being moved perpendicular to the seam. The extreme positions of the transducer are those in which the amplitude of the echo signal from the detected defect is reduced to a level of a predetermined portion of the maximum value and the set of technical documentation for the control, duly approved.
Conditional width
and height of a conditional
defect is measured in the joint section
where the echo from the defect has the largest amplitude at the same position of the transducer. 6. As a result of ultrasonic testing of the defects are assigned to one of the types: volume unextended; extended volume; junction. 7. To determine the accessories to one of the defect types (Table 1) are used: Comparison conditional length of values of the conditional extension of
the detected defect with the calculated and measured omnidirectional reflector at the same depth as the
detected defect;
Table 1 The types of defects Volume unextended
Signs ; Or
, Or;
Volumetric extended
; Or, or;
Planar or, or
comparing the amplitudes of the echo signal reflected from the defect detected neighbor back to the seam converter
(), with the amplitude of the echo signal
() which has undergone
specular reflection from the inner surface (see. chert.2); comparing the size of the contingent detected defect non-directional
with the size of the contingent
reflector;
comparing the angle
between the extreme positions of the transducer, the corresponding
reduction of the maximum amplitude of the echo signal from the edge of the defect with the value
set on the control of technical documentation.
8. Depending on the ratio of the equivalent diameter of the of
twice,
detected defect to the thickness
the base metal are four stages of defect size, which is determined by chert.4.
Chert.4 9. Depending on the ratio of the total length of defects
in the evaluation section to the length
of the assessment area are four stages of frequency of defects, which are determined by chert.5.
Chert.5 The total length of the defect is calculated for each type separately; while for volume and extended planar summarize their notional length unextended equivalent
and volume to summarize their
diameters.
10. The length of the assessment area is determined depending on the thickness of the base metal.With
10 mm evaluation portion shall be equal to
10, but not more than 300 mm,
10 mm - equal to 100 mm. The choice of the site on the weld produced in accordance with the technical documentation for the control, duly approved.
If the length of the controlled weld is smaller than the calculated estimated length portion, the length for evaluation section taken weld length. 11. Proven parts of the joints, depending on the type of defects, their location in the cross section, the size of the defect level (first figure) and step frequency of defects (the second number) are assigned to one of five classes according to Table 2.
Table 2 Type of defect Volume unextended
Volume extensive subsurface and outcropping
Class
The step size of the defect and the level of frequency of
defects
defects
1
eleven
2
12; 21
3
13; 22; 31
4
23; 32
5
14; 24; 33; 41; 42; 43; 44
1
-
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