GOST R 53205-2008
GOST R 53205−2008 nondestructive testing. Determination of grain size of steel by the acoustic method. General requirements
GOST R 53205−2008
Group Т59
NATIONAL STANDARD OF THE RUSSIAN FEDERATION
Nondestructive testing
DETERMINATION OF GRAIN SIZE STEEL ACOUSTIC METHOD
General requirements
Non-destructive testing. Evaluation of size grains of steel by acoustic method. General requirements
OKS 77.040.10
Date of introduction 2010−01−01
Preface
The objectives and principles of standardization in the Russian Federation established by the Federal law of 27 December 2002 N 184-FZ «On technical regulation», and rules for the application of national standards of the Russian Federation — GOST R 1.0−2004"Standardization in the Russian Federation. The main provisions"
Data on standard
1 DEVELOPED by Autonomous non-commercial organization «Scientific-research center of control and diagnostics of technical systems» (ANO «nits KD»)
2 SUBMITTED by the Technical Committee for standardization TC 132 «Technical diagnostics"
3 APPROVED AND put INTO EFFECT by the Federal Agency for technical regulation and Metrology dated December 25, 2008 No. 693-St
4 INTRODUCED FOR THE FIRST TIME
Information about the changes to this standard is published in the annually issued reference index «National standards», and the text changes and amendments — in monthly indexes published information «National standards». In case of revision (replacement) or cancellation of this standard a notification will be published in a monthly information index «National standards». Relevant information, notification and lyrics are also posted in the information system of General use — on the official website of the Federal Agency for technical regulation and Metrology on the Internet
Introduction
The grain size refers to the number of the most important structural characteristics of the steels that determine their performance characteristics.
Currently used metallographic method for the determination of grain size, being quite time consuming, primarily for control samples and not very applicable for finished products.
In recent years, actively developed equipment and methods of nondestructive acoustic control, aimed at their application to determine the parameters of the structure and physico-mechanical characteristics of steels. The fact of the dependence of ultrasound attenuation coefficient from the value of the grain size of the steel is securely installed* and is increasingly being used in engineering practice [1].
________________
* Himchenko N. In. Relative ultrasonic method of structural analysis of metals. — M., Containertypes, 1964, 68 p
This standard is designed to provide a methodological basis for the application of the acoustic method for the rapid determination of grain size of steel as samples, and finished subassemblies.
1 Scope
This standard applies to acoustic echo method for determining the grain size of steel for specimens and structural elements, having two plane-parallel surfaces in the measuring area.
This standard specifies the basic requirements for the procedure of determining the grain size of steel, averaged over the material thickness and area of the ultrasonic beam, using bulk ultrasonic waves propagating through the thickness of the sample material or subassembly. Set a real standard for the acoustic method can be applied both in laboratory studies and in real conditions of operation of technical objects for various purposes.
2 Normative references
This standard uses the regulatory references to the following standards:
GOST 12.1.001−89 System safety standards. Ultrasound. General safety requirements
GOST 12.1.004−91 System safety standards. Fire safety. General requirements
GOST 12.1.005−88 standards System of labor safety. General hygiene requirements for working zone air
GOST 12.1.019−79 System of standards of occupational safety. Electrical safety. General requirements and nomenclature of types of protection
GOST 12.1.038−82 standards System of labor safety. Electrical safety. The maximum permissible values of the touch voltage and currents
GOST 12.2.003−91 System safety standards. Equipment production. General safety requirements
GOST
GOST 12.3.002−75 System safety standards. The process of production. General safety requirements
GOST 32−74 Oil turbine. Specifications
GOST 2768−84 Acetone. Specifications
GOST 2789−73 surface Roughness. Parameters and characteristics
GOST 5639−82 of Steel and alloys. Methods of detection and determination of grain size
GOST 6259−75 Reagents. Glycerin. Specifications
GOST 17299−78 ethyl Alcohol technical. Specifications
GOST 26266−90 nondestructive testing. The ultrasonic transducers. General technical requirements.
Note — When using this standard appropriate to test the effect of reference standards in the information system of General use — on the official website of the Federal Agency for technical regulation and Metrology on the Internet or published annually by the information sign «National standards» published as on January 1 of the current year and related information published monthly indexes published in the current year. If the reference standard is replaced (changed), when using this standard should be guided by replacing (amended) standard. If the reference standard is cancelled without replacement, then the situation in which the given link applies to the extent that does not affect this link.
3 Symbols and abbreviations
3.1 this standard applies the following designations:number of grain according to GOST 5639;
— average grain diameter, mm;
— the speed of propagation of longitudinal elastic waves, m/s;
— the minimum value of the nominal frequency of the transducer used;
— the maximum value of the nominal frequency of the transducer used;
— the number of nominal frequency of the transducer used;
— the nominal frequency of the used piezoelectric transducers MHz;
— amplitude signals at a given amplification factor and frequency
;
structural coefficients, calculated by the formula
structural coefficients of standard samples.
3.2 this standard applies the following abbreviations:
PEP — piezoelectric Converter;
OK — the object of control;
C. measuring instruments;
SOP — standard sample of the enterprise.
4 General provisions
4.1 the principle of the acoustic method for the determination of the grain size of the steel is based on the existing relationship between the attenuation coefficient of ultrasonic waves and the size of the average grain size of steel.
4.2 the influence of the average size of grain size of steel on frequency dependence of ultrasound attenuation coefficient allows the use of a relatively simple methodology of acoustic measurements, providing the possibility of rapid measurements of the average grain size of steel in the range of 1 to 8 according to GOST 5639 accuracy up to units.
4.3 Regulated by the standard acoustic method for determining the grain size of the steel is based on the manual method of ultrasonic pulse-echo contact testing with the use of combined or separate-combined piezoelectric converters according to GOST 26266.
4.4 the Optimal form of the emitted signal is a pulse with high frequency (ultrasonic) filling the envelope smooth and effective duration (at the level of 0.6 of the maximum amplitude) 2−4 period of high-frequency filling.
4.5 determine the size of the grains of steel are the volume average of the ultrasonic beam, determined by the transverse dimensions of the probe and the thickness of the material OK.
5 safety Requirements of the work
5.1 measurements and processing of their results allow operators with skills in the operation of equipment of ultrasonic nondestructive testing, able to use national and industry normative and technical documents on the acoustic control techniques, trained to work with used C and are certified for knowledge of safety regulations in the relevant sector of industry.
5.2 During the work of determination of average grain size steel acoustic method the operator should be guided by GOST 12.1.001, GOST 12.2.003, GOST 12.3.002 and rules of technical safety for operation of electrical installations churchyard 12.1.019 and GOST
5.3 Work is performed in accordance with the safety requirements set out in the instruction manual of equipment, part of the used SI.
5.4 General hygiene requirements for working zone air — according to GOST
5.5 In the organization of work on determination of average grain size of steels by the acoustic method must be met fire safety requirements according to GOST
6 Requirements for measuring instruments
6.1 as SI apply collected from production equipment, or specialized devices for measuring the grain size of the steel (hereinafter — the devices) are certified and verified in the prescribed manner.
6.2 Operational characteristics of the used ultrasound devices must fully comply with the requirements of technical specifications, technical requirements, passports and of this standard.
6.3 For tuning ultrasonic devices use a special industry-standard or standard samples of grain size of the manufacturer. Each SOP must be certified and have the appropriate certificate of attestation and passport. SOPS should undergo periodic regular and in special cases, extraordinary attestation (Ministerial practice) in the prescribed industry order.
6.4 When using the dual probe transducers should meet the requirements shown below.
6.4.1 the distance between the exit points of the ultrasonic beam-emitting probe and the exit (entrance) of the host ultrasound probe must correspond to a single reflection from the inner surface of the test object.
6.4.2 the angles of the prisms, the probe must be such that when falling of the ultrasonic beam on the inner surface of the test object was missing the transformation of wave types upon reflection.
6.5 SI should contain the set of probes, providing radiation and reception of longitudinal elastic waves in the frequency range from to
.
6.5.1 For the investigated steel on the basis of the analysis of relevant technical documents establish the highest possible value of the average diameter of the grain .
6.5.2 Values ,
calculated by the formulas:
6.5.3 the Minimum value must be equal to 5. For this purpose the frequency range from
to
is divided into octave bands, the boundaries of which should correspond to the nominal frequencies of the used probes:
Note — To reduce the errors of determination of average grain size may be increased to a value through the use of additional nominal frequencies that are within the selected octave bands.
6.6 Auxiliary devices and materials
6.6.1 Grinding tool for surface preparation according to GOST
6.6.2 Degreasing liquid (alcohol according to GOST 17299 or acetone GOST 2768) for surface preparation.
6.6.3 couplant, which use a special fluid is thick enough for good ultrasound conducting fluid (e.g., glycerin according to GOST 6259, autoly 6, 10, 18, compressor and other related oil according to GOST 32 having wetting properties with respect to the surface controlled metal and the contact surface of the ultrasonic transducer used).
7 requirements of the test object
7.1 Minimum material thickness OK at the measurement points should provide the possibility of obtaining on the screen of the monitor device of the ultrasound device reflected signal at the minimum frequency .
7.2 Maximum material thickness OK at the measurement points should provide the possibility of obtaining on the screen of the monitor device of the ultrasound device reflected signal at maximum frequency .
7.3 the Temperature of the surface OK on the measuring points: 0 °C-80 °C.
7.4 Before installing the probe surface is cleaned of dirt, scale, rust and degreased.
7.5 surface Roughness at the point of measurement must be not more than 2,5 according to GOST 2789.
7.6 in the presence of the weld distance from the measuring point to the weld should be at least twice the thickness of the OK in the measurement area.
8 preparation for measurement
8.1 Study certificates for the material is OK.
8.2 Determine the location of points of measurements and select the measurements of grain size.
8.3 the state of the surface at selected points in accordance with the conditions of measurement (see 7.3−7.5).
8.4 the Dimensions of the prepared surface should be three times greater than the corresponding dimensions of the contact surface probes.
8.5 put a layer of contact liquid on the prepared surface OK.
8.7 turn on the device, check its performance when displaying video device timebase of the received signals.
8.8 Check on the time scan of additional pulses caused by the presence in the field of measurement for more reflective surfaces (faults, layers).
9 Order of measurements
9.1 transfer device in the operating frequency , is connected to the instrument probe with a nominal frequency
and set it to the surface OK at the selected point of control.
9.2 Using adjusting the amplitude of the probe pulse, to achieve the amplitude of the reflected signal corresponding to the value of 0.5−0.7 of the vertical screen size of the video monitoring device. The obtained value of the amplitude of the signal is taken for the value .
9.3 without changing the adjustment of the amplitude of the probe pulse, take measurements of the amplitudes of the reflected signal for all nominal frequencies
in the selected control point.
10 Rules for processing results of measurements
10.1 On the basis of measurement results obtained in accordance with 9.2−9.3, calculate the values of the structural coefficients .
10.2 Build the schedule of dependence in accordance with figure 1.
Figure 1 — Graph of K (i) of i
Figure 1 — Graph of
10.3 the resulting curve is compared with the series of curves of the dependence 
10.4 From the calibration curves 
.
10.5 as the number of grains according to GOST 5639 tested OK in the measurement area taking the number corresponding calibration curve
.
Note — an Example of a specific use, regulated by the standard method given in Appendix A.
11 Rules of registration of results of measurements
11.1 the results of the control record in the journal, the form of which is given in Appendix B.
Additional information to be logged, the order of registration and storage of the journal, or conclusions should be set in the technical documents for the control.
11.2 If the measurement of grain size are part of the research work, the results of measurements issued in accordance with the General requirements and rules of registration of reports on research work.
11.3 the results of the retain control until the next control OK.
Annex a (informative). An example of determining the grain size of the steels by the acoustic method
Appendix A
(reference)
A. 1 as OK use a pipe made of austenitic steel 12KH18N10T.
A. 2 Pre-conducted the experimental study of the influence of grain size of steel by the amount of attenuation of ultrasound.
A. 3 In accordance with 6.5 was chosen frequency range is appropriate for control: =0,7 MHz;
=11,2 MHz.
A. 4 the frequency Range from before
was divided into a 4-octave band.
A. 5 the Nominal frequency of used transducer was equal to: =0,7 MHz;
=1.4 MHz;
=2.8 MHz;
=5.6 MHz;
=11,2 MHz.
A. 6 In accordance with section 9 were carried out the necessary acoustic measurements on standard samples with the number of grain according to GOST 5639 from 1 to 8.
A. 7 Structural coefficients of standard samples 
A. 8 the measurement Results are shown in table A. 1.
Table A. 1 — Results of measurements on standard samples
| The number of grain | The values of the structural coefficients | |||
| 8 | Of 1.00 | Of 1.00 |
Of 1.00 | 0,85 |
| 7 | Of 1.00 | Of 1.00 |
Of 1.00 | 0,47 |
| 6 | Of 1.00 | Of 1.00 |
Of 1.00 | 0,13 |
| 5 | Of 1.00 | Of 1.00 |
0,63 | 0 |
| 4 | Of 1.00 | 0,87 |
0 | 0 |
| 3 | Of 1.00 | 0,69 |
0 | 0 |
| 2 | Of 1.00 | 0,25 |
0 | 0 |
| 1 | 0,69 | 0 |
0 | 0 |
A. 9 figure A. 1 shows a series of calibration curves corresponding to table A. 1. Curve number corresponds to the number of grains of the corresponding standard sample.
Figure A. 1 — Series of calibration curves of the structural coefficients
Figure A. 1 — Series calibration curves
10 A. In the area of control on the pipe surface has been prepared, the point for measurement in accordance with the requirements of 8.3−8.8.
A. 11 was measured in accordance with the requirements of 9.1 to 9.3. The measurement results are shown in table A. 2.
Table A. 2 — Results of measurements on the segment of the pipeline from steel 12KH18N10T
| The values of the structural coefficients | |||
| Of 1.00 | 0,90 |
0,10 | 0 |
12 A. the Curve plotted on a series of calibration curves shown in figure A. 2 (thick line 100).
Figure A. 2 — Curve according To (i) of i is applied to a series of calibration curves
Figure A. 2 — Curve applied to a series of calibration curves
13 A. From figure A. 2 it follows that the number of grains in the point of control closest to 4.
Appendix B (recommended). Form of measurement Protocol
Appendix B
(recommended)
| «CLAIM" | ||
| Head | ||
| name of the organization | ||
| personal signature | initials, surname | |
«_____" ___________ 20 __ G. | ||
| PROTOCOL measurement of average grain size | |||||||||||
| (object of control, controlled area OK) | |||||||||||
| 1 measurement date | |||||||||||
| 2 organization conducting the measurement | |||||||||||
| 3 the owner of the object | |||||||||||
| 4 information about the object control: | |||||||||||
| appointment | |||||||||||
| the manufacturer, manufacturing technology OK | |||||||||||
| the treatment | |||||||||||
| thickness OK in the measurement area | |||||||||||
| surface condition | |||||||||||
| for more information about the test object | |||||||||||
| 5 Sketch of the test object showing the location of measurement points and their numbering (in the app) | |||||||||||
| 7 Information about the content of the object of control | |||||||||||
| country of origin | |||||||||||
| material grade (national, different standard) | |||||||||||
| manufacturing technology | |||||||||||
8 the Number of nominal frequency of the transducer used | |||||||||||
| 9 the Nominal frequency of the transducer used (MHz) |
Table 1 — Values of the structural coefficients
| … |
| The number of grain according to GOST 5639−82 |
| The research done by the operator: | |||
| personal signature |
initials, surname | ||
| Head of laboratory NDT: | |||
| personal signature | initials, surname | ||
Bibliography
| [1] RD 153−34.1−17.404−2000 | Ultrasonic testing of the grain size in the superheating pipes from steel 12Х18Н12Т thermal power plants |
