GOST 22727-88
GOST 22727−88 the rolled sheet. Methods of ultrasonic testing
GOST 22727−88
Group B09
STATE STANDARD OF THE USSR
THE ROLLED SHEET
Methods of ultrasonic testing
Rolled sheet.
Ultrasonic test methods
AXTU 0909
Valid from 01.07.89
to 01.07.94*
_____________________
* Expiration removed
Protocol N 3−93 Interstate Council
for standardization, Metrology and certification.
(IUS N 5−6, 1993). — Note the CODE.
INFORMATION DATA
1. DEVELOPED AND INTRODUCED by the Ministry of ferrous metallurgy of the USSR
PERFORMERS
Tursunov D. A., Cand. Fiz.-Mat. Sciences; A. S. Golubev, PhD. tech. Sciences; B. A. Kruglov, PhD. Fiz.-Mat. Sciences; V. N. Potapov, PhD. tech. D. (leader); Verevkin M. V., Cand. tech. Sciences; D. F. Kravchenko, Cand. tech. Sciences; G. N. Trofimov, V. A. Fedorov, V. Zaitsev, V. A. Kashirin, I. M. Barynina, V. A. Prikhodko
2. APPROVED AND put INTO EFFECT by Decision of the USSR State Committee for standards from
3. REPLACE GOST 22727−77
4. The term of the first verification second quarter of 1994.
The frequency of inspection — 5 years
5. REFERENCE NORMATIVE AND TECHNICAL DOCUMENTS
| The designation of the reference document referenced |
The number of the paragraph, subparagraph, enumeration, applications |
| GOST 8.315−77 |
Annex 1 |
| GOST 12.1.001−83 |
5.2 |
| GOST 12.1.003−83 |
5.4 |
| GOST 12.1.004−85 |
5.5 |
| GOST 12.2.003−74 |
5.2 |
| GOST 12.2.002−81 | 5.2 |
| GOST 14782−86 | 2.4; Appendix 2 |
| GOST 15895−77 |
Annex 1 |
| GOST 20415−82 |
3.1; 5.1 |
| GOST 23049−84 |
Sec. 1 |
| GOST 23829−85 |
Annex 1 |
| GOST 24555−81 |
2.3 |
This standard specifies: echo-method, shadow, echo-through-and repeatedly-shadow in combination with the shadow, the echo method in combination with a mirror-shadow methods of ultrasonic testing of rolled sheets from carbon and alloyed steels, including dual-layer, with a thickness of 0.5 to 200 mm, used for detecting metal discontinuities such as delaminations, clusters of non-metallic inclusions, sunsets, peeling a plating layer, and the determination of their conditional or equivalent sizes.
The standard does not specify the methods of ultrasonic inspection for recognition of types, orientations, and other valid characteristics of defects.
The need for ultrasonic control method and control volume point in the normative-technical documentation for hire.
Terms used in this standard, and their explanations are given in Appendix 1.
Characteristics of methods of ultrasonic testing are given in Appendix 2.
1. EQUIPMENT
Ultrasonic flaw detectors, corresponding to the parameters and technical requirements GOST 23049−84 types UZDON and USDS, equipped with piezoelectric or electromagnetic acoustic transducers, and other means of ultrasonic testing, certified in the prescribed manner.
Control samples in accordance with Annex 3.
DGS diagrams.
Assistive devices for compliance with the parameters of scan and determine characteristics of the identified discontinuities.
2. PREPARATION FOR CONTROL
2.1. Preparation control is performed in the following sequence:
estimate visually the surface condition of the rental;
check the functioning of the means of mechanization and automation;
validate the setting of the sensitivity control.
2.2. The surface of sheet metal, which moves the transducer cleaned of dirt, loose scale, captured and spatter.
In case of impossibility of realization of a given testing sensitivity due to poor surface quality of sheet metal, carried out additional surface treatment (shot blasting, abrasive, chemical, etc.).
3. CONTROL
3.1. Monitoring is carried out according to the technical documentation developed in accordance with GOST 20415−82.
3.2. When control sheet is scanning one or more transducers. The scanning parameters indicated in the technical documentation for the control.
When moving the transducer manually, and to determine the characteristics of the identified discontinuities are allowed to use equipment without auxiliary devices intended for compliance with the scan settings.
3.3. In the control echo and echo-through methods in a given time interval to register one or more echo pulses from discontinuities, the amplitude of at least one of which is equal to or exceeds the level of preset sensitivity.
3.4. When you control the shadow, or many times-the shadow register method of decreasing the amplitude of the first or th passing through the sheet pulse to or below the level corresponding to a predetermined sensitivity.
3.5. In the control mirror-shadow method recorded a decrease in the amplitude of the bottom signal to or below a level corresponding to a given sensitivity.
4. ASSESSMENT AND REGISTRATION OF TESTING RESULTS
4.1. The main monitored characteristics of the continuity of the sheet metal:
the control sensitivity determined by the registration parameters of sensitivity according to table. 2 of Annex 2;
conditional square of discontinuities: the minimum considered (cm
); maximum (
cm
);
conditional area the maximum area of discontinuities (m
);
conditional relative area (percent), defined by the proportion of area occupied by discontinuities of all types (
,
, and
), in any square area of the surface unit of sheet metal with an area of 1 m
; or proportion of area occupied by discontinuities of all types in the entire area of a unit of sheet metal;
the maximum allowable conventional length of discontinuities (mm).
If the width of the controlled rolled plates less than 1,000 mm, it is square footage when determining the relative conditional area, take a rectangular plot with an area of 1 mwith the lower side equal to the width of the rental.
Two sides of a square or rectangular plot should be parallel to the side edge of the sheet p
the rokat.
4.2. Continuity of sheet metal, steel, smelted in a vacuum arc, induction furnaces or the use of special remelting (ESR, var, etc.) for their echo method while manual scanning can (by agreement between manufacturer and consumer) to characterize the results of the control:
consider the minimum equivalent size , mm, discontinuities;
maximum permissible equivalent size , mm, discontinuities;
the number of unextended discontinuities with equivalent size from
to
allowed on the whole area of units of sheet metal or parts.
The figures indicate continuity in the normative and technical documentation for specific products, the values and
choose from a number of 2,0; 2,5; 3,0; 5,0; 6,0; 8,0 mm
.
4.3. It is allowed to introduce additional performance indicators, for example, the minimum distance between the conventional boundaries of single discontinuities number of discontinuities in the entire area of a unit of sheet metal or parts, etc., which should be stipulated in the normative-technical documentation for specific products.
4.4. Indicators of continuity and sensitivity in the control of sheet metal, a normal or multiply-reflected shear waves determined by agreement between manufacturer and consumer and report of normative-technical documentation for specific products.
4.5. Defect, located in one or more planes through the thickness of sheet metal, are combined in one inconsistent if the distance between their conventional boundaries less than the specified regulatory and technical documentation for specific products and in the absence of guidance in the normative-technical documentation, — if it is less than 30 mm.
With automatic control units, providing a continuous surface scan of sheet metal for the conventional area of discontinuity flaws of metal take the actual area of the relevant entries in the defects recording obtained for a given sensitivity control. The conditional area of the United discontinuities equal to the sum of their consider the conditional space.
4.6. Under the control of a double-layered sheet metal defect, located in the metal core layer, cladding layer, in the area of the connection layers, consider layers or only in the area of the connection layers.
4.7. Clusters of discontinuities, each of which has a conditional area less than that recorded at distances between 30 mm and less, unite in the area of discontinuities. The conditional area of the discontinuities
is equal to the square of the units of sheet metal within the circuit, covering all of its discontinuities.
4.8. Upon detection of discontinuities, adjacent to side and end to uncontrolled areas of sheet metal, their boundaries extend to the edges.
4.9. The continuity of the sheet metal, depending on the values of the indicators of the continuity of the estimated classes.
4.10. Indicators of continuity of HRP in classes 01; 0; 1; 2; 3 in the control methods with the characteristics with the legend А24Э, D3Э, А16Э, D5Э, А8Э, D8Э, А12Т, А14Т, А16Т and А24ЭС+А20Т, А16ЭС+А20Т, А8МТ2+А20Т given in Appendix 4.
Classes and their respective indicators indicative of the continuity in the normative and technical documentation for metal products.
When specified in the normative-technical documentation of the class, the assessment of continuity is carried out on indicators ,
,
,
.
4.11. Allowed for different sections of the rental to establish requirements for continuity in different classes.
4.12. Indicators of continuity of rolled products and plate in the control methods of characteristics not specified in clause 4.10, are installed in the normative-technical documentation for specific types of steel products.
4.13. Defect fixed in defectogram, records or control logs.
4.14. In defectogram, records or control logs indicate the cipher normative-technical documentation for metal products, the characteristic of the controlled object, the value of the indicators of continuity, the name or index of the operator who carried out the monitoring, control parameters.
5. SAFETY REQUIREMENTS
5.1. For ultrasonic testing of sheet metal allowed the radiographers have successfully passed the exams in accordance with GOST 20415−82.
5.2. When carrying out ultrasonic testing of sheet metal the operator should be guided by GOST 12.1.001−83, GOST 12.2.003−74, GOST 12.2.002−81, rules of technical operation of electrical installations and safety rules for electrical installations.
5.3. When performing control, the requirements of «Sanitary norms and rules when working with equipment that generates the ultrasound transmitted by contact to the hands working» N 2282−80 approved by the USSR Ministry of public health and safety requirements set out in the technical documentation for applicable equipment.
5.4. Noise levels in the workplace inspector must not exceed dopustimykh 12.1.003−83.
5.5. At the organization of works on control must be complied with fire safety requirements specified in GOST 12.1.004−85.
ANNEX 1 (reference)
ANNEX 1
Reference
Table 1
| The term |
Explanations |
| An inconsistent | The heterogeneity of the metal causes reflection or attenuation of ultrasonic waves sufficient for recording in the control with the specified sensitivity |
| Echo-method | According to GOST 23829−85 |
| The shadow method | According to GOST 23829−85 |
| Echo-through method | The method is to measure and register the amplitude reflected from a defect of the metal of the ultrasonic pulses, and the emission of ultrasonic pulses produced by one of the surfaces of the controlled rolled plates, and the acceptance from the opposite surface. Usually the registration is done on the value of the ratio of the amplitude of the echo pulses from defect to the amplitude of the first transmitted through the sheet metal of the impulse caused by the same probing pulse |
| Many times-the shadow method | The method is to measure and register the amplitude of the |
| Measurement of the amplitude of the signal can be carried out either in absolute terms or relative to the amplitude of the first transmitted through the sheet steel pulse | |
| Mirror-shadow method | According to GOST 23829−85 |
| Dead zone | According to GOST 23829−85 |
| Uncontrolled zone | According to GOST 23829−85 |
| The sample size | According to GOST 15895−77 |
| Standard sample | GOST 8.315−78 |
| The DGS / AVG diagram | According to GOST 23829−85 |
| Scan | According to GOST 23829−85 |
| Continuous scanning | Process control, in which between adjacent probing pulses and the neighboring trajectories of the point that there is no uncontrolled areas |
| Selectable linear scanning | Process control, in which between adjacent probing pulses are not, and between neighboring trajectories of input points are uncontrolled areas |
| A probe pulse | According to GOST 23829−85 |
| The conditional border | The locus of the provisions of the center of the transducer to rolled sheet metal in which the amplitude of the detected signal reaches a value corresponding to a predetermined sensitivity or defects recording — the outline of the image defect |
| Conventional size | The maximum distance (in this direction) between two points located on the border of the conditional defect |
| Conditional area | Square footage of sheet metal, a limited conventional border defect |
| Unextended the inconsistent | An inconsistent metal, the largest conventional size of which does not exceed the relative size of the flat-bottomed reflector diameter |
| Equivalent to the size of the unextended defect |
The diameter of the flat bottom of the reflector, the echo signal which is equal to the echo signal from the considered defect, located at the same depth |
| Extended defect |
All the discontinuities of the metal, which can not be attributed to the unextended |
| Area of discontinuities | The accumulation of discontinuities, each of which is conditional on the size (area) is less considered in control, if the distance between them is not more than 30 mm |
| The defects recording | Large image units of sheet metal, which can be used to determine the location and conditional dimensions of the detected discontinuities |
| Point of entry | According to GOST 23829−85 |
| Control defect | According to GOST 23829−85 |
, unextended discontinuities include such an inconsistent metal, the largest conventional size of which does not exceed the relative size of the flat-bottomed reflector diameter ANNEX 2 (mandatory). CHARACTERISTICS OF METHODS OF ULTRASONIC TESTING
ANNEX 2
Mandatory
1. The main characteristics of the control methods are:
the method for setting sensitivity;
method sensitivity settings;
registration settings sensitivity;
maximum deviations of registration parameters sensitivity.
2. When you set the sensitivity setting for the beginning of a take amplitude:
first bottom of the first or the last signal on sections of sheet metal that does not contain discontinuities, in the control by longitudinal and transverse waves by all methods, except for the echo-through; echo-through method — first past (through) signal to an arbitrary area of the sheet or no sheet.
the first echo-signal from artificial reflector in test sample while monitoring the echo method, using longitudinal, transverse, repeatedly reflected transverse or normal waves;
fluctuations in the generator output under the control of the shadow method based on the decrease in the amplitude of the continuous wave with the discontinuities of the metal.
3. In the control of sheet metal continuous vibrations are applied methods of specifying and setting the sensitivity in accordance with the technical documentation on the flaw.
4. Types of waves used, the ways of setting and registration sensitivity, methods of sensitivity settings and notations of the characteristics of the control methods listed in the table.
When scanning rolled repeatedly reflected transverse wave is allowed control of the sample use the standard sample N-1 according to GOST 14782−86.
Table 2
Method |
Wave type |
Method of the task |
About- Incor- che — tion para — meter |
Value parameter |
Method sensitivity settings |
Conditi — ing about- Incor- th nie char — teris — tics | ||
Name |
About- Incor- che — nie |
nomin. | pred. off. | |||||
| Longitudinal, transverse | Diameter flat-bottomed reflector control sample, mm | 3 5 8 |
±0,12 ±0,15 ±0,15 |
For control sample with flat-bottomed reflector or ARD diagram |
D3Э D5Э D8Э | |||
| Echo | E | Longitudinal, transverse, normal | The amplitude of the echo pulses reflected from discontinuities starting from the origin, dB | 24 16 8 |
±2 ±2 ±2 |
Established operational documentation flaw or technological instructions control |
А24Э А16Э А8Э | |
| Normal | The diameter of the through hole of the control sample, mm |
1,6 3,0 5,0 |
±0,10 ±0,12 ±0,15 |
For control sample with a through hole | T1 6Э Т3Э Т5Э | |||
| Cross multiply — reflected | The depth of the reflector in the standard sample | GOST 14782−86 | For control sample or the standard sample N 1 churchyard 14782−86 |
KE | ||||
| Echo-through | ES | Longitudinal | The amplitude of the echo pulses counted from the reference mark, dB | 24 20 16 12 8 |
±2 ±2 ±2 ±2 ±2 |
Established operational documentation flaw or technological instructions for the control, the control samples do not apply |
А24ЭС А20ЭС А16ЭС А12ЭС А8ЭС | |
| Shadow | T | Longitudinal, transverse | The amplitude of the transmitted signal, which is counted from the beginning of the readout, dB |
20 (16) 14 (12) (10) 8 |
±2 ±2 ±2 ±2 ±2 ±2 |
Established operational documentation flaw or technological instructions for the control, the control samples do not apply |
А20Т А16Т А14Т А12Т А10Т А8Т | |
| Multiple-shadow | MT | The same | The amplitude of the second or the |
16 12 8 |
±2 ±2 ±2 |
The same | А16МТ2 А12МТ2 А8МТ2 (if | |
| Mirror-shadow | 3T | Longitudinal, transverse | The backwall signal counted from the start of readout, dB | 20 14 8 |
±2 ±2 ±2 |
Established operational documentation flaw or technological instructions for the control, the control samples do not apply | А203Т А143Т А83Т | |
Notes:
1. In the control of sheet metal repeatedly-shadow method scale sensitivity control set to the second previous pulse while measuring its amplitude relative to the amplitude of the first of the last (shadow) of the pulse generated by the same probing pulse.
2. The values of the sensitivities given in parentheses may be used depending on the capabilities of equipment.
3. Allowed, with the approval of normative-technical documentation for flat products, to use other values of sensitivity.
APPENDIX 3 (obligatory). THE REQUIREMENTS FOR CONTROL SAMPLES (KO)
APPENDIX 3
Mandatory
1. To adjust the sensitivity in the control of sheet metal by methods with the features with the legend D3Э, D5Э, D8Э, T1,6Э, Т3Э, Т5Э used TO.
2. TO made from flat rolled or stepped.
Flat TO made from rolled steel of thickness up to 60 mm, step — rolled thickness greater than 60 mm As both surfaces are flat TO should be such as controlled rent.
The surface condition of the scanning speed from the samples should be such as controlled rent.
3. The thickness of the flat TO should not be different from the thickness of the test hire more than 10%.
With the same thickness TO and controlled rent average value of the amplitude of the bottom or the last signal in KO should be equal to or smaller by up to 4 dB of the amplitude of the corresponding signal in a controlled rental, including rental with the corrected welding (welding) portions.
4. Distance from the surface of the scanning speed until the reflector is installed in the technical documentation for control of specific products, as hole depth must be at least 20 mm.
5. In KO there should be no defect detectable by the methods of ultrasonic testing with a sensitivity twice higher than the sensitivity level is customizable to this TO.
6. Under the control of the longitudinal or transverse waves of the artificial reflectors TO be made in the form of a hole with a flat bottom.
7. The distance between the centers of flat-bottomed reflectors and to the brim TO should be: in samples with thickness up to 100 mm — not less than 35 mm, for samples with thickness more than 100 mm — not less than 50 mm.
8. The depth of the hole is flat-bottomed reflectors installed technical documentation on the control of specific products.
9. Under the control of a two-layer sheet metal just for peeling a plating layer of artificial reflector to be performed at a depth corresponding to the location in the thickness of sheet metal border connections cladding and core layers.
10. In the control of normal waves is used FOR the artificial reflector in the form of a through drilling.
Distance , mm, from the entry point of the centre drill set technical documentation on the control of specific products.
The length of the sample shall not be less than (+100) mm, and the distance between the centre of drilling and side edges of the sample — at least 50 mm.
11. In KO shall be provided with artificial reflectors to verify compliance with the control variables and uncontrolled dead zones specified in the technical documentation for the controls or the control.
12. Each should be marked to contain the number, grade of steel and thickness of hire, from which it is made.
ANNEX 4 (required). INDICATORS OF CONTINUITY OF HRP
ANNEX 4
Mandatory
Table 3
| Indicators of continuity | |||||||
|
|
|
|
||||
| The class of continuity | The symbol features | on |
the square units of the sheet metal, no more |
| |||
| 01 | By agreement between manufacturer and consumer | ||||||
| 0 | А24Э А24ЭС+А20Т D3Э |
5 | 20 | 1,0 | 1,0 | 0,3 | 30 — sheet rolled thickness up to 60 mm, inclusive, 50 — sheet products with thickness above 60 mm |
| 1 | А16Э А16ЭС+А20Т D5Э |
10 | 50 | 2,0 | 2,0 | 0,5 | 50 |
| 2 | А8Э А8ЭС+А20Т D8Э А8МТ2+А20Т |
20 | 100 | 2,0 | 3,0 | 1,0 | 100 |
| 3 | D8Э А14Т, (А12Т), (А16Т) |
50 | 250 | - | 5,0 | 2,0 | 200 |
Notes:
1. The error of measurement conditional areas (sizes) of discontinuities indicated in the technical documentation for the control.
2. The index of continuity used in discrete linear scan, and to assess the continuity of the marginal areas of sheet metal.
The text of the document is verified by:
the official publication of the
M.: Publishing house of standards, 1988
