GOST 18576-96

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  ГОСТ 18576-96

GOST 18576−96 nondestructive testing. Railway rails. Ultrasonic methods

GOST 18576−96
Group B09

INTERSTATE STANDARD

Nondestructive testing

RAILWAY RAILS

Ultrasonic methods

Nondestructive testing. Railway rails.
Ultrasonic testing methods

MSK 77.040.20
OKP 09 2100

Date of introduction 2002−01−01

Preface

1 DEVELOPED by the research Institute of bridges, Petersburg state transport University (Institute of bridges CCGT PS)

INTRODUCED by Gosstandart of Russia

2 ADOPTED by the Interstate Council for standardization, Metrology and certification (Protocol No. 10 of October 4, 1996)

The adoption voted:

The name of the state	The name of the national authority for standardization
The Republic Of Azerbaijan	Azgosstandart
The Republic Of Armenia	Armastajad
The Republic Of Belarus	Gosstandart Of The Republic Of Belarus
The Republic Of Georgia	Gosstandart
The Republic Of Kazakhstan	Gosstandart Of The Republic Of Kazakhstan
The Kyrgyz Republic	Kyrgyzstandard
The Republic Of Moldova	Moldovastandart
Russian Federation	Gosstandart Of Russia
The Republic Of Tajikistan	Tajikstandart
Turkmenistan	The MDCSU «Turkmenstandartlary"
The Republic Of Uzbekistan	Standards
Ukraine	Gosstandart Of Ukraine

3 Resolution of the State Committee of the Russian Federation for standardization and Metrology dated July 4, 2001 N 257-St inter-state standard GOST 18576−96 introduced directly as state standard of the Russian Federation from January 1, 2002.

4 REPLACE GOST 18576−85

1 Scope

This standard applies to the rails of type R50 GOST-7174*, R65 GOST 8161 and R75 GOST 16210 in their manufacture, maintenance and repair (restoration) and establishes methods for manual and mechanized ultrasonic inspection to detect head and neck area continue of the neck to the soles of rails for internal defects (delaminations, placenow, sinks, non-metallic and foreign inclusions, cracks, defects of electric contact welding) in the range of the sensitivity control, as well as areas of abnormal mechanical stresses in the rails. The type and actual size of defects is not determined.

Allowed to extend the provisions of this standard for inspection of rails of other types.

The standard does not specify the methods of ultrasonic inspection of welding.

The need for ultrasonic inspection, the inspection scope, type and sizes of unacceptable defects set in standards or specifications on the rails.

Definitions of terms used in this standard are given in Appendix A.

2 Normative references

The present standard features references to the following standards:

GOST 12.1.001−89 System safety standards. Ultrasound. General safety requirements

GOST 12.1.003−83 System of standards of occupational safety. Noise. General safety requirements

GOST 12.2.003−91 System safety standards. Equipment production. General safety requirements

GOST 12.3.002−75 System safety standards. The process of production. General safety requirements

GOST 7174−75* railway Rails type R50. The design and dimensions
________________
* On the territory of the Russian Federation GOST R 51685−2000.

GOST 8161−75* railway Rails of type R65. The design and dimensions
________________
* On the territory of the Russian Federation GOST R 51685−2000.

GOST 14637−89 rolled plate from carbon steel of ordinary quality. Specifications

GOST 14782−86 non-destructive Control. Welded connections. Ultrasonic methods

GOST 16210−77* railway Rails type P75. The design and dimensions
________________
* On the territory of the Russian Federation GOST R 51685−2000.

GOST 17622−72 organic Glass technical. Specifications

GOST 26266−90 nondestructive testing. The ultrasonic transducers. General technical requirements

3 Refer

In this standard use the following notation and abbreviations:

 — sensitivity conditional, mm;

the conditional sensitivity, dB.

 — sensitivity are equivalent, dB.

 — the angle of entry of ultrasonic oscillations into the metal (the refracted angle), …°;

 — angle prism, probe, …°;

 — boom angle-beam probe, mm;

 — dead zone, mm;

2 — the width of the main lobe of the directivity diagram in the plane of incidence of the wave,… °;

 — the duration of the pulse emitted by the probe, ISS;

 — the reading of the attenuator corresponds to the attenuation of the echo signal from a hole of 6 mm in diameter at a depth of 44 mm in the SB-2 (- 2R,-3R) to a level at which to assess relative sensitivity, dB.

 — the time interval between the probing pulse and the echo signal from a concave cylindrical surface in CO-3P with the installation of angle-beam probe to the position corresponding to the maximum amplitude of the echo signal MS;

 — the average time of propagation of ultrasonic oscillations in the prism by angle-beam probe, ISS;

 — the angle between the two reflectors in s-4, …°;

 — the rotation angle of the probe relative to the longitudinal axis of the rail, …°;

the conditional width of the detected defect, mm;

 — conditional height of the defect detected, mm or MS;

PEP — piezoelectric Converter;

 — conventional length, mm.

The terms and their corresponding definitions are given in Appendix A.

4 controls and auxiliary devices

4.1 When control should be used:

— pulsed ultrasonic flaw detector (hereinafter detector) according to the normative documents (ND) electroacoustic (piezoelectric or electromagnetic acoustic) transducers;

— standard samples for determining the basic parameters of the control;

— accessories and apparatus for a compliance scan parameters and measurements of characteristics of the detected defects.

It is possible to use detectors with continuous emission of ultrasonic vibrations, the metrological characteristics and parameters which set the standards and (or) the technical specifications for detectors of a particular type.

Flaw detectors, transducers and standard samples used for inspection shall be certified in the prescribed manner.

4.2 To control the use flaw detectors operating on the echo-method, mirror method, Delta-method, shadow method, mirror-shadow method, at a frequency of from 0.1 to 4.0 MHz.

4.2.1 Detectors operating according to the echo, the mirror and the Delta methods, must have an attenuator. The value of the step attenuator should be less than 2.0 dB.

Under the control of the echo method is allowed to use the flaw detector without attenuator with test sensitivity conditional on standard samples CO-1P or-1 according to GOST 14782, or flaw without attenuator with automatic set up and maintain sensitivity.

4.2.2 Detectors operating in the shadow or mirror-shadow methods must have a device to measure the sensitivity of the conditional, is made on the circuit simulator defects, consisting of an attenuator and switching elements (figure 1).

Figure 1 — diagram of the device for measuring conditional sensitivity

1 - simulator of defects; 2 — attenuator; 3 - switch

Figure 1 — diagram of the device for measuring conditional sensitivity

The attenuator of the simulator defects need to be scaled in relative units from 0.1 to 0.6 or in decibels. The value of the step attenuator should be less than 0.1 or 2.0 dB, respectively.

4.3 Piezoelectric transducers at a frequency of more than 0.16 MHz — according to GOST 26266.

Allowed to use special converters, manufactured according to technical conditions (TU) and working drawings, approved in the prescribed manner.

4.4 Standard samples CO-1, CO-2P and-3P (figures 2−4) or standard samples CO-1, co-2 and co-3 according to GOST 14782 should be used to measure and verify basic parameters of the instrument and control for combined and separate schemes of piezoelectric transducers at a frequency exceeding 1.5 MHz.

Figure 2 — Standard model CO-1P

Figure 2 — Standard model CO-1P

Figure 3 is a Standard sample WITH 2P

Figure 3 is a Standard sample WITH 2P

Figure 4 is a Standard sample WITH-3R

Figure 4 is a Standard sample WITH-3R

In other cases, to test the basic parameters of the instrument and control must be used industry-standard samples or standard samples of the enterprise, certified in the prescribed manner.

4.4.1 Standard sample WITH-1R (figure 2) is used to determine the conditional sensitivity while monitoring the echo method.

A sample off-1R should be made of organic glass marks the tosp according to GOST 17622. The speed of propagation of longitudinal ultrasonic waves at a frequency of (2,5±0,2) MHz at a temperature of (20±5) °C shall be (2670±133) m/s. the Amplitude of the first bottom pulse to the thickness of the sample at a frequency of (2,5±0,2) MHz and at a temperature of (20±5) °C shall not vary by more than ±2 dB of the amplitude of the first bottom pulse to the sample-the witness, certified by bodies of the state metrological service.

Note — the Figures have holes 10Н14 on the sample WITH-1R on the surface of input of ultrasonic oscillations indicate the depth location of the center of the respective holes 2Н14 in the standard sample CO-1 according to GOST 14782.

4.4.2 Standard sample WITH 2P (figure 3) is used to determine:

the conditional sensitivity in the control echo and mirror techniques;

— dead zone;

— error of the depth gauge and the measurement error of the coordinates of the reflector;

boom Converter;

the angle of entering of ultrasonic vibrations;

— width of the main lobe of the directivity pattern of the angle-beam probe.

The sample WITH 2P must be made of steel grade 20 to GOST 14637. The speed of propagation of longitudinal waves in the sample material at a temperature of (20±5) °C shall be (5900±118) m/s.

On the lateral surface of the sample should be applied to scale values in mm and the scale of values of the angle of entering of ultrasonic vibrations from 10° to 70° with an interval of 1° in accordance with the equation

.

Zero mark of the scales must coincide with the axis passing through the centers of holes 6Н14 perpendicular to the working surface of the sample.

Note — the Arrow of the transducer is determined by the ratio

.

The value of the angle of entering of ultrasonic vibrations is calculated according to the expression

,

where , is the distance from the projection center holes 6Н14 on to the surface of the specimen to the front face of the transducer at positions corresponding to the maximum amplitude of the echo from the hole at a depth of 44 and 15 mm, respectively.

4.4.3 a reference Standard CO-3P (figure 4) used to determine:

the conditional sensitivity in the control of echo and Delta methods;

— dead zone;

— error of the depth gauge and the measurement error of the coordinates of the reflector;

boom Converter;

the angle of entering of ultrasonic vibrations;

— width of the main lobe of the directivity pattern of the angle-beam probe;

— pulse conversion factor for control of a rail or close to it according to the acoustic properties of the metal.

Sample CO-3P must be made of steel grade 20 to GOST 14637. The speed of propagation of longitudinal waves in the sample material at a temperature of (20±5) °C shall be (5900±118) m/s.

On the side, and the working surfaces of the sample should be engraved risks, passing through the center of the semicircle and the axis of the work surface. On the lateral surface of the sample cause the scale of values of the angle of entering of ultrasonic vibrations from zero to 40° with an interval of 2° from 40° to 70° with an interval of 1° in accordance with the equation

.

The zero of the scale must coincide with the axis passing through the center hole with a diameter of 6Н14 perpendicular to the working surface of the sample.

The value of 65° on the scale of angles of entry of ultrasonic oscillations should coincide with the line passing through the center of the semicircle.

4.5 Ultrasonic flaw detector specialized to identify areas of extreme mechanical stress in the rails must be capable of measuring the signal amplitude with an error of less than 1 dB and the time interval between signals with a relative error no more than 0.0001.

4.6 the Systematic verification of the parameters that determine the performance of the detectors during the complete testing of rails, may be performed using electro-acoustic devices.

The list of parameters and their validation have to be specified in the technical documentation for the control.

5 preparations for the control

5.1 rail Surface that is control, should be cleared:

— all loose scale, dirt, ice covered in a layer of the contacting liquid with the use of the piezoelectric transducer;

— all loose scale and dirt when using electromagnetic acoustic transducer.

As the contacting liquid employed is water, mineral lubricants, solution of alcohol in water and alcohol.

Surface and the composition of the contacting liquid must be indicated in the technical documentation for the control.

5.2 Preparing the instrument to the control should be performed in accordance with the technical documentation for instrumentation and control.

5.3 the Main parameters of control:

— the frequency of the excited ultrasonic vibrations;

sensitivity (conditional equivalent);

— arrow of the transducer and the position of the plane of incidence of the wave relative to the axis of the rail;

— the angle of entering of ultrasonic vibrations into the metal;

— accuracy of depth (measurement error of time interval between the signals);

— dead zone;

minimum notional size of the defect, fixed at a preset speed control;

— the duration of the probe pulse.

The list of parameters to check their values and the frequency of inspection should be established in each case in the technical documentation for the control.

5.4 Frequency of ultrasonic vibrations is measured for the duration of the period of oscillations in the echo — pulse high-frequency oscilloscope.

Allowed to measure the frequency of ultrasonic vibrations in the range of 1.5 to 4.0 MHz, radiated by the oblique transducer, according to the pattern given in Appendix V.

5.5 relative sensitivity of control of echo, the mirror and the Delta methods, the frequency of ultrasonic vibrations of more than 1.5 MHz should be measured for the sample WITH 2R (s-2) or-3R (figure 5).

Figure 5 — arrangement of converters on standard sample SB-2R (- 3R) in the measurement (setting) conditional sensitivity when controlling

- output to the generator of the detector; - the output of the receiver detector

Figure 5 — arrangement of converters on standard sample SB-2R (- 3R)
when measuring (setting) conditional sensitivity in the control:

- echo method is the mirror method, Delta-method

Conditional sensitivity control echo method allowed to measure on a standard sample WITH a-1R or-1 at the temperature stated in the certificate schedule.

Relative sensitivity when controlling the echo, the mirror and the Delta methods allowed to measure on an industry-standard samples or standard samples of the enterprise.

Relative sensitivity for control of a mirror-shadow method is measured by using the simulator defects or attenuator (figure 1) on the defect-free section of a rail, or on the sample, the parameters of which are specified in the technical documentation for the control.

When ultrasonic mode frequency less than 1.5 MHz equivalent sensitivity to measure samples, specified in the technical documentation for the control.

5.6 Arrow of the transducer should be determined on samples WITH a-3P (or SO-3 according to GOST 14782) or co-2P, and the position of incidence plane waves on samples WITH a-3P or s-3 (the graveyard 14782).

5.7 the Angle of entering of ultrasonic vibrations should be measured on samples WITH a-3P or-2P or-2.

5.8 error of the depth gauge should be checked on samples WITH a-3P or-2P or-2.

5.9 the Dead zone under the control of the echo method at a frequency of over 1.5 MHz should be checked on samples WITH a-3P or 2P and when monitoring at a frequency less than 1.5 MHz for the samples specified in the technical documentation for the control.

5.10 conditional Minimum defect size to be at a predetermined fixing speed control, you should test on the sample in accordance with the technical documentation on the control. Allowed when testing applied to electronic equipment that simulates the signals from the defects of a given relative size.

5.11 the Duration of the probe pulse should be determined using high-frequency oscilloscope measurement of the duration of the echo signal at 0.1.

You can define the duration of the echo pulse on the sample in accordance with Annex V.

6 control

6.1 rail inspection is carried out echo or mirror, or Delta, or mirror-shadow methods, or combination of methods of longitudinal and transverse waves.

The scheme and the inclusion of the location of the transducers shown in tables 1 (scheme 1−14), 2 (scheme 1−8) and 3 (schemes 1−4), where - the output of the generator; - the output to the receiver.

Table 1 — Control rail head

The sounding scheme	Timing diagrams	Control method	Infor- Matigny signal	The scheme included tion of PEP	The circuit parameters will be performed- tion	Note
1		Echo-method	The echo signal	Co- sacred		Control direct, once, twice, etc. reflected beam
2		Mirror	Mirror- NY	Production Naya		The scheme is not critical to change places converters
3		The combination of echo — mirror methods	The echo signal	Co- sacred		It is possible to include both converters in combined mode
Mirror- NY	Production Naya
4		Echo-method	The echo signal	Production Naya		The scheme is not critical to change places converters. It is possible to include probes for dual combined and combined schemes
5		Mirror — shadow	Bottom	Production Naya		Perhaps a combination with the echo-method for one or both of the probes In this case corresponding sponding probes include combined scheme
6		Echo-method	The echo signal	Production Naya		The scheme is not critical to change places converters
7		Mirror — shadow	The past senior	Production Naya		-
8		Mirror — shadow	The past senior	Production Naya		-
9		The echo method in combination with a mirror — shadow	Echo and bottom signals	Co- sacred		Possible to use PC probe. In this case, the switching circuit probe separate
10		The echo method in combination with a mirror — shadow	Echo and the first backwall signals	Production Naya		-
11		Shadow	The past senior	Production Naya		-
12		Mirror	Mirror- but otra- ciate	Production Naya		The scheme is not critical to change places converters
13		Echo-method	The echo signal	Production Naya	-	Upon excitation of ultrasonic oscillations of a frequency less than 1.5 MHz
14		The Delta method	Defrage- rovanie signals for the two Polo applications finder- Noah system	Production Naya		To determine the size and type of defect

Table 2 — Control neck-rail and its continuation in the crown and sole

The sounding scheme	Timing diagrams	Control method	Informa- tive signal	The scheme of inclusion of PEP	The parameters of the schemes	Note
1		Echo-method	The echo signal	Combined- Naya		-
2		Mirror- shadow	I, II, etc. or the ratio of bottom bottom	Separate		Possible to use PC-probe. In this case, the switching circuit converters separate
Echo-method	The echo signal	Combined- Naya
3		Mirror- shadow	Bottom	Separate		Possible use tion of waves and the type
4		Mirror- shadow	Bottom, conditioned Lenna waves: — longitudinal; — cross	Separate		-
5		Mirror- the shadow combined with the echo method	Bottom	Separate		-
The echo signal	Combined- Naya
6		Mirror- the shadow combined with the echo method	Bottom	Separately combined		-
The echo signal
7		Shadow	Past	Separate		-
8		The Delta method	Defrage- rovanie signals: from defect; — from a defect with paraotra- statement from the sole	Separate		To determine the type of defect

Table 3 — Control of rail web for cracks developing from the bolt holes

The sounding scheme	Timing diagrams	Control method	Informative signal	The scheme of inclusion of PEP	The parameters of the schemes	Note
1		Mirror- shadow («ULTRASONIC gauge»)	Bottom	Combined- Naya		A symptom of a defect is the simultaneous loss of bottom signals of both probes
2		Echo-method	The echo signal	Combined- Naya		A symptom of a defect is the reception of echo signals, respectively, from the wall of the bolt hole and corner reflector formed by the crack
3		Echo-method	The echo signal	Combined- Naya	2	A symptom of a defect is the reception of two echo signals (from the wall of the bolt hole and corner reflector formed by the crack) with the time shift of the signals relative to each other
4		Echo-method	The echo signal	Combined- Naya	, ; 2, 2;

When using an angle beam transducer, operating under a combined scheme, the testing is carried out sequentially in two opposite directions.

Permitted to use an angle beam probes, which carried out the testing in one direction.

6.2 Monitoring of rail head (table 1) exercise echo (schemes 1, 4, 13) and mirror (scheme 2) methods of using angle beam transducers.

When the frequency of ultrasonic vibrations of more than 1.5 MHz transducer include combined or separate, or dual, circuits and oriented along the axis or relative to the longitudinal axis of the rail in the part of its side edges to the corner . The nominal value of the input angle and angle must be specified in the technical documentation for the control.

When ultrasonic mode frequency less than 1.5 MHz transducers include separate scheme and is placed on the running surface of the head or on the side surfaces of the railhead in the sequence shown in scheme 13 in table 1.

May be applied to control the rail head echo method in combination with a mirror-shadow method or mirror-shadow, or shadow techniques.

6.3 Monitoring of rail web and foot, in the area of the projection of the cervix (table 2) exercise echo method (scheme 1, 2) and outside the zone of welded joint — mirror-shadow method (scheme 2, 3, 4) according to the first or second bottom signals, or the relative amplitude of bottom signals using direct or angle beam transducers are included in combined or separate schemes, or the shadow method (scheme 7).

The length of the zone of the weld joint, not controlled mirror-shadow and shadow methods must be specified in the technical documentation for the control.

Allowed control — echo and (or) mirror-shadow methods when the location of converters on the side surface of the neck.

The neck of the rail for cracks developing from the bolt holes (table 3), control echo method (scheme 2, 3, 4) or (and) mirror-shadow method (scheme 1) using one or two transducers for ultrasonic gauge.

6.4 foot rail in the area of the projection of the cervix in the absence of transverse cracks control the echo method with an angle beam transducer that is included in the combined scheme (scheme 1, table 2), with the running surface of the rail head. The incident angle of ultrasonic ray in the metal must be 45°±2°.

Control of individual sections of the rail base may be performed from the surface of the pen or the base of the bottom echo method other angles of entry of the ultrasonic beam.

6.5 Monitoring of rails in the area of welded joints is carried out after the mechanical and heat treatment echo method using an angle beam transducer that is included in the combined scheme, in accordance with GOST 14782.

The incident angle of ultrasonic ray in the metal must be 50° — 70°. The nominal value of the insertion angle indicated in the technical documentation for the control.

Inspection of rails in the head, neck and soles of the weld joint may be performed by circuits other than those specified in 6.3, 6.4 and 6.5.

6.6 Method, the circuit of inverters, main parameters, the method of excitation of ultrasonic vibrations, the circuit of the scan’s recommendations for the separation of false signals and signals from defects, and also controlled area in the cross section of the rail and uncontrolled portions of the rails must be specified in the technical documentation for the control.

7 Processing and presentation of results control

7.1 Evaluation of the continuity of the metal rails is carried out by results of the analysis of the information obtained by monitoring one or a set of methods.

7.2 Measured characteristics of the detected defects are:

when the echo, the mirror and the Delta methods:

a) ratio of the detection of the defect (relative maximum amplitude of the echo signal from the defect) or the minimum of the conditional sensitivity, which detects the defect;

b) the coordinates of the defect on the length and cross section of the rail;

C) conventional size of defect along the length of the rail at a given sensitivity control;

when the ultrasonic mirror-shadow and shadow methods:

g) ratio of the detection of the defect or the minimum of the conditional sensitivity, which detects the defect;

d) conventional size of defect along the length of the rail at a predetermined sensitivity;

e) the coordinate of the defective section along the length of the rail.

7.3 Additional information about a detected defect in the control of tilting converters of the echo method is the contingent width of a contingent to the height of the defect and mirror-shadow — depth of the defect and the ratio of the values and the conditional width of the defect detected.

Conditional conditional width and height of defect measured under the same extreme positions of the transducer in accordance with Annex B.

The need for and methods of measuring the characteristics of the defect must be installed in the technical documentation for the control.

7.4 Results of the control record in the log or Protocol or other document that must include:

— technical documentation, in accordance with which the control was monitored;

— the type of flaw and its number in the numbering system of the manufacturer;

— characteristics of the controlled object and plots, is not subject to control;

— results of checks;

— date of control;

— the name of the person who performed the inspection or the interpretation of inspection results.

The presentation of the results of monitoring specified in the technical documentation for the control.

7.5 the Rail in which the detected defect mark in accordance with the technical documentation on the control.

8 security Requirements

8.1 When carrying out ultrasonic testing of rails, the operator should be guided by GOST 12.1.001, GOST 12.1.003, GOST 12.2.003, GOST 12.3.002, Rules of technical operation of electrical installations and the Rules of technical safety for operation of electrical installations, approved by Gosenergonadzor, and safety Rules and industrial sanitation in the production of works in the road economy* approved by MPs.
________________
* On the territory of the Russian Federation the document is not valid. Are POT R O-32-CPU-652−99. — Note the manufacturer’s database.

8.2 Additional requirements regarding safety and fire safety set in the technical documentation for the control.

Annex a (informative)

Table A. 1 — Definitions of terms used in this standard

The term	Definition
Conditional sensitivity control echo method	The sensitivity, characterized by the size and depth of detected artificial reflectors in a standard sample of material with defined acoustic properties. In ultrasonic inspection of rails relative sensitivity is determined by the standard sample WITH-1R (or-1) or according to the standard model WITH a-3P or-2 or-2P. Relative sensitivity for the standard sample WITH-1R (CO-1) Express the greatest depth of the cylindrical reflector in millimeters, apparent indicators of the instrument. Relative sensitivity for the standard sample WITH a-3P or-2 or-2R expressed by the difference in decibels between the indication of the attenuator while the setting of the flaw detector and the indication corresponding to the maximum weakening, in which a cylindrical hole with a diameter of 6Н14 more record indicators of the flaw detector
Conditional sensitivity control mirror-shadow method	The sensitivity, characterized by a maximum attenuation value of the bottom signal on the reception path input, which is also clearly record the indicators of the instrument
Equivalent sensitivity control	The sensitivity, characterized by the size and depth of the natural reflectors (the end of the rail; a corner reflector formed by the end face of the rail; a bolt or another hole in the rail) or artificial reflectors in the sample rail
The coefficient of detectability of defect ultrasonic mirror-shadow method	The coefficient corresponding to the maximum attenuation of the amplitude of the first backwall signal caused by the defect
The ratio of the detection of the defect echo method	The coefficient corresponding to the ratio of the maximum amplitude of the echo signal from the defect to the maximum amplitude of the echo signal from a cylindrical hole with a diameter of 6 mm at a depth of 44 mm in the standard sample so-2 (- 2R) or-3P
Conventional size of defect along the length of the rail	Size in millimeters corresponding to the length of the zone of displacement of the transducer along the rail, which record the signal from defect at a given conditional sensitivity flaw detector
Conditional width of the defect	Size in millimeters corresponding to the length of the zone between the extreme positions of the inclined transducer are moved in a plane of incidence of the ultrasonic waves, within which is recorded the signal from the defect at a given conditional sensitivity flaw detector
Conditional height of the defect	A size corresponding to the difference of depth values of the location of the defect, measured at the extremes of the inclined transducer are moved in a plane of incidence of the ultrasonic waves, within which is fixed the signal from the defect at a given conditional sensitivity flaw detector
Conditional length of the defect	Size in millimeters corresponding to the length of the zone between extreme positions angle beam transducer that is moved along a plane oriented perpendicular to the plane of incidence of the ultrasonic waves, within which is recorded the signal from the defect at a given conditional sensitivity flaw detector
The boom of the piezoelectric transducer	Distance from the exit point of the ultrasonic beam angle beam transducer to the front face

APPENDIX B (mandatory). General view of the certificate-the schedule to the standard sample made of organic glass

APPENDIX B
(required)

Certificate-schedule communicates the conditional sensitivity in millimeters in the original standard sample so-1 with the conditional sensitivity in decibels at a standard sample so-2 (or 2P, or-3P), reflector diameter 10Н14 in the certified sample WITH-1R at the frequency of ultrasonic vibrations (2,5±0,2) MHz, a temperature of (20±5) °C and the angles of the prism =40°±1° for drives of a specific type.

Figure B. 1 published schedule for the initial sample WITH-1R. To construct an appropriate chart to a specific certified sample WITH the-1R that does not meet the requirements of 4.4.1 of this standard, under the above conditions determine in decibels the difference of the amplitudes from the reflectors 20 N and 50 N in diameter 10Н14 in the certified sample, and the amplitude of the reflector diameter 6Н14 at a depth of 44 mm in sample SB-2 (or 2P, or-3P) by the formulas:

; ,

where  — the value of the attenuator corresponds to the attenuation of the echo signal from a hole with a diameter of 6Н14 in the sample co-2 (CO-2P or-3P) to the level at which to assess relative sensitivity, dB.

 — reading attenuator, in which the amplitude of the echo signal from the test holes with the number in the certified sample reaches a level at which to assess relative sensitivity, dB.

Figure B. 1

The calculated values mark the points on the chart and connect with a straight line (an example plot is shown in figure B. 1).

Examples of application of the certificate-graphics

Monitoring is carried out by the detector with the transducer frequency of 2.5 MHz with the angle of the prism with a radius of the piezoelectric plate mm, manufactured in accordance with specifications.

The flaw detector is equipped with a model CO-1P, serial number, with certificate-schedule (see figure B. 1).

Examples

1 — Technical documentation for the control is set to conditional sensitivity of 40 mm.

The specified sensitivity will be played, if you configure a flaw at hole N 45 in the sample WITH a-1R, serial number.

2 — Technical documentation for the control is set to conditional sensitivity of 14 dB. The specified sensitivity will be played, if you configure a flaw on hole No. 35 in the sample WITH a-1R, serial number.

ANNEX b (informative). Sample to measure the frequency of ultrasonic oscillations and the pulse duration angle beam transducer (angle of the prism is larger than the first and less than the second critical)

THE APP
(reference)

Material: steel grade 20 to GOST 14637.
________________
* Dimensions for reference.

Figure B. 1

Notes

1 the Angle determined by the protractor or calculated values and , measured with an accuracy of at least 0.1 mm; ; the value marked on the sample.

2 a Millimeter scale engraved or pasted. The zero of the millimetre scale should coincide with the plane of the corner reflector with an accuracy of ±0.1 mm.

3, the Line passing through the projection point of intersection of the corner reflectors perpendicular to the surface B, engrave; deviation of line engraving from the preset position — no more than ±0,1 mm.

Frequencies of elastic vibrations , Hz wavelength , mm pulse duration , is calculated by the formula:

,

where is the measured value of the propagation velocity of shear waves in the sample material, mm/s; if it is impossible to measure the value of it is taken equal to 3260·10mm/s;

the true value of the angle , … °;

 — the maximum distance from the line passing through the projection of the point of intersection of corner reflectors, to the line perpendicular to the surface through the middle (point of the input beam) drive installed in a position in which the trailing edge of the first echo signal still overlaps with the rising edge of the second echo signal from the corner reflectors at the level of the scan lines, mm.

- the average of the distances between neighboring positions of the Converter in which the failure between the two echo signals observed on the screen of a cathode-ray tube, maximum, mm;

- distance from the projection of the angular reflector on the working surface of the sample to the exit point when installing the inverter in the position at which the amplitude of the echo signal from the reflector maximum.



The text of the document is verified by:
the official publication of the
M.: IPK Publishing house of standards, 2001