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NB/T 47013.3-2015 (NB/T47013.3-2015)

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NB/T 47013.3-2015English265 Add to Cart 0--10 minutes. Auto-delivery. Nondestructive testing of pressure equipments - Part 3: Ultrasonic testing [Including 2018XG1] NB/T 47013.3-2015 Valid NB/T 47013.3-2015


NB/T 47013.3-2015: PDF in English (NBT 47013.3-2015)
NB/T 47013.3-2015
ENERGY INDUSTRY STANDARD
OF THE PEOPLE'S REPUBLIC OF CHINA
ICS 77.040.20
H 26
Replacing JB/T 4730.3-2005
Nondestructive testing of pressure equipment
- Part 3: Ultrasonic testing
[Including Modification 2018XG1]
ISSUED ON: APRIL 02, 2015
IMPLEMENTED ON: SEPTEMBER 01, 2015
Issued by: National Energy Administration
Table of Contents
Foreword ... 5
1 Scope ... 9
2 Normative references ... 9
3 Terms and definitions ... 10
4 General requirements ... 11
5 Ultrasonic testing methods and quality grading for standby raw material or
components of pressure equipment ... 18
6 Ultrasonic testing method and quality grading of welded joint for pressure
equipment ... 49
7 Ultrasonic measuring methods for thickness of pressure equipment ... 77
8 Ultrasonic testing methods of in-service pressure equipment ... 84
9 Ultrasonic testing records and reports ... 96
Annex A (Normative) Requirements for electrical performance indicators of
ultrasonic testing instruments ... 98
Annex B (Normative) Requirements for performance indicators of probe used
for ultrasonic testing ... 102
Annex C (Normative) Requirements for performance of double-crystal straight
probe ... 104
Annex D (Normative) Ultrasonic testing methods and acceptance standard for
plates used for pressure equipment by using an angle probe... 106
Annex E (Normative) Ultrasonic testing methods (by using an angle probe) and
quality classification of steel forgings used for pressure equipment ... 109
Annex F (Normative) Ultrasonic testing methods (by using an angle probe) for
austenitic steel forgings used for pressure equipment ... 112
Annex G (Normative) Ultrasonic testing method and quality classification of the
welding overlay of pressure equipment ... 114
Annex H (Normative) Ultrasonic testing method and quality classification of the
butt joints of pressure equipment made by aluminum & aluminum alloy and
titanium ... 119
Annex I (Informative) Ultrasonic testing method and quality classification of the
butt joints of austenitic stainless steel ... 123
Annex J (Normative) Ultrasonic testing method of the curved longitudinal butt
joints of pressure equipment ... 132
Annex K (Normative) Ultrasonic testing method of the curved circumferential
butt joints of pressure equipment ... 136
Annex L (Normative) Ultrasonic testing method of fillet joints for nozzles and
shells (or heads) of pressure equipment ... 139
Annex M (Normative) Ultrasonic testing method of T-type welding joints ... 145
Annex N (Normative) Specific requirements for the ultrasonic testing for welding
joints of different types ... 148
Annex O (Normative) CSK-III A Test specimen ... 160
Annex P (Normative) Determination of the loss difference during sound energy
transmission ... 161
Annex Q (Normative) Echo dynamic patterns ... 165
Annex R (Normative) Defect Height Measurement Method (I) Measure defect
height by the endpoint wave diffraction method ... 169
Annex S (Normative) Defect Height Measurement Method (II) The End Echoes
Diffraction Method to Measure the Defect Height ... 176
Annex T (Normative) Defect Height Measurement Method (III) Using -6 dB
method for measuring defect heights ... 179
Modification Notification of Industry Standard NB/T 47013.3-2015 (2018XG1)
... 182
Foreword
This Standard, NB/T 47013 “Nondestructive testing of pressure equipment”, consists
of the following 13 parts:
- Part 1: General requirements;
- Part 2: Radiographic testing;
- Part 3: Ultrasonic testing;
- Part 4: Magnetic particle testing;
- Part 5: Penetrant testing;
- Part 6: Eddy current testing;
- Part 7: Visual testing;
- Part 8: Leak testing;
- Part 9: Acoustic emission testing;
- Part 10: Ultrasonic time of flight diffraction technique testing;
- Part 11: X-ray digital radioscopic examination;
- Part 12: Magnetic flux leakage testing;
- Part 13: Pulsed eddy current testing.
This Part is Part 3: Ultrasonic testing of NB/T 47013.
This Part is drafted according to the rules provided in GB/T 1.1-2009 “Directives for
standardization - Part 1: Structure and drafting of standards”.
This Part replaces JB/T 4730.3-2005 “Nondestructive testing of pressure equipment -
Part 3: Ultrasonic testing”. The main technical changes are as follows, compared with
JB/T 4730.3-2005:
- ADD “terms and definitions”, including terms and definitions related to ultrasonic
testing in the former JB/T 4730.1;
- REPLACE JB/T 10061 “Shape A Pulse Reflection Ultrasonic Flaw Detector -
General Technology Condition” WITH GB/T 27664.1 “Nondestructive Testing
Performance and Inspection of Ultrasonic Testing Equipment - Part 1: Instrument”.
Put forward more scientific requirements for performance of ultrasonic testing
equipment;
- ADD specific performance indicator requirements for ultrasonic test instrument
and probe;
- ADD requirements for calibration, inspection, operational inspection; and check of
ultrasonic test instrument and probe;
- ADD “safety requirements”; and put forward requirements for safety of personnel
in process of ultrasonic test;
- ADD requirements for process files; and list out the related factors to formulate
process procedure;
- RE-DIVIDE types (standard test block and reference block) of test blocks used in
this part; and such division was implemented mainly based on domestic general
standards, instead of dividing types of standard test block and reference block in
this Part;
- ADJUST the sequence of “ultrasonic testing methods and quality grading for
standby raw material or components of pressure equipment”, so as to formulate
in accordance with the order of plate, composite plate, carbon steel and low alloy
steel forgings, steel bolt billet, austenite steel forgings, seamless steel pipe and
so on;
- COMBINE ultrasonic testing methods and quality grading of carbon steel and low
alloy steel, aluminum and aluminum alloy plate, titanium and titanium alloy plate,
as well as nickel and nickel alloy plate, austenite stainless steel and duplex
stainless steel, and so on. Redesign reference blocks. The detection sensitivity
shall be mainly determined by flat bottom hole distance amplitude curves of
reference blocks. Modify the quality grade requirements to stricter requirements
for qualified indicators at all levels. As the plates in JB/T 4730.3-2005 have lower
requirements for testing quality level, it is difficult to control the quality
requirements, and moreover, as it has larger difference from specific indicators as
required by ISO, EU EN and other related quality requirements, therefore, it
modifies the quality grading in accordance with EU EN and other standards;
- INTEGRATE the contents in two chapters of 2005-version, “ultrasonic detection
and quality grading for butt joint of pressure equipment" and "ultrasonic detection
and quality grading for pipe and pressure pipe ring of pressure equipment”.
Classification shall be conducted according to the type of welded joint, base
material nominal thickness and the size of detecting surface curve rate;
- Applicable scope of welded joint base material nominal thickness of pressure
equipment is expanded from 8 mm ~ 400 mm to 6 mm ~ 500 mm;
- REDESIGN the position and the number of the artificial reflector on CSK-IIA and
CSK - IVA blocks. In this way, it not only guarantees the coverage of the detection
area coverage, but also is suitable for adjustment of the straight probe benchmark
sensitivity. New CSK-IIA block is applicable for work piece with thickness scope of
6 mm ~ 200 mm, mainly referring to the European Union (EN) and Japanese
standard (JIS). New CSK-IVA block is applicable for work piece with thickness
scope greater than 200 mm ~ 500 mm, and makes improvement on basis of mainly
referring to the ASME codes. The block diameter of artificial reflector shall be 6
mm;
- REFINE the weld ultrasonic testing requirements for different types. It involves flat
butt joint, T-shaped welded joint, plug-in Angle joint, L-shaped welded joint,
placement type pipe and cylinder (or seal-end socket) angle joint, cross welding
joint, embedded type pipe and cylinder (or end socket) butt joint etc.
- REDESIGN the GS test block. Increase the circular arc surfaces etc. It is mainly
beneficial to adjusting time base of arc probe;
- LIMIT the length of non-crack defect in Zone I in quality grade of weld joint;
- ADJUST overall formulation structure involved in weld joint ultrasonic testing. The
ultrasonic testing method of connecting pipe and cylinder (head) angle joint,
ultrasonic testing method of T-shaped weld joint, ultrasonic testing method and
quality grading of surfacing welding layer are included into the annex;
- ADD “ultrasonic thickness measurement method for the pressure equipment” in
accordance with actual testing requirements, including measurement method for
stainless steel surfacing layer thickness;
- When pressure equipment is used to conduct ultrasonic detection, ADD failure
mode of host materials, components or welded joint which may be caused in use
process or analysis results of risk evaluation to select ultrasonic testing method,
detection parts and detection proportion.
This Part is proposed by and shall be under the jurisdiction of National Technical
Committee on Boiler Pressure Vessel of the Standardization Administration of China
(SAC/TC 262).
Drafting organizations of this Part: Hefei General Machinery Research Institute, China
Special Equipment Inspection Institute, Shanghai Electric and Nuclear Power
Equipment Co., Ltd., China First Heavy Machinery Group Dalian Hydrogenation
Reactor Manufacturing Co., Ltd., Jiangsu Special Equipment Safety Supervision and
Inspection Research Institute, and Lanzhou Lanshi Heavy Equipment Co., Ltd.
Main drafters of this Part: Yan Changzhou, Zheng Hui, Xu Zunyan, Zhou Fengge, Zhou
Yufeng, Tao Yuanhong, Zheng Kai, Gu Jie, Zhang Baozhong and Pan Qianghua.
The historical version of the standards replaced by this Part are as follows:
- JB 4730-1994, JB/T 4730.3-2005.
Nondestructive testing of the pressure equipment -
Part 3: Ultrasonic testing
1 Scope
1.1 This Part of NB/T 47013 specifies the pressure equipment shall adopt ultrasonic
testing method and quality grading requirements in which shape A pulse reflection
ultrasonic detector is used to test work piece defect.
1.2 This Part is applicable to ultrasonic detection for metal material system pressure
equipment with raw materials or components and welded joint, and be applied to
ultrasonic detection of metal materials used in the pressure equipment.
1.3 This Part specifies ultrasonic measuring method for thickness of the pressure
equipment.
1.4 Ultrasonic detection of supporting parts and structural piece related to the pressure
equipment can also refer to this part.
2 Normative references
The following documents are necessary to the application of this document. For all
dated references, only the dated edition applies to this document. for all undated
references, the latest edition (including all amendments) applies.
GB/T 11259 Non-destructive testing - Practice for fabrication and control of steel
reference blocks used in ultrasonic testing
GB/T 12604.1 Non-destructive testing - Terminology - Terms used in ultrasonic
testing
GB/T 27664.1 Non-destructive testing - Characterization and verification of
ultrasonic test equipment - Part 1: Instruments
GB/T 27664.2 Non-destructive testing - Characterization and verification of
ultrasonic test equipment - Part 2: Probes
JB/T 8428 Non-destructive testing - Blocks for ultrasonic testing
JB/T 9214 Non-destructive testing - Practice for evaluating performance
characteristics of A scope ultrasonic pulse - Echo testing systems
JB/T 10062 Testing methods for performance of probes used in ultrasonic flaw
detection
NB/T 47013.1 Nondestructive testing of pressure equipment
3 Terms and definitions
The following terms and definitions in GB/T 12604.1 and NB/T 47013.1 are applicable
to this Part.
3.1
Reduction of backwall echo caused by the presence of discontinuities BG/BF
In time of forging test, ratio of the initial backwall echo BG in the intact area close to
defect place and the initial backwall echo BF within the defect place, expressed as dB
value.
3.2
Grouped discontinuities
In time of forging test, there are five or more defect reflection signals within 50 mm
acoustic distance at the same time on the display screening line, or five or more defect
reflection signals within the same depth scope were found on the inspection surface
of 50 mm × 50 mm, and the reflection amplitude are greater than or equal to defect of
an equivalent flat bottom hole diameter.
3.3
Reference sensitivity
It refers to sensitivity when height of reference block artificial reflection echo or height
of inspected work piece bottom are adjusted to a certain reference.
3.4
Scanning sensitivity
Based on reference sensitivity, dB value (increment) shall be properly improved in
accordance with surface condition, testing defect requirements and probe types to
conduct sensitivity of actual detection.
3.5
Through thickness dimension of the flaw
The size of defect on the direction of base material nominal thickness.
3.6
Echodynamic patterns
Envelope curve of probe moving distance and the corresponding defect reflector echo
envelope changes.
3.7
Base material nominal thickness
Base material nominal thickness is defined as follows:
a) For plate butt joint, when the thickness of the parent materials at both sides of
the weld is equal, the base material nominal thickness t is the nominal thickness
of the parent materials at thinner side;
b) For plug-in connecting pipe Angle joint, base material nominal thickness t is the
nominal thickness of cylinder or end socket; placement connecting pipe and
cylinder (or end socket) Angle joint, the base material nominal thickness t is
nominal thickness of connecting pipe;
c) For T-shaped weld joint, the base material nominal thickness t is nominal
thickness of plate.
4 General requirements
4.1 Inspector
4.1.1 The general requirements for ultrasonic testing personnel shall be in conformity
with the relevant provisions in NB/T 47013.1.
4.1.2 Ultrasonic testing personnel shall master basic knowledge about certain metal
materials, equipment manufacturing and installation, welding and heat treatment etc.,
shall be familiar with material, geometry size and acoustic properties of the tested work
piece etc., and shall make analysis, judgment and processing to problems found in
inspection.
4.2 Testing equipment and instrument
4.2.1 Product quality qualification certificate of instrument and probe
It shall at least give out preheating time, low voltage alarm or automatic shutdown
voltage with low voltage, pulse repetition frequency, effective output impedance, firing
pulse voltage, pulse rise time and firing pulse width (using square wave pulse impact
as firing pulse), receiving circuit band and other main performance parameters in
product quality certification of ultrasonic testing instrument the probe shall provide
center frequency, bandwidth, impedance or static capacitance, relative pulse echo
sensitivity and Angle probe beam performance (including probe frontier distance (shot
point), Value K (refraction Angle β) and other major parameters.
4.2.2 Test instrument, probe and combined performance
4.2.2.1 Testing instruments
Use A type pulse reflection ultrasonic detector, and the working frequency shall include
at least frequency range of 0.5 MHz ~ 10 MHz based on -3 dB measurement, test
conditions and parameters of each performance in the ultrasonic instrument shall meet
the requirements of annex A and provide certification documents. The test method
shall be based on provisions in GB/T 27664.1.
4.2.2.2 Probe
Circular wafer shall not be greater than 40 mm in diameter, and either side length of
square chip shall not be more than 40 mm in general. The performance indicators shall
meet the requirements of annex B and provide certification documents. The test
method shall be based on provisions in GB/T 27664.2.
4.2.2.3 Combined performance of instrument and probe
4.2.2.3.1 Combined performance of instrument and probe includes horizontal linear,
vertical linear, combined frequency, margin sensitivity, blind area (only limited to
straight probe) and far field resolution.
4.2.2.3.2 It shall measure combined performance of instrument and probe in the
following cases:
a) Newly purchased ultrasonic testing instrument and (or) probe;
b) After instrument and probe are repaired or have major components replaced;
c) When inspectors doubted.
4.2.2.3.3 The horizontal linear deviation is not more than 1 %, and vertical linear
deviation is not more than 5 %.
4.2.2.3.4 The deviation between combined frequency of instrument and probe and
nominal frequency of probe shall not be more than plus or minus 10 %.
4.2.2.3.5 Combined performance of instrument and straight probe shall meet the
following requirements:
a) Sensitivity allowance shall not be less than 32 dB;
b) Under reference sensitivity, for probe with nominal frequency of 5 MHz, the blind
area is not more than 10 mm; for probe with the nominal frequency of 2.5 MHz,
the blind area is not more than 15 mm;
c) The far field resolution of straight probe is not less than 20 dB.
4.2.2.3.6 Combined performance of instrument and angle probe shall meet the
following requirements:
a) Sensitivity allowance shall not be less than 42 dB;
b) The far field resolution of angle probe is not less than 12 dB.
4.2.2.3.7 When it reached the maximum detection acoustic distance of the detected
work piece, the effective sensitivity allowance shall be not less than 10 dB.
4.2.2.3.8 The testing method for combined frequency of instrument and probe shall be
based on provisions in JB/T 10062, and testing method for other combined
performance shall refer to provisions in JB/T 9214.
4.2.3 Test block
4.2.3.1 Reference block
4.2.3.1.1 Reference block is a material block with specified chemical composition,
surface roughness, heat treatment and geometry, used for evaluating and calibrating
ultrasonic testing equipment, which is test block used for calibrating instrument probe
system performance. Reference block used by this part is No. 20 high-quality carbon
structural steel CSK-IA, DZ-I and DB-P Z20-2.
4.2.3.1.2 See this part for specific shape and size of CSK - IA test block, and see JB/T
9214 for specific shape and size of DZ-O and DB-P Z20-2.
4.2.3.1.3 The manufacture of reference test block shall meet the requirements of JB/T
8428; the manufacturer shall provide product quality certificate and ensure that the
maximum reflection amplitude difference shall be less than or equal to 2 dB when each
reference test block manufactured is compared to national standard sample or similar
reference test block with quantity transmission under same test condition.
4.2.3.2 Reference block
4.2.3.2.1 Reference block refers to test block with similar chemical composition as
inspected work piece or material and including reference reflector with clear meaning
(reflector shall be made by machining way), to regulate amplitude and acoustic
distance of the ultrasonic testing equipment, so as to compare tested defect signal with
signals produced by the known reflector, namely test block used for inspection.
4.2.3.2.2 Overall dimensions of reference block shall be able to represent features of
inspected work piece, and thickness of test block shall be corresponding to thickness
of inspected work piece. If it involved inspection of butt joint with different thickness,
the selection of the test block thickness shall be determined by thickness of the larger
one.
4.2.3.2.3 The reference block shall be made by materials with same or similar acoustic
performance as the inspected materials. When straight probe is used for detection, it
is not allowed having defects with flat bottom quantity diameter greater than or equal
to Φ2 mm.
4.2.3.2.4 The shape, size and quantity of reference block artificial reflector used for
different inspected work piece ultrasonic inspection shall comply with the provisions in
relevant sections of this Part.
4.2.3.2.5 When it clearly requires size accuracy of reference block in this part, it shall
provide related evidence document, and it shall refer to provisions in JB/T 8428 without
clear requirements.
4.2.4 Coupling agent
4.2.4.1 Sound permeability of coupling agent shall be better and not damage detection
surface detection, such as machine oil, chemical paste, glycerin and water etc.
4.2.4.2 Control on content of coupling agent contaminants
4.2.4.2.1 Adding content of coupling agent shall not be greater than 250 mg/L if used
on nickel-based alloy.
4.2.4.2.2 The total halogen (chlorine and fluorine) of coupling agent shall not be greater
than 250 mg/L if used on austenite stainless steel or titanium.
4.2.5 Calibration, verification, operation review and check requirements for ultrasonic
testing equipment and instrument
4.2.5.1 Calibration, verification and operation review shall be conducted on reference
test block. The main beam of the probe shall vertically align to reflector’s reflective
surface to obtain stable and the largest reflected signal.
4.2.5.2 Calibration or verification
4.2.5.2.1 It shall at least calibrate horizontal linear, vertical linear, combined frequency,
blind area (only limited to straight probe), margin sensitivity and resolution in combined
performance of the ultrasonic instrument and probe as well as attenuator precision of
the instrument once a year, and record. Test is required to meet provisions in 4.2.2.3.
4.2.5.2.2 It shall at least review surface corrosion and mechanical damage of reference
test block and reference block once a year.
4.2.5.3 Operational review
4.2.5.3.1 It shall at least review horizontal linear and vertical linear of analog ultrasonic
detector every 3 months or digital ultrasonic detector every 6 months in combined
performance of the instrument and probe, and record. Test is required to meet
provisions in 4.2.2.3.
4.2.5.3.2 It shall at least review blind area (only limited to straight probe), margin
sensitivity and resolution every 3 months, and record. Test is required to meet
provisions in 4.2.2.3.
4.2.5.4 Inspection
4.2.5.4.1 It shall check whether instrument and equipment appearance, cable
connection and boot signals are normal before each test.
4.2.5.4.2 When angle probe is used, it shall measure incidence point (frontier distance)
and refraction angle (value K) before inspection.
4.2.5.5 Precaution on calibration, operational verification and check
In time of calibration, operational verification and check, the controller to affect the
instrument linear (such as inhibit or filter switch etc.) shall be placed in “off” position or
at the lowest level.
4.3 Test of process file
4.3.1 Test of process file includes process procedures and operating instructions
4.3.2 The process procedure shall also specify specific scope or requirements for
related factors listed in table 1 and relevant chapters and section, in addition to meet
requirements in NB/T 47013.1. When changes in related factors are beyond the rules,
it shall formulate again or revise the process procedures.
4.3.3 The operating instructions shall be formulated based on the content of process
procedure and test requirements of inspected work piece. In addition to meet
requirements in NB/T 47013.1, the content shall also include:
a) Test technology requirements: test technology (straight probe test, angle probe
test, direct contact method, and immersion method etc.) and test wave form etc.;
b) Test object: category of pressure equipment, name, specification and material of
tested object, and heat treatment state, test parts etc.;
c) Test equipment: instrument type, probe specification, coupling agent, test block
type, project, timing and performance indicators of instrument and probe
performance test etc.;
d) Technical parameters related to test process: scanning direction and scanning
range, defect quantitative method, inspection records and evaluation
requirements, and test schematics etc.
Table 1 -- Related factors involved in ultrasonic testing procedure
S/N Content of related factors
1 Work piece shape includes specification and material etc.
2 Requirements for test surface
3 Testing technology (straight probe test, angle probe test, direct contact method, and immersion method etc.)
4 Probe refraction angle and its waveform in the work piece (transverse wave and longitudinal wave); probe nominal frequency, wafer size and wafer shape
5 Testing instrument type
6 Coupling agent type
7 Calibration (test block and calibration method)
8 Scanning direction and scanning scope
9 Scanning mode (manual or automatic)
10 Defect quantitative method
11 Computer data acquisition (when used); automatic alarm and/or recording device (when used)
12 Personnel qualifications; test report requirement
4.3.4 The operating instructions shall be performed with process verification before
initial application. The verification method can be conducted on related reference block.
The verification content includes sensitivity within test scope, signal-to-noise ratio and
whether meet the testing requirements.
4.4 Safety requirements
Test place, environment and safety protection shall comply with provisions in NB/T
47013.1.
4.5 Test implementation
4.5.1 Test preparation
4.5.1.1 When the pressure equipment is manufacturing, installing and testing,
selection of ultrasonic testing time and test rate shall be consistent with the provisions
of the relevant laws and regulations, standards and related technical documents.
4.5.1.2 Confirmed test surface shall ensure that the tested part of work piece can be
fully tested.
4.5.1.3 Surface quality of weld shall be qualified through appearance check. It shall
remove all paint, dirt and rust, splash and contaminants to influence test on test surface
(area passing probe), and its surface roughness shall conform to the requirements of
the test. The irregular state on the surface shall not affect the validity of test results.
4.5.2 Scanning coverage
In order to ensure ultrasonic sound beam can scan the overall tested area of work
piece while testing, every scanning coverage of the probe shall be greater than probe
diameter or 15 % of the width or it shall give priority to satisfy the demands of test
coverage requirements in related chapters.
4.5.3 Movement speed of the probe
Probe scanning speed shall not exceed 150 mm per second commonly. When
automatic alarm device is used for scanning, the scanning speed shall be based on
the reference test to determine.
4.5.4 Scanning sensitivity
Setting of scanning sensitivity shall comply with the provisions in the relevant chapter.
4.5.5 Sensitivity compensation
a) Coupling compensation: in time of testing and defect quantitative, compensation
shall be made to coupling loss caused by difference between reference block
and surface roughness of tested work piece;
b) Attenuation compensation: in time of testing and defect quantitative,
compensation shall be made to sensitivity decline and defect quantitative error
caused by difference between reference block and material attenuation of tested
work piece;
c) Hook face compensation: in time of testing and defect quantitative, for work piece
with hook tested face, compensation shall be made to coupling loss caused by
difference between work piece and radius of reference block curvature.
4.5.6 Review of instrument and probe system
4.5.6.1 Review shall be carried out to the system in the following cases:
a) When there are changes in probe, coupling agent and instrument regulation;
b) When it is suspected that scanning range or scanning sensitivity have changes;
c) It has worked for more than 4 hours continuously;
d) When the work is done.
4.5.6.2 Review of the scanning range
If the offset on the scanning line at any point exceeds 10 % of reading on the scanning
line at this point or 5 % of the full scanning range, it shall readjust scanning range, and
review shall be carried out to all tested positions since last review.
4.5.7 Review of scanning sensitivity
While reviewing, if the scanning sensitivity or distance within tested scope are found
to have artificial reflector echo amplitude dropping 2 dB on wave curves in any depth,
review shall be carried out to all tested positions since last review; if the echo amplitude
rises 2 dB, it shall reevaluate all recording signals.
5 Ultrasonic testing methods and quality grading for
standby raw material or components of pressure
equipment
5.1 Scope
This chapter specifies ultrasonic testing methods and quality grading for standby raw
material or components of pressure equipment.
5.2 Ultrasonic testing process files for standby raw material or components of
pressure equipment
Ultrasonic testing process files for standby raw material or components of pressure
equipment shall also include related factors listed in table 2, in addition to meet
requirements in 4.2.
Table 2 -- Related factors involved in ultrasonic testing process procedure for
raw material or components
S/N Content of related factors
1 Product shape (plate, pipe material, and forgings etc.)
2 Tested time (such as before or after heat treatment)
3 Tested scope
4 Quality acceptance level
5.3 Ultrasonic testing method and quality grading for standby plate of pressure
equipment
5.3.1 Scope
5.3.1 This article is applicable for ultrasonic testing method and quality grading for
standby plate of pressure equipment made of by carbon steel and low alloy steel with
thickness o...
......
 
(Above excerpt was released on 2017-06-08, modified on 2021-06-07, translated/reviewed by: Wayne Zheng et al.)
Source: https://www.chinesestandard.net/PDF.aspx/NBT47013.3-2015