Codeofchina.com is in charge of this English translation. In case of any doubt about the English translation, the Chinese original shall be considered authoritative.
This Standard "Nondestructive Testing of Pressure Equipments" (NB/T 47013) comprises 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 4: Sound Emission Testing;
- Part 10: Ultrasonic Time of Flight Diffraction Technique;
- Part 11: X-ray Digital Radioscopic Testing;
- Part 12: Magnetic Flux Leakage Testing;
- Part 13: Pulsed Eddy Current Testing.
This part is Part 3 of NB/T 47013: Ultrasonic Testing.
This Part was drafted according to the rules given in "Directives for Standardization - Part 1: Structure and Drafting of Standards" (GB/T 1.1-2009).
This Part supersedes "Nondestructive Testing of Pressure Equipments - Part 3: Ultrasonic Testing" (JB/T 4730.3-2005). Compared with JB/T 4730.3-2005, this Part has the following main technical changes:
- "Terms and Definitions" was added, including the terms and definitions concerning ultrasonic testing in the former JB/T 4730.1;
- "Commonly Used Specification for A-mode Ultrasonic Flaw Detector Using Pulse Echo Technique" (JB/T 10061) was superseded by "Non-destructive Testing - Characterization and Verification of Ultrasonic Test Equipment - Part 1: instruments" (GB/T 27664.1), and more scientific requirements for the performance of ultrasonic testing equipment were proposed;
- The specific performance indexes of ultrasonic testing instrument and probe were added;
- Requirements for probe calibration, checking, operation checking and inspection of ultrasonic testing instrument and probe were added;
- "Safety Requirements" was added, proposing safety requirements for the personnel during ultrasonic testing;
- The requirements of process documents were added and relevant factors regarding process specification were listed;
- The types of test blocks (standard test block and reference block) used in this Part were re-defined mainly according to the requirements of relevant general standards in China instead of defining the types of standard test blocks and reference blocks in this Part separately;
- The contents order of "ultrasonic testing method and quality grading of raw materials or spare parts for the pressure equipment" was adjusted to plate, clad plate, carbon and low-alloy steel forging, steel bolt blank, austenitic steel forging and seamless steel pipe, etc.;
- The ultrasonic testing methods and quality grading of carbon steel and low-alloy steel plates, aluminium and aluminium alloy plates, titanium and titanium alloy plates, nickel and nickel alloy plates, as well as austenitic stainless steel and duplex stainless steel plates were merged. Reference block was redesigned. The testing sensitivity was mainly determined according to the distance amplitude curve of flat bottom hole of reference block. The requirements of quality grades were modified and the acceptable indexes of all grades were stricter. In JB/T 4730.3-2005, the requirements of quality grades of plates were lower, and insufficient to control the quality any more. Moreover, there existed a large gap from the specific indexes of relevant quality requirements in ISO, EN standards. Therefore, the quality grading was modified by reference to EN standards, etc.;
- Two Chapters of 2005 Edition "ultrasonic testing and quality grading for butt joint of the pressure equipment" and "ultrasonic testing and quality grading for circumferential butt joint of pipes and pressure pipeline of the pressure equipment" were integrated. Grading was made according to the welded joint type, workpiece thickness and curvature of testing surface, etc.;
- The applicable workpiece thickness of welded joint of pressure equipment expanded from 8mm~400mm to 6mm~500mm;
- The position and quantity of artificial reflector on CSK-IIA and CSK-IVA test blocks were redesigned. This not only guarantees the coverage over the testing area, but also applies to the regulation of reference sensitivity of normal probe. New CSK-IIA test block is applicable to workpiece thickness of 6mm~200mm by mainly reference to EN and JIS standards; new CSK-IVA test block is applicable to workpiece thickness larger than 200mm~500mm by making improvement mainly based on ASME codes. The artificial reflector diameters of test blocks were unified to Φ6mm;
- Ultrasonic testing requirements for different types of welded joints were further detailed, including plate welded joint, T-type welded joint, insert-type nozzle fillet joint, L-type welded joint, fillet joint between abutting nozzle and cylinder (or head), cruciform joint, butt joint between embedded nozzle and cylinder (or head), etc.;
- GS test block was redesigned. Arc reflecting surface and others were added, which is mainly beneficial to the time baseline adjustment of cambered surface probe;
- The length of non-crack-type flaws in Zone I (quality grade) of welded joint was limited;
- The overall programming structure involving ultrasonic testing of welded joints was adjusted. The ultrasonic testing of fillet joint between nozzle and cylinder (head), ultrasonic testing of T-type welded joint, ultrasonic testing and quality grading of welding overlay were placed in the appendix;
- "ultrasonic testing method for thickness of pressure equipment" was added according to actual demand of testing, including the measurement method for stainless steel overlay thickness;
- As for ultrasonic testing of the pressure equipment in-service, selection of ultrasonic testing technique, testing position and testing ratio based on such factors as the possible failure modes of main materials, spare parts or welded joints during operation, or the risk assessment results were added.
This Part was proposed and is under the jurisdiction of the National Technical Committee on Boilers and Pressure Vessels of Standardization Administration of China (SAC/TC 262).
Drafting organizations of this Part: Hefei General Machinery Research Institute, China Special Equipment Inspection and Research Institute, Shanghai Electric Nuclear Power Equipment Co., Ltd., Dalian Hydrogenation Reactor Manufacturing Co., Ltd. of China First Heavy Industries, Special Equipment Safety Supervision Inspection Institute of Jiangsu Province, Lanzhou LS Heavy Equipment Co., Ltd.
Chief drafters of this Part: Yan Changzhou, Zheng Hui, Xu Zunyan, Zhou Fengge, Zhou Yufeng, Tao Yuanhong, Zheng Kai, Gu Jie, Zhang Baozhong, Pan Qianghua.
The previous editions of the standard superseded by this Part are:
- JB 4730-1994, JB/T 4730.3-2005.
NATIONAL STANDARD
OF THE PEOPLE’S REPUBLIC OF CHINA
中华人民共和国能源行业标准
NB/T 47013.3-2015
Supersedes JB/T 4730.3-2005
Nondestructive Testing of Pressure Equipments
- Part 3: Ultrasonic Testing
承压设备无损检测
第3部分：超声检测
1 Scope
1.1 This Part of NB/T 47013 specifies the ultrasonic testing methods and quality grading requirements for workpiece flaws of pressure equipment by Type A pulse-echo ultrasonic testing instrument.
1.2 This Part is applicable to the ultrasonic testing of raw materials or spare parts and welded joints of metal pressure equipment, as well as the metal pressure equipment in-service.
1.3 This Part specifies the ultrasonic measurement methods for the thickness of pressure equipment.
1.4 The ultrasonic testing of the supporting and structural members related to the pressure equipment may also make reference to this Part.
2 Normative References
The following documents for the application of this document are essential. Any dated reference, just dated edition applies to this document. For undated references, the latest edition (including any amendments) applies to this document.
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 - General Specification for Ultrasonic Test Block
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 Equipments - Part 1: General Requirements
3 Terms and Definitions
For the purpose of this Part, the terms and definitions in GB/T 12604.1 and NB/T 47013.1 as well as the following ones apply.
3.1
Reduction of backwall echo caused by the presence of discontinuities BG/BF
The ratio of the first bottom echo amplitude BG in the good area near the flaw area to the first bottom echo amplitude BF in the flaw area when testing the forgings. It is expressed by dB.
3.2
Grouped discontinuities
When testing the forgings, there are five or more flaw reflection signals within the range equal to 50mm sound path at the scanning line on display screen; or five or more flaw reflection signals are found within the same depth range on 50mm×50mm testing surface; their reflected wave amplitudes are greater than or equal to the flaw of a specific equivalent of flat-bottom pore diameter.
3.3
Reference sensitivity
The sensitivity of regulating the artificial reflector echo height of reference block or the bottom echo height of tested workpiece to some certain benchmark.
3.4
Scanning sensitivity
The sensitivity of actual testing by properly improving dB (gain) based on reference sensitivity and according to the surface condition, flaw testing requirements, probe type, etc.
3.5
Through thickness dimension of the flaw (flaw height)
Dimension of flaw at the direction of workpiece thickness.
3.6
Echo dynamic patterns
The envelope line of probe movement distance and the echo amplitude variation of corresponding flaw reflector.
3.7
Base material nominal thicknesses (workpiece thickness)/t
Workpiece thickness is defined as follows:
a) As for plate welded joints, if the base material thicknesses at both sides of weld are the same, t is the nominal thickness of base material; if not, t is the nominal thickness of the thinner side of the base material;
b) As for insert-type nozzle fillet joint, t is the nominal thickness of cylinder or head; as for abutting-type fillet joint between nozzle and cylinder (or head), t is the nominal thickness of nozzle;
c) As for T-type welded joint, t is the nominal thickness of web.
4 General Requirements
4.1 Testing personnel
4.1.1 The general requirements for ultrasonic testing personnel shall meet the relevant requirements of NB/T 47013.1.
4.1.2 Ultrasonic testing personnel shall have the basic knowledge of metal materials, equipment manufacture and installation, welding and heat treatment, etc., shall be familiar with the materials, geometric dimension, sonolucency and the like of the tested workpieces, and be able to analyze, judge and handle the problems occurring during test.
4.2 Testing apparatus and equipment
4.2.1 Product quality certificates of instrument and probe
The ultrasonic testing instrument quality certificate shall give out at least the following main performance parameters: preheating time, low voltage for alarming and automatic shutdown, transmitted pulse repetition frequency, effective output impedance, transmitted pulse voltage, transmitted pulse rise time, transmitted pulse width (where square-wave pulse is transmitted), frequency band of receiving circuit, etc. The probe quality certificate shall give out the main parameters such as center frequency, bandwidth, impedance or static capacitance, relative pulse echo sensitivity, angle probe sound beam performance (including front distance of probe (incidence point), K value (refraction angle β), etc.) etc.
4.2.2 Testing instrument, probe and combination performance
4.2.2.1 Testing instrument
Type A pulse-echo ultrasonic testing instrument is adopted, of which the operating frequency shall at least cover the range of 0.5MHz~10MHz when measured by -3dB. The testing conditions and index requirements of its performance shall meet the requirements of Appendix A and documentation shall be provided. The testing methods meet those specified in GB/T 27664.1.
4.2.2.2 Probe
Generally, the diameter of round wafer and every side of square wafer shall not be larger than 40mm. Their performance indexes shall meet the requirements of Appendix B and documentation shall be provided. The testing methods meet those specified in GB/T 27664.2.
4.2.2.3 Combination performance of instrument and probe
4.2.2.3.1 Combination performance of instrument and probe includes horizontal linearity, vertical linearity, combination frequency, surplus sensitivity, dead zone (normal probe only) and far-field resolution.
4.2.2.3.2 The combination performance of instrument and probe shall be measured under the following circumstances:
a) The newly-purchased ultrasonic testing instrument and (or) probe;
b) The main components of instrument and probe are repaired or replaced;
c) Where the testing personnel have doubts.
4.2.2.3.3 The horizontal linearity deviation is not greater than 1% and the vertical linearity deviation is not greater than 5%.
4.2.2.3.4 The deviation between the instrument-probe combination frequency and the nominal frequency of probe shall not be greater than ±10%.
4.2.2.3.5 Instrument-normal probe combination performance shall also meet the following requirements:
a) The surplus sensitivity shall not be less than 32dB;
b) Under reference sensitivity, as for probe with nominal frequency of 5MHz, the dead zone is not larger than 10mm; as for probe with nominal frequency of 2.5MHz, the dead zone is not larger than 15mm;
c) The far-field resolution of normal probe is not less than 20dB.
4.2.2.3.6 Instrument-angle probe combination performance shall also meet the following requirements:
a) The surplus sensitivity shall not be less than 42dB;
b) The far-field resolution of angle probe is not less than 12dB.
4.2.2.3.7 Where the maximum testing sound path of the tested workpiece is reached, the effective sensitivity surplus shall not be less than 10dB.
4.2.2.3.8 The instrument-probe combination frequency is tested according to the methods specified in JB/T 10062; the testing methods for other combination performance refer to JB/T 9214.
4.2.3 Test block
4.2.3.1 Standard test block
4.2.3.1.1 Standard test block refers to the material block possessed of specified chemical compositions, surface roughness, heat treatment and geometrical shape, and used to assess and calibrate the ultrasonic testing equipment, i.e. the test block used to calibrate the performance of instrument and probe system. The standard test blocks adopted herein are CSK-IA, DZ-I and DB-P Z20-2 made from No.20 high-quality carbon structural steel.
4.2.3.1.2 The specific shape and dimension of CSK-IA test block are detailed in this Part, and that of DZ-I and DB-P Z20-2 are detailed in JB/T 9214.
4.2.3.1.3 The manufacture of standard test block shall meet the requirements of JB/T 8428. The manufacturer shall provide product quality certificate and ensure that the maximum reflected wave amplitude difference shall be less than or equal to 2dB by comparing the same reflectors (surfaces) of every standard test block it produces and the national standard sample or the standard test block with similar quantity transmission reference under the same testing conditions.
4.2.3.2 Reference block
4.2.3.2.1 Reference block refers to the one similar to the tested piece, of similar chemical composition in materials with the tested piece, containing definite reference reflector (reflector shall be manufactured by machining process), and used to regulate the amplitude and sound path of ultrasonic testing equipment to compare the detected flaw signal with the signal phase generated by the known reflector, i.e. the test block used for testing and calibration.
4.2.3.2.2 The overall dimension of reference block shall be able to represent the characteristics of the tested workpiece. The thickness of test block shall be the same with that of the tested workpiece. Where the butt joint between different-thickness workpieces is tested, the thickness of test block shall adopt the thicker one.
4.2.3.2.3 The reference block shall be made of materials having the same or similar acoustic performance with the tested materials. Where normal probe is adopted for testing, there shall be no flaw larger than or equal to the equivalent diameter of Φ2mm flat bottom hole.
4.2.3.2.4 The shape, dimension and quantity of artificial reflectors of the reference blocks used for ultrasonic testing of different tested workpieces shall meet the requirements of relevant chapters in this Part.
4.2.3.2.5 If the dimension accuracy of reference block is specified in this Part, the corresponding documentation shall be provided; if not, refer to the requirements of JB/T 8428.
4.2.4 Couplant
4.2.4.1 The couplant shall be of good sonolucency and shall not damage the testing surface, such as engine oil, chemical paste, glycerin, water.
4.2.4.2 Control of contaminant content in couplant
4.2.4.2.1 The sulfur content in the couplant used on nickel base alloy shall not be greater than 250mg/L.
4.2.4.2.2 The total content of halogen (chlorine and fluorine) in couplant used on austenitic stainless steel or titaniumtim shall not be greater than 250mg/L.
4.2.5 Calibration, checking, operation checking or inspection requirements for ultrasonic testing equipment and apparatus
4.2.5.1 The calibration, checking and operation checking shall be conducted on the standard test block. The main sound beam of probe shall be made vertical to the reflecting surface of the reflector so as to obtain stability and the maximum reflected signal.
4.2.5.2 Calibration or checking
4.2.5.2.1 The ultrasonic instrument-probe combination performances, such as horizontal linearity, vertical linearity, combination frequency, dead zone (normal probe only), surplus sensitivity, resolution and attenuator accuracy of the instrument are calibrated and recorded at least once a year. The testing requirements shall comply with those specified in 4.2.2.3.
4.2.5.2.2 The surface corrosion and mechanical damage of standard test block and reference block are checked at least once a year.
4.2.5.3 Operation checking
4.2.5.3.1 At least the horizontal linearity and vertical linearity among the instrument-probe combination performances shall be checked and recorded every 3 months for analog ultrasonic testing instrument and every 6 months for digital ultrasonic testing instrument. The testing requirements shall comply with those specified in 4.2.2.3.
4.2.5.3.2 At least the dead zone (normal probe only), surplus sensitivity and resolution shall be checked and recorded every 3 months. The testing requirements shall comply with those specified in 4.2.2.3.
4.2.5.4 Inspection
4.2.5.4.1 Before each testing, the appearance, cable connection and start-up signal display shall be inspected to judge if they are normal.
4.2.5.4.2 Where angle probe is adopted, the incidence point (front distance) and refraction angle (K value) shall be determined before testing.
4.2.5.5 Precautions of calibration, operation checking and inspection
During calibration, operation checking and inspection, the controllers (e.g. suppression switch or filter switch) affecting the instrument linearity shall be placed at "off" positon or at the lowest level.
Contents Foreword i 1 Scope 2 Normative References 3 Terms and Definitions 4 General Requirements 5 Ultrasonic Testing Method and Quality Grading of Raw Materials or Spare Parts for Pressure Equipment 6 Ultrasonic Testing Method and Quality Grading of Welded Joint for Pressure Equipment 7 Ultrasonic Testing Method for Pressure Equipment Thickness 8 Ultrasonic Testing Method for Pressure Equipment In-service 9 Ultrasonic Testing Record and Report Appendix A (Normative) Requirements for Electrical Performance Index of Ultrasonic Testing Instrument Appendix B (Normative) Performance Index Requirements of Probe for Ultrasonic Testing Appendix C (Normative) Performance Requirements of Double Crystal Normal Probe Appendix D (Normative) Ultrasonic Angle Probe Testing Method and Acceptance Standard of Plates for Pressure Equipment Appendix E (Normative) Ultrasonic Angle Probe Testing Method and Quality Grading of Steel Forgings for Pressure Equipment Appendix F (Normative) Ultrasonic Angle Probe Testing Method of Austenite Steel Forgings for Pressure Equipment Appendix G (Normative) Ultrasonic Testing Method and Quality Grading of Welding Overlay for Pressure Equipment Appendix H (Normative) Ultrasonic Testing Method and Quality Grading of Butt Joint for Aluminum, Aluminum Alloy and Titanium Pressure Equipment Appendix I (Informative) Ultrasonic Testing Method and Quality Grading of Austenitic Stainless Steel Butt Joints Appendix J (Normative) Ultrasonic Testing Method for Longitudinal Butt Joints on Curved Surface of Pressure Equipment Appendix K (Normative) Ultrasonic Testing Method for Circumferential Butt Joints on Curved Surface of Pressure Equipment Appendix L (Normative) Ultrasonic Testing Method for Fillet Joint between the Nozzle of Pressure Equipment and Cylinder (or Head) Appendix M (Normative) Ultrasonic Testing Methods for T-shaped Welded Joint Appendix N (Normative) Specific Requirements for Ultrasonic Testing of Different Types of Welded Joints Appendix O (Normative) CSK-IIIA Test Block Appendix P (Normative) Determination of Sound Energy Transmission Loss Difference Appendix Q (Normative) Echo Dynamic Pattern Appendix R (Normative) Flaw Height Measurement (I) – Flaw Height Measurement by Tip Diffraction Wave Method Appendix S (Normative) Flaw Height Measurement (II) - Flaw Height Measurement by Maximum Tip Echo Method Appendix T (Normative) Flaw Height Measurement (III) – Flaw Height Measurement by -6dB Method
NB/T 47013.3-2015, NB 47013.3-2015, NBT 47013.3-2015, NB/T47013.3-2015, NB/T 47013.3, NB/T47013.3, NB47013.3-2015, NB 47013.3, NB47013.3, NBT47013.3-2015, NBT 47013.3, NBT47013.3
Introduction of NB/T 47013.3-2015
Codeofchina.com is in charge of this English translation. In case of any doubt about the English translation, the Chinese original shall be considered authoritative.
This Standard "Nondestructive Testing of Pressure Equipments" (NB/T 47013) comprises 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 4: Sound Emission Testing;
- Part 10: Ultrasonic Time of Flight Diffraction Technique;
- Part 11: X-ray Digital Radioscopic Testing;
- Part 12: Magnetic Flux Leakage Testing;
- Part 13: Pulsed Eddy Current Testing.
This part is Part 3 of NB/T 47013: Ultrasonic Testing.
This Part was drafted according to the rules given in "Directives for Standardization - Part 1: Structure and Drafting of Standards" (GB/T 1.1-2009).
This Part supersedes "Nondestructive Testing of Pressure Equipments - Part 3: Ultrasonic Testing" (JB/T 4730.3-2005). Compared with JB/T 4730.3-2005, this Part has the following main technical changes:
- "Terms and Definitions" was added, including the terms and definitions concerning ultrasonic testing in the former JB/T 4730.1;
- "Commonly Used Specification for A-mode Ultrasonic Flaw Detector Using Pulse Echo Technique" (JB/T 10061) was superseded by "Non-destructive Testing - Characterization and Verification of Ultrasonic Test Equipment - Part 1: instruments" (GB/T 27664.1), and more scientific requirements for the performance of ultrasonic testing equipment were proposed;
- The specific performance indexes of ultrasonic testing instrument and probe were added;
- Requirements for probe calibration, checking, operation checking and inspection of ultrasonic testing instrument and probe were added;
- "Safety Requirements" was added, proposing safety requirements for the personnel during ultrasonic testing;
- The requirements of process documents were added and relevant factors regarding process specification were listed;
- The types of test blocks (standard test block and reference block) used in this Part were re-defined mainly according to the requirements of relevant general standards in China instead of defining the types of standard test blocks and reference blocks in this Part separately;
- The contents order of "ultrasonic testing method and quality grading of raw materials or spare parts for the pressure equipment" was adjusted to plate, clad plate, carbon and low-alloy steel forging, steel bolt blank, austenitic steel forging and seamless steel pipe, etc.;
- The ultrasonic testing methods and quality grading of carbon steel and low-alloy steel plates, aluminium and aluminium alloy plates, titanium and titanium alloy plates, nickel and nickel alloy plates, as well as austenitic stainless steel and duplex stainless steel plates were merged. Reference block was redesigned. The testing sensitivity was mainly determined according to the distance amplitude curve of flat bottom hole of reference block. The requirements of quality grades were modified and the acceptable indexes of all grades were stricter. In JB/T 4730.3-2005, the requirements of quality grades of plates were lower, and insufficient to control the quality any more. Moreover, there existed a large gap from the specific indexes of relevant quality requirements in ISO, EN standards. Therefore, the quality grading was modified by reference to EN standards, etc.;
- Two Chapters of 2005 Edition "ultrasonic testing and quality grading for butt joint of the pressure equipment" and "ultrasonic testing and quality grading for circumferential butt joint of pipes and pressure pipeline of the pressure equipment" were integrated. Grading was made according to the welded joint type, workpiece thickness and curvature of testing surface, etc.;
- The applicable workpiece thickness of welded joint of pressure equipment expanded from 8mm~400mm to 6mm~500mm;
- The position and quantity of artificial reflector on CSK-IIA and CSK-IVA test blocks were redesigned. This not only guarantees the coverage over the testing area, but also applies to the regulation of reference sensitivity of normal probe. New CSK-IIA test block is applicable to workpiece thickness of 6mm~200mm by mainly reference to EN and JIS standards; new CSK-IVA test block is applicable to workpiece thickness larger than 200mm~500mm by making improvement mainly based on ASME codes. The artificial reflector diameters of test blocks were unified to Φ6mm;
- Ultrasonic testing requirements for different types of welded joints were further detailed, including plate welded joint, T-type welded joint, insert-type nozzle fillet joint, L-type welded joint, fillet joint between abutting nozzle and cylinder (or head), cruciform joint, butt joint between embedded nozzle and cylinder (or head), etc.;
- GS test block was redesigned. Arc reflecting surface and others were added, which is mainly beneficial to the time baseline adjustment of cambered surface probe;
- The length of non-crack-type flaws in Zone I (quality grade) of welded joint was limited;
- The overall programming structure involving ultrasonic testing of welded joints was adjusted. The ultrasonic testing of fillet joint between nozzle and cylinder (head), ultrasonic testing of T-type welded joint, ultrasonic testing and quality grading of welding overlay were placed in the appendix;
- "ultrasonic testing method for thickness of pressure equipment" was added according to actual demand of testing, including the measurement method for stainless steel overlay thickness;
- As for ultrasonic testing of the pressure equipment in-service, selection of ultrasonic testing technique, testing position and testing ratio based on such factors as the possible failure modes of main materials, spare parts or welded joints during operation, or the risk assessment results were added.
This Part was proposed and is under the jurisdiction of the National Technical Committee on Boilers and Pressure Vessels of Standardization Administration of China (SAC/TC 262).
Drafting organizations of this Part: Hefei General Machinery Research Institute, China Special Equipment Inspection and Research Institute, Shanghai Electric Nuclear Power Equipment Co., Ltd., Dalian Hydrogenation Reactor Manufacturing Co., Ltd. of China First Heavy Industries, Special Equipment Safety Supervision Inspection Institute of Jiangsu Province, Lanzhou LS Heavy Equipment Co., Ltd.
Chief drafters of this Part: Yan Changzhou, Zheng Hui, Xu Zunyan, Zhou Fengge, Zhou Yufeng, Tao Yuanhong, Zheng Kai, Gu Jie, Zhang Baozhong, Pan Qianghua.
The previous editions of the standard superseded by this Part are:
- JB 4730-1994, JB/T 4730.3-2005.
NATIONAL STANDARD
OF THE PEOPLE’S REPUBLIC OF CHINA
中华人民共和国能源行业标准
NB/T 47013.3-2015
Supersedes JB/T 4730.3-2005
Nondestructive Testing of Pressure Equipments
- Part 3: Ultrasonic Testing
承压设备无损检测
第3部分：超声检测
1 Scope
1.1 This Part of NB/T 47013 specifies the ultrasonic testing methods and quality grading requirements for workpiece flaws of pressure equipment by Type A pulse-echo ultrasonic testing instrument.
1.2 This Part is applicable to the ultrasonic testing of raw materials or spare parts and welded joints of metal pressure equipment, as well as the metal pressure equipment in-service.
1.3 This Part specifies the ultrasonic measurement methods for the thickness of pressure equipment.
1.4 The ultrasonic testing of the supporting and structural members related to the pressure equipment may also make reference to this Part.
2 Normative References
The following documents for the application of this document are essential. Any dated reference, just dated edition applies to this document. For undated references, the latest edition (including any amendments) applies to this document.
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 - General Specification for Ultrasonic Test Block
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 Equipments - Part 1: General Requirements
3 Terms and Definitions
For the purpose of this Part, the terms and definitions in GB/T 12604.1 and NB/T 47013.1 as well as the following ones apply.
3.1
Reduction of backwall echo caused by the presence of discontinuities BG/BF
The ratio of the first bottom echo amplitude BG in the good area near the flaw area to the first bottom echo amplitude BF in the flaw area when testing the forgings. It is expressed by dB.
3.2
Grouped discontinuities
When testing the forgings, there are five or more flaw reflection signals within the range equal to 50mm sound path at the scanning line on display screen; or five or more flaw reflection signals are found within the same depth range on 50mm×50mm testing surface; their reflected wave amplitudes are greater than or equal to the flaw of a specific equivalent of flat-bottom pore diameter.
3.3
Reference sensitivity
The sensitivity of regulating the artificial reflector echo height of reference block or the bottom echo height of tested workpiece to some certain benchmark.
3.4
Scanning sensitivity
The sensitivity of actual testing by properly improving dB (gain) based on reference sensitivity and according to the surface condition, flaw testing requirements, probe type, etc.
3.5
Through thickness dimension of the flaw (flaw height)
Dimension of flaw at the direction of workpiece thickness.
3.6
Echo dynamic patterns
The envelope line of probe movement distance and the echo amplitude variation of corresponding flaw reflector.
3.7
Base material nominal thicknesses (workpiece thickness)/t
Workpiece thickness is defined as follows:
a) As for plate welded joints, if the base material thicknesses at both sides of weld are the same, t is the nominal thickness of base material; if not, t is the nominal thickness of the thinner side of the base material;
b) As for insert-type nozzle fillet joint, t is the nominal thickness of cylinder or head; as for abutting-type fillet joint between nozzle and cylinder (or head), t is the nominal thickness of nozzle;
c) As for T-type welded joint, t is the nominal thickness of web.
4 General Requirements
4.1 Testing personnel
4.1.1 The general requirements for ultrasonic testing personnel shall meet the relevant requirements of NB/T 47013.1.
4.1.2 Ultrasonic testing personnel shall have the basic knowledge of metal materials, equipment manufacture and installation, welding and heat treatment, etc., shall be familiar with the materials, geometric dimension, sonolucency and the like of the tested workpieces, and be able to analyze, judge and handle the problems occurring during test.
4.2 Testing apparatus and equipment
4.2.1 Product quality certificates of instrument and probe
The ultrasonic testing instrument quality certificate shall give out at least the following main performance parameters: preheating time, low voltage for alarming and automatic shutdown, transmitted pulse repetition frequency, effective output impedance, transmitted pulse voltage, transmitted pulse rise time, transmitted pulse width (where square-wave pulse is transmitted), frequency band of receiving circuit, etc. The probe quality certificate shall give out the main parameters such as center frequency, bandwidth, impedance or static capacitance, relative pulse echo sensitivity, angle probe sound beam performance (including front distance of probe (incidence point), K value (refraction angle β), etc.) etc.
4.2.2 Testing instrument, probe and combination performance
4.2.2.1 Testing instrument
Type A pulse-echo ultrasonic testing instrument is adopted, of which the operating frequency shall at least cover the range of 0.5MHz~10MHz when measured by -3dB. The testing conditions and index requirements of its performance shall meet the requirements of Appendix A and documentation shall be provided. The testing methods meet those specified in GB/T 27664.1.
4.2.2.2 Probe
Generally, the diameter of round wafer and every side of square wafer shall not be larger than 40mm. Their performance indexes shall meet the requirements of Appendix B and documentation shall be provided. The testing methods meet those specified in GB/T 27664.2.
4.2.2.3 Combination performance of instrument and probe
4.2.2.3.1 Combination performance of instrument and probe includes horizontal linearity, vertical linearity, combination frequency, surplus sensitivity, dead zone (normal probe only) and far-field resolution.
4.2.2.3.2 The combination performance of instrument and probe shall be measured under the following circumstances:
a) The newly-purchased ultrasonic testing instrument and (or) probe;
b) The main components of instrument and probe are repaired or replaced;
c) Where the testing personnel have doubts.
4.2.2.3.3 The horizontal linearity deviation is not greater than 1% and the vertical linearity deviation is not greater than 5%.
4.2.2.3.4 The deviation between the instrument-probe combination frequency and the nominal frequency of probe shall not be greater than ±10%.
4.2.2.3.5 Instrument-normal probe combination performance shall also meet the following requirements:
a) The surplus sensitivity shall not be less than 32dB;
b) Under reference sensitivity, as for probe with nominal frequency of 5MHz, the dead zone is not larger than 10mm; as for probe with nominal frequency of 2.5MHz, the dead zone is not larger than 15mm;
c) The far-field resolution of normal probe is not less than 20dB.
4.2.2.3.6 Instrument-angle probe combination performance shall also meet the following requirements:
a) The surplus sensitivity shall not be less than 42dB;
b) The far-field resolution of angle probe is not less than 12dB.
4.2.2.3.7 Where the maximum testing sound path of the tested workpiece is reached, the effective sensitivity surplus shall not be less than 10dB.
4.2.2.3.8 The instrument-probe combination frequency is tested according to the methods specified in JB/T 10062; the testing methods for other combination performance refer to JB/T 9214.
4.2.3 Test block
4.2.3.1 Standard test block
4.2.3.1.1 Standard test block refers to the material block possessed of specified chemical compositions, surface roughness, heat treatment and geometrical shape, and used to assess and calibrate the ultrasonic testing equipment, i.e. the test block used to calibrate the performance of instrument and probe system. The standard test blocks adopted herein are CSK-IA, DZ-I and DB-P Z20-2 made from No.20 high-quality carbon structural steel.
4.2.3.1.2 The specific shape and dimension of CSK-IA test block are detailed in this Part, and that of DZ-I and DB-P Z20-2 are detailed in JB/T 9214.
4.2.3.1.3 The manufacture of standard test block shall meet the requirements of JB/T 8428. The manufacturer shall provide product quality certificate and ensure that the maximum reflected wave amplitude difference shall be less than or equal to 2dB by comparing the same reflectors (surfaces) of every standard test block it produces and the national standard sample or the standard test block with similar quantity transmission reference under the same testing conditions.
4.2.3.2 Reference block
4.2.3.2.1 Reference block refers to the one similar to the tested piece, of similar chemical composition in materials with the tested piece, containing definite reference reflector (reflector shall be manufactured by machining process), and used to regulate the amplitude and sound path of ultrasonic testing equipment to compare the detected flaw signal with the signal phase generated by the known reflector, i.e. the test block used for testing and calibration.
4.2.3.2.2 The overall dimension of reference block shall be able to represent the characteristics of the tested workpiece. The thickness of test block shall be the same with that of the tested workpiece. Where the butt joint between different-thickness workpieces is tested, the thickness of test block shall adopt the thicker one.
4.2.3.2.3 The reference block shall be made of materials having the same or similar acoustic performance with the tested materials. Where normal probe is adopted for testing, there shall be no flaw larger than or equal to the equivalent diameter of Φ2mm flat bottom hole.
4.2.3.2.4 The shape, dimension and quantity of artificial reflectors of the reference blocks used for ultrasonic testing of different tested workpieces shall meet the requirements of relevant chapters in this Part.
4.2.3.2.5 If the dimension accuracy of reference block is specified in this Part, the corresponding documentation shall be provided; if not, refer to the requirements of JB/T 8428.
4.2.4 Couplant
4.2.4.1 The couplant shall be of good sonolucency and shall not damage the testing surface, such as engine oil, chemical paste, glycerin, water.
4.2.4.2 Control of contaminant content in couplant
4.2.4.2.1 The sulfur content in the couplant used on nickel base alloy shall not be greater than 250mg/L.
4.2.4.2.2 The total content of halogen (chlorine and fluorine) in couplant used on austenitic stainless steel or titaniumtim shall not be greater than 250mg/L.
4.2.5 Calibration, checking, operation checking or inspection requirements for ultrasonic testing equipment and apparatus
4.2.5.1 The calibration, checking and operation checking shall be conducted on the standard test block. The main sound beam of probe shall be made vertical to the reflecting surface of the reflector so as to obtain stability and the maximum reflected signal.
4.2.5.2 Calibration or checking
4.2.5.2.1 The ultrasonic instrument-probe combination performances, such as horizontal linearity, vertical linearity, combination frequency, dead zone (normal probe only), surplus sensitivity, resolution and attenuator accuracy of the instrument are calibrated and recorded at least once a year. The testing requirements shall comply with those specified in 4.2.2.3.
4.2.5.2.2 The surface corrosion and mechanical damage of standard test block and reference block are checked at least once a year.
4.2.5.3 Operation checking
4.2.5.3.1 At least the horizontal linearity and vertical linearity among the instrument-probe combination performances shall be checked and recorded every 3 months for analog ultrasonic testing instrument and every 6 months for digital ultrasonic testing instrument. The testing requirements shall comply with those specified in 4.2.2.3.
4.2.5.3.2 At least the dead zone (normal probe only), surplus sensitivity and resolution shall be checked and recorded every 3 months. The testing requirements shall comply with those specified in 4.2.2.3.
4.2.5.4 Inspection
4.2.5.4.1 Before each testing, the appearance, cable connection and start-up signal display shall be inspected to judge if they are normal.
4.2.5.4.2 Where angle probe is adopted, the incidence point (front distance) and refraction angle (K value) shall be determined before testing.
4.2.5.5 Precautions of calibration, operation checking and inspection
During calibration, operation checking and inspection, the controllers (e.g. suppression switch or filter switch) affecting the instrument linearity shall be placed at "off" positon or at the lowest level.
Contents of NB/T 47013.3-2015
Contents
Foreword i
1 Scope
2 Normative References
3 Terms and Definitions
4 General Requirements
5 Ultrasonic Testing Method and Quality Grading of Raw Materials or Spare Parts for Pressure Equipment
6 Ultrasonic Testing Method and Quality Grading of Welded Joint for Pressure Equipment
7 Ultrasonic Testing Method for Pressure Equipment Thickness
8 Ultrasonic Testing Method for Pressure Equipment In-service
9 Ultrasonic Testing Record and Report
Appendix A (Normative) Requirements for Electrical Performance Index of Ultrasonic Testing Instrument
Appendix B (Normative) Performance Index Requirements of Probe for Ultrasonic Testing
Appendix C (Normative) Performance Requirements of Double Crystal Normal Probe
Appendix D (Normative) Ultrasonic Angle Probe Testing Method and Acceptance Standard of Plates for Pressure Equipment
Appendix E (Normative) Ultrasonic Angle Probe Testing Method and Quality Grading of Steel Forgings for Pressure Equipment
Appendix F (Normative) Ultrasonic Angle Probe Testing Method of Austenite Steel Forgings for Pressure Equipment
Appendix G (Normative) Ultrasonic Testing Method and Quality Grading of Welding Overlay for Pressure Equipment
Appendix H (Normative) Ultrasonic Testing Method and Quality Grading of Butt Joint for Aluminum, Aluminum Alloy and Titanium Pressure Equipment
Appendix I (Informative) Ultrasonic Testing Method and Quality Grading of Austenitic Stainless Steel Butt Joints
Appendix J (Normative) Ultrasonic Testing Method for Longitudinal Butt Joints on Curved Surface of Pressure Equipment
Appendix K (Normative) Ultrasonic Testing Method for Circumferential Butt Joints on Curved Surface of Pressure Equipment
Appendix L (Normative) Ultrasonic Testing Method for Fillet Joint between the Nozzle of Pressure Equipment and Cylinder (or Head)
Appendix M (Normative) Ultrasonic Testing Methods for T-shaped Welded Joint
Appendix N (Normative) Specific Requirements for Ultrasonic Testing of Different Types of Welded Joints
Appendix O (Normative) CSK-IIIA Test Block
Appendix P (Normative) Determination of Sound Energy Transmission Loss Difference
Appendix Q (Normative) Echo Dynamic Pattern
Appendix R (Normative) Flaw Height Measurement (I) – Flaw Height Measurement by Tip Diffraction Wave Method
Appendix S (Normative) Flaw Height Measurement (II) - Flaw Height Measurement by Maximum Tip Echo Method
Appendix T (Normative) Flaw Height Measurement (III) – Flaw Height Measurement by -6dB Method
