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1 Translated English of Chinese Standard: GB/T ENERGY INDUSTRY STANDARD OF THE PEOPLE S REPUBLIC OF CHINA NB ICS H 26 GB/T Replacing JB/T Nondestructive Testing of Pressure Equipment Part 5: Penetrant Testing 承压设备无损检测第 5 部分 : 渗透检测 GB/T How to BUY & immediately GET a full-copy of this standard? Search --> Add to Cart --> Checkout (3-steps); 3. No action is required - Full-copy of this standard will be automatically & immediately delivered to your address in 0~60 minutes. 4. Support: Sales@ChineseStandard.net. Wayne, Sales manager Issued on: April 2, 2015 Implemented on: September 1, 2015 Issued by: National Energy Administration Page 1 of 23

2 Table of Contents Foreword Application Scope Normative References Terms and Definitions General Requirements Basic Procedures of Penetrant Testing Operating Method of Penetrant Testing Penetrant Testing of Pressure Equipment in Use Assessment of Testing Results and Quality Grading Testing Records and Reports Annex A (Normative) Diagram of Technological Procedures of Fluorescent and Dye Penetrant Testing Annex B (Normative) Testing Method Used for Non-standard Temperature Page 2 of 23

3 Foreword This Standard NB/T 47013, Nondestructive Testing of Pressure Equipment, is divided into 13 parts: -- Part 1: Nondestructive Testing of Pressure Equipment Part 1: General Requirements; -- Part 2: Nondestructive Testing of Pressure Equipment Part 2: Radiographic Testing; -- Part 3: Nondestructive Testing of Pressure Equipment Part 3: Ultrasonic Testing -- Part 4: Nondestructive Testing of Pressure Equipment Part 4: Magnetic Particle Testing -- Part 5: Nondestructive Testing of Pressure Equipment Part 5: Penetrant Testing -- Part 6: Nondestructive Testing of Pressure Equipment Part 6: Eddy Current Testing -- Part 7: Nondestructive Testing of Pressure Equipment Part 7: Visual Examination -- Part 8: Nondestructive Testing of Pressure Equipment Part 8: Leak Testing -- Part 9: Nondestructive Testing of Pressure Equipment Part 9: Acoustic Emission Testing -- Part 10: Nondestructive Testing of Pressure Equipment Part 10: Ultrasonic Time of Flight Diffraction Technique -- Part 11: Nondestructive Testing of Pressure Equipment Part 11: Standard Practice for X-ray Digital Radiography -- Part 12: Nondestructive Testing of Pressure Equipment Part 12: Magnetic Flux Leakage Testing -- Part 13: Nondestructive Testing of Pressure Equipment Part 13: Pulsed Eddy Current Testing. This Part is Part 5 of NB/T 47013: Penetrant Testing. This Part was drafted in accordance with the rules given in GB/T , Directives for Standardization Part 1: Structure and Drafting of Standards. This Part replaces JB/T , Nondestructive Testing of Pressure Equipment Part 5: Penetrant Testing. Compared with JB/T , the major changes of this Part are as follows: Page 3 of 23

4 Nondestructive Testing of Pressure Equipment Part 5: Penetrant Testing 1 Application Scope This Part of NB/T specifies the liquid penetrant testing method and quality grading of pressure Equipment. This Part applies to the testing of surface-breaking defects which are caused in the manufacture, installation and use of pressure Equipment made of non-porous metallic materials. 2 Normative References The following referenced documents are indispensable for the application of this document. For dated references, only the edition dated applies to this document. For undated references, the latest edition of the referenced documents (including all amendments) applies to this Part. GB 11533, Standard for Logarithmic Visual Acuity Charts GB/T , Non-destructive Testing Terminology Terms Used in Penetrant Testing JB/T 6064, Non-destructive Testing General Specification for Penetrant Blocks JB/T 7523, Non-destructive Testing Materials for Penetrant Testing NB/T , Nondestructive Testing of Pressure Equipment Part 1: General Requirements 3 Terms and Definitions For the purposes of this Part, the following terms and definitions and those defined in GB/T and NB/T apply. 3.1 relevant indication Trace indication formed by penetrant exuded through defects, generally also called defect indication. Page 5 of 23

5 c) calibrate the concentration of bulk penetrant in accordance with the manufacturer s instructions. The calibration method is to inject 10 ml of penetrant to be calibrated and standard penetrant respectively into the measuring cylinders containing 90 ml of colorless kerosene or other inert solvents and mix them up. And then pour the two reagents into chromometer Nessler test tubes to compare colour concentration. If the difference in colour concentration between penetrant to be calibrated and standard penetrant exceeds 20%, then it is unacceptable; d) carry out visual examination for penetrant in use. In case of any obvious turbidity or precipitation, colour change or difficulty to clean, it shall be discarded; e) carry out performance comparison test between all kinds of penetrant blocks and standard penetrant. When the capacity of indicating penetrant to be tested is lower than that of standard penetrant, it shall be discarded; f) the fluorescent brightness of fluorescent penetrant shall not be lower than 75% of the fluorescent brightness of standard penetrant. The test method shall be as specified in JB/T The quality control of developer shall meet the following requirements: a) dry developer shall be examined frequently. In case of powder aggregation, significant residual fluorescence or low performance, it shall be discarded; b) the concentration of wet developer shall be maintained with the working concentration range specified by the manufacturer. Its proportion shall be calibrated frequently; c) in case of turbidity, colour change or difficulty to form a thin and even development layer for wet developer in use, it shall be discarded Penetrant testing agents shall be marked with date of manufacture and shelf life, and accompanied with product certificates and operation instructions For aerosol can penetrant testing agents, the surface of its aerosol can shall be free from rust. The nozzle shall have no leakage Penetrant testing agents shall have good detection performance; they shall not cause corrosion of work pieces and shall be basically non-toxic to human body For nickel base alloy materials, the mass ratio of total content of sulphur shall be less than ; the mass ratio of sulphur element content in the residual after a certain amount of penetrant is evaporated shall not exceed 1%. In case of any higher requirement, it shall be as agreed on by the supplier and the purchaser For austenitic steel, titanium and titanium alloy, the mass ratio of the total content of halogens (chlorides and fluorides) shall be less than ; the mass ratio of the content of chlorine and fluorine elements in the residual after a certain Page 7 of 23

6 l thickness of test block, 3 mm ~ 4 mm. Figure 2 Three Point Test Block of Type B Aluminium alloy test blocks are mainly used in the following two scenarios: a) under the regular service conditions, test whether penetrants can meet the requirements and compare the advantages and disadvantages of two penetrants; b) evaluate penetrant test method at non-standard temperature Chromium-plated test blocks are mainly used to test the systematic sensitivity and operating process correctness of penetrants The test blocks used for dye penetrant testing may not be used in fluorescent penetrant testing, and vice versa If obstruction is found in test blocks or the sensitivity decreases, they shall be repaired or replaced on a timely basis Test blocks shall be rinsed thoroughly with acetone to remove the residual penetrant on test blocks. After rinsing, place test blocks into a closed container containing acetone or mixed liquid of acetone and anhydrous alcohol (of volume mixing ratio 1:1) for immersion for 30 min; store after drying or use other effective methods to store Darkroom or testing field Darkroom or testing field shall be provided with sufficient space and capable of meeting the testing requirements; testing field shall be kept clean; the visible illuminance in a darkroom or dark place during fluorescent testing shall not be greater than 20 lx. 4.3 Technological documents of testing Technological documents of testing include technological procedures and operating instructions Technological procedures shall be as specified in NB/T as well as the specific ranges or requirements of relevant factors listed in Table 2; in case the variations of relevant factors exceed the ranges, technological procedures shall be drafted or revised once again. S.N. 1 Table 2 Relevant Factors Related to Technological Procedures Relevant factors Types and specifications of work pieces to be tested (shape, dimensions, wall thickness and material) 2 Regulations and standards 3 Requirements for testing apparatus and calibration, examination, operation examination or Page 10 of 23

7 Grade A 1 ~ 2 Grade B 2 ~ 3 Grade C Selection of penetrant testing methods The selection of penetrant testing methods shall first meet the requirements of defect types and sensitivity to be tested. Based on this, it may be decided in accordance with the roughness of the surface of work pieces to be tested, the size of batches to be tested and the water source and power supply on the testing field and so on For the work pieces which have bright, clean surface and requires high sensitivity, it is preferable to use the post emulsification dye method and post emulsification fluorescent method, or the solvent-removal fluorescent method may also be used For the work pieces which have rough surface and requires low sensitivity, it is preferable to use water-washable dye method or water-washable fluorescent method For the testing in which there are no water source and power supply on site, it is preferable to use solvent-removal dye method For the testing of large batches of work pieces, it is preferable to use waterwashable dye method or water-washable fluorescent method For the testing of local parts of large work pieces, it is preferable to use solvent-removal dye method or solvent-removal fluorescent method The fluorescent method provides higher testing sensitivity than the dye method. 4.6 Testing period Unless specified otherwise, penetrant testing of welded joints shall be carried out after welding is completed or welding procedure is completed. For the materials having tendency to crack, the penetrant testing of welded joints shall be carried out 24 h at least after welding is finished The penetrant testing of fasteners and forgings shall generally be carried out after the final heat treatment. 5 Basic Procedures of Penetrant Testing 5.1 The basic procedures of penetrant testing are as follows: Page 13 of 23

8 penetrant and the surface roughness of work pieces to be tested. It is generally decided in accordance with the operating instructions of manufacturer and tests. 6.4 Removal of residual penetrant When the tested surface of work pieces is washed to remove residual penetrant, attention shall be drawn to the prevention of over removal and lowering the testing quality. Meanwhile, attention shall be drawn to insufficient removal resulting in the difficulty in the identification of defect indications. When fluorescent penetrant is used, residual penetrant may be observed while removing under the exposure of ultraviolet lamp Both hydrophilic and post emulsification (after emulsification) may be removed using water. During rinsing, the angle between water jetting beam and tested surface is preferably 30 ; the water temperature is 10 C ~ 40 C; unless otherwise specified, the water pressure at the nozzle of rinsing device shall not be greater than 0.34 MPa. When there is no rinsing device, clean and non-shedding cloth may be used to scrub after dipping in water Solvent-removal penetrant is removed using detergent. Except places where it is extremely difficult to wash, first use dry, generally clean and non-shedding cloth to scrub in succession until most of residual penetrant is removed; then use clean nonshedding cloth or paper to scrub by dipping in detergents until the residual penetrant on the tested surface is fully scrubbed. But attention shall be drawn to that the tested surface shall not be scrubbed to-and-fro and shall not be rinsed directly using detergents. 6.5 Drying treatment When dry developer or solvent suspensible developer is applied, the tested surface shall be dried before application; when aqueous developers (water soluble and water suspensible developers) are applied, the tested surface shall be dried after application When auto development is used, drying shall be carried out after washing with water Generally, hot-blast air may be used for drying and natural drying. During drying, the temperature of the tested surface shall not be higher than 50 C. When solventremoval penetrant is used, natural drying shall be carried out at room temperature The drying period is usually 5 min ~ 10 min. 6.6 Application of developer When dry developer is used, first carry out drying treatment, then use an appropriate method to spray developer uniformly on the whole tested surface and maintain for a certain period. The residual developer is removed by knocking lightly or Page 16 of 23

9 than or equal to μw/cm 2. The testing personnel may start fluorescent penetrant testing after they get into the dark area and go through dark adaptation at least for 5 min. The testing personnel shall not wear glasses or filter lens which are detrimental to the testing results Magnifying lens of 5X ~ 10X may be used for the identification of fine indications. Treatment and testing may be carried out once again if necessary. 6.8 Defect indication records Use one or more of the following methods for recording and mark on the sketch at the same time: a) photographing; b) video recording; c) strippable plastic film and so on. 6.9 Retesting In case of any of the following circumstances, retesting needs to be carried out: a) when the testing sensitivity fails to meet requirements, testing with test blocks, after testing is finished; b) when it is found that the operating method in the testing process is incorrect or the technical conditions changes; c) when parties to contract have any dispute, or deem necessary; d) when there is any objection to test results When retesting is decided, the tested surface shall be cleaned thoroughly Post rinsing Carry out post rinsing after testing of work pieces is completed, in order to remove residuals detrimental to future use or materials. 7 Penetrant Testing of Pressure Equipment in Use If high-strength steel and materials sensitive to cracks (including cold crack, heating crack and reheating crack) are used, or if the pressure Equipment in use are used in the environment of corrosive media for a long term where stress corrosion cracking or fatigue cracking may occur, during the penetrant testing of the pressure Equipment in use, the sensitivity grade C shall be used for the testing. Page 18 of 23

10 Annex B (Normative) Testing Method Used for Non-standard Temperature B.1 General When it is impossible to carry out penetrant testing within the temperature range of 5 C ~ 50 C, the testing method shall be evaluated. Aluminium alloy blocks are usually used for evaluation. B.2 Evaluation method B.2.1 Evaluation of penetrant testing method at temperature lower than 5 C After test blocks and all materials used decrease to the target temperature, the lowtemperature testing method to be used is used in Area B. The standard method is used in Area A. Compare the crack indication traces of the two areas, A and B. If the indication traces are basically identical, then the method to be used may be deemed feasible through evaluation. B.2.2 Evaluation of penetrant testing method at temperature higher than 50 C If the testing temperature to be used is higher than 50 C, then test block B needs to be heated and maintained at the temperature during the whole testing process, and the testing method to be used is used in Area B. The standard method is used in Area A. Compare the crack indication traces of the two areas, A and B. If the indication traces are basically identical, then the method to be used may be deemed feasible through evaluation. END Page 23 of 23