JB/T 6902-2008 Methods for liquid penetrant examination of valves
1 Scope
This standard specifies the general requirements for liquid penetrant examination of surface opening defects, penetrant examination methods, and the classification of defect indication severity.
This standard is applicable to the examination of surface opening defects generated during the manufacture, installation and use of valves.
This standard is not applicable to materials with non-surface opening defects and porosity.
2 Normative references
The following normative documents contain provisions which, through reference in this text, constitute provisions of this standard. For dated references, subsequent amendments (excluding corrections) to, or revisions of, any of these publications do not apply to this standard. However parties to agreements based on this standard are encouraged to investigate the possibility of applying the most recent editions of the normative documents indicated below. For undated references, the latest edition of the normative document referred to applies.
GB/T 5097-2005 Non-destructive testing - Penetrant testing and magnetic particle testing - Viewing conditions (ISO 3059:2001, IDT)
GB/T 11533-1989 Standard for logarithmic visual acuity charts
JB/T 6064-2006 Non-destructive testing - Blocks for penetrant testing
JB/T 9213-1999 Non destructive testing - Penetrant testing - A type comparator block
3 General requirements
3.1 Penetrant examination personnel
3.1.1 The penetrant examination personnel shall be those who have certain basic knowledge and penetrant examination experience, and have obtained the technical qualification certificate recognized by the relevant departments through assessment.
3.1.2 The uncorrected and corrected near vision and distant vision of penetrant examination personnel shall not be less than 5.0 (the decimal recorded value is 1.0), and the test method shall meet the requirements of GB/T 11533. The penetrant examination personnel shall be free of color blindness, and shall undergo an annual test.
3.2 Penetrant examination reagent
3.2.1 Control of penetrant
3.2.1.1 Reference penetrant
500 mL shall be taken from each new batch of penetrant and stored in a sealed glass container as a sample for reference benchmark. The sample shall be stored at a temperature of 16℃ to 52℃, and kept from direct sunlight.
3.2.1.2 Penetrant shall be stored in sealed containers in a cool, dark place. The relative density of each penetrant shall be verified with a relative densitometer in accordance with the manufacturer's instructions, and the relative density shall be kept unchanged.
3.2.1.3 The concentration of the penetrant shall be verified frequently as specified in the manufacturer's instructions. The verification method is to inject 10 mL of the penetrant to be verified and 10 mL of the reference penetrant into two graduated cylinders each containing 90 mL of colorless kerosene or other inert solvent, stir evenly. Then place the two reagents separately in Nessler tubes of a colorimeter for color concentration comparison. If the difference in color concentration between the penetrant to be verified and the reference penetrant exceeds 20%, it shall be deemed rejected.
3.2.1.4 Appearance examination of the penetrant being used shall be conducted. If obvious turbidity, sediment, discoloration or difficulty in cleaning is found, the penetrant shall be scrapped.
3.2.1.5 Performance comparison tests shall be carried out for all kinds of penetrants using comparator blocks against the reference penetrant. When the ability of the tested penetrant to show defects is lower than that of the reference penetrant, it shall be scrapped.
3.2.1.6 The fluorescence efficiency of fluorescent penetrants shall not be less than 75%. It shall be tested by the method specified in GB/T 5097.
3.2.2 Quality control requirements for developers
3.2.2.1 Dry developers shall be examined regularly. If powder agglomeration, significant residual fluorescence or performance degradation is found, the developer shall be discarded.
3.2.2.2 The concentration of wet developers shall be maintained within the working range specified by the manufacturer, and its specific gravity shall be verified frequently via a hydrometer.
Contents
Foreword i
1 Scope
2 Normative references
3 General requirements
3.1 Penetrant examination personnel
3.2 Penetrant examination reagent
3.3 Equipment, instruments and test blocks
4 Examination methods
4.1 General requirements
4.2 Examination operating procedure
4.3 Pretreatment
4.4 Penetration treatment
4.5 Emulsification treatment
4.6 Cleaning and removal treatment
4.7 Drying treatment
4.8 Developing treatment
4.9 Observation
4.10 Re-examination
4.11 Post-processing
5 Classification of defect indication severity
6 Examination report
Annex A (Informative) Qualification of penetrant examination methods
A.1 Overview
A.2 Qualification methods
Figure 1 Aluminum alloy test block
Figure 2 Schematic diagram of fluorescent and color penetrant examination process
Figure A.1 Aluminum alloy comparator block
Table 1 Examination method code
Table 2 Developing method code
Table 3 Examination methods
Table 4 Classification of linear defect indications
Table 5 Classification of point-like defect indications
JB/T 6902-2008 Methods for liquid penetrant examination of valves
1 Scope
This standard specifies the general requirements for liquid penetrant examination of surface opening defects, penetrant examination methods, and the classification of defect indication severity.
This standard is applicable to the examination of surface opening defects generated during the manufacture, installation and use of valves.
This standard is not applicable to materials with non-surface opening defects and porosity.
2 Normative references
The following normative documents contain provisions which, through reference in this text, constitute provisions of this standard. For dated references, subsequent amendments (excluding corrections) to, or revisions of, any of these publications do not apply to this standard. However parties to agreements based on this standard are encouraged to investigate the possibility of applying the most recent editions of the normative documents indicated below. For undated references, the latest edition of the normative document referred to applies.
GB/T 5097-2005 Non-destructive testing - Penetrant testing and magnetic particle testing - Viewing conditions (ISO 3059:2001, IDT)
GB/T 11533-1989 Standard for logarithmic visual acuity charts
JB/T 6064-2006 Non-destructive testing - Blocks for penetrant testing
JB/T 9213-1999 Non destructive testing - Penetrant testing - A type comparator block
3 General requirements
3.1 Penetrant examination personnel
3.1.1 The penetrant examination personnel shall be those who have certain basic knowledge and penetrant examination experience, and have obtained the technical qualification certificate recognized by the relevant departments through assessment.
3.1.2 The uncorrected and corrected near vision and distant vision of penetrant examination personnel shall not be less than 5.0 (the decimal recorded value is 1.0), and the test method shall meet the requirements of GB/T 11533. The penetrant examination personnel shall be free of color blindness, and shall undergo an annual test.
3.2 Penetrant examination reagent
3.2.1 Control of penetrant
3.2.1.1 Reference penetrant
500 mL shall be taken from each new batch of penetrant and stored in a sealed glass container as a sample for reference benchmark. The sample shall be stored at a temperature of 16℃ to 52℃, and kept from direct sunlight.
3.2.1.2 Penetrant shall be stored in sealed containers in a cool, dark place. The relative density of each penetrant shall be verified with a relative densitometer in accordance with the manufacturer's instructions, and the relative density shall be kept unchanged.
3.2.1.3 The concentration of the penetrant shall be verified frequently as specified in the manufacturer's instructions. The verification method is to inject 10 mL of the penetrant to be verified and 10 mL of the reference penetrant into two graduated cylinders each containing 90 mL of colorless kerosene or other inert solvent, stir evenly. Then place the two reagents separately in Nessler tubes of a colorimeter for color concentration comparison. If the difference in color concentration between the penetrant to be verified and the reference penetrant exceeds 20%, it shall be deemed rejected.
3.2.1.4 Appearance examination of the penetrant being used shall be conducted. If obvious turbidity, sediment, discoloration or difficulty in cleaning is found, the penetrant shall be scrapped.
3.2.1.5 Performance comparison tests shall be carried out for all kinds of penetrants using comparator blocks against the reference penetrant. When the ability of the tested penetrant to show defects is lower than that of the reference penetrant, it shall be scrapped.
3.2.1.6 The fluorescence efficiency of fluorescent penetrants shall not be less than 75%. It shall be tested by the method specified in GB/T 5097.
3.2.2 Quality control requirements for developers
3.2.2.1 Dry developers shall be examined regularly. If powder agglomeration, significant residual fluorescence or performance degradation is found, the developer shall be discarded.
3.2.2.2 The concentration of wet developers shall be maintained within the working range specified by the manufacturer, and its specific gravity shall be verified frequently via a hydrometer.
Contents of JB/T 6902-2008
Contents
Foreword i
1 Scope
2 Normative references
3 General requirements
3.1 Penetrant examination personnel
3.2 Penetrant examination reagent
3.3 Equipment, instruments and test blocks
4 Examination methods
4.1 General requirements
4.2 Examination operating procedure
4.3 Pretreatment
4.4 Penetration treatment
4.5 Emulsification treatment
4.6 Cleaning and removal treatment
4.7 Drying treatment
4.8 Developing treatment
4.9 Observation
4.10 Re-examination
4.11 Post-processing
5 Classification of defect indication severity
6 Examination report
Annex A (Informative) Qualification of penetrant examination methods
A.1 Overview
A.2 Qualification methods
Figure 1 Aluminum alloy test block
Figure 2 Schematic diagram of fluorescent and color penetrant examination process
Figure A.1 Aluminum alloy comparator block
Table 1 Examination method code
Table 2 Developing method code
Table 3 Examination methods
Table 4 Classification of linear defect indications
Table 5 Classification of point-like defect indications
