Engineering Assessment of Engineering Assessment of Fluorescent Penetrant InspectionFluorescent Penetrant Inspection

Lisa BrascheIowa State University515 - 294 - 5227lbrasche@cnde.iastate.edu

Technical Staff:Brian LarsonRick Lopez

ApproachApproach

• Industrial Advisory Board functions including limited data analysis and interpretation

• Generation of guidance materials

• Fabrication of samples• General ISU laboratory

and measurement support

• Performance checks and standards

• Fluorometry devices• Performance verification

kit• Guidance materials• Technology transfer

workshops

Engineering Studies

• Comparison penetrant methods and material effects (4 methods, 3 locations, 150 samples + ISU baseline)

• Peening and compressive stress effects

• Assessment of time/temperature ranges for drying methods on detectability for range of alloys

• Assessment of time/pressure of inspection process parameters on detectability

• Emulsification study• Evaluation procedures• Effect of silicates and other

contaminants

Baseline Program

Engineering Tools

ApproachApproach

• Inspection materials and method• Water washable – level 2 and 3, • Hydrophilic emulsifier – level 3 and 4

• Baseline studies at ISU and industry sites

• POD assessment to be considered

Engineering Studies

• Comparison penetrant methods and material effects (4 methods, 3 locations, 150 samples + ISU baseline)

• Peening and compressive stress effects

• Assessment of time/temperature ranges for drying methods on detectability for range of alloys

• Assessment of time/pressure of inspection process parameters on detectability

• Emulsification study• Evaluation procedures• Effect of silicates and other

contaminants

Materials used (i.e. penetrants, emulsifiers, and developers) shall conform to MIL-I-25135 or AMS 2644 and be listed in QPL 25135 or in QPL-AMS-2644.

ApproachApproachInconel Specimen 00-108 Multi-Crack? No

Optical Length 0.033

pre-run 1 pre-run 2 pre-run 3 Baseline 3 Baseline 4 oven dry 1&3 oven dry 2&4 flash dry 1&3 flash dry 2&4 Baseline 5 Baseline 6Brightness 8.2 5.9 6.3 6.1 9.5 7.8 7.7 7.5 3.8 8.5 4.0Length 0.037 0.035 0.035 0.037 0.037 0.033 0.032 0.035 0.034Dwell Time 2154.0 1415.0 1440.0 1840.0 1225.0 1030.0 2220.0 1325.0

ISU Std Dev Brightness 1.0Length 0.0018

Delta Std Dev Brightness 2.1Length 0.0021

Pre-Delta

ISU Baseline Delta Baseline Delta Drying Study Delta Baselining

Inconel Brightness Group 1

0

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0 2 4 6 8 10 12 14 16

Experiment

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BrightnessLength

ISU Baseline

Delta Baseline

ISU Baseline

Delta Baseline

Delta Drying Study

Oven Flash

Run 1 Run 2 Run 3

ApproachApproach

Engineering Studies

• Comparison penetrant methods and material effects (4 methods, 3 locations, 150 samples + ISU baseline)

• Peening and compressive stress effects

• Assessment of time/temperature ranges for drying methods on detectability for range of alloys

• Assessment of time/pressure of inspection process parameters on detectability

• Emulsification study• Evaluation procedures• Effect of silicates and other

contaminants

• Smearing and compressive stresses imparted by peening can completely eliminate the possibility of penetrant from entering a flaw

• Quantitative assessment of typical industry peening operations will be provided.

• Comparison to mechanical cleaning (PMB, shell, glass bead) will be made.

• Other inspection methods (e.g., eddy current, ultrasonics) will also be assessed for comparison

• Consideration will also be given to other sources of compressive stress and to the extent possible, the stresses measured

• Coordination to prior AF activities regarding compressive stress effects will occur and these studies will build on their prior efforts.

ApproachApproach

Engineering Studies

• Comparison penetrant methods and material effects (4 methods, 3 locations, 150 samples + ISU baseline)

• Peening and compressive stress effects

• Assessment of time/temperature ranges for drying methods on detectability for range of alloys

• Assessment of time/pressure of inspection process parameters on detectability

• Emulsification study• Evaluation procedures• Effect of silicates and other

contaminants

• Review of recent results regarding cleaning and drying studies being performed as part of the ETC Phase II program and CASR team will provide recommendations regarding additional needs in this area.

• Current studies are being performed within the accepted ranges from AMS 2647 rev B.

• Consideration will be given to studies of a range of temperature and time variations to assess their impact on sensitivity.

• Effect of penetrant dwell time, removal wash time, and developer time will be considered using a subset of the samples and data placed in the public domain. This is particularly important given the changes in penetrant chemistry in response to recent environmental changes.

ApproachApproach

Engineering Studies

• Comparison penetrant methods and material effects (4 methods, 3 locations, 150 samples + ISU baseline)

• Peening and compressive stress effects

• Assessment of time/temperature ranges for drying methods on detectability for range of alloys

• Assessment of time/pressure of inspection process parameters on detectability

• Emulsification study• Evaluation procedures• Effect of silicates and other

contaminants

• Common practice involves the use of “bleed-back” processes to assess an indication and make a determination as to whether a defect is present or a false call has occurred.

• Limited data exists that bleed back is not always successful.

• Best practices for bleed-back processes are not available in the public domain and will be assessed and published as part of the program.

ApproachApproach

Engineering Studies

• Comparison penetrant methods and material effects (4 methods, 3 locations, 150 samples + ISU baseline)

• Peening and compressive stress effects

• Assessment of time/temperature ranges for drying methods on detectability for range of alloys

• Assessment of time/pressure of inspection process parameters on detectability

• Emulsification study• Evaluation procedures• Effect of silicates and other

contaminants

• Engineering data for selected factors which affect the sensitivity of FPI, including the presence and effect of silicates on detectability will be provided.

• Quantitative measurements of relevant penetrant system properties using analytical chemistry techniques will be made as necessary.

• Other potential factors to be considered will include:• Penetrant contamination • Emulsifier agitation• Emulsifier bath concentration • Emulsifier contamination, • Developer contamination• Storage temperatures