Eddy Current As Alternate Method for Inspection of Welded Joints
CINDE June 2015
Dave Jankowski (USA) and Dave Perrett (UK)Product Support LeadersGE Inspection Technologies
ND
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anada 2015 Conference, June 15-17, 2015, E
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Inspection of welded joints for surface breaking cracks is required in most
land based and off-shore petro-chemical facilities
Surface breaking cracks can lead to catastrophic failure if undetected and
not repaired
Traditional Weld Inspection MethodsLiquid Penetrant and Magnetic Particle
Advantages
• Reasonable cost
• Portable
• Minimal inspector training
• Easy Interpretation of data
Dis-Advantages
• Coating must be removed prior to inspection then re-applied
• Disposal of chemicals
• Time consuming
• Scaffolding often required
• No digital documentation of indications
EN 1711 (Mar 2000)Eddy Current Examination of Welds by Complex
Plane AnalysisRecently Converted to ISO/DIN 17634 Standard
Other Approvals
• Lloyds Register• DNV (Det Norske Veritas)• Bureau Veritas
EN 1711 (Mar 2000)
EN 1711 (Mar 2000)
EN 1711 (Mar 2000)
EN 1711 (Mar 2000)
EN 1711 (Mar 2000)
LP Inspection Time
Paint Stripping& Cleaning
Penetrant Application &
Dwell
Developer Application &
Dwell
Inspection
Post CleanRepainting
Surface Prep
Inspection
Eddy Current Inspection
Time
2.5 to 3:1LP to EC
LP Inspection Time
Paint Stripping& Cleaning
Penetrant Application &
Dwell
Developer Application &
Dwell
Inspection
Post CleanRepainting
LP/MP Cost
Certified Inspector
Consumables
Capital Equipment
Compliant Disposal of Consumables
EC Cost
$ $$$
None$$$
$ $$$$
None$$$$
LP Versus ECInspection Cost Comparison
Hyperlink to .xls
Penetrant Inspection - 6 off Joints
Task Time Taken (mins) Time/C ost Typical Timings/C osts
Paint removal 40 min s 40 mins
Inspection pre-clean 18 min s 18 mins
Penetrant Application 12 min s 12 mins
Penetrant Dwel l 20 min s 20 mins
Excess Penetrant Removal 18 min s 18 mins
Developer Appl ication 6 min s 6 mins
Developer Dwell 10 min s 10 mins
Evaluation 18 min s 18 mins
Post-clean 18 min s 18 mins
Repainting 20 min s 20 mins
Total Time Take n 3.0 hours 3 hours
Man Hour Rate 24$ US$
Total Man Hour Costs 72$ US$
Consumables, includ ing scaffolding
costs if applicable 60 US$ Min $10/joint
Total Inspe ction Cost 132$ US$
EC Weld Inspection - 6 off Joints
Task Time Taken Time/C ost Typical Timings/C osts
Surface Prep 0.25 hours 15 mins = 0,25 hrs
EC Inspection 1 hours 1 ho ur
Man Hour Rate 60$ US$
Total Inspe ction Cost 75$ US$
SAVI NG U S$ 57$ US$
TIME SAVING 2 hours
Liquid Penetrant Vs. Eddy Current of Welded Jo ints
10" Diame ter P ipe 6 off jo ints inspected
LP Versus ECInspection Cost Comparison
Number of Inspections
Cost
of
Insp
ection
s
Hyperlink to .xls
Middle East 250,000 Barrel Per Day RefineryLP Inspection Costs During Shutdown
~ 10,000 Weld Joints for Cracks
• 500 cans of penetrant aerosols ~ $6,500
• Total Inspection Time: ~5,000 hrs.• ~2,100 hrs. for LP• ~2,900 hrs. for pre and post Inspection tasks
Middle East 250,000 Barrel Per Day RefineryLP Inspection Costs During Shutdown
~ 10,000 Weld Joints for Cracks
• 500 cans of penetrant aerosols ~ $6,500
• Total Inspection Time: ~5,000 hrs.• ~2,100 hrs. for LP• ~2,900 hrs. for pre and post Inspection tasks
Eddy Current: ~1,700 hrs. for entire inspection withno consumables
Eddy Current Inspection of Welds
Field proven EC probe designs minimize impact
of rough surfaces
StandardHigh Wear Ceramic Tip
High Temperature(425F/220C)
Eddy Current Inspection of Welds
Field proven EC probe designs minimize impact
of rough surfaces
StandardHigh Wear Ceramic Tip
High Temperature(425F/220C)
Minimal Lift Off Effect Due to Rough Weld Surface
Eddy Current Inspection of WeldsGuided Workflow Helps Ensure Consistent Inspection and Reduce Error Traps
Digital Documentation of Weld Indications
Collaboration with Remote Experts
CloudServices
ConnectedDevices
WebPortal
More accurate and efficient inspections
Real-time access to knowledge from off-
site experts
Real-time sharing of inspection data
Digital Gain Control (DGC) to Compensate for Varying Coating Thicknesses
As coating/paint thickness varies across a weld, gain automatically readjusted to ensure inspection sensitivity
Summary
• Eddy current is an ISO (EN) approved inspection method for welded joints
• Eddy current offers distinct advantages over LP/MPI
• No consumables to purchase
• No consumables to dispose of
• No need to remove coatings prior to inspection
• Digital record of inspection
• Simple financial analysis can identify break even point for EC inspection compared to LP/MPI
• Guided workflows and remote collaboration can further enhance weld inspections
• Digital Gain Control further improves weld inspection productivity
GE Inspection TechnologiesMentor EM for Weld Inspection