Training and qualification inspectors for advanced GWT inspections. David Alleyne 7MENDT, Bahrain 14 September 2015

Transcription

1 Training and qualification inspectors for advanced GWT inspections David Alleyne 7MENDT, Bahrain 14 September

2 Presentation Outline Biography History of GWT and inspector training GULT training scheme and recommendations Certification and Qualification process Challenge educate and support inspectors at all levels ISO 17024, 9712 compliant certification Conclusions 2

3 Biography Summary of GUL GUL: Primary function development, design and manufacture of GWT equipment. Guided Ultrasonics Ltd. was set up in 1998/9 to commercialize guided wave inspection systems and train field inspectors. World experts in Guided wave testing of plates and pipe from Imperial College of Science, Technology and Medicine (London, UK). Patent holder for GWT methods. Over 200 man years experience in the guided wave field within GUL, including outstanding academic contributors with widest range of application specific knowledge and expertise. Driver and major contributors for the development of GWT standards, qualification and certification. 3

4 Long range GWT concept Transducer Structure If the guided wave encounters a defect then part of the signal is reflected A single measurement inspects all the material in a long length of the structure End of structure Defect Time, distance 4

5 Results when you just try. Problem (understanding of the physics) involving: - Multiple modes - Multiple directions - Dispersion - Sensitivity to defects varies with modes 5

6 Milestones of GWT Method 1980 s Research Lamb Waves Plate, tubes and spot weld testing application Research and Development Imperial College Development GUL Technology demonstration GUL and oil and gas companies Technology transfer GUL and service companies Understanding, Simulation Software Initial prototype equipment Transduction Electronics Applications Limitations definition Training Support Technology transfer GW community Definition of standards, recommended practices and specifications, certification

7 Dispersion curves for 6 pipe L(0,2) F(1,3) F(2,3) T(0,1) F(1,2) 7

8 Square Cut End FR = 3.7 BW=0 8 inch Sch. 40 8

9 GWT Wavemaker system. Used for range of pipe testing applications Pipe sizes from 1 to 96 Typical test time minutes Internal battery (8 hour life) Automatic testing sequencing and equipment diagnostics Operator recognition (ibutton) 9

10 Amp (Linear) -F2 -F1 +F1 +F2 +F3 +F5 +F4-24dB Angle (deg) Wavemaker result Distance (m) Distance 10

11 Rectangular Defect FR = 3.7 BW=0 8 inch Sch. 40 Weld (3mm Cap height, 12mm length) Defect 172 x 21 x 4mm Height x Axial Length x Depth 11

12 Welded Support FR = 8.8 BW=0 8 inch Sch. 40 Support 100x250x10mm Height x Axial Length x Thickness 12

13 90 degrees Bend FR = 3.8 BW=0 4 inch Sch. 40 Weld (2mm Cap height, 12mm length ) 13

14 Multiple Features FR = 3.7 BW=0 8 inch Sch. 40 Weld (3mm Cap height, 16mm Length, 2mm Root Height, 3mm Root Length) Series of Pits 18 nos x 14mm Diameter x 4mm Depth 14

15 Application Specific Training Many applications are complex and require additional equipment specific training and qualifications Testing of buried pipe Testing of road crossings Process pipwork including bends and pipe fittings Monitoring (gpims) applications 15

16 Certification GUL has pioneered electronic certification using the ibutton system since 2005 Can be remotely updated and revalidated Allows automatic logging of inspector for QA purposes Log of tests is used as proof of experience for advanced qualifications 16

17 Conclusions Improving fundamental understanding through training Properties of waves, interaction with damage and features Environmentally induced affects Historical review of results used to improve accuracy and reduce false calls Monitoring and regular data collection improves understanding of environmental effects Optimisation of inspection (POD) Minimisation of false calls Signal-to-noise ratio (different sources) Variability of sensitivity with frequency and mode New capabilities and technologies Tomography, sizing and monitoring 17