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1 Case Application Note Weld Inspection of 8 mm 75 mm thickness with Gamma Ir192 Radiation Isotope & Digital Computed Radiography This Case Application report describes the CR Computed Radiographic Image Quality that meets the requirements of ASME Section VIII Division 1 (UW - 51 & UW 52), Division 2 (Al-510 & AI-511), ASME Section 1 (PW - 51), ASME B31.1 ( ), EN444 and EN1435 standards. This computed radiographic image quality is achieved by using an Ir192 radiation isotope. The radiographic image quality is assessed by measuring the contrast sensitivity and the radiographic resolution measured with the geometric unsharpness. The results measured are comparable to those achieved with conventional radiography. Selection of radiographic technique and the radiation source depends on various factors such as: The types of the material that you are inspecting Thickness of the material Types of defects, flaws Radiographic sensitivity required by the referencing code, standards or specifications The cost of radiography Ir192 is one of the most important sources of energy for use in industrial γ-radiography for Non Destructive Testing of metals. Due to its high-energy spectra, it is widely used for thick wall inspection (with CR one can inspect up to 100mms of material thickness). With Computed Radiography it has eliminated the requirement for Co60 radiation sources. The Ir192 gamma source characteristics coupled with the source activity controls the overall quality of the radiographic image. Technical details of the source are as follows: Ir192 Isotope Details Ir 115 Half life d 8 Jπ 4 (+) S π (kev) S p (kev) Prod. Mode Fast neutron activation Thermal neutron activation ENSDF Citation NDS 84, 717 (1998) Literature cut-off date 1-Aug-1998 Author(s) C. M. Baglin References since cut-off 192 Ir decay from (NSR) Decay Properties Mode Branching (%) Q-value (kev) References β Li06 E Li06 For further details of how CITs Digital Radiography Solutions can help YOUR organisation, please contact us at the address below

2 Ir192 Technical Data Conventional Radiography Computed Radiography Gamma-radiation source, isotope,, T 1/2 T 1/2 120 day 74 day 480 day 296 day E, MeV (activity, to Ci) 0,215(120) 0,400 (120) 0,215(120) 0,400 (120) Active core size, mm Thickness of material exposure (Fe), mm. To Ø 3x3 To Ø 4x4 To Ø 3x3 To Ø 4x Transportation and recharging Container (4 channels) Container (4 channels) Overall dimensions of the exposure head (mm) 300x130x x130x270 Mass of exposure head (kg) Ir192 Characteristics Thulium Tm-170 Ytterbium Yb-169 Selenium Iridium Cobalt Co-60 Gamma energy (kev) Half life (days) Gamma constant* Output (radiation nominal dose at 1 meter) 160 µs/h 34 µs/h 130 µs/h 350 µs/h Radiographic Technique Setup Ir192 Radiation Isotope Device SOD 975 mm SFD 1000 mm Weld Plate 25 mm Imaging Plate ODD Lead

3 Test Samples for Ir192 Trials No. Item Description Image 1 CR Phantom 2 14 mm Steel Plate 3 25 mm Steel Plate 4 38 mm Steel Plate 5 52 mm Steel Plate

4 Ir192 Results and Radiographic Image Mentioned below are the Results (with Radiographic Image and Parameters) of the Ir192 trials that have been carried out on different thickness of Steel Plate - Weld Samples and the CR Phantom. Note: The Radiographic Images displayed here are only for illustration purpose. The actual images are of high quality and contain more details. CR Phantom - Parameters & Radiograph Image SFD ( to Ir mm μm Pb 10th Line Pair 10mm Steel Plate - Parameters & Radiograph Image SFD ( to Ir M 10S 1000 mm μm Pb 10th wire on 10FE 0.40 Diameter

5 Note: The Radiographic Images displayed here are only for illustration purpose. The actual images are of high quality and contain more details. 14mm Steel Plate - Parameters & Radiograph Image SFD ( to Ir M 00S 1000 mm μm Pb 6th line pair on Duplex 7th wire on 6FE mm Steel Plate - Parameters & Radiograph Image SFD ( to Ir M 48S 1000 mm μm Pb 6th line pair on Duplex 9th wire on 6FE 0.50

6 Note: The Radiographic Images displayed here are only for illustration purpose. The actual images are of high quality and contain more details. 38mm Steel Plate - Parameters & Radiograph Image SFD ( to Ir M 20S 600 mm μm Pb 9th wire on 6FE th wire on 1B Diameter 52mm Steel Plate - Parameters & Radiograph Image SFD ( to Film Distance) Ir M 54S 600 mm μm Pb 6th wire on 1FE 1.00

7 Note: The Radiographic Images displayed here are only for illustration purpose. The actual images are of high quality and contain more details 75mm Steel Plate - Parameters & Radiograph Image SFD ( to Film Distance) Ir M 00S 450 mm μm Pb Conclusions From the above results it can be seen that, for the range of plate thicknesses tested, acceptable results are achieved by taking 35% of the calculated D4 exposure time as an exposure, achieving required sensitivity and an equivalent radiographic density of 2.0 to 2.9 in the weld. It is provisionally assumed that this relationship will hold for exposures up to and including 75mm (to inspect greater thickness of material radiographic techniques need to be developed).