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A D V A N C E D M A T E R I A L S & P R O C E S S E S | S E P T E M B E R 2 0 1 9 2 2 can be manipulated to show porosity, voids, discontinuities, and operational damage, as well as defects, by carefully controlling a set of variables. Variations of imaging plates, films, source strength and size, orientation, distance-to-ob- ject parameters and radiographic setup affect the resulting images and sensi- tivity that can be detected in the com- ponents inspected. The reduction in unwanted attenuation, distortion, re- fraction, and geometric unsharpness directly affect image quality. Adjust- ments are required by experienced NDE inspectors and generator engineers to achieve the necessary image require- ments, and to provide assessment, in- terpretation, and present disposition of findings. Careful control of the many vari- ables can provide informative images. Results can show probable water leak- age paths in degraded water-cooled brazed components and blockages (Fig. 7). The use of radiography, to de- tect cracks and discontinuities in elec- trical conductors (Fig. 8) and loss of integrity (Fig. 9) that can lead to a fail- ure of a component to meet the intend- ed need, can provide an advantage over insulation stripping and visual inspec- tion. Radiographic images provided to engineering and power-plant opera- tors can help to guide risk assessment of continuing to operate equipment without addressing the observed in- dications in the images. The use of ra- diographic inspection can help reduce the potential of equipment failure and correspondingly enhance return on investment. CONCLUSION From the discoveries of Michael Faraday related to electromagnetic induction in the 1830s, to the in- duction-motor inventions of Nikola Tesla in the 1880s, through the entre- preneurial spirit of George Westing- house (1880s–1990s), and Siemens’ continuing innovation, electric power consumption will continue to grow, and that demand can most effectively be met with better energy management, increasing power production, and maintaining the current power base. Radiography can provide an inspection method for keeping electric generators operating reliably. ~AM&P For more information: Jean-Paul Vega, Generator Service Engineering, Siemens Energy, 4400 N Alafaya Trail, Orlando, FL 32826, 980.225.4945, jp.vega@siemens.com. References 1. E. Spiegel and N. McArthur, Energy Shift: Game-Changing Options for Fuel- ing the Future, p 18, 2009. 2. R adiographic Testing Classroom Book, ASNT, p 6, 2016. 3. NRC website, https://www.nrc.gov/ reading-rm/basic-ref/glossary/alara. html. 2019. 4. NRC website, https://www.nrc.gov/ reading-rm/basic-ref/students/science- 101/what-are-different-types-of- radiation.html, 2018. 5. Radiographic Inspection, Nondes- tructive Evaluation and Quality Con- trol , Vol 17, ASM Handbook, ASM Inter- national, p 308, 1997. Fig. 9 — Radiograph showing cracks in water passages. Fig. 7 — Radiograph of water header braze quality showing porosity, voids, and lack of bonding. Fig. 8 — Radiograph showing cracked strands in copper conductors.