The material shown here was part of N. Symond's et. al. paper * presented at the Seventh International Conference on Engineering Failure Analysis ; 3 - 6 July 2016 | The Westin Hotel Leipzig, Germany 1 .
Two marine engine injectors were brought in for inspection after reports of malfunction and poor performance.
Injector B2 was reported to not open even when the pressure was applied at 400bar (normal opening pressure is 280bar). To inspect the component an overview scan was conducted to find potential blockage/stuck mechanism, which was then followed by a higher resolution one to highlight the root of the problem.
Injector A2 was reported to open at 280bar (normal pressure) but was only spraying through 4 holes, with particles of material deposited on the tip. The client also report that there was a fuel leak from the body of item and that the fuel also dribbled from the tip. In this case, the body area of the injector was scanned, to look for a route where fuel could have escaped and this was followed by a higher resolution scan focusing on the tip area to record the position of the debris and its influence on the flow paths within.
* Symonds, N.
University of Southampton, UK
Symonds, N., Mavrogordato, M.N., Katsamenis, O.L., Corni, I., Non-destructive volume imaging in failure analysis: Advantages and applications of x-ray micro-computed tomography (μ-CT), Tuesday 5th July 2016: Breakout Session 5A - Techniques