Forum Technical Discussions      Re: flaw checking Posted by: James Boaden    (PID_1262), E-mail: Address, on December 09, 2008 at 17:00 : In Reply to: flaw checking posted by : LANRE ALAPINI , E-mail: Address, on December 09, 2008 at 16:27 : ----------- Start Original Message ----------- : can any body explain the term lack of back wall reflection ------------ End Original Message ------------ Using ultrasonics, a signal is generated that reflects back from the back surface of a component (when generated outside the component some sound reflects off the front surface and some penetrates, this then reflects off the back surface). You should always get reflections from the back surface unless something stops the sound reaching it. Lack of back wall reflection dictates that a defect has stopped the sound reaching the back surface and the area of lack of back surface will be the same as the planar area of the defect. Follow Ups: Post a Followup: Name: E-Mail: Subject: Comments: ----------- Start Original Message ----------- : : can any body explain the term lack of back wall reflection : Using ultrasonics, a signal is generated that reflects back from the back surface of a component (when generated outside the component some sound reflects off the front surface and some penetrates, this then reflects off the back surface). : You should always get reflections from the back surface unless something stops the sound reaching it. Lack of back wall reflection dictates that a defect has stopped the sound reaching the back surface and the area of lack of back surface will be the same as the planar area of the defect. ------------ End Original Message ------------ Optional Link URL: Example: "http://www....html". Alternative write "http://www.ndt.net/wshop/attach/filename.htm" if you transfered a filename.htm via FTP Page Title: is important! Optional Image URL: http://www....gif Attention! Please click the button only once. This may take a moment to process Forum Technical Discussions Help