The method is especially useful in detecting problems or irregularities in the well such as stuck tools, casing damage, damaged zones in...http://www.google.co.uk/patents/US5081613?utm_source=gb-gplus-sharePatent US5081613 - Method of identification of well damage and downhole irregularitiesAdvanced Patent SearchPublication numberUS5081613 APublication typeGrantApplication numberUS 07/250,036Publi