الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Non-Destructive Testing (NDT), interchangeably known also as Non-Destructive Evaluation or Examination (NDE) ,which use of noninvasive techniques to determine the integrity of a material, component or structure, or quantitatively measure some characteristic of an object , has proven to be a cost saving and beneficial technique to be used in the marine field and oil & gas industry. The Magnetic Flux Leakage (MFL) method is a well-established branch of electromagnetic Non-Destructive Evaluation (NDE) extensively used to assess the physical condition of ferromagnetic structures. The key benefit of inspection by MFL is in being able to cover large areas quickly, providing an alternative to the tedious and sparse ultrasonic spot checks that was a standard practice. Current practice employs MFL to screen the ship hull, tanks, pipeline and piping of marine vessels in addition to screening the floor of storage tanks for potential defects and use the resulting maps to estimate the localized material loss. To provide a more thorough report, MFL scans are supplemented with more detailed ultrasonic spot readings in regions where steel loss has been detected. The reason for this is that MFL signals are “more closely related to volume of metal loss than to the depth of pitting”. This report is concerned with investigating inherent Magnetic Flux Leakage (MFL) technology variables that affect the reliability; repeatability and accurate sizing of defects by using MFL equipment, which uses coils to detect the magnetic flux leakage fields, other than researches which investigate equipment have Hall Effect sensors. External defect sizing factors such as a clean inspection environment are not considered. With such extraneous variables removed, the effects on the MFL signal due to magnetic saturation, the calibration process and of defect geometry can be investigated. The results presented herein confirm that an under-saturated inspection surface is a major limiting factor in defect sizing. Consequently to overcome the limitations presented by under-saturation a new calibration procedure is proposed and investigated. Further suppositions that pertain to defect sizing, due to defect geometry, are also explored and verified empirically.