When it comes to maintaining efficiency during inspection services, ensuring that materials evaluated are of the same composition as the calibration reference tube is highly important. The properties of materials such as carbon steel change under applied stresses commonly faced in the field, and often result in tubes that have been slightly bent during service, manufacturing, or handling. This can result in false signals erroneously identifying wall loss and cause problems for equipment owners. As a world leader in the NDT industry, Russell’s experts are well-versed in material compensation, and have developed a software solution to deal with these situations.
When it comes to finding a match for calibration samples, it is difficult to find sources that are identical to actual tubes/pipes in both material properties and geometry (thickness, in particular). When the actual tubes/pipes are different than those being calibrated, necessary adjustments must be made to account for these differences The use of programs such as EasyLog makes it possible to do such calibrations for RFT and EC inspections. As compensation require the signal phase for RFT probes in free air and the nominal tube wall area, the values at given frequency can be input via the instrument settings wizard.
The Russell Materials Compensation software allows proper signal phase adjustment for RFT probes used to inspect heat exchanger and boiler tubes. This allows the operator to use calibration tubes that are not an exact match to the tubes in the bundle, and ensures that the predicted defect depths are as close to "ground truth" as possible.
For more information on materials compensation and Russell NDE’s Inspection service, please contact us today.