Digital image acquisition method for film based radiographic testing

Radiographic Test (RT) has been widely used in various industries to detect inner defects of weld structures and other significant components. In terms of digitization, although the ASME Boiler and Pressure Vessel Code Section V provides general outlines of digital image acquisition and processing of RT film, it is not widely implemented in industries as medical radiography instruments. One major reason for not being able to drive RT film digitization is that they cannot quantitatively guarantee each RT film and its digital image resolution directly. To solve these bottlenecks, the present paper proposes two things: 1) Line pair type penetrameter corresponding to current image quality indicators (IQIs) for both hole and wire type, which enables us to not only easily guarantee radiographic testing film resolution but also quantify digitalized RT film image resolution [1]; and 2) Line pair type standard film which is used for digitizing "existing RT film" with commonly used imaging scanners. Prototypes of line pair type penetrameters have been developed and prepared for various materials and verified for its applicability to RT digitalization. Also, prototypes of standard film are manufactured and verified that used with scanners, we can get RT film images of which resolution are quantitatively guaranteed. These two new RT film digitizing methodologies enable us to get "resolution guaranteed film images" and "digital inspection." Furthermore, this will contribute to "remote inspection" where manufacturers, inspectors, customers and government inspectors can share the results of inspection in electronic format and timely confirm them from a remote place.