Preliminary Study of Digital Laminography Parameters on Carbon Steel Plate

Abstract

Laminography is a technique used to determine the depth of a defect in Radiographic Testing (RT). It enables RT operators to accurately locate the defect from the object's surface especially for welded components. The technique will ensure the quality of weld components meets the standard requirement for reliability and safety purposes. This paper intends to study the exposure parameters of laminography technique on carbon steel plate by using Radiographic Testing - Digital. (RT-D). The important exposure parameters that are considered in this preliminary study are voltage, current, and frame time. The radiography images with achievable level of contrast sensitivity and image quality are analyzed according to the ISO 17636-2. Discussion on correlation between the normalized Signal to Noise ratio (SNRN) and the exposure parameters are done based on the plotting graphs. The results show the exposure parameters has significantly influenced the value of SNRN. Further experimental works are performed using triangulation technique on welded sample. The deviation between the calculated depth of defects and actual results is less than 1.0mm.