The Significance of the Radiography Technique in the Non-Destructive Evaluation of the Integrity and Reliability of Cast Interconnects

Abstract

Significant changes in oil and gas drilling have emphasized the need to verify the integrity and reliability of drill stem components. Defects are inevitable in cast components, regardless of application; but if these defects go undetected, any severe defect could cause down-hole failure. One such defect is shrinkage porosity. Castings with lower level shrinkage porosity (CB levels 1 and 2) have scattered pores and do not occupy large volumes; so pressure testing and helium leak testing (HLT) are sufficient for qualifying the castings. However, castings with shrinkage porosity of CB level 3 and higher, behave erratically under pressure testing and HLT making these techniques insufficient for evaluating the castings’ integrity. This paper presents a case study to highlight how the radiography technique is much more effective than pressure testing and HLT. Keywords—Casting Defects, Interconnects, Leak Check, Pressure Test, Radiography.