Flaw Reduction in Low Alloy Steel Butter Welds for Productivity Improvement Using Six Sigma

Abstract

In this paper, a study on ultrasonic testing on fusion welded joint of ferrite steels for Oil and Gas refinery application. The weld defects are major concern leading to rework, higher costs and thus affecting the delivery schedule of the job. The process starts with long and circular seams in the job and subsequently carrying out the NDT to find any defects in weld area. A number of defects are being observed in the welding process. Defects in welding may be found out in different methods at surface and subsurface levels, i.e. by Ultrasonic Testing, Penetrant Testing and Magnetic Particle testing. This deals with an application of Six Sigma Define-Measure-Analyze-Improve-Control methodology is an integral part of a Six Sigma initiative, improves the process performance leading to better utilization of resources, decreases variations and maintains consistent quality of the process output.