STATISTICAL PROCESS CONTROL TECHNIQUES AND ITS APPLICATION TO WELDING PROCESS AT DOCKYARDS

Ahmet KAPICI

MBA Thesis, 2005

Adviser: Dr. Adalet ÖNER

Key Words: Statistical Process Control (SPC), Quality, Quality Kontrol, Welding Process

In this study we tried to implement SPC techniques to welding process of ship building and reparation projects at Dockyards. Because of welding process is very complicated, the process was investigated in detail, a flawchart for the welding process is formed, types of welding defects is determined and a fishbone was generated for each of them. Which datas to collect and evelauation methods of defects was agreed on. Reasonable groups and sub groups that is statistically independent is decided and as a result of these activities a new procedure for data gathering, data analyse and evaluation was developed. X-ray radiographic inspection datas were used to form SPC charts. Radiographic inspection form that is used at stanbul Tersanesi Komutanlıgı is revised and transferred into MS Excel sheet, and a basic software is developed. In this way a useful system is constituted to collect datas orderly, to classify them and to get ready to analyse. By improving this software it is provided to draw c-charts, histograms and pareto charts, and to observe the performance of welders.