Optimization of Electrode cap Life and Tip Dressing Time of Resistance Projection Welding Machine for Automotive Applications

Abstract

Automobile Industry is one of the largest industrial sectors in the world. The automotive industry involves innovation, creation, science, technology, ideas that drive the economy, people and the whole nation. Now a days, to compete with the competitors it is necessary to produce finish goods at lower costs without compromising quality of the product. In an automobile industry different types of sheet metal process are involved to produce the components like blanking, stamping, welding, cutting, machining etc which use sheet metal as a raw material for producing the finish goods. In automotive industry variety of fasteners are used to produce final assembly. For using different types of fasteners in the sheet metal, different types of welding methods are used depending upon the type of application of the final product. Present study is dealing with the resistance welding process. All the resistance welding such as spot welding, seam welding, projection welding etc. are worked on same principle of heat generation by using the property of electrical resistance of the metal. When a current pass through electric resistance, it produces huge amount of heat at the contact point of the interface. This cause the melting of the small amount material at the interface and joined after solidified. The aim of this study is to optimize the electrode cap life used in projection welding machine. Pareto charts, root cause analysis, OEE methodology is used to identify the problems and improve the process to remove common causes of variation. The design of experiments (DOE) method is used for collection of data. Moreover, rejection due to wrong nut welding, reverse nut loading has been eliminated with the help of Poka-yoke design concepts. There are different studies is carried out and three different options are suggested and dummy electrode has been introduced for optimization of electrode cap life and reduce the time required for the dressing of the electrode cap of projection welding machine.