Due to downtimes at the assembly operation it comes to the lowering of the overall equipment effectiveness by the complete automated robotic cell which is the part of the discussed assembling machine.The operation consists of more complex stations with many worn out parts, among them is also the robot manipulation with pieces where it comes to mechanical damage on the machined places. As we wanted to discover the reason for the downtimes by the existing process, we chose DMAIC which is a part of six sigma methodology. We established that the main reasons for the downtimes are nonstandardized interventions in the machine by its breakdown what results in the unexpected damage of the rivet gun and the robot collisions where it comes to mechanical damage followed by scrap-pieces that lower the quality. The most exacting and burdened part of the assembling machine is the rivet gun which is responsible for the 90 % of the machine downtimes. During the diploma work we made two main improvements: instructions for the assembly, dismantling, precautious check-up, rivet gun cleaning and the exchanged robot gripper that causes no mechanical damage of the products.
|