On Statistical process control study for front door outer panel of a passenger vehicle through process improvement

The clearance between the die and punch for the trimming operation set could lead to one major defect that is burr formation on the sheet metal component. Hence, controlling this parameter is a necessity for getting a product without defects. Different studies have reported the burr height phenomenon by varying the sheet material and die clearances. From the previous analysis die clearances below 15% suffers formation of burr therefore is a challenging task to control burr formation. In the present study, an effort has been made to reduce the burr formation factor to control/eliminate burr formation while dealing with sheet metal operation for the Front Door Outer (FDO) panel of the vehicle. Four different clearances between the punch and die, that is 12%, 11%, 10%, and 9% are considered for the study. The results of the study suggests that 12% clearance the burr height was within the range of 0.737–0.663 mm. Similarly for 11%, 10% and 9% die clearance, the burr heights are 0.734–0.618 mm, 0.729–0.655 mm and 0.717–0.655 mm respectively. The burr height of 9% clearance die is very close to the acceptable higher range of 0.715 mm, while it maintains to remain within the lower acceptable range of 0.65 mm. The study suggests that trimming with 9% clearance provides better accuracy with a minimum burr within the acceptable range of 0.65–0.715 mm. Further a statistical process control for the process has been done which supports the optimized results.