The analyses results showed that there weren’t any significant
differences on the critical dimensions, but the most important fact
was that the radial accuracy in the defined diameters was
unsatisfied. Experiment was repeated with external clamping
system, but this time with burr classification, and controlling
surface for clamping on parts. Results were analyzed and final
decision made about external clamping system application in the
machining area.
After repeated experiment with external clamping system
better results were obtained while, in the same time, all critical
and functional dimensions had good capability. The most
important conclusion was that dimension of burr hadn’t any
important impact on machining area.
Final decision was that the external clamping system will be
applied on one production line and, if proved acceptable, after
certain period of time will be applied on others production lines
and map this solution on the similar castings.
To make that possible some simple modifications was needed
on the casting die to secure quality surface on the castings for
external clamping.
In this, final phase of DMAIC methodology, a control plan
was developed to ensure that processes and products
consistently meets our and customer requirements, and to check
how external clamping system impact on quality production
level [13, 14, 15].