Two Six Sigma projects led by Continental Teves (CT) employees trained by NC State University Six Sigma experts resulted in savings of more than $800,000 annually.
Teresa Singleton, process quality technician, and Bruce Martin, manufacturing engineer, completed Six Sigma projects at the Green Belt and Black Belt levels, respectively, over the past two years to achieve these savings. Six Sigma is a quality improvement philosophy that uses statistical analysis and scientific problem solving methods to standardize processes and reduce rework or mistakes.
Green Belt projects strive for at least $25,000 in savings for the company. Singleton, a third-shift employee, led a project that had been reviewed by two earlier teams. This time, the project recovered $359,000 in annual savings. Leading a project at the Green Belt level is unusual; leading one and achieving this savings volume is remarkable.
Missing Shipments
“The project needed to be done to prevent missing customer shipments,” said Singleton. “It was important to me because I worked daily with the people who had to do all this rework. Those people, the supervisors and the workers, were frustrated because they were working overtime, through breaks and lunches just to meet the regular schedule.”
Continental Teves manufactures Ford brake and axle assemblies. In the assembly line area where Singleton worked, the lateral run out (LRO) of the axle assemblies was too high, resulting in an almost 25 percent failure/rework rate for each rotor assembly on the line. An axle that is too high results in the vehicle vibrating or wobbling when the brake is applied.
Goals Exceeded
The Green Belt project objective was to achieve a 50 percent reduction in this failure rate and a 5 percent reduction in direct labor costs by the end of 2005. The solution was to have a supplier change their machining rotor process. All project goals were exceeded.
Using Six Sigma tools such as cause and effect analysis, process capability analysis and others, Singleton and her team achieved annualized savings for 50 weeks equal to $359,944. Mentors for the team were NCSU-trained Steve Gormley, quality assurance supervisor and Black Belt, and Curtis Blaylock, production area manager.
Other improvements include two maintenance technicians now available to help in areas other than corners for changeovers and other tasks. The first shift corner supervisor now has time to manage two additional production assembly lines. The manufacturing engineer assigned to this issue is now focused on other projects. The project also produced a new gage that easily measures rotor LRO.
Singleton received her Green Belt Six Sigma in late 2004 via an onsite course by NC State. She commented that the training was thorough and she is applying the tools she learned to many other areas now.
Black Belt
Martin pursued Six Sigma at the Black Belt level. He wanted to lead a project that would generate at least $100,000 in annual savings.
Martin worked with Gormley, another Black Belt candidate, on a project that revolved around a component that averaged 100,000 units per week with an average value of $13 per unit. The scrap rate was 2 percent. Martin, Gormley and his team needed to reduce that scrap rate by 50 percent in six months. Their annual scrap rate cost was $400,000.
The team chose this project due to its huge potential savings. The team also had seven years of variable data for analysis with Six Sigma tools to determine the root cause.
Big Savings
The results of this Six Sigma project included a scrap reduction from 2 percent to .02 percent. Annual cost savings were $122,000 per machine. Because they used four machines, total annual savings were $488,000. Using the Six Sigma process, their process capability improved from 15,000 to 400,000 units. They also discovered a new type of cutting tool that saved $21,000 per year.
A wonderful additional benefit: these results were shared with other plants and the same process is now being used worldwide. All these locations are saving time and money.
Martin received his Black Belt Six Sigma training at NC State in Raleigh; he was certified in August 2005. “I thought the training was excellent, and I had a great time doing it,” he said. “The class structure was solid, and the instructors were thorough and clear.”
June 2006
