When you pick up your new vehicle at the dealership, you expect it to be free of exterior finish defects. Misty Bower examines how automotive makers at Ford set out to achieve that 'factory fresh look' no matter where in the world they are located.

The challenge of delivering defect-free vehicles after they have been transported thousands of miles by truck, rail, and ocean carriers to dealerships around the world, is a huge undertaking.
When Ford saw that vehicles that were exported overseas arrived at their final destination point with exterior surface defects, they knew they had to take action. The cost of repairs and the impact on customer satisfaction levels drove the company to search for a solution to the problem.
At the manufacturing plants, vehicles destined for export had transit protection film applied to horizontal surfaces. Transit protection film is a plastic sheet with adhesive on one side and a chemical-resistant material on the other side, designed to protect the vehicle's exterior during transit from the plant to the US port and then throughout the ocean voyage to the distributor.
During transport, large portions of the transit film lifted away from the vehicle surface and damage occurred. Dirt and debris became trapped between the loose film and the vehicle's finish, and the film lashed against the fresh paint and caused defects.
When the vehicles got to the port, the port processors had only a few options before loading the vehicles on the ocean-bound transport vessels:
* Wash the car (which often removed even more of the film).
* Take no action and chance that more damage would occur to the vehicle before arrival at the final destination.
* Repair the film - the cost of fixing the material was often more costly than the original application.
In June 2001, a customer-driven Six Sigma project team was selected and their mission was to reduce transit film-induced exterior finish defects on export vehicles. The team chose a Ford manufacturing facility in St. Thomas, Canada, their port processing facility in Delaware, and one destination market: the Middle East region.
Farzin Ghodsi, Black Belt at Ford Worldwide Direct Market Operations' Consumer Driven 6-Sigma initiative, explained the decision, saying: "We selected this market for our project because we knew that the extreme temperatures and difficult ocean transport conditions that our vehicles were exposed to during the journey would be a test for our processes. We knew that if we could reduce the defects under these extreme conditions, our improvements would be robust enough to create positive results in less challenging environments."
The team developed a high-level process map of the vehicle transit process and followed Grand Marquis and Crown Victoria models from St. Thomas to the port in Delaware.
Using data regarding film-induced defects from 2000-2001, the team produced a cause-and-effect diagram (fishbone analysis) to capture, categorise, and prioritise potential root causes of transit film induced defects.
The team examined the processes within production areas for potential cause of failure. At the plant level, they looked at many factors including transit film installation instructions, differences between operators and shifts, proper training of operators, type of transit film material used, and surface cleaning methods.
At the plant level, several key variables were identified that influenced the defect rate including:
m Transit film material - they identified that flexibility, adhesion and re-adhesion properties were important.
* Operator training and supervision.
Using Design of Experiments (DOE) capabilities in Minitab Statistical Software, the Ford team was able to screen the factors to determine which were critical for explaining process variation. The team was able to use Minitab to understand how the factors interacted and to identify areas for intervention and process improvement opportunities.
In order to validate their findings a 3-level experiment was designed:
* Use existing material but provide operators with good training and supervision.
* Use NEW material and good training and supervisors.
m Use no transit film.
The team used Minitab to compare the performance of a new type of transit film to an existing material. The data showed that the new material reduced transit film-induced defects from 289 per cent (2.89 defects per vehicle) to 129 per cent. Use of the new material resulted in a significant cost savings since the new material was less expensive.
In order to show that the level of operator training and supervision was a significant factor in defect rates, the project team compared two groups of plant operators. One group was provided with improved training, better film installation instructions, and increased supervision, and a second group of operators was not. When the Consumer Driven Six Sigma Team analysed the exterior surface defect rates upon arrival at the final destination point, the data showed that vehicles with transit protection installed by the group with no training had a defect rate of 129.4 per cent or 1.29 defects per vehicle as compared to the group that had received training at 104 per cent.
Using the software, the team identified the optimum conditions and quickly determined which factors were most important and most likely to yield improvements in the process being studied. Key variables were proven to have significant impact in this designed experiment.

Results

When the project started in June 2001, the original transit film-induced defect rate was 289 per cent or almost three defects per vehicle. Using the new material reduced defects to 129 per cent Using the new material PLUS adding increasing supervision and improved training reduced defects to 103 per cent.
The team was able to produce even more dramatic results when they looked at the data for the vehicles that were transported to the ports without the transit film. They found that the etch-resistant coating that was applied to Ford vehicles offered sufficient protection against damage for domestic transport. No transit film was needed until the vehicle was prepared for ocean transport.
They presented their findings to management and suggested applying the film at the port processing point versus at the manufacturing facilities. The plant management supported this recommendation because it could free up over 4500 square feet of manufacturing space that had been dedicated to transit film installation for other operations.
The decision was made to move the transit film application process from the manufacturing plant in Canada to the port processing point in Delaware. The minimum target savings goal for Six Sigma projects at Ford is $250000. This project resulted in cost savings in excess of $500000.
Since the results at the Delaware port were so encouraging, the same process changes have been proposed for expansion to 11 other facilities in the US by Spring 2002 and transit film installation operations are being relocated from manufacturing facilities to port processing centres. The team was able to develop ISO qualified process templates and put new process controls in place to control for export operations as well.

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Misty Bower is with Minitab Inc, State College, PA. USA. www.minitab.com