Tower Automotive has practiced Lean manufacturing and had a continuous improvement department in one form or another since the late 1990s. Through these continuous improvement efforts, Tower was able to eliminate waste and reduce overall operational costs, helping the company survive when many other automotive suppliers fell by the wayside. Even with all of the improvements, however, Tower needed something else to help sustain projects, reduce variation within their systems and improve quality.

About Tower International

Tower International is a leading integrated global manufacturer of engineered structural metal components and assemblies.

The company supplies the automotive industry with body-structure stampings, frames and other chassis structures, as well as complex welded assemblies for small and large cars, crossovers, pickups, and SUVs.

Limited Initial Success of Lean Six Sigma Program

Thus, in 2007, Tower launched a Lean Six Sigma (LSS) program with the training of its first wave of LSS Black Belts. This was followed by two more waves of LSS Black Belt training in 2008 and 2009. While there was success with the first three waves of trained Black Belts, it was limited. Of the 40+ Black Belts certified, only 24 were even somewhat actively completing projects. When studied, it was determined that this was not necessarily due to a lack of desire by the Black Belts, but often due to a lack of Six Sigma understanding, and thus support, by their Champions. A majority of the Champions had not been trained in even the basics of Six Sigma, but were only directed to help support it.

In order to improve the support of Black Belts and the quality and completion of projects, Tower’s North American LSS department proposed a Yellow Belt Champion training session with North American leadership, including the president of the Americas, a number of vice presidents and plant managers. This proposal was met with great enthusiasm by the North American leadership, and thus, the training was put together.

Training the Champions

The main purpose of the training was to give the Champions at Tower enough basic knowledge in Six Sigma for them to help with project selection, resources and general support – all in an eight-hour timeframe. The challenge was to connect with leaders who had varying levels of knowledge; Tower had a couple of Champions who were Black Belts and others who had no training. To accomplish this, Tower took the path of having participative training, where the individuals with more experience in Lean Six Sigma would help those who had little-to-no training. The company also had a couple of operations directors give a small module on variation and project support to offer a different voice to the training.

Training began with a discussion of similarities and differences between Lean and Six Sigma, and how both can be utilized to optimize processes. As part of this training module, participants discussed the concept of Y = f(x) and how it would tie in to the remainder of the training. The training also included a review of the concept of statistical variation, and had a group demonstration of how problems can arise if the business chases normal process variation instead of designing processes to properly deal with it. Figure 1 illustrates sample data gathered in the demonstration (see sidebar for the instructions for the exercise). Notice the difference between the red and blue marks.

Instructions for Training Exercise Shown in Figure 1

  1. Using the red marker, align the marker above the yellow target and drop the marker straight down. Repeat 10 times.
  2. Using the blue marker, align the marker above the yellow target and drop the marker straight down 1 time.
    • With the ruler, measure the distance the blue marker hit from the target.
    • Move the exact opposite direction of the target from your previous hit the distance that you measured, and drop the blue marker at this spot. Repeat 9 times.
Figure 1: Training Exercise to Illustrate Concept of Statistical Variation
Figure 1: Training Exercise to Illustrate Concept of Statistical Variation











Project Support and Project Chartering

Next, it was on to the topics of project support and project chartering.

It was important for the Champions to understand all of the critical players involved in a Six Sigma Black Belt Project and how they could be tied into the project charter. The project support module discussed the roles and the importance of a project team including Champions, process owners, financial analysts, the Black Belt, the Master Black Belt, subject matter experts, data collection experts and ancillary department leaders. On a successful team, all of these functions participate actively.

The project chartering training module taught the group how to write a project charter. Although it is not the Champion’s job to write the charter, they must work on it with the team members and process owner to ensure that the LSS project aligns with their business objectives and vision. Additional focus was placed upon the problem statement, defect definition and project scope.

Project scoping has been an issue in the past at Tower. Many projects aim to “fix the world” – that is, they are too broad in scope – making it difficult for the team to focus on a specific defect or objective. Emphasis was placed on project scoping so Champions could better understand it and better help their teams with this function. To further enhance the knowledge from this module, the group broke into five different teams to write charters on potential LSS Black Belt projects for Tower in North America. They then reported their results back to the class, where the project charters could be further developed.

DMAIC Process and Key Stakeholder Analysis

After project chartering, the next modules focused on an overview of the DMAIC (Define, Measure, Analyze, Improve, Control) process and the key stakeholders analysis.

The objective of the DMAIC process overview was to inform trainees of the purpose of each step of DMAIC, some of the tools that Black Belts utilize in each step and how those tools tie in to Y = f(x). In this module, one of the more interesting discussions revolved around correlation and causation. The Champions agreed that the business often believes it has found a correlation between a cause and a problem, but does not either properly collect or properly utilize available data to determine if there is truly causation. As a result, they chase problems.

Another important thing for Champions to understand is the key stakeholders analysis. This is important for them to be involved in because many times Champions are needed to help break down barriers among stakeholders. These barriers can include resources needed, people in areas affected by a change, or even a parts supplier. With an understanding of these potential obstacles, Champions can help eliminate or minimize barriers more easily. At the conclusion of this module, participants once again broke into different teams. Each team completed a key stakeholder analysis on subjects such as the implementation of a facility-wide safety program and a Lean vision for the plant. The trainees had a high level of participation in these exercises and are able to use the knowledge gained from the exercises in future projects.

Six Sigma Projects and the Eight Wastes of Lean

The day was concluded with a discussion on what is (and what is not) a Six Sigma project, and a discussion of the eight wastes of Lean.

It was important for the Champions to understand that a Six Sigma project was one in which the business has a problem that it does not yet have the answer for and will utilize properly collected data, statistics, controls, some soft skills and a team to determine a sustainable solution.

In wrapping up with a module on the eight wastes, the idea was to have everyone leave with some ideas of what to look for when they returned to their departments or facilities. As part of the training, participants brainstormed wasteful issues and also broke into teams to study a Tower process flow, looking for where there was value and where there was waste.

Figure 2: Roadmap for Yellow Belt Champion Training at Tower Automotive
Figure 2: Roadmap for Yellow Belt Champion Training at Tower Automotive

Responses and Results

Some of the main participant comments from the training were:

  • “I never realized how important an MSA [measurement system analysis] was. I am going to make sure my folks never skip this step!”
  • “I am definitely going to be more involved up front on our projects from now on.”
  • “I now understand that all processes, manufacturing and transactional, can be addressed using Six Sigma.”
  • “Proper support, from the Champion to the ancillary functions, is critical for the Black Belt’s success with a project.”

While the final results will be shown over time, Tower Automotive in North America is going in the right direction with Six Sigma. In 2010, there were only 14 LSS Black Belt projects completed among 11 plants and the corporate office. In 2011, 24 LSS Black Belt projects were completed. As of March 2012, 23 projects are in progress. Completed 2011 projects represented a 75 percent increase in savings per Six Sigma project above 2010 figures. During the training session, an additional 28 projects were brought to the table from the plants to begin creating a pipeline of useful Lean Six Sigma Black Belt projects. All of this will contribute to a long, successful future for Tower Automotive in North America.

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