1. Client Background

Client was a tier-1 automotive supplier that supplied wire harnesses for OEMs. They were looking to reduce the cost of their product by getting the wire strand diameters as close to the minimum of the specification as they could safely do and maintain 5 to 6 sigma.

2. The Challenge

Each step of the cable-make process had an effect on the size of the strands. Making a change at the dies in the drawing process could not be done until all the subsequent processes were understood. There were multiple machine types at different speeds in both bunching and extrusion (coating).

3. The Approach

We had to start at the end and work our way forward!

• Investigate the effect of extrusion and bunching on the strand diameter.

• Investigate how the varying speeds and machine types affect the strand size.

4. The Solution

Once we learned all of those answers, we were able to use the data to optimize machine speeds to a point where ‘drawdown’ was controlled and sustainable. Then, we could step back to the wire drawing process and reduce the strand size to a point where it would almost never (6-sigma) go under spec.

5. The Results

This reduction in strand size was able to save $80,000 in copper cost per year.

Since we tweaked machine speeds accordingly, we also were able to develop a more predictable output around the plant.

This adjustment also reduced machine maintenance downtime.

6. Key Takeaways / Lessons Learned

At the end of the day, it's all about getting good data. A simple decision like “what size die should we buy” can have a massive impact on the cost of producing a product, and the best way to make that decision is to get good data!