The Project Goal: Reduce Transponder Defects by 90%
Follow the DMAIC Roadmap
Define
Establish… Collect the facts about the opportunity… Develop a clear definition of the practical problem and the defect to be fixed… Deliver A completed project contract and process map …
Six Sigma Project Example
Define the Problem
Goal/Objective: Improve the transponders First Pass Yield (FPY) from 19% to >90% by July 2016.
Problem Statement: Between January 2016 and April 2016 we inspected 394 transponders. We had an internal failure rate of 81%. Most transponders fail for signal integrity / output power. The signal power is too weak. Transponders are part of a remote control positioning system that relates a locomotive to a relative position on the track. This is a safety feature for speed regulation of remote controlled locomotives. Transponders that fail have weak output and the signal can be missed by a locomotive. Missing a signal causes the locomotive to stop, affecting yard production. Productivity at Laird is also heavily affected. The defect is found on the production line interrupting production. The failed transponder will be tested several times before being sequestered. The failed transponder must be replaced. It usually takes several iterations to find an acceptable transponder. This problem has a long history.
Project Scope: We will be investigating the transponder testing and assembly process from the delivery of raw material to QC through shipping.
Benefit: Reduced labor cost, reduced scrap / material cost, improved on time delivery, improved customer satisfaction and improved employee satisfaction.
Multi Level Pareto
The Multi Level Pareto is used to identify where we should focus our investigation. In this case 80% of our issues are caused by Communication Loss.
Measure
Verify… The Measurement System… Deliver a robust system to identify the “Good” From the “Bad”… Quantify the improvement opportunity and characterize the process with the revised process baseline…
Measurement System Analysis (MSA)
Using Minitab software we can confirm the reliability of our measurement system
Analyze
Screen… All families of variation and the potential “Troublemakers”… Develop the key to solving the problem… Deliver the identified list of a few troublemakers… the few “Key X’s”…
Analyze the Process Using a Process Map
Using process mapping we identified critical inputs that causes the defects
Improve
Isolate… and identify a way to rectify the “Key X”… Deliver a practical, proven & permanent way to fix the process…
The Improve Phase
The team made changes to the printed circuit board based on what was learned during the analyze phase
Control
Design… A robust control system… preferably a fool proof system… Deliver a system to sustain the improvements…
Control Phase
To make sure we maintain the gains we changed engineering drawings, changed the standard work and tracked the number of defect found daily