TOCICO

30 Years of Success: TOC & Throughput Improvement at GM (General Motors), one of the world’s largest auto makers, is also one of the world’s most productive manufacturing organizations, on par with the best of its global competitors. Part of this reason is its ability to design and efficiently run high volume assembly plants. This is a result of many coordinated efforts, but one of the biggest reasons is the implementation of processes based on the concepts found in the Theory of Constraints. These first appear in 1987 at the new Detroit Hamtramck assembly plant, which was struggling to make its demand numbers. Working with GM Research, plant controls engineers developed the Throughput Improvement Process (TIP) using the analytical tool developed by Research called C-Thru. C-Thru included the basic factors found in The Goal – define a system and its dependencies, capture variation, and perform an analysis to find the bottleneck. By focusing resources and improvements on the bottleneck, throughput improved with each iteration of the TIP process. It wasn’t long before the Hamtramck plant went from the worst plant in the corporation to the best. These kinds of results caused the General Manager to spread the TIP process to other plants in his division, moving the lead TIP engineer from the plant to the divisional level in the process. Eventually, TIP was centralized at the GM Tech Center in Warren, Michigan. It became clear that part of the productivity problem was the way plants were being designed. The TIP process was adapted for future designs, predicting where bottlenecks would appear using simulation with current performance data and addressing them before the design made it into production. These design changes included the use of throughput accounting to justify ROI decisions, strategic location and sizing of buffers, designing in the bottleneck, design game training, etc. Now, every GM plant has a Throughput Improvement Engineer, every machine collects data from the day its turned on, and every design change to the plant must go through the simulation process based on TOC. A key aspect of TIP was its ability to continue to run despite management and organizational churn. GM has seen a torrent of changes in 30 years, but TIP, data collection, and the simulation process continue to run. As GM moves towards an Industry 4.0 transformation, the future includes more advanced throughput analytics that will build on and enhance the TIP track record of success. New capabilities will blend real-time or “live” date along with historical trending data. This live information stream will include performance and diagnostic data, giving GM the ability to identify bottlenecks, predict performance and self-optimize in real time.