4.Drum Buffer Rope Scheduling – One of the lessons learned from those who have read The Goal is that TOC’s scheduling system known as Drum Buffer Rope (DBR) is very effective for synchronizing the flow of work. It got its name from a troop of boy scouts hiking across country, but were continually slowed by an over-weight Boy Scout named Herbie. DBR was used to describe how a typical system has dependencies and statistical fluctuations that must be accounted for is work is to flow smoothly. In The Goal, Herbie was the Drum (constraint) because he walked at the slowest pace. The Buffer and Rope were techniques used to synchronize the Boy Scout’s walking pace as they traversed the path on their hike. Let’s look at each of these three components in a bit more detail.
In DBR there are three types of protective buffers to protect various parts of the process. As we just mentioned, there is a buffer in front of the CCR, but we also have a feeding buffer in front of any assembly process that combines with the CCR's product. Finally, we insert a shipping buffer to protect customer deliveries.
At the beginning of this series of posting I said I wanted to present my thoughts on Constraints Management (CM) and what it means to me. The fact is, Constraints Management is not simply a collection of tools used to solve problems….it’s much more than that. CM is even more than, as the name Theory of Constraints might suggest, just a theoretical basis for how a business enterprise should be run. Constraints Management, for me has become a way of life. It defines how I think and act both as a consultant and as a human being.
As I began looking through the Constraints Management lens years ago, I began to see the world differently than I ever had before. I realized that I had been looking at improvement in the wrong vein. By that I mean that I had fallen into the "fix everything" trap rather than focusing on the system's leverage point, the system constraint. So for me, what Constraints Management is, is the same name as my blog....it's all about focus and leverage. By being able to identify the leverage point of the system I'm working in, I can focus my improvement work on it to gain maximum effectiveness.