18 Oct Bottleneckin it Down
A relay race is won and lost by the slowest runner! Bottlenecks are like the slowest runner.
Why would I want to do a Value Stream Map, Capacity Analysis or Spaghetti diagram and what should I do with the information once my team has worked hard and developed it? Well, the answer to the question is certainly not display all the information to everyone around so that you can have a good dog and pony show about process improvement the next time a VP comes through (although if you follow through, it is the beginning of a great story). The real reason we go through all of that work is to identify key areas of improvement opportunity and start to implement changes that will allow better performance of the value stream.
One of the key areas of improvement that these tools drive us to is bottleneck elimination. A bottleneck is the process within the value stream that limits the output. For instance, if there are 6 steps in the process of creating a customer order (taking the call may be step 1, Engineering review of the quote request may be step 2 and so on), whichever step requires the longest amount of time to complete is the bottleneck. The output of the value stream can never be greater than output of the bottleneck process. As bottlenecks are identified and eliminated, products or information will flow through them more rapidly and new bottleneck processes will be identified and will need to be addressed.
In order to eliminate bottlenecks, you may consider the approaches below. Of course, the right one will depend on the specific set of circumstances in your value stream.
- Balance the workload: Other processes may have excess capacity that can be utilized to offload some work from the bottleneck process. This is typically a very good method to alleviate bottlenecks.
- Hold a kaizen event to reduce the non-value-add portion of the work.
- Hold a kaizen event to reduce non-value-added work from another process so that work can be offloaded from the bottleneck. This has the added benefit of not disrupting the bottlenecked operation until some work can offloaded. Another kaizen event should follow to reduce non-value-added work in the bottleneck process once some of the pressure has been relieved.
- Follow the high level value stream mapping with a detailed process map of the bottleneck and look for improvement opportunities.
- Add resources to the bottleneck. Notice that this is the last suggested approach and I hesitate to put it on the list because it is very overused as a means to reduce bottlenecks. We typically jump to this one first, when it should really be pursued last. It made the list because there are times when adding resources is the only way to reduce the bottleneck, but this should be used primarily when customer demand has increased to a point that the bottleneck cannot keep up, rather than as a solution for poor process efficiency. Bottom line: Make sure you have the data to support the solution of adding more resources before you consider it as a solution.
Good luck and keep looking for the bottlenecks!