Questions from the Field #2: Lean Engineering

Strategies to Maintain an Even Workflow with Variable Takt Time in Lean Thinking

There are three things to consider when answering this question:

1. When implementing Lean thinking, it’s common for Takt time to vary due to changes in demand. However, there are strategies that can be used to maintain an even pace and workflow. It’s important to note that running to a variable Takt time is not unique to engineering processes; any time demand fluctuates against a fixed available time, Takt time will vary (Takt = Net Available Time / Demand). To balance the workload and Takt time, various work balance scenarios can be developed depending on the Takt time (longer or shorter) and cycle time (longer or shorter), which is a fundamental aspect of creating flow in Lean. However, a detailed explanation of these strategies is beyond the scope of this discussion.
2.  You can set an artificial Takt time that is faster than actual demand. Get the work done quicker and move on to something else. If something takes less time or has a long Takt time, complete the work and move on. In order to keep this person productive, cross-training upstream and downstream is essential.
3. Follow the rule “when you can’t flow, pull“. One-piece flow, based on downstream pull and paced by Takt time, is the ideal approach for Toyota Production System (TPS). In the early stages, flowing to Takt will be difficult. For many engineering organizations new to Lean, simply achieving flow can be a significant accomplishment. Connect the processes so that the customer (downstream process) can pull the work when they have time available. This will begin to set the workflow in motion while you figure out the Takt time.

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