Using takt time as a tool means you design your value stream and processes from the perspective of delivering value to the customer.
Many ideas get thrown away because they “won’t work here.” While the details might not apply, it’s a serious mistake to throw out the heart of the idea along with the details. This happens often in lean applications. The focus becomes “does this idea fit?” Instead, the focus should be “what can we learn from this that will help us solve a problem?” As an example, let’s walk through an idea that many discard out of hand-takt time.
Takt time is derived from the German word taktzeit, which translates to clock cycle. In the context of lean-which focuses on the customer-it can be defined as the time needed to produce a product to meet customer demand. Using takt time as a tool means you design your value stream and processes to produce at a rate that meets customer demand.
This is great if you make something with steady demand, but not if demand varies as in, for example, a hospital emergency room. If you asked a hospital to design its emergency room to takt time, the administrator would throw you out. They don’t know whether they’ll get 50 people or 200, or whether they’ll get sprained ankles or heart attacks. Therefore, takt time doesn’t apply and-if they go one step too far-then lean doesn’t apply to them either.
Let’s look at the heart of takt time and the questions it forces us to ask. Is our process capable of responding to customer demand and-if not-what is the impact? What is the impact if we overproduce or underproduce? How hard is it for us to make adjustments? What is the impact to the customer of not being flexible? Addressing these questions makes you focus on understanding the current state of the process from the perspective of value to the customer.
As always, answers lead to more questions. How can we align our process to our customers’ demand rate? Where we can’t, what risks must we manage? How should we respond when the demand rate changes? Can we use market tools to shape customer demand for less waste? There are no unique answers, but addressing these questions sharpens your focus on managing to meet your customer demand rate.
Take K-Mart as an example. Although there is much that should not be copied from this deeply troubled organization, one change it made in response to a specific customer demand rate-long lines at the registers-is worth looking at. Realistically, K-Mart has no idea how many customers will really show up on any given day, or when they’ll reach the registers. So K-Mart instituted a response mechanism: when the lines grew past five customers, someone was pulled from the floor to open another register. K-Mart couldn’t control the rate of customer demand, but it could react when demand changed.
That is the heart of takt time.
Boeing had a similar experience the last time demand for airplanes spiked as airlines around the world scrambled to build their fleets. Boeing added capacity, pushed its workforce and manufacturing systems to the limit, and created problems that persisted for years.
At the next spike, Boeing decided that instead of doing whatever it took to keep up, it would manage customer demand within the limits of its system capability. This was a difficult decision because it required difficult discussions with customers. But it paid off as a sound decision for Boeing.
Are you raising the questions that takt time forces an organization to address? Are you leading the discussions? Are you helping your colleagues understand takt time and focus on what it means to your organization?
Jamie Flinchbaugh is a founder and partner of the Lean Learning Center in Novi, MI, and the co-author of The Hitchhiker’s Guide to Lean: Lessons from the Road.He shares his successful and varied experiences of lean transformation as a practitioner and leader through companies such as Chrysler and DTE Energy. He also has a wide range of practical experience in industrial operations, including production, maintenance, material control, product development and manufacturing engineering. Jamie is a graduate fellow of the Leaders for Manufacturing Program at the Massachusetts Institute of Technology, where his research thesis was on implementing lean manufacturing through factory design. He also holds a B.S. in Engineering from Lehigh University in Bethlehem, PA, and an M.S. in Engineering from the University of Michigan. To contact Jamie directly, go to the web site www.leanlearningcenter.com.