Takt Time: A Guide to the Very Basic Lean Calculation

​Acknowledgments

Icreated this book with the help of more than fifteen different business resources. These academic articles and books are all cited at the end of this book. A number of people have influenced my learning journey and my entire career. I would like to acknowledge them here.

Esraa Soliman: My lovely wife and partner. She encouraged me to write and publish this work. In fact, she always encourages me to do creative work.

Jeffrey Liker: Professor at the University of Michigan and author of The Toyota Way and the amazing Toyota series of books. His impressive work on Toyota inspired and influenced my learning about the Toyota Production System. I would really like to thank him for his indirect involvement in this work. Many examples included in this book were originally from his books. Although I have never met Jeff face to face, we have had great communications over social media platforms.

Chris Duklet: A lean manufacturing leader from the United States who works in the field of health care. He has contributed to this work by reviewing the book prior to publication and giving me useful recommendations and advice.

Attia Gomaa: Professor at the American University in Cairo who influenced my teaching career at the university and taught me how to become a good trainer.

Steven Borris: A business consultant, author, and friend from England who influenced my writing career. He encouraged me to write and publish. Steven was my mentor on lean manufacturing, helping me first to understand the basics, after which I developed my understanding through deep practice and self-directed learning.

Eslam Soliman: My friend and a professor at the Assiut University. His PhD is from the University of New Mexico. He has influenced my entire writing career by giving me recommendations and advice on how to write and publish. He revised my published works many times and kept inspiring me after every piece I wrote and published.

Takt Time

What is takt? Takt is a German word for pace or beat. Takt time is a reference number that is used to help match the rate of Production in a pacemaker process to the rate of Sales.

One of lean manufacturing’s most important calculations is takt time, or the rate of customer demand for a group or family of products produced by one process. Takt time is calculated by dividing the effective operating time of a process (be it a shift, a day, etc.) by the quantity of items that the customer requires from the process in that time period. For example, the operating time for a process is 28,800 seconds per shift. But the effective operating time is the operating time minus allowances, which can include planned downtime, lunches, breaks, team meetings, cleanup and planned maintenance. Assuming 1 hour for allowances, unplanned downtimes, changeovers (signify waiting waste) and other internal problems are those variables that need to be improved to have the best effective operating time. If the customer demands 420 pieces of a product during an eight-hour shift, the takt time will be 25,200 divided by 420, or 60 seconds. This means that based on the available time, on average, the customer is buying one unit every 60 seconds.

Obviously, the intended cycle time of an assembly process, called planned cycle time, is usually less than the takt time. So, in less than one hour, we expect this machine on this shift to produce 60 pieces of product. Any interference such as unplanned downtimes would reduce the operating