Takt Time
Takt Time is the beat of your process. When your process is perfectly balanced the complete workload and capacity throughout the complete value adding chain is best utilized to fulfill your customer demands.
So this is already it, the customer determines your Takt. Just have a look on your available net production time and divide it by the rate of the customers demand. I do the exact same thing, when I’m in the role of a project manager I want to optimize the available resources and straighten out the workflow over the expected time needed to finish the project. In the Lean World it is also important to understand the difference between Cycle, Lead and Takt Time if you are running a sophisticated Project or SIX Sigma initiative.
So let’s have a look at the differences
Lead Time VS Cycle Time
It happens very often that people mix up Cycle Time with Lead Time. Most common is the thinking that Cycle Time is the time needed between order placement and delivery while others think it is the pure time between two deliveries.
To put this straight, Cycle Time is the time from when the work is started until it is ended. This brings us to Lead Time.
Concerning Lead Time, it starts with the first contact from customer side e.g. the placement of an order and ends with the shipping.
Easy example:
Order placed by customer on July 12.
Order processed (actually fulfillment of order July 18-20.
Order shipped on July 20.
This gives you a Cycle Time of 3 days but a Lead Time of 8.
This exactly the point where value stream mapping comes into place and can help you on cutting down Lead and Cycle Time, but I will get you there in a different article.
Don’t get on the wrong path of thinking that Cycle Time is the pure value adding, it is simply the time you need for processing the order. That is the reason why should focus on Cycle Time when starting lean initiatives and make your way from there.
Takt Time
Yes it comes from Germany, TAKT comes from Taktzeit, meaning the rhythm of music. TAKT is therefore the beat of your process it is the measurement of your existing production. The Takt Time gives you the maximum amount of time to meet customer demands. In other words Takt Time is the heart beat of your customer and if you are not able to supply your customer in Takt you will bring your customer in struggle. Then you are very quickly no longer a supplier
So what is the Takt Time formula:
(Net Operation Time Available for Production)/(Customer’s Demand)
Always in the given unit of time.
Let’s make an example with the automotive industry:
Your OEM wants 1.000 cupholders per day. You have 8 hrs shift working two shifts per day. That gives you 16hrs per day. Then you deduct times for breaks, distribution time and for preventive maintenance measures, we assume 75mins per shift, this gives you:
16 * 60 = 960 minutes
960 - 150 (75*2 Shifts) = 810 minutes
810 minutes / 1.000 cupholders
= 0,81 minutes per cupholder
or in other words you have 48,6 seconds for one cupholder
Having a look on this calculation you still have to consider some factors, such as operations that are done simultaneously.
The tricky part with Takt Time is that it is based on the assumption that you have a continuous amount of demands coming in from day to day. With high fluctuations on demand you will have to readjust your Takt Time from time to time.
Takt Time is also used to calculated a couple of other parameters, such as batch size, work in progress, shifts needed or operators needed.
What to say in the end…
If you are trying to run KAIZEN actions or CIP measures the first thing to understand is what does Cycle, Lead and Takt Time stand for. Only with the right setting in the beginning your improvement efforts will show an effect.
