Takt Time and Leveling – What’s The Point?

A few days ago I wrote about asking “What is your takt time?” and the likely responses to that question. But in my list of common responses, I left one out – “What’s the point? We get everything out by the time the truck leaves.”

Here’s a real-life example: In a high-volume consumer goods factory we had a daily transportation cycle. Shipments left once a day. Parts and materials arrived once a day. Although the operation was not without its glitches, the process itself incorporated a lot of automation (another story entirely), and the time through the machinery was pretty quick.

We were trying to implement the production leveling (heijunka) into the enterprise flow between the factory and the distribution system. While the mechanics were very straight forward, leveling the model mix during the course of the day encountered a logical question: What’s the point?

And what is the point? With or without model-mix leveling the same stuff ended up on the truck at the end of the day, and the total amount of inventory in the factory was not going to dramatically change. So why go through the trouble, especially of working changeovers on the packaging equipment, when there was apparent no net effect?

The question is a logical one until we understand that takt time (or pitch in this case) is not a production quota. It is part of a standard.

What’s so important about standards?
Without a standard, you can’t detect a problem.

Daily management is about rapidly detecting, correcting and solving problems. This is much easier to do when dealing with small problems before they grow into big ones.

The “What’s the point?” question even gets asked in the course of many lean manufacturing implementations. The operation reaches a level of performance that is “good enough” – for example, everything makes it onto the truck by the end of the day – and they are satisfied with that level of performance. This is when continuous improvement stops.

Have all of the problems been solved? Has all of the waste been removed? Of course not. But the next level of problems, and therefore the next level of performance, is under the radar.

In the factory I described above they had more demand than they could handle. They were already working 24/7, and were working to add capacity. They wanted to speed up the automation, and possibly even add additional lines. Yet, during the course of a day:

• They lost many units to defects.
• The lost production to machine stoppages and slow-downs.
• They had part shortages and frequently substituted one product for another in the shipments, and made it up tomorrow.
• Because they were “behind” they relentlessly kept the lines running, only to find defective product in final inspection.

The list goes on. They are all familiar things.

So what is the point of applying leveling product mix and establishing the discipline of a takt time or pitch?

Honestly, there isn’t any point unless they also implement a leadership process to immediately call out and respond to any slippage or deviation from the intended pace and sequence of production.

So – what started out as a question about a common tool or technique in the TPS has come around to what the core issue really is when that “What’s the point?” question is asked: Lean manufacturing is not about the tools and techniques. It is a system to assist a proactive leadership culture that is almost obsessed with finding and fixing the problems that keep them from achieving perfect safety, perfect quality, perfect flow, with zero waste.

A “problem” is any deviation from the standard. (And if you don’t have a standard, that is a problem.)

Two key questions:

Are we meeting the standard? If the answer is “yes” then:

Are we looking at perfection?

One or the other of those questions is going to drive you to address the next level of problems.