No doubt the company president had thought that the latest machines and equipment would readily solve his factory’s
various problems.
He may be proud to inform us, “This is great! This new equipment will double our production capacity!” or, “This
brand new equipment will take care of our quality problems.
He might even go so far as to claim, “This new equipment will enable us to meet our client’s delivery deadlines.”
Let us suppose that the factory has usually been incapable of meeting its client’s short delivery deadlines, and that is one
big reason why the president bought the latest equipment, which is supposed to cut processing time in half. The goal
here is to shorten the manufacturing lead-time.
Shortening lead-time by reducing processing time is a mighty bold and eccentric way of doing things. We can spend a fortune on faster processing machines and still not shorten the lead-time one bit. We might succeed, however, in shortening the life of the company.
When we look at production as a flow of materials, we can recognize four main categories of components in this
flow: retention, transfer, processing, and inspection. The first thing this teaches us is that making things requires much
more than just processing.
As we go through the manufacturing process, imagine that you are one of the parts that has been delivered to the
factory and is about to undergo the entire lead-time of the manufacturing process. To start with, you are warehoused
along with the other purchased parts and materials. This falls under the “retention” category. Now, it would be nice if the
processing machines could walk over to the parts warehouse,pick out the things they need, and process them, but we have not reached that day yet. So the factory needs to move you and all the other goods from the warehouse to the processing machines, a task that falls under the “transfer” category.
Next, you and the other materials that have just been delivered to the processing machines sit in a pile until the
machines finish processing the previous lot of materials. This sometimes takes a long time. At last, the machines start in
on the first of your lot of materials. You are the last in that lot and are still waiting. All of this waiting is part of the
“retention” category.
Finally, you—the last of the lot—are picked up and, in a few brief seconds, get processed. Those fleeting seconds are
in the “processing” category.
After being processed, you are plopped onto a pile of processed units. Then you go through another round of retention,
transfer to the next group of process machines, more retention, and processing.
To return to our music analogy, we can say that the four parts of this manufacturing process—retention, processing,