Even the hot projects approach has its place in this approach. For example,
it may be that Process 1 is a severe bottleneck and regularly shuts down other
operations, causing late shipments. By all means start with Process 1 and the
Intermediate Process Loop. There is no lean law that says you must start with
the Pacesetter Loop, but other things being equal, this loop is the logical starting
point. That is, start closest to the customer and create a leveled pull at the pace
maker, beginning to create a sense of takt time in the value stream at that point.
If we return to the Tenneco case three years later, you’ll see they initiated a
value stream approach at Smithville. They began with a model line and value
stream mapping. They found that the result of their initial foray into lean
through events still left them far from a lean model. The new wave of value
stream improvement got them additional results as dramatic as the initial wave
of radical kaizen events.
Case Example: Tenneco Smithville, Value Stream
Approach, Phase II
After the one year of radical kaikakutransformation through kaizen
events in 2000, the plant did not make a lot of improvement, and in
fact slid back from where it had been after the events. The 5S and other
lean systems were not always followed, and the plant started to become
less organized. This began to be seriously addressed in 2003-2004 when
the plant shifted to a value stream approach emphasizing overall material
and information flow across processes creating connected flows. The
new approach was the “value stream model line approach.” The Toyota
product family was selected as the pilot. Rick Harris’s firm was brought
in, and the model of a purchased parts supermarket and tugger route
described in Making Materials Flow^4 was adopted.
When Smithville mapped the current state, they found that despite the
earlier radical kaizen, they had islands of lean connected by push systems.
The current state value stream map is shown in Figure 19-7. Notice all of
the push arrows. Basically we have inventory coming in, being pushed
through various manufacturing processes, being pushed to one stage of
assembly (welding of subassemblies) and then pushed to final assembly,
where the muffler (brought in from outside), tail pipe, and such, are all
welded to a complete exhaust system. The total lead time from steel
coming in until exhaust systems were shipped out was 17 days.
The future state vision, which has been implemented, is shown in
Figure 19-8. We will not go through all the details of the map, but
here are some of the highlights:Chapter 19. Lean Implementation Strategies and Tactics 413(^4) Rick Harris, Chris Harris, and Earl Wilson. Making Materials Flow. Cambridge, Massachusetts:
Lean Enterprise Institute, 2003.