Theory of Constraints Handbook - James Cox Iii [504]
You should be able to fill in the blanks to the following statements:
B won’t happen without D.
In order to have B, we must D.
FIGURE 25-12 Cloud example 1.
C should answer the following questions:
For what is D′ needed?
What need will not be met if D′ doesn’t materialize?
You should be able to fill in the blanks to the following statements:
C won’t happen without D′.
In order to have C, we must D′.
The following check will also help:
If D exists, then C cannot.
If D′ exists, then B cannot.
The POOGI team’s analysis led them to understand the internal policy that forced orders to wait for quench tanks. It was not the lack of usable quench tanks in the company; rather it was the unavailability of the specific quench tank defined in the order’s routing. The company had previously set a policy that allowed production managers to move orders to capable work centers other than those specifically identified in the routing when the priority system indicated that the order was becoming at risk of being late (yellow or red) or already late (black). In order to avoid “unnecessary expenditures” of time (making changes to paperwork) and money (transportation costs to move the product from one plant to another), the company did not allow such “exceptions” for “green” orders. Our steel products company’s Cloud now looked like the illustration in Figs. 25-13 and 25-14.
FIGURE 25-13 Cloud example 2.
FIGURE 25-14 Cloud example 3.
Identify A, the mutual objective of B and C. Similar questions will enable you to verbalize the objective.
You should be able to fill in the blanks to the following statements:
[A] won’t happen without [B] and [C].
In order to have [A], we must [B] and [C].
Our steel products company POOGI team completed their Cloud.
3. Surface the assumptions of each of the necessary condition relationships and identify those that are invalid in the situation of conflict being analyzed.
The Cloud (as well as the PRT) utilizes the logic of necessary condition. Figure 25-15 illustrates the relationship between this logic and the logic of cause and effect that we have been using thus far.
FIGURE 25-15 The relationship between necessary condition and cause-and-effect.
By understanding this relationship, you can surface—and check the validity of—the assumptions that are being made by using some simple questions and fill-in-the-blank statements:
In order for A, we must11 B, because __________.
Why can’t A happen without B?
In order for A, we must C, because __________.
Why can’t A happen without C?
In order for B, we must D, because __________.
Why can’t B happen without D?
In order for C, we must D’, because __________.
Why can’t C happen without D’?
D and D’ cannot coexist because___________.
Why can’t B happen if D’ exists?
Why can’t C happen if D exists?
Note that you are looking for the “beliefs” that exist in the given situation. In Table 25-2 some of the assumptions surfaced by the steel products company POOGI team are given.
4. Using the erroneous assumption as your guide, define an injection that would enable the conflict to be eliminated. A good injection will enable you to “evaporate” at least one of the arrows in the Cloud. You should be able to fill in the blanks to at least one of the following sentences:
If [injection], then [A] can be achieved without [B] because _____.
If [injection], then [A] can be achieved without [C] because _____.
If [injection], then [B] can be achieved without [D] because _____.
If [injection], then [C] can be achieved without [D’] because _____.
If [injection], then [D] and [D’] coexist because _____.
The analysis of the steel products POOGI team uncovered the following facts, which were in direct contradiction with existing policies:
Allowing green orders to sit was not helping the company maximize flow, and in many cases led to expensive expediting later in the process.
Moving an order to an equivalent