Page 232 - Orlicky's Material Requirements Planning

CHAPTER 11 Product Definition 211

FIGURE 11-7
12-4010
Level 1 items
assigned to
groups by
options.
A13 C41 L40 B88 F28 E10 D14

E10

A13 B88

F28 C41 L40

Common Stick Shift Mechanical
Steering

Items Used Only with Specific Option Combinations
Note that the last level 1 component item, D14, does not fit into any of the groupings.
When all four of the BOMs are broken down this way and their level 1 components are
grouped by use, items D14, H23, J39, and N44 remain unassigned because each of them
is used only with one or the other of the option combinations. Here the process must be
carried one step further. These items are broken down themselves, as illustrated in Figure
11-8, and their (level 2) components are assigned to the groupings by use.
The final result is shown in Figure 11-9, where all the items involved in our exam-
ple are grouped into the respective modules. In this example, the entire problem has been
solved by applying the technique of breakdown and group assignment.
However, if items D14, H23, and so on had not been subassemblies but single parts,
it would have been impossible to break them down. In cases such as this, the part that is
used only with a certain combination of options should, if possible, be redesigned. This
will not always be feasible, however, as illustrated by the engine in the original tractor
example. Special engine-block castings are used for diesel, and the horsepower option
entails different cylinder bores; the fuel and horsepower combinations cannot be disen-

FIGURE 11-8
Level 1 D14 H23 J39 N44
A breakdown of
unassigned level
1 items.
P24 P24 S36 S36
Level 2
R38 T65 R38 T65