The Effect of Cellular Manufacturing on Lead Time Reduction
Figure 5.8.2.1 shows a possible routing sheet for production of shafts. The batch size is 10 .
$$
\begin{array}{|l|c|c|}
\hline \text { Operation } & \text { Setup time } & \begin{array}{c}
\text { Run time per } \\
\text { unit }
\end{array} \\
\hline \text { Millcut } & 0.02 & 0.02 \\
\hline \text { Lathe } & 0.6 & 0.06 \\
\hline \text { Millcut nut } & 1.6 & 0.6 \\
\hline \text { Pregrinding } & 1.2 & 0.12 \\
\hline \text { Final grinding } & 1.2 & 0.16 \\
\hline
\end{array}
$$
a. Calculate the lead time in traditional job shop production. Hint: For job shop production, lead time has to be calculated assuming a sequence of operations. Therefore, you can use the formula in Figure 5.2 .2 .3 .
b. Calculate the maximum lead time for the case of cellular manufacturing, that is, using the formula in Figure 5.2.2.4. (Hint: First determine the cell driver).
c. For the given routing sheet shown in Figure 5.8.2.1, and for cellular production, find a temporal order of operations that yields minimum lead time.
d. For the given routing sheet shown in Figure 5.8.2.1, and for cellular production, find a temporal order of operations that yields minimal load (or minimum allocated time for the operation, that is, operation time plus wait time between the units of the batch) at the workstations.