Question: Williams Optical Inc. is considering a new lean product cell. The present manufacturing approach produces a product in four separate steps. The production batch sizes are 45 units. The process time for each step is as follows:
| Process Step 1Williams Optical Inc |
5 minutes |
| Process Step 2 |
8 minutes |
| Process Step 3 |
4 minutes |
| Process Step 4 |
3 minutes |
The time required to move each batch between steps is 5 minutes. In addition, the time to move raw materials to Process Step 1 is also 5 minutes, and the time to move completed units from Process Step 4 to finished goods inventory is 5 minutes.
The new lean layout will allow the company to reduce the batch sizes from 45 units to 3 units. The time required to move each batch between steps and the inventory locations will be reduced to 2 minutes. The processing time in each step will stay the same.
Determine the value-added, non-value-added, total lead times, and the value-added ratio under the present and proposed production approaches. If required, round percentages to one decimal place.
|
Present Approach |
Proposed Approach |
| Value-added time |
|
min |
|
min |
| Non-value-added time |
|
min |
|
min |
| Total lead time |
|
min |
|
min |
| Value-added ratio (as a percent) |
|
% |
|
% |