Metal propellers for small drones are manufactured in two steps: milling and assembly. Each propeller is made up of three pieces: one central disk (part A) and two blades (part B).
The disk and blades are fabricated by a single milling machine that has a set up time of 90 minutes switching between parts A and B. Once the machine is set up, the activity time for parts A or B, regardless of type, is 30 seconds (30 seconds = 0.5 minute) each piece.
Currently, the milling machine rotates its production between one batch of 80 disks (Part A) and 160 blades (part B). Completed parts move only when the entire batch is produced.
Then, the propeller is assembled manually to form the finished propeller. The three parts components are required for each unit of final product. Each product requires 40 minutes of labor time to assemble. There are 12 operators for the propeller assembly.
Note: there is huge demand for these propellers and everything that is produced can be sold! ( capacity-constrained)
The capacity at milling is 80/(90+80*0.5 + 90+160*0.5)*60 min/hour = 16 propeller components (1 disk and 2 blades) per hour.
The capacity at assembly is (1/40)*12 workers*60 min/hour = 18 propellers per hour.
1. One way to increase process capacity is to
a. Increase the size of the batch at milling.
b. Decrease the size of the batch at milling.
c. Increase the size of the batch at assembly.
d. Decrease the size of the batch at assembly.
e. Add more operators at assembly.
f. Decrease the number of operators at assembly.
g. None of the given statements are correct.
2. Which batch size for the milling machine would minimize inventory without decreasing the current flow rate? Select the answer below that is closest to the correct answer.
a. 40
b. 80
c. 100
d. 160
e. 200