Macon Controls produces three different types of control units
used to protect industrial equipment from overheating. Each of
these units must be processed by a machine that Macon considers to
be their process bottleneck. The plant operates on two 8-hour
shifts, 5 days per week, 52 weeks per year. The table below
provides the time standards at the bottleneck, lot sizes, and
demand forecasts for the three units. Because of demand
uncertainties, the operations manager obtained three demand
forecasts (pessimistic, expected, and optimistic). The manager
believes that a 30 percent capacity cushion is best.
a. How many machines are required to meet minimum (Pessimistic) demand, expected demand, and maximum (Optimistic) demand? (Enter your responses rounded up to the next whole number.)
Demand Forecast Capacity Requirement (M)
Pessimistic _________ machines
Expected _________ machines
Optimisti _________ machines
Available capacity (hrs.) = 2 * 8 * 5 * 52 = 4,160 hrs.
Utilization = 1 - capacity cushion = 1 - 0.30 = 0.70
So, utilizable capacity = 4160*0.70 = 2,912 hrs.
Component | Processing time | Setup time | Lot size | Demand (P) | Demand (E) | Demand (O) |
A | 0.04 | 1.0 | 40 | 14,000 | 17,000 | 27,000 |
B | 0.20 | 4.5 | 75 | 9,000 | 12,000 | 17,000 |
C | 0.05 | 8.8 | 120 | 18,000 | 23,000 | 35,000 |
Pessimistic | Workload (hrs.) | Capacity (hrs.) | No. of m/c | No. of m/c rounded up | ||
A | 910 | |||||
B | 2,340 | |||||
C | 2,220 | |||||
Total | 5,470 | 2,912 | 1.88 | 2 | ||
Expected | Workload (hrs.) | Capacity (hrs.) | No. of m/c | No. of m/c rounded up | ||
A | 1,105 | |||||
B | 3,120 | |||||
C | 2,837 | |||||
Total | 7,062 | 2,912 | 2.43 | 3 | ||
Optimistic | Workload (hrs.) | Capacity (hrs.) | No. of m/c | No. of m/c rounded up | ||
A | 1,755 | |||||
B | 4,420 | |||||
C | 4,317 | |||||
Total | 10,492 | 2,912 | 3.60 | 4 |
Calculations:
Macon Controls produces three different types of control units used to protect industrial equipment from overheating....
A manager is trying to decide whether to buy one machine or two. If only one machine is purchased and demand proves to be excessive, the second machine can be purchased later. Some sales would be lost, however, because the lead time for delivery of this type of machine is six months. In addition, the cost per machine will be lower if both machines are purchased at the same time. The probability of low demand is estimated to be 0.20...