National Cranberry Cooperative (NCC) is an organization, formed and owned by growers of cranberries to process and market berries. During the cranberry harvest season, trucks bring wet berries from the fields to the processing plant during a workday that runs from 6 AM to 6 PM. Employees work in two shifts-the first from 6 AM to 2 PM and the second from 2 PM to 10 PM. Employees who work more than 8 hours per day receive overtime payment of 50% more than the base rate. Prevailing base wage rate is $ 10 per hour. On peak days, approximately 18,000 bbls (barrels) of berries are trucked per day. The table below shows the arrival information of wet berries during a typical peak day.
Time Berries Arrived (in bbls)
6 AM-7 AM 800
7 AM-8 AM 800
8 AM-9 AM 1,100
9 AM-10 AM 1,900
10 AM-11 AM 2,100
11 AM-12 PM 2,500
12 PM-1 PM 1,000
1 PM-2 PM 2,000
2 PM-3 PM 1,400
3 PM-4 PM 1,300
4 PM-5 PM 1,000
5 PM-6 PM 1,000
Trucks carry 100 bbls on average. Trucks dump their contents in 12 holding bins. Each holding bin has a storage capacity of 250 bbls. When the bins are full, incoming trucks must wait until it has sufficient available space. A conveyor moves berries from the bin to the processing plant. The plant starts its operation as soon as berries arrive. The first process in processing plant after dumping is dechaffing. NCC has three dechaffing machines. Each dechaffing machine can process 1,000 bbls per hour. The second process is drying. NCC has one dryer with 750 bbls/hr of processing capacity. The final process is packing and they have three packing machines. Total processing capacity of the three different packing machines is 3,000 bbls per hour (i.e. each packing machine can process 1,000 bbls per hour).
a. Draw a process flow diagram and find the process bottleneck.
b. Find when does truck queuing start?
c. How many hours of overtime work are necessary?
d. How would you streamline the process to avoid the truck queuing? At what cost? A dryer costs $75,000, a dechaffing machine $ 30,000, a packing machine $ 5,000 and a holding bin costs $5,000. Show at least two possible alternatives and recommend one.