National Cranberry Cooperative
The receiving plant No. 1 is facing 3 problems:
1) Too much waiting time for trucks before they can unload their berries;
2) The overtime costs are too high;
3) The grading process of the berries is inadequate.
Process Flow Diagram for wet and dry cranberries
Arrival of berries- In the process fruit, first berries are arrived on receiving plant no.1. In which, average truck delivery was 75bbls.
Capacity of Temporary Holdings- 27 bins are used for holding both dry and wet berries. In which, 1-24 holding bins will hold 250bbls of barriers each and 25-27 will held 400 bbls of berries each.
Total capacity is: [(250*24) + (400*3)]
[6000 + 1200] that is 7200 bbls.
Destoning capacity- There are 3 destoning units and capacity of each unit is 1500 bbls, so the total capacity of destoning unit is: (1500 * 3) that is 4500 bbls.
Dechaffing capacity- There are 3 dechaffing units and capacity of each unit is 1500 bbls, so the total capacity of dechaffing unit is: (1500 * 3) that is 4500 bbls per hour.
Drying Capacity- There are 3 drying units and capacity of each unit is 200 bbls, so the total capacity of drying unit is: (200 * 3) that is 600 bbls.
Milling Capacity- In this step, berries are transferred to separator building from receiving building. Two types of quality grader are used in this step first jumbo separators and other is bailey mills. For this, 3 separator units are used, in which average capacity of each unit is 400 then total capacities are 1200 bbls (400 *3).
Bulking Capacity- Berries are directly loaded into bulk trucks. There are 2 bulk stations and capacity of each station is 1000 bbls, so total bulking capacity is 2000 (1000*2).
Bagging capacity- Maximum 8000 bbls are bagged in a 12-hour period. The maximum capacity in one hour is 667 bbls (8000/12).
There are different sources of variability that are affecting NCC’s operations. First, NCC received both fresh fruit and process fruit in its business. Fresh fruit is a labor-intensive process that uses more than 400 workers during a peak season. Process fruit is a highly mechanized process that uses different processes. There is no problem with fresh fruit processing, while it faced some problems in process fruit processing such as waiting time on unload process, increasing cost of trucks etc. (National Cranberry Cooperative, 1983). NCC also used two types of harvesting system in this business such as water harvesting and dry harvesting. Water harvesting generates 20% more yield in the business as compare to dry harvesting. It is also considerable that wet berries are directly sent to dechaffing units, while for dry berries, destoning process is necessary before dechaffing process (National Cranberry Cooperative, 1983). These are some variable sources that are used by NCC and that affect the NCC’s business operation and its effectiveness.
Assuming a berry arrival at a constant rate of 18,000 bbl a day (7am– 7pm), the average wet berry arrival rate would be 1050 bbl/ ((18,000/12)x70%) and the average dry berry arrival rate would be 450 bbl/h ((18,000/12)x30%).
The processing time starts at 11am so the holding bins will continue to be filled from 7 am till 11am to the maximum capacity of 3200 bbl for wet berries and 4000 bbl for dry berries. After 3.03 minutes (3200 / 1050) at 3.03 am, the holding bins capable to hold wet berries will be filled completely. The trucks carrying wet berries will have to wait after that. The bins holding dry berries would not be filled in this time period (450 x 4 = 1800 bbl).
When the processing starts at 11am, the wet berry processing rate would be 600 bbl/h (since they are bulked packed). However, the arrival rate continues to be 1050bbl/h, causing the trucks to queue up till 7 pm.
Total quantity of...