Darsoft Inc., a large manufacturer of personal computers, assembles Intel Core Duo motherboards on a product line. According to the production technology, the tasks that must be performed on each motherboard are shown below. Production quotas require that 120 completed units be assembled in a 12-hour shift.
Task Description Predecessor Time (minutes)
A Assemble motherboard frame none 3
B Install circuit board #1 A 4
C Install circuit board #2 A 2
D Install controller A 2.5
E Install hard drive B,C 2
F Install disk drives D,E 3
G Install power supply E 4
H Install motherboard cover F,G 2
I Final quality check H 4.5
Questions.
1. Explain why the line balancing approach may be used for this case.
2. Develop precedence diagram for this case in Excel or Word, identify cycle time and minimum number of workstations.
3. Using the rule of the longest task (operation) time, identify and present assignments of tasks to the workstations.
4. Identify efficiency and idleness of the process and explain what they mean.