Sue Helms Appliances wants to establish an assembly line to manufacture its new product, the Micro Popcorn Popper. The goal is to produce five poppers per hour. The tasks, task times, and immediate predecessors for producing one Micro Popcorn Popper are as follows: Task Performance time(minutes) Predecessor
A 8 -
B 10 A
C 8 A, B
D 10 B, C
E 8 C
F 4 D, E

a. The theoretical minimum number of workstations is:
b. The assignment of tasks to workstations should be:

Were you able to assign all the activities to workstations equivalent to the theoretical minimum workstation ?

c. The efficiency of the assembly line is:

Please see explanation below.

Explanation:

a. Cycle time = Production time available per hour / Units required per hour

= 60 / 5

= 12minutes

Minimum number of workstations = Sum of the task time / Cycle time

Sum of task time

= 8 + 10 + 8 + 10 + 8 + 4

= 48

The theoretical minimum number of work stations is

= 48 / 12

= 4

b. In order to assign the tasks to the work station, events that precede the task must be considered together with the time taken to complete each task.

°Task A This task is assigned to work station 1 and no task would further be assigned to work station 1, otherwise it will exceed the cycle time.

°Task B. This next task will be assigned to work station 2, no additional task will be assigned to station 2.

Task C is assigned to workstation 3, hence can no longer accept any other assigned task.

°Task D is the next task and will be assigned to work station 4, and we cannot assign any more task to work station 4.

°Task E and F will not be assigned as there are no more available stations.

Task Time Workstation

A. 8 1

B. 10 2

C. 8 3

D. 10 4

E. 8 -

F. 4 -

Please note that due to the theoretical minimum number of work station, which is 4, it will not be possible to assign task to all the workstations hence task E and F remains unassigned.

C. Efficiency of the assembly line

Efficiency ;

= Sum of task times / Actual number of work stations × cycle time

Although the actual number of required workstation is 5 but we cannot assign task E and F due to the theoretical minimum number of workstation. Therefore, additional work station will be required and there are 5 work stations in total.

= 48 ÷ (5 × 12) × 100

= 80%