A Small Electronics Company Assembles Power Supplies for Use in Computers

Essay

A small electronics company assembles power supplies for use in computers, printers and Fax machines. They want to set up an assembly line to make their operation more efficient and plan to use line balancing with the longest-task-time heuristic. The demand for power supplies is 70 per hour, and the productive time per hour is 52 minutes. The following table provides details on their operation.
$\begin{array}{ccc}\text { Task } & \text { Time in minutes) } & \text { Predecessors } \\\text { A } & .54 & \text { none } \\\text { B } & .34 & \mathrm{~A} \\\text { C } & .11 & \mathrm{~A} \\\mathrm{D} & .09 & \mathrm{~A} \\\mathrm{E} & .43 & \mathrm{~B}, \mathrm{C} \\\mathrm{F} & .22 & \mathrm{D} \\\mathrm{G} & .62 & \mathrm{E} \\\mathrm{H} & .35 & \mathrm{~F}, \mathrm{G} \\\mathrm{I} & .21 & \mathrm{H} \\\mathrm{J} & .57 & \mathrm{H} \\\mathrm{K} & .33 & \mathrm{I}, \mathrm{J}\end{array}$

a. What is the cycle time?
b. What is the theoretical minimum number of workstations?
c. What tasks go into the first workstation?
d. How many workstations are needed for the entire line?
e. What is the assembly-line efficiency?