An assembly line is to be designed to operate 7 hours per day and supply a steady

An assembly line is to be designed to operate 7½ hours per day and supply a steady demand of 300 units per day. Here are the tasks and their performance times:

Task Preceding Tasks Performance Time

(Seconds)

a – 70 b – 40 c – 45 d a 10 e b 30 f c 20 g d 60 h e 50 i f 15 j g 25 k h, i 20 l j, k 25

a. Draw the precedence diagram.

b. What is the workstation cycle time required to produce 300 units per day?

c. What is the theoretical minimum number of workstations?

d. Assign tasks to workstations using the longest operating time.

e. What is the efficiency of your line balance, assuming it is running at the cycle time from part (b)?

f. Suppose demand increases by 10 percent. How would you react to this? Assume you can operate only 7½ hours per day.