Problem 1: Line Balancing First shift employees at Generac work from 6am to 2pm Monday through Friday. Everyone on the assembly line is allowed a 30 minute lunch and two 20 minute breaks, but other cross-trained associates cover lunches and breaks for the associates on the assembly line so the line doesn’t stop. The processes of the assembly line have the following dependencies: Task Predecessor Average Time (sec) A none 60 B A 80 C A 20 D A 40 E B 30 F D 70 G E, C 50 H F, G 10 The Plant Manager needs first shift to achieve an output of 300 generators. a) Compute the Takt time for the line. b) What is the theoretical minimum number of workstations? c) Draw the precedence diagram, and then create work stations. Follow the “largest eligible task” heuristic rule to assign these tasks to the work stations. Show which tasks are assigned to each workstation. d) Compute the efficiency and percent idle time for the system. e) What is the maximum output that could be achieved by a single assembly line in 8 hours?
Problem 2: Line Balancing (8 points) Your product has the following tasks and predecessors. Task Predecessor Average Time (sec) A none 40 B none 60 C A 30 D C 40 E B, D 30 F E 30 a) Use a takt time of 120 seconds and follow the “most following tasks” heuristic rule to assign these tasks to the work stations. Show which tasks are assigned to each workstations. b) Compute the efficiency and percent idle time for the system. Problem 3: Supplier Selection Your sourcing department has received bids from three suppliers shown below. PERFORMANCE DIMENSION IMPORTANCE Supplier 1 Supplier 2 Supplier 3 On Time Delivery (% on time) 0.40 98% 94% 93% Financial Stability (rating) 0.20 BBB AAA AA Cost ($/unit) 0.40 $10.75/unit $10.35/unit $9.99/unit a) Score each supplier‘s bid using the following scale. On Time Delivery Financial Stability Cost Range Score Rating Score Range Score <90% 1 Lower than BBB 1 >$12.00 per unit 1 91%-93% 2 BBB 2 $10.50-$11.99 per unit 2 94%-96% 3 A 3 $10.00-$10.49 per unit 3 97%-98% 4 AA 4 $9.50-9.99 per unit 4 99%+ 5 AAA 5 <$9.50 per unit 5 b) Calculate the weighted average score for each supplier.