Homework 6a Operations

Justin Prater Chapter 6A 3, 4, 9, and 14 3) a. b. Cycle sentence = production time per twenty-four hours/required output per day = (8 hour/day)(3600 seconds/hour)/240 units per day = 120 seconds per unit c. Work station assign Task time Idle time I AD 6050 10 II BC 8020 20 III EF 9030 0 IV GH 3060 30 d. Efficiency = Task time / stations X avg. bi hertz time) = = . 875 or 87. 5% 4) a. A B F C D E G 30 35 15 65 H 30 35 40 25 A B F C D E G 30 35 15 65 H 30 35 40 25 b. What is the workstation cycle time? Cycle time = production time per day/required output per day Cycle time = 27000 / 360 = 75 seconds. . figure this balance inventory using the largest number of following toils. Use the longest task time as a secondary criterion. 275 / 75 = 3. 66 in that location should be a minimum of 4 work stations Work station Task Task time Idle time I sense experience 303015 0 II BD 3535 5 III F 65 10 IV GH 4025 10 d. What is the readiness of your balance line? 91. 7% 9. A B F C D E G 20 7 15 10 H 20 22 16 8 A B F C D E G 20 7 15 10 H 20 22 16 8 a. Cycle time = production time per day/required output per day Cycle time = 25200 / 750 = 33. 6 seconds. b. What is the theoretical number of workstations? workstations = sum of task times / cycle time 118 / 34 = 3. 5 There is a minimum number of 4 workstations. c. Draw the precedence diagram d. Balance the line using sequential restrictions and the longest-operating time rule. Work station Task Task time Idle time Feasible Rem. T. Tasks w/ most foll Task w/ longest t. I AB 207 147 B B B II DF 2210 122 F F F III C 20 14 IV EG 1516 193 G G G V H 8 26 e. What is the efficiency of the line balanced as in d? Efficiency = add up of task times / ( workstations X Cycle time) = 118 / (5 X 34) = . 70Efficiency = 70% f. Suppose that demand rose from 750 to 800 units per day. What would you do? Show all amounts or calculations. New cycle time = 25200/800 = 31. 2 seconds Reduce cycle time to 31 seconds and work 62-3 min ute overtimes. g. Suppose that demand rose from 750 to 1000 units per day. What would you do? Show any amounts or calculations. New cycle time = 25200/1000 = 25. 2 seconds 1. 89 hours overtime may be better to rebalance. 14) Develop two alternative layouts. What is the efficiency of your layouts? A B F C D E G 1 1 3 1 H 2 1 1 2 1 I A B F C D E G 1 1 3 1 H 2 1 1 2 1 I Cycle time = 4 minutesWhat is the theoretical number of workstations? workstations = sum of task times / cycle time 13 / 4 = 3. 25 Work station Task Task time Idle time Feasible Rem. T. Tasks w/ most foll Task w/ longest t. I ABC 11 2 32 0 B,F C,D B C,D B,F C IIIIIIV DEFGHI 131121 303203 EGH EGH EGH Work station Task Task time Idle time Feasible Rem. T. Tasks w/ most foll Task w/ longest t. I AFG 11 1 32 1 B,F G B G B,F G IIIIIIV BCDEHI 311321 313021 C,DEI C,DEI C,DEI