Concept explainers
As part of a major plant renovation project, the industrial engineering department has been asked to balance a revised assembly operation to achieve an output of 240 units per eight-hour day. Task times and precedence relationships are as follows:
Do each of the following:
a. Draw the precedence diagram.
b. Determine the minimum cycle time, the maximum cycle time, and the calculated cycle time.
c. Determine the minimum number of stations needed.
d. Assign tasks to workstations on the basis of most following tasks. Use shortest processing time as a tiebreaker. If ties still exist, assume indifference in choice.
e. Compute the percentage of idle time for the assignment in part d.
Trending nowThis is a popular solution!
Chapter 6 Solutions
Loose-leaf for Operations Management (The Mcgraw-hill Series in Operations and Decision Sciences)
- The City Commission of Nashville has decided to build a botanical garden and picnic area in the heart of the city for the recreation of its citizens. The precedence table for all the activities required to construct this area successfully is as follows: Code Description A BCDEFGH G I Find location; determine resource requirements Requisition of lumber and sand Dig and grade Saw lumber into appropriate sizes Position lumber in correct locations Nail lumber together Put sand in and under the equipment Put dirt around the equipment Put grass all over the garden, landscape, paint Time (hrs) 20 60 100 35 20 10 20 30 Immediate Predecessor(s) None A A B D, C E F F- G, H Refer to the legend for the activity that corresponds to each code. Using the line drawing tool, draw a Gantt chart for activities E through I of the project.arrow_forwardA company is setting up an assembly line to produce 90 units per hour. The table below identifies the work elements, times, and immediate predecessors. Work Element Time (Sec.) Immediate Predecessor(s) A 25 - B 18 A C 20 A D 5 B, C E 12 C F 8 E G 16 D, F H 12 G What cycle time is required to satisfy the required output? What is the theoretical minimum number of stations?arrow_forwardAn assembly line is to operate eight hours per day with a desired output of 200 units per day. The following table contains information on this product’s task times and precedence relationships: TASK TASK TIME(SECONDS) IMMEDIATEPREDECESSOR A 60 — B 60 A C 50 A D 70 A E 30 B, C F 110 C, D G 70 E, F H 70 G b. What is the required workstation cycle time to meet the desired output rate? (Round your answer to the nearest whole number.) c. Balance this line using the longest task time. (Leave no cells blank - be certain to enter "0" wherever required.) d. What is the efficiency of your line balance, assuming it is running at the cycle time determined in part b? (Round your answer to 1 decimal place.)arrow_forward
- a. Draw the precedence diagram for the processesb. Design a process layout with minimum number of workstations that would achieve thedaily production target without violating the precedence constraints c. Is it possible to issue a card per applicant every 5 minutes and why? d. How efficient is your line? e. Determine the balance delayarrow_forwardA manufacturing company is designing an assembly lineto produce its main product. Th e line should be able to produce60 units per hour. Th e following data in Table 10-16 give thenecessary information. (a) Which task is the bottleneck?(b) Draw a precedence diagram for the above information.(c) Compute the cycle time with a desired output of 60 unitsper hourarrow_forwardA manager wants to assign tasks to workstations as efficiently as possible and achieve an hourly output of 331/3 units. Assume the shop works a 60-minute hour. Assign the tasks shown in the accompanying precedence diagram (times are in minutes) to workstations using the following rules: A. In order of most following tasks. Tiebreaker: greatest positional weight. Work Station Task I II III IV b. In order of greatest positional weight. Tiebreaker: most following tasks. Work Station Tasks I II III IV c. What is the efficiency? (Round your answer to 2 decimal places.) Efficiency _________%arrow_forward
- The desired daily output for an assembly line is 360 units. This assembly line will operate 690 minutes per day. The following table contains information on this product's task times and precedence relationships: TASK TIME IMMEDIATE TASK (SECONDS) PREDECESSOR 30 55 A 50 A 55 E 35 100 G 60 E-F 45 D-G b. What is the required workstation cycle time to meet the desired output rate? Workstation cycle time seconds per unitarrow_forwardAn assembly line must be designed to produce 40 containers per hour. The following data give the necessary information Table 1 TASK IMMEDIATE PREDECESSOR TASK TIME (sec) A None 60 B A 12 C B 35 D A 55 E D 10 F E 50 G F, C 5 Draw the precedence diagram. Compute the cycle time (in seconds) to achieve the desired output rate. What is the theoretical minimum number of stations? Assign the tasks to the workstation? What is the efficiency of the line? Calculate the idle timearrow_forwardFrancis Johnson’s plant needs to design an efficient assembly line to make a new product. The assembly line needs to produce 15 units per hour, and there is room for only four workstations. The tasks and the order in which they must be performed are shown in the following table. Tasks cannot be split, and it would be too expensive to duplicate any task. TASK TASK TIME (MINUTES) IMMEDIATE PREDECESSOR A 1 — B 2 — C 3 — D 1 A, B, C E 3 C F 2 E G 3 E What is the workstation cycle time required to produce 15 units per hour? Note: Round your answer to 1 decimal place. Balance the line to use the fewest possible workstations to meet the cycle time found in part (b). Use whatever method you feel is appropriate. What is the efficiency of your line balance, assuming the line operates at the cycle time from part (b)? Note: Round your answer to 1 decimal place.arrow_forward
- Given the following task, times, and sequence, develop a balanced line capable of operating with a I 0-minute cycle time at Dave Visser's company. a) Draw the precedence diagram.b) Assign tasks to the minimum feasible number of workstations according to the greatest time remaining (ranked positional weight) decision rule.c) What is the efficiency of the process?arrow_forwardA small assembly line for the assembly of power steering pumps needs to be balanced. Precedence diagram is shown below. The cycle time is determined to be 1.7 minutes. How would the line be balanced by choosing the assignable task having the longest task time first? Fill in the table below. If your answer is zero, enter "0". Round your answers to one decimal place. Station Tasks Total Time Idle Time 1 B,A,C,D 2 E,F 3 G,H,I Total What is the assembly-line efficiency? Round your answer to one decimal place. %arrow_forwardA DIY product manufacturing company wishes to create a ‘product’ focused layout for the manufacture of their new cordless drill. There order book requires them to produce 480 drills per eight hour day. The assembly operations for the drill and the associated information are given in the table below. Therefore the key tasks are to: Management has decided to cut down 3 seconds from each operation (operation 1 - 8) to improve overall effectiveness. (a) calculate the maximum cycle time (b) calculate the minimum number of work stations (c) produce the precedence diagram (d) produce the line design which achieves the required cycle time (e) calculate balancing lossarrow_forward
- Practical Management ScienceOperations ManagementISBN:9781337406659Author:WINSTON, Wayne L.Publisher:Cengage,Operations ManagementOperations ManagementISBN:9781259667473Author:William J StevensonPublisher:McGraw-Hill EducationOperations and Supply Chain Management (Mcgraw-hi...Operations ManagementISBN:9781259666100Author:F. Robert Jacobs, Richard B ChasePublisher:McGraw-Hill Education
- Purchasing and Supply Chain ManagementOperations ManagementISBN:9781285869681Author:Robert M. Monczka, Robert B. Handfield, Larry C. Giunipero, James L. PattersonPublisher:Cengage LearningProduction and Operations Analysis, Seventh Editi...Operations ManagementISBN:9781478623069Author:Steven Nahmias, Tava Lennon OlsenPublisher:Waveland Press, Inc.