Operation Management Homework

The desired daily output for an assembly line is 540 units. This assembly line will operate 729 minutes per day. The following table contains information on this product's task times and precedence relationships:

TASK

TASK TIME (SECONDS)

IMMEDIATE PREDECESSOR

A

30

—

B

28

A

C

18

B

D

69

B

E

34

A

F

36

E

G

42

C, D

H

24

F, G

b.

What is the workstation cycle time?

  Cycle time

seconds  

c.

Balance this line using the largest number of following tasks. Use the longest task time as a secondary criterion. (Leave no cells blank - be certain to enter "0" wherever required.)

Workstation

Task  

Idle Time

I

II

III

IV

d.

What is the efficiency of your line balance? (Round your answer to 2 decimal places.)

  Efficiency

%  

Some tasks and the order in which they must be performed according to their assembly requirements are shown in the following table. These are to be combined into workstations to create an assembly line. The assembly line operates 8.0 hours per day. The output requirement is 1,152 units per day.

TASK

PRECEDING TASKS

TIME (SECONDS)

TASK

PRECEDING TASKS

TIME (SECONDS)

A

—

20           

G

C

13             

B

A

7           

H

D

8             

C

A

14           

I

E

9             

D

B

16           

J

F, G

8             

E

B

15           

K

H, I

9             

F

C

14           

L

J, K

4             

a.

What is the workstation cycle time?

  Workstation cycle time

seconds per unit  

b.

Balance the line using the longest task time based on the 1,152-unit forecast, stating which tasks would be done in each workstation. (Leave no cells blank - be certain to enter "0" wherever required.)

Workstation

     Task

    Idle Time

I

II

III

IV

V

VI

c.

For b, What is the efficiency of your line balance? (Round your answer to 2 decimal place.)

  Efficiency

%  

d.

After production was started, Marketing realized that they understated demand and must increase output to 1,242 units. What action would you take? Be specific in quantitative terms, if appropriate. (Input all amounts as positive values. Round down "cycle time" value to the next smallest integer and "overtime" to nearest whole number.)

   cycle time to seconds or work minutes of overtime.

An assembly line is to be designed to operate 12 hours per day and supply a steady demand of 360 units per day. Here are the tasks and their performance times:

TASK

PRECEDING TASKS

PERFORMANCE TIME (SECONDS)

TASK

PRECEDING TASKS

PERFORMANCE TIME (SECONDS)

A

—

58

G

D

60

B

—

70

H

E

20

C

—

60

I

F

38

D

A

35

J

G

55

E

B

30

K

H, I

54

F

C

40

L

J, K

60

b.

What is the workstation cycle time?

  Cycle time

seconds/unit  

c.

What is the theoretical minimum number of workstations? (Round your answer to the next whole number.)

  Minimum number of workstations

d.

Assign tasks to workstations using the longest operating time.

Workstation

Task

Idle Time

I

II

III

IV

V

e.

What is the efficiency of your line balance? (Round your answer to 1 decimal place.)

  Efficiency

%  

f.

Suppose demand increases by 10 percent. How would you react to this? Assume that you can operate only 12.0 hours per day. (Input all amounts as positive values. Round your answers to 2 decimal places.)

   cycle time to seconds per unit. Another option is to work minutes overtime.