Academic Integrity: tutoring, explanations, and feedback — we don’t complete graded work or submit on a student’s behalf.

Develop a solution for the following line balancing problem, allowing a cycle ti

ID: 362214 • Letter: D

Question

Develop a solution for the following line balancing problem, allowing a cycle time of 5 minutes.

Draw the precedence diagram for the set of tasks.

Calculate the theoretical minimum number of workstations.

Balance this line by assigning tasks to stations.

Does the solution have the minimum number of stations? Explain.

How much idle time is there, summed over all workstations?

What is the efficiency of this line?

Work Task

Task Time (seconds)

Task Predecessor(s)

A

70

-

B

60

A

C

120

B

D

60

-

E

240

C, D

F

100

A

G

190

E, F

Work Task

Task Time (seconds)

Task Predecessor(s)

A

70

-

B

60

A

C

120

B

D

60

-

E

240

C, D

F

100

A

G

190

E, F

Explanation / Answer

The Precedence Diagram as follows :

                                                         A

                         D

                         

                          F

                   B

                  C

                                                          E

                                                                             G

Total duration of all tasks together ( A to G )

= 70 + 60 + 120 + 60 + 240 + 100 + 190

= 840 seconds

Required cycle time = 5 minutes = 300 seconds

Therefore ,

Theoretical minimum number of workstations

= Total duration of all tasks / Cycle time

= 840/300

= 2.8 ( 3 rounded to nearest whole number )

THEORETICAL MINIMUM NUMBER OF WORKSTATIONS = 3

The line is being balanced as per following in such a way so that total duration of tasks in any workstation shall not exceed required cycle time of 300 seconds :

WORKSTATION

TASKS

DURATION (SECS)

IDLE TIME = 300 SECS - DURATION

1

A,B,C

70 + 60+ 120 + 250

300 – 250 = 50

2

D,E

60 + 240 = 300

0

3

F, G

100 + 190 = 290

300 – 290 = 10

As per above arrangement , the solution achieves minimum number of stations of 3

Total idle time for 3 workstations together = 50 + 0 + 10 seconds = 60 seconds

Efficiency of this line

=   ( Total duration of tasks ) / ( 3 x Cycle time ) x 100

= 840/ ( 3 x 300)   x 100

= 93.33 %

TOTAL IDLE TIME = 60 SECONDS

EFFICIENCY OF THE LINE = 93.33 %

                                                         A

                         D

                         

                          F

                   B

                  C

                                                          E

                                                                             G