seminar l b

8/8/2019 seminar L B

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HIMANSHU VARUN CANDRAKAR

ROLL NO 214110019

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` Introduction` Objectives

` Origin of line balancing

` Factors responsible for line balancing.

` Advantages and disadvantages.` Termonology

` Important parameters

` Steps of generalized algorithm

` Different method of line balancing problem

` Kilbridge and wester heuristics

` Solved example

` Balance of line in variety of ways

` References

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` For smooth and efficient working of the assembly

line every work station should be assigned with

equal amount of work measured in terms of time

units, and this process of apportioning theassembly work among the operators is known as

assembly-line balancing.

` Line balancing is mainly associated with productlayout or flow shops.

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V1


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Slide 4

V1 V@RUN, 10/5/2010


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` To subdivide the station into several sub stations.

` Precedence relationships must be maintained

during allocating operations.

` To minimizes the total idle time.` To optimize the congestion.

` It ensures that the stages of production are co-

ordinated and bottleneck are avoided.

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` Although the first assembly line was set up as early as

1913.

` Henry Ford was the pioneer in starting the first

assembly line for car manufacturing.` The line-balancing problem is probably the most

complicated problem faced by the engineer when

designing a production line.

` Recently this problem of line balancing has been

formulated analytically, and has drawn the attention of

those concerned with the science of management.

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` If finished product is the result of many sequential

problem.

` Difference in production capacity of differentmachines.

` Cycle time required for workstation.

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ADVANTAGES

` Uniform rate of production.

` Less work-in-process.

` Easy production control.

` Effective use of facilities.

` Less bottle necking.

DISADVANTAGES

` More capital intensive.` Low flexibility.

` Monotony of work for operators.

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` Workstation

` Cycle time(C.T.)

C.T. =

` Work element

` Predecessor element

` Task time(t)- Standard time to perform

element task.` Station time(T)- Total standard work content

of specific workstation.

Productive time period

Production volume per period

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` Line efficiency (L.E.)

L.E.= =

` Balance delay (B.D.)B.D. = 1 L.E.

total station time

C.T. no. of workstation

100 t

i=1

N

i

C.T. k

100

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` Smoothness Index (S.I.)

S.I. = {(Max. station time station time of station i ) }

If S.I. = 0, means a perfect balance

k = total no of workstation


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Input: cycle time (C.T.),

precedence matrix,

total number of work elements(M),

work element times.

Initialize: unassigned cycle time(UACT) = CT,

station number (WS=1)

total number of assigned work element(N)=1

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1) Print the station number(WS).

2) Initialize the total number of assigned work element counter to one, i.e. i=1.

3) If the i th work element is not assigned and all immediate precedors of the i

th work element are assigned or no immediate precedors, then go to step4,

otherwise go to step 6.

4) If the i th work element time is less than or equal to the unassigned cycle

time(UACT), then go to step5, otherwise go to step6.

5) Include the i th work element in the list A.

6) Increment the total number of assigned work elements counter by one, i.e. i

=i +1

7) Ifi M, then go to step 3; otherwise go to step 8.

8) If the number of work elements in the list A is more than 0,then go to step

10; otherwise go to step 9.

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9) Perform the following and then go to step 2.a) Update UACT = CT

b) Update WS = WS+1

c) PrintWS

10) If the number of work element in the list A is equal to one, then assign that

work element to the current station; otherwise select a work element from

list A using a given HEURISTIC.

11) Subtract the recently assigned work element time from UACT and print the

recently assigned work elements number.

12) Update N =N +1

13) If N M, then go to step 2; otherwise go to step 14

14) Compute B.D. in percentage.15) Stop.

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7 8

9 12

1110

6

54

32

1

5

43

3 6

5 1

4 4

2 6

7

Work element

Element time

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Station no. List A Work element assigned UACT

1 - - 11

1 1 6

2,4 4 32,5 2 0

2 - - 11

3,5 3 7

5,6 5 1

- - 1

3 - - 11

6 6 6

7,9,10 10 2

7,9,11 7 0

4 - - 11

8,9,11 8 5

9,11,12 11 1

9,12 9 0

5 - - 11

1) Print the station number(WS).

2) Initialize the total number of assigned work element counter to one, i.e. i=1.

3) If the i th work element is not assigned and all immediate precedors of the i

th work element are assigned or no immediate precedors, then go to step4,otherwise go to step 6.

4) If the i th work element time is less than or equal to the unassigned cycle

time(UACT), then go to step5, otherwise go to step6.

5) Include the i th work element in the list A.

6) Increment the total number of assigned work elements counter by one, i.e. i

=i +1

7) Ifi M, then go to step 3; otherwise go to step 8.

8) If the number of work elements in the list A is more than 0,then go to step

10; otherwise go to step 9.

9) Perform the following and then go to step 2.

a) Update UACT = CT

b) Update WS = WS+1

c) PrintWS

10) If the number of work element in the list A is equal to one, then assign that

work element to the current station; otherwise select a work element from

list A using a given HEURISTIC.

11) Subtract the recently assigned work element time from UACT and print the

recently assigned work elements number.

12) Update N =N +113) If N M, then go to step 2; otherwise go to step 14

14) Compute B.D. in percentage.

15) Stop.

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7 8

9 12

1110

6

54

32

1

5

43

3 6

5 1

4 4

2 6

7

Work element

Element time

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7 8

9 12

1110

6

54

32

1

5

43

3 6

5 1

4 4

2 6

7

1 2 3 4 5 6 7

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t C.T. t

t = 7

t =5+3+4+3+6+5+2+6+1+4+4+7

= 50

7 C.T. 50

C.T. = =

=10.9 11

max

max

i=1

i=1

N

N

i

i

Productive time period

Production volume per period

8 60

44

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7 8

9 12

1110

6

54

32

1

5

43

3 6

5 1

4 4

2 6

7

WS-1WS-2 WS-3 WS-4 WS-5

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WORKSTATION 1 2 3 4 5

TIME (min) 11 10 11 11 7

Line efficiency = =

= 90.9%

Smoothness index = {(Max. station time station time of station i ) }

= { (11-11) + (11-10) + (11-11) + (11-11) + (11-7) }

= 4.123

t ii=1

N

C.T. k 100

11 5

50

1/22

i=1

k

2 2222 1/2

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Balance delay = 1 L.E. = 1-O.909

= 0. 091

i.e. 9.1%

Idle time = (11-11) + (11-10) + (11-11) + (11-11) + (11-7)

= 5

Idle time % = (5/11) 100

= 45.45%

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` Diamond star motor automobile manufacturing facility has achieved

balanced assembly lines through traditional analysis combined with a highly

automated material system.

` Sun micro system has expended production facility balances lines with a

more modular approach using torque conveyor to drive the materialhandling system.

` At asheville,Westinghouse has five separate assembly lines balanced by

one common feeder mini plant and one master storeroom.

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` A Comparative Evaluation of Assembly Line BalancingHeuristics, by S. G Ponnambalam, P. Aravindan 2 and G.Mogileeswar Naidu.

` A survey on problems and methods in generalized assembly

line balancing, by Christian Becker and Armin Scholl.

` Industrial engineering and production management, bymartand telsang.

` Production and operation management, by R. paneerselvam.

` A Genetic Algorithm for Bin Packing and Line Balancing, byE.Falkenauer and A.Delchambre.

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seminar l b

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