Assembly Line Balancing

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Assembly Line Balancing
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Assembly Operation
Assembly operation is the process of combining
the parts of a product in a systematic and
orderly fashion. One of the important tasks in
manufacturing environment is to design assembly
lines in such a way that the demand for the
products are met and the productivity of the
assembly line is maximized.
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Example
Consider a product whose assembly process
involves 11 tasks whose immediate predecessors
and times are listed in the table below.
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Precedence Diagram


1 8
3 6
7 10 11
2 4 5
9
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Desired Cycle Time
suppose that a production rate of 1,300 units per
day is desired. And the factory will operate
three shifts per day. Therefore, operating three
shifts per day at a 90 percent efficiency amounts
to approximately (1,300/3) 433 units per shift
productive capacity. To estimate the required
cycle time we first compute the productive hours
for each shift. This is (8 hours per shift)(0.9
efficiency) 7.2 hours per shift. Thus, the
desired cycle time is given by C (7.2 hrs.
per shift)x(60 min. per hour)/(number of units
per shift required) C (7.2)x(60)/433 0.9977
min.
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Assembly Line Balancing Heuristic
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Assembly Line Balancing Heuristic
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Assembly Line Balancing Heuristic
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Assembly Line Balancing Heuristic
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Assembly Line Balancing Heuristic
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Assembly Line Balancing Heuristic
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Station Assignment
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Efficiency
Line efficiency (0.70.91.00.70.90.6)/(1.0
)x(6) 0.80 Therefore, this line will operate
at 80 percent efficiency and it will stay idle 20
percent of the time.