FACILITIES LAYOUT FOR FLOW MANUFACTURING

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FACILITIES LAYOUT FOR FLOW MANUFACTURING

•  Product Layouts
• Determining The Cycle Time
• Line Balancing The Lot Rule
• Group Technology And Cellular Manufacturing

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PRODUCT LAYOUTS

• Objective assign tasks to workstations so as to
  maximize the utilization of each workstation
• Difficulty arises due to
• Discrete nature of elemental tasks
• Precedence constraints
• How much wasted time per unit for this layout if
  each task is performed at a different workstation?

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PRODUCT LAYOUTS

• Notation
• M -- number of elemental tasks
• Ti -- time for ith task
• N -- number of workstations
• CT -- cycle time (minutes/unit)
• BD -- balance delay ( idle time)

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BALANCE DELAY
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FINDING THE CYCLE TIME

• The cycle time (minutes/unit) is the inverse of
  speed of the line (units/minute)
• To find the cycle time, we need the target output
  rate
• Define
• D -- target output rate (units/day)
• OT -- operating time per day (minutes/day)

• Example we want to make 800 units a day and run
  the line 2 8-hour shifts each day.

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THE PRECEDENCE DIAGRAM

• The precedence diagram is a visual representation
  of the the elemental tasks and their
  interrelationships
• Similar to a flow process chart

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LINE BALANCINGTHE LOT RULE

• 1) Determine cycle time of line
• 2) Define the current workstation as workstation
  1
• 3) If no more tasks exist, stop. If no
  candidate task exists for the current
  workstation, go on to the next workstation.
• 4) Pick the longest candidate task for placement
  at the current workstation.
• 5) Go to step 3

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LINE BALANCING EXAMPLE

• CT 1.2 Minutes

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LINE BALANCING EXAMPLE

• CT 1.2 Minutes

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LINE BALANCING EXAMPLE

• CT 1.2 Minutes

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LINE BALANCING EXAMPLE

• CT 1.2 Minutes

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LINE BALANCING EXAMPLE

• CT 1.2 Minutes

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LINE BALANCING EXAMPLE

• CT 1.2 Minutes

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LINE BALANCING EXAMPLE

• CT 1.2 Minutes

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LINE BALANCING EXAMPLE

• CT 1.2 Minutes

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LINE BALANCING EXAMPLE

• CT 1.2 Minutes

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LINE BALANCING EXAMPLE

• CT 1.2 Minutes

Excel
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GROUP TECHNOLOGY AND CELLULAR MANUFACTURING

• Attempts to combine best of flow shop and job
  shop
• Group technology identifies product families 
• Each family has a dedicated cell