ROUGHCUT CAPACITY PLANNING

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ROUGH-CUTCAPACITY PLANNING

• Validating The MPS (Sort Of)
• Bills Of Materials Routings
• Capacity Planning Using Overall Factors
• Capacity Bills
• Picking A RCCP Technique

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CORE MRP II
MANUFACTURING RESOURCE PLANNING
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VALIDATING THE MPS (SORT OF)

• Need to ensure that MPS is feasible
• MPS must not require more capacity then is
  available
• Use rough-cut capacity planning techniques to
  estimate capacity needs in each workcenter
•  Labor requirements
•  Machine requirements
• Compare capacity needed to planned available
  capacity
• Adjust MPS if workcenters are overloaded

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VALIDATING THE MPS (SORT OF)

• RCCP eliminates MPS's which drastically overload
  some workcenters
• Low computational expense
• Rapid calculation for what-if analysis
• Not 100 accurate
• Does not use material plans
• All RCCP ignores actual lot-sizing, beginning
  inventory, work-in-process

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VALIDATING THE MPS (SORT OF)

• Information requirements for all RCCP techniques
• Bills of Materials (BOMs)
• Show how products are put together
• Routings
• Show where products and component parts are made

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BILLS OF MATERIALS

• BOM's show how parts combine to create a product
• Representation may be graphical

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BILLS OF MATERIALS

• Indented BOMs are common as computer printouts
• X
• A
• B
• A
• Y
• B(2)
• A

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ROUTINGS

• A routing lists the
•  Operations necessary to make a part
•  Workcenters where the operations are performed
• The routing also lists the expected capacity
  needed at each operation
•  Per setup
•  Per unit

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STANDARD TIMES

• A standard time per unit includes the runtime and
  an allocated portion of the setup time
• Standard times assume an average lot size
• Used in RCCP since actual lot sizes for parts
  ignored

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CAPACITY PLANNING USING OVERALL FACTORS

• Simplest and least accurate RCCP method
• For N products, W workcenters, and a planning
  horizon of T periods, requires only N W 1 rows
  and T columns in a spreadsheet
•  
• Ignores current product mix, lead times
• Therefore appropriate if lead time is short and
  product mix is steady over time

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CAPACITY PLANNING USING OVERALL FACTORS

• Determine cumulative standard times for each
  product
• Apply cumulative standard times from (1) to MPS
  to determine total required capacity per period
  for facility
• Determine planning factors expressing of
  facilty capacity historically used in each
  workcenter
• Apply planning factors from (3) to facility
  capacity from (2) to determine capacity
  requirements per period for each workcenter

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CUMULATIVE STANDARD TIMES

• The Cumulative Standard Time is the time required
  to make a unit of a part from scratch
• STi,j Incremental standard time to make part i
  in workcenter j
• CSTi,j Cumulative standard time to make part i
  and all component parts in workcenter j
• CSTi Cumulative standard time to make part i
  and all component parts in all workcenters

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CUMULATIVE STANDARD TIMES
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CUMULATIVE STANDARD TIMES
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CUMULATIVE STANDARD TIMES
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CAPACITY PLANNING USING OVERALL FACTORS

• Determine cumulative standard times for each
  product CSTX 2.05 CSTY 4.60

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CAPACITY PLANNING USING OVERALL FACTORS

• 2. Apply cumulative standard times from (1) to
  MPS to determine total required capacity per
  period for facility CSTX 2.05 CSTY 4.60

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CAPACITY PLANNING USING OVERALL FACTORS

• 2. Apply cumulative standard times from (1) to
  MPS to determine total required capacity per
  period for facility CSTX 2.05 CSTY 4.60

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CAPACITY PLANNING USING OVERALL FACTORS

• Determine planning factors expressing of
  facilty capacity historically used in each
  workcenter
• Workcenter W101 70
• Workcenter W102 30

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CAPACITY PLANNING USING OVERALL FACTORS

• 4. Apply planning factors from (3) to facility
  capacity from (2) to determine capacity
  requirements per period for each workcenter
• Workcenter W101 70
• Workcenter W102 30

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CAPACITY PLANNING USING OVERALL FACTORS

• 4. Apply planning factors from (3) to facility
  capacity from (2) to determine capacity
  requirements per period for each workcenter
• Workcenter W101 70
• Workcenter W102 30

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CAPACITY PLANNING USING OVERALL FACTORS

• 4. Apply planning factors from (3) to facility
  capacity from (2) to determine capacity
  requirements per period for each workcenter
• Workcenter W101 70
• Workcenter W102 30

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CAPACITY BILLS

• Slightly more computationally complex and more
  accurate than CPOF
• For N products, W workcenters, and a planning
  horizon of T periods, requires N(W 1) 1 rows
  and T columns in a spreadsheet
•  
• Ignores lead times
• Therefore appropriate if lead time is short

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CAPACITY BILLS

• Determine cumulative standard times per
  workcenter for each product
• Apply cumulative standard times per workcenter
  from (1) to MPS to determine capacity
  requirements per period for each workcenter

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CUMULATIVE STANDARD TIMES
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CAPACITY BILLS

• Determine cumulative standard times per
  workcenter for each product
• CSTX,W101 1.25
• CSTX,W102 0.80
• CSTY,W101 3.00
• CSTY,W102 1.60

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CAPACITY BILLS

• 2. Apply cumulative standard times per workcenter
  from (1) to MPS to determine capacity
  requirements per period for each workcenter
• CSTX,W101 1.25 CSTX,W102 0.80 CSTY,W101
  3.00 CSTY,W102 1.60

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CAPACITY BILLS

• 2. Apply cumulative standard times per workcenter
  from (1) to MPS to determine capacity
  requirements per period for each workcenter
• CSTX,W101 1.25 CSTX,W102 0.80 CSTY,W101
  3.00 CSTY,W102 1.60

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CAPACITY BILLS

• 2. Apply cumulative standard times per workcenter
  from (1) to MPS to determine capacity
  requirements per period for each workcenter
• CSTX,W101 1.25 CSTX,W102 0.80 CSTY,W101
  3.00 CSTY,W102 1.60

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CAPACITY BILLS

• 2. Apply cumulative standard times per workcenter
  from (1) to MPS to determine capacity
  requirements per period for each workcenter
• CSTX,W101 1.25 CSTX,W102 0.80 CSTY,W101
  3.00 CSTY,W102 1.60

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CAPACITY BILLS

• 2. Apply cumulative standard times per workcenter
  from (1) to MPS to determine capacity
  requirements per period for each workcenter
• CSTX,W101 1.25 CSTX,W102 0.80 CSTY,W101
  3.00 CSTY,W102 1.60

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PICKING A RCCP TECHNIQUE

• Stable demand and product mix?
• Use CPOF
• Changing mix but short lead times?
• Use capacity bills
• Changing mix and long lead times?
• Use resource profiles
•