Capacity Requirements Planning (CRP)

This chapter covers the following topics:

Overview of Capacity Requirements Planning

CRP verifies that you have sufficient capacity available to meet the capacity requirements for your MRP plans.

CRP is a shorter term capacity planning tool than rough cut capacity planning (RCCP). Like RCCP, CRP is used by marketing and production to balance required and available capacity, and to negotiate changes to the master schedule and/or capacity requirements.

CRP is a more detailed capacity planning tool than rough cut capacity planning in that it considers scheduled receipts and on-hand inventory quantities when calculating capacity requirements. Your detailed capacity plans are therefore a statement of the capacity required to meet your net production requirements.

As with RCCP, you can perform detailed capacity planning at two levels. If you want to plan detailed capacity by resource, then you should use routing-based CRP. Required and available capacity are stated in hours per week per resource.

If you prefer to plan your detailed capacity by production line, use rate-based CRP. Required and available capacity are stated by production rate per week per line.

If you wish to use CRP, but would like to restrict the process to key or critical resources, you can define groups of selected resources and review CRP plans for specific resource groups only. You can define your resource groups in Oracle Capacity and Oracle Bills of Material. You can assign resources to resource groups in Oracle Bills of Material.

You can also create a routing for a product family item.

Routing-Based CRP

Routing-based CRP calculates and compares required capacity to available capacity for the individual resources you assign to operations on your routings.

Required and available capacity are stated in hours per week per resource.

Required Hours Calculation

Unlike routing-based RCCP, which uses master schedule quantities and bills of resources to calculate capacity requirements, routing-based CRP calculates capacity requirements using the dates and quantities generated by the planning process. Total requirements are calculated by summing the requirements generated by:

Required Hours for Planned Orders and Repetitive Schedules

For planned orders for items that use Item basis resources, routing-based CRP calculates required hours using the following formula:

required hours = runtime quantity x order quantity



Routing-based CRP treats repetitive schedules as if they were planned orders for each day in the period spanned by the schedule start and end dates. Thus, for the repetitive schedules, order quantity is the suggested daily rate.

For planned orders for items that use Lot basis resources, routing-based CRP calculates required hours using the following formula. Notice that for Lot basis resources, the order quantity has no impact on required hours.

required hours = runtime quantity

The following table shows four plan entries for C, and illustrates how, for each entry, routing-based CRP calculates required hours and dates for D1, R2. Using resource requirements loaded from Oracle Bills of Material - Oracle Capacity determined that 8 hours of D1, R2 are required to build one unit of C, and that the resource offset for D1, R2 is 0.5. See: Bill of Resources Example, Assume a lead time of 2 days for building C. In this example, 18 units of C are required on 03-FEB. These 18 units represent derived demand from the discrete job for 6 units of A due on 07-FEB. Routing-based CRP calculates the required hours for D1, R2 as 18 x 8 = 144 hours. Routing-based CRP calculates the required date as 03-FEB - (2 x (1 - 0.5)) = 03-FEB - 1 = 02-FEB. 05-FEB and 06-FEB are non workdays.

Required Hours and Dates for D1, R2
Item Plan Date Plan Qty Required Hours Required Date
A 03-Feb 18 144 02-Feb
A 03-Feb 12 96 02-Feb
A 08-Feb 30 240 07-Feb
A 11-Feb 30 240 10-Feb

The following table illustrates how routing-based CRP uses required dates to bucket the required hours for D1, R2 into weekly buckets. The example assumes that the first bucket starts on 31-JAN.

Bucketed Required Hours and Required Dates for D1, R1
Week Start Date Department Resource Required Hours
31-Jan D1 R2 240
07-Feb D1 R2 480

Routing-based CRP treats suggested repetitive schedules as if they were planned orders for each workday between the schedule start date and the schedule end date, and calculates required hours and required dates using the same calculations illustrated in the previous example.

Required Hours for Discrete and Non-Standard Jobs

Routing-based CRP calculates required hours for discrete and non-standard jobs using the following formula:

total hours = required hours - expended hours

Since the Snapshot loads operation start dates directly from Oracle Work in Process, required dates are already known and there is no need for routing-based CRP to calculate them.

Oracle Capacity calculates required hours and dates for all discrete and non-standard jobs, and adds them to the required hours and dates calculated for planned orders and repetitive schedules for each resource.

Available Hours Calculation

Like routing-based RCCP, routing-based CRP calculates available hours using the resource availability information you define in Oracle Bills of Material.

You can define resources, departments, shifts, and shift calendars in Oracle Bills of Material. Having defined your departments, resources, and shifts, you can assign shifts to resources and resources to departments.

Routing-based CRP calculates available hours for a resource by summing the available hours for each shift that uses the resource using the following formula:

available hours = capacity units x shift hours per

day x shift days per week x efficiency x utilization

For 24-hour resources, routing-based CRP modifies the formula as follows:

Available hours = capacity units x 24 hours per day x workdays per week x efficiency x utilization

Capacity units represents the number of resource units available to a department. Shift hours per day and shift days per week reflect the availability times you specify for each shift in Oracle Bills of Material. Workdays per week reflect the number of workdays in the week based on the workday calendar you define in Oracle Bills of Material.

The following table illustrates how routing-based CRP would calculate available hours for D1, R2, assuming that you have assigned it to two shifts, Shift 1 and Shift 2. In this example, the available hours for D1, R2 on Shift 1 is 2 x 6 x 5 = 60 hours. Routing-based CRP would calculate the total hours available for D1, R2 as 60 + 80 = 140 hours per week.

Available Hours for D1, R2
Shift Capacity Unit Shift
Hours/Day
Shift
Days/Week
Available Hours
Shift 1 2 6 5 60
Shift 2 2 8 5 80

Load Ratio Calculation

Routing-based CRP calculates capacity load ratio for each resource by dividing the total required hours per week by the total available hours per week, using the following formula:

capacity load ratio = required hours / available hours



The following table illustrates how routing-based CRP would calculate capacity load ratio for D1, R2 for the weeks starting 31-JAN and 07-FEB. In the Resource Requirements Snapshot Example, the capacity load ratio for D1, R2, for the week starting 31-JAN, is 240/140 x 100% = 71%.

Capacity Load Ratio for D1, R2
Week Start Date Required Hours Available Hours Capacity Load Ratio
31-Jan 240 140 171%
07-Feb 480 140 343%

Notice that D1, R2 is overloaded for both weeks.

Rate-Based CRP

Rate-based CRP calculates and compares required capacity to available capacity for production lines rather than individual resources assigned to operations on your routings. Required and available capacity are stated in production rate per week per line.

You can associate a production line with a product family item.

Required Rate Calculation

Unlike rate-based RCCP, which uses master schedule quantities and bills of resources to determine capacity requirements, rate-based CRP calculates capacity requirements using the dates and quantities generated by the planning process.

Rate-based CRP calculates capacity requirements and availabilities for items you have defined as repetitive assemblies and assigned to production lines in Oracle Work in Process.

B and C are defined as repetitive assemblies and assigned to production lines in Oracle Work in Process.

Production Line Details for B and C
Item Line Line Priority Production Rate Max Hourly Rate Line
Hours/Day
Line
Days/Week
B Line 1 1 75 100 12 5
B Line 2 2 50 100 6 5
C Line 1 1 100 100 12 5

Line Priority

You can use line priorities to indicate your preferred production lines for building a repetitive assembly. Line priority is used by Oracle Master Scheduling/MRP’s repetitive schedule allocation process to allocate aggregate repetitive schedules to individual lines. In this example, Line 1 is the preferred line for building item B.

Production Rate

Production rate represents the maximum hourly rate that you can build an assembly on a particular line. The production rate you specify for an assembly can never exceed the maximum hourly rate specified for the production line you defined in Oracle Work in Process.

Maximum Hourly Rate

Maximum hourly rate represents the maximum production rate for a production line across all assemblies.

Rate-based CRP:

Calculates the required rate for each line by taking each suggested repetitive schedule on your MRP plan and using the repetitive schedule allocation process to allocate the planned rate across individual production lines.

Determines the required date for each rate during the gross-to-net explosion performed by the planning process.

Buckets the required rates into weekly buckets.

Note that there is no need to offset rate start and end dates since lead time offsets are applied during the planning process. The following tables show three plan entries for A.

Master Schedule for A
Item Order Start Date Order End Date Order Quantity
A 07-Feb 07-Feb 100
A 10-Feb 10-Feb 100
A 15-Feb 15-Feb 100

Remember that the lead times for A, B, and C are 2 days each, and that the usage quantities for B and C are 2 and 3 respectively. 05-FEB and 06-FEB are non workdays.

Required Dates and Required Rates for B and C
Item Rate Start Date Rate End Date Daily Rate
B 01-Feb 01-Feb 200
C 01-Feb 01-Feb 300
B 04-Feb 04-Feb 200
C 04-Feb 04-Feb 300
B 09-Feb 09-Feb 200
C 09-Feb 09-Feb 300

The following table illustrates how the repetitive schedule allocation process would divide the two repetitive schedules across Lines 1 and 2 using the line priorities and production rates specified earlier.

Repetitive Schedule Allocation
Item Line Required Rate Max Hourly Rate Production Rate Load Factor Load Rate
B Line 1 200 100 75 1.33 267
C Line 1 300 100 100 1 300

Required Rate

Required rate represents the production rate allocated to an individual production line by the repetitive schedule allocation process. In this example, there is sufficient capacity to allocate the entire required rate for B to Line 1 since Line 1 has a production rate of 75/hour for B, and is available for 12 hours/day. Similarly, there is sufficient capacity to allocate the entire required rate for C to Line 2.

Load Factor

Rate-based CRP uses load factors to aggregate required rates across a line since different items often require different production rates on the same line. Aggregating load rates rather than required rates ensures that line requirements generated by different items are aggregated on an equal basis. Rate-based CRP calculates load factors using the following formula:

load factor = max hourly rate / production rate



In this example, the maximum hourly rate for Line 1 is 100/hour, and the production rate for item B on Line 1 is 75/hour. Rate-based CRP would calculate the load factor for item B on Line 1 as 100/75 = 1.33.

Load Rate

Load rate represents the weighted required rate for a production line. Rate-based CRP calculates load rates using the following formula:

load rate = required rate x load factor

In this example, the required rate for item B on Line 1 is 200/hour, and the load factor for item B on Line 1 is 1.3. Rate-based CRP would calculate the load rate as 200 x 1.33 = 267 units per hour.

The previous table illustrates the required rate for each item/line combination for one day. Rate-based CRP aggregates the load rates by line and stores them as a required rate for the line for each day within the period defined by the rate start and end dates.

The following table illustrates the required rates and dates for Line 1.

Required Dates and Required Rates for Line 1
Line Required Date Required Rate
Line 1 01-Feb 567
Line 1 04-Feb 567
Line 1 09-Feb 567

The following table illustrates how rate-based CRP uses required dates to bucket the required rates for Line 1 into weekly buckets. The example assumes that the first bucket starts on 31-JAN.

Bucketed Required Dates and Required Rates for Line 1
Week Start Date Line Required Rate
31-Jan Line 1 1134
07-Feb Line 1 567

Available Rate Calculation

Like rate-based RCCP, rate-based CRP calculates the available rate for a production line using the line availability information you define in Oracle Work in Process and Oracle Bills of Material.

Rate-based CRP calculates the available rate for a production line using the following formula:

available rate = max hourly rate x line hours per day x line days per week

Line hours per day represents the start and stop times you specify for the production line in Oracle Work in Process. Line days per week reflect the number of workdays in the week based on the workday calendar you define in Oracle Bills of Material.

The following table illustrates how rate-based CRP would calculate the available rate for Line 1 assuming that you have defined it to be available 12 hours per day, 5 days per week. In this example, rate-based CRP would calculate the available rate for Line 1, for the week starting 31-JAN, as 100 x 12 x 5 = 6,000 units per week.

Available Rate for Lines 1
Line Max Hourly Rate Line Hours/Day Line Hours/Week Available Rate
Line 1 100 12 5 6,000

Load Ratio Calculation

Rate-based CRP calculates capacity load ratio for each line by dividing the total required rate per week by the total available rate per week, using the following formula:

capacity load ratio = required rate / available rate

The following table illustrates how rate-based CRP would calculate capacity load ratio for Line 1 for the weeks starting 31-JAN and 07-FEB. In the Resource Requirements Snapshot Example, the capacity load ratio of Line 1 for the week starting 07-FEB is 1134/6000 x 100% = 18.9%.

Capacity Load Ratio
Week Start Date Required Date Available Rate Capacity Load Ratio
31-Jan 1134 6000 18.9%
07-Feb 567 6000 9.4%

Notice that the rough cut analysis reveals that Line 1 is underloaded in both weeks.

Generating CRP

You can generate your routing–based and rate–based CRP plans, on–line, for any material requirements plan you choose. You can specify a simulation set, and a resource group when generating your CRP plan, and you can optionally choose to aggregate requirements for multi–department resources across all the departments that share them.

See Also:

Viewing CRP

You can use the Planner Workbench in Oracle Master Scheduling/MRP and Oracle Supply Chain Planning to view capacity information. You can display the weekly capacity requirements for a material requirements plan. You can compare capacity requirements to available capacity and review weekly capacity load ratio. You can display capacity plans for individual resources, in hours per resource per week, or for production lines, by production rates per week per line.

See Also

Viewing Capaicty Information from the Planner Workbench, Oracle Master Scheduling/MRP and Oracle Supply Chain Planning User's Guide

To view capacity information:

  1. Navigate to the Planner Workbench.

  2. Find the plan for which you want to find capacity information.

  3. Choose Resources.

    The Find window appears.

  4. Enter your search criteria in any of the following fields:

    • Org

    • Department Class

    • Department/Line

    • Maximum Rate

    • Minimum Rate

    • Owning Department

    • Resource

    • Resource Type

  5. Select a Condition.

  6. Enter a value for From and, if necessary, one for To.

  7. Choose Find to find capacity information that matches the search criteria you just entered.

    The Resource window appears.

    Note: You can query in Load Ratio to see for which dates a department/resource is overloaded/underloaded. For example, specify ”>100” in the query to see which weeks this department/resource is overloaded. See: Performing Query–by–Example and Query Count, Oracle Applications User’s Guide

    To generate a graphical display of capacity data

    You can view a graph of the horizontal capacity data. The graph contains:

    • all horizontal plan data

    • a graph comparing load to capacity

    • optionally, a pivot table

    1. Navigate to the Resource window.

    2. Check the Resources.

    3. Choose Horizontal Capacity Plan.

    4. Choose Graph.

Resource Requirements Snapshot

The first step in calculating detailed capacity requirements, for both routing and rate-based CRP, is to load resource requirements from Oracle Bills of Material and Oracle Work in Process. This is done by the Snapshot during the planning process.

The capacity requirements calculated for each resource by routing-based CRP represent the summation of the requirements generated by planned orders, suggested repetitive schedules, discrete jobs, and non-standard jobs. The Snapshot loads resource requirements for planned orders and suggested repetitive schedules from Oracle Bills of Material and loads resource requirements for discrete and non-standard jobs from Oracle Work in Process.

The resource requirements loaded from Oracle Bills of Material are also used by rate-based CRP when calculating rate requirements on production lines. Resource requirements are based on the effective date ranges in routings. Resource requirements for phantom assemblies are included in the requirements for the planned orders of their parent assemblies.

Resource Requirements Snapshot Example

The following examples illustrate the resource requirements load by the Snapshot for two components, B and C, and their parent item, A. The following table illustrates the bill of material for A.

Bill of Material for A
Level Item Quantity
1 A 1
.2 .B 2
.2 .C 3

The following table illustrates the corresponding routings and associated resource usages for items A, B, and C.

Routings for A, B, and C
Item OpSeq Dept Resource Basis UOM Usage
A 10 D3 R1 Item HR 4
A 20 D3 R2 Item HR 4
B 10 D2 R1 Item HR 6
B 20 D2 R2 Item HR 6
C 10 D1 R1 Lot HR 8
C 20 D1 R2 Item HR 8

Usage Rate

Usage rate represents the amount of resource required to build one unit of an item at a particular operation. The usage rate is stated the unit of measure you specify when defining the resource in Oracle Bills of Material. In the Resource Requirements Snapshot Example, building one unit of C at operation 20 requires 8 hours of D1, R2.

Note: Oracle Capacity only plans routing-based capacity for resources that have a unit of measure that is time-based and can be converted to hours.

See Also: Basis

Resource Requirements from Oracle Bills of Material

The following table illustrates the resource requirements loaded by the Snapshot from Oracle Bills of Material. These are used by routing-based CRP to calculate resource requirements for planned orders and repetitive schedules.

Table: Resource Requirements for A, B, and C

Runtime Quantity

Runtime quantity represents the number of resource hours required per resource unit to build one unit of an item at an operation. Runtime quantity is derived from the usage rate and unit of measure you specify in Oracle Bills of Material. If you have defined a usage rate using a unit of measure other than hours, the Snapshot converts it to an hourly rate.

Runtime quantity is analogous to the required hours generated by the bill of resource load process in RCCP. In Resource Requirements Snapshot Example, building one unit of A at operation 20 requires 8 hours per unit of D1, R2.

Basis

Basis is used to specify whether a resource is required on a per item or per lot basis. Basis has a direct impact on the hours required of a resource at an operation.

If the resource basis is Item, increasing the number of items to be processed at an operation increases required hours. For example, doubling the number of items that require grinding doubles the hours required of a grinder. The relationship between required hours, runtime quantity, and order quantity for Item basis resources is represented by the following formula. In the example, all resources except D1, R1 are item basis resources.

If the resource basis is Lot, increasing the number of items to be processed at an operation does not have an effect on required hours. For example, doubling the number of items that require drying does not double the hours required of a drying room. The relationship between required hours and runtime quantity for Lot basis resources is represented by the following formula. In the Resource Requirements Snapshot Example, D1, R1 is a lot basis resource.

Resource Offset

Routing-based CRP applies resource offsets to lead times to determine the time period before the completion of an item that a resource is required. This time period, which is analogous to the setback days calculated by the bill of resource load for RCCP, is calculated using the following formula:

Routing-based CRP then calculates resource requirement dates by applying the resource offset to order due dates using the following formula:

Order date represents the planned order due date for planned orders and the completion date for discrete and non-standard jobs. Routing-based CRP treats suggested repetitive schedules as if they were planned orders for each workday between the schedule start date and the schedule end date, so for repetitive schedules, order date represents any date for which the schedule is active.

In RCCP, setback days for bills of resources is derived from processing lead times that are calculated by the lead time rollup process using the lead time lot size for the item. This is necessary since RCCP cannot anticipate what actual demand quantities will be placed via a master schedule. Since CRP uses actual planned order, repetitive schedule, and work in process job quantities, it can use the more accurate lead times calculated by the planning process using the following formula:

As a result of these more accurate lead times, CRP calculates resource requirement dates that are more realistic than those calculated by RCCP.

Resource Requirements from Oracle Work in Process

The following table illustrates the resource requirements loaded by the Snapshot from Oracle Work in Process. These are used by routing-based CRP to calculate resource requirements for discrete and non-standard jobs. The example assumes that you have defined a discrete job for 6 units of A, due to complete on 07-FEB. 05-FEB and 06-FEB are non workdays.

Resource Requirements from a Discrete Job for A
Item Op Seq Dept Res Operation Hours Required Operation Hours Expended Operation Start Date
A 10 D3 R1 24 0 03-Feb
A 20 D3 R2 24 0 04-Feb

Operation Hours Required

Operation hours required represents the number of hours required to complete the total job quantity scheduled for an item at an operation.

Operation Hours Expended

Operation hours expended represents the number of hours that have been consumed by partial completion of the total job quantity at an operation.

If a job has not yet started consuming resources at an operation, then expended hours is zero. In this example, no resources have been consumed so far by the discrete job for A.

Operation Start Date

The operation start date represents the date when a resource is expected to be consumed. Oracle Capacity assumes that all resources for an operation are consumed at the start date of the operation.