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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.

Item Line Line Priority Line Speed 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
Table 1 - 24. Production Line Details for B and C (Page 1 of 1)

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.

Line Speed

Line speed represents the maximum hourly rate that you can build an assembly on a particular line. The line speed 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 line speed for a production line across all assemblies.

Rate-based CRP:

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.

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
Table 1 - 25. Master Schedule for A (Page 1 of 1)

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.

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
Table 1 - 26. Required Dates and Required Rates for B and C (Page 2 of 2)

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 line speeds specified earlier.

Item Line Required Rate Max Hourly Rate Line Speed Load Factor Load Rate
B Line 1 200 100 75 1.33 267
C Line 1 300 100 100 1 300
Table 1 - 27. Repetitive Schedule Allocation (Page 1 of 1)

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 line speed 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 line speeds 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:


In this example, the maximum hourly rate for Line 1 is 100/hour, and the line speed 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:


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.

Line Required Date Required Rate
Line 1 01-FEB 567
Line 1 04-FEB 567
Line 1 09-FEB 567
Table 1 - 28. Required Dates and Required Rates for Line 1 (Page 1 of 1)

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.

Week Start Date Line Required Rate
31-JAN Line 1 1134
07-FEB Line 1 567
Table 1 - 29. Bucketed Required Dates and Required Rates for Line 1 (Page 1 of 1)

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:


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.

Line Max Hourly Rate Line Hours/Day Line Days/Week Available Rate
Line 1 100 12 5 6,000
Table 1 - 30. Available Rate for Lines 1 (Page 1 of 1)

Utilization Calculation

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


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

Week Start Date Required Rate Available Rate Capacity Utilization
31-JAN 1134 6000 18.9%
07-FEB 567 6000 9.4%
Table 1 - 31. Capacity Utilization (Page 1 of 1)

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

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