Capacity Planning and Management Flashcards
Capacity Planning and Management
Consists of Three Parts
Resource Planning
Rough-Cut Capacity Planning (RCCP)
Detailed Capacity Planning (CRP)
Capacity planning and management addresses two managerial problems:
Match capacity to plans–by either providing sufficient capacity to execute plans or adjusting plans to meet available capacity.
Make capacity decisions considering customer service and capacity utilization.
Capacity Planning in the MPC System
3 Ranges
Long Range
- Resource Planning
- RCCP
Medium Range
1. CRP
Short Range
- Finite Scheduling
- Input/OutPut Control
Links to MPC Modules
5 Parts
- RP
Linked to strategic planning and sales and operations planning (SOP)
Plant and equipment investments, workforce level, etc.
- RCCP
Linked to master production schedule (MPS)
Converting MPS into requirements for key resources - CRP
Linked to material requirements planning (MRP)
Calculating time-phased capacity requirements to execute material plans generated by MRP - Finite Scheduling
Linked to material requirements planning and shop floor control
Detailed production scheduling within exact capacity constraints - Input/Output Control
Linked to shop floor control
Monitoring actual consumption of capacity during the execution of detailed production plans
The primary objective of RCCP and CRP techniques
is to estimate capacity requirements
Rough-cut capacity planning (RCCP)
Defined As
Capacity planning using overall factors (CPOF)
Capacity bills
Resource profiles
Capacity Planning Using Overall Factors (CPOF)
Simplest RCCP technique
Based on planning factors from historical data
Standard total production hours per unit of each product
Overall historical % workloads on work centers
Total capacity requirements are estimated from MPS and standard total production hours per unit of each product
The estimate is allocated to work centers based on overall historical workloads (rather than workloads on work centers of individual products)
Capacity Bills
Defined As
A bill of capacity is developed for each end product from its BOM and routing data
The bill of capacity indicates total standard time required to produce one unit of an end product by work center
The capacity requirements for each work center is estimated from the bills of capacity and the MPS data
Requires more data than CPOF
Resource Profiles
Rough-cut capacity planning technique that considers production leadtime information
Using operations setback charts
Provides time-phased projections of capacity requirements for individual work centers
CPOF (Capacity Planning Using Overall Factors) is simplest, but valid to use only when
when workloads on work centers are similar for all products or product mixes are relatively stable
Capacity bills provides more-direct linkage between
individual products and the capacity required for individual work centers
Resource profiles consider production
leadtime information, while CPOF and capacity bills do not
Capacity requirements planning (CRP) differs from
the rough-cut capacity planning procedures
CRP
4 Parts
Utilizes time-phased material plans from MRP
Takes into account components in stock
Accounts for the current status of work-in-process
Takes into account demand for service parts and other demands not accounted for in the MPS
MRP and CRP procedures
MRP generates material plans without considering capacity limits (infinite loading)
CRP calculates capacity requirements to examine the capacity implications of those plans
Assumes that if one knows of capacity requirements well in advance, either capacity or plan can be adjusted
Advanced planning and scheduling (APS)
Plan materials and capacity simultaneously
Better capacity utilization, faster total production leadtime, lower work-in-process inventories
* APS may also stand for Advanced Production Scheduling
Finite scheduling
(or finite loading) is not only a shop scheduling process but also an important part of advanced planning and scheduling
In finite scheduling, work centers are scheduled only up to their capacity limits
Establishes detailed schedules (start and finish times) of each job for each work center
When a work center’s capacity is not sufficient for all planned jobs, prioritization rules determine which jobs will be shifted to later times
Vertical loading
Scheduling a work center–independently
Horizontal loading
All work centers required to complete a job are taken into account
The highest-priority job is scheduled in all of its work centers, then the job with the next highest priority, and so on
Horizontal loading can be extended to entire product structure (end products, sub-assemblies, and components)
Forward scheduling
(or front scheduling)
Starts with the current date scheduling into the future, where each job is completed as early as possible
Backward scheduling
(or back scheduling)
Scheduling jobs backward from their due dates
Capacity Monitoring with Input/Output Control
One key capacity management issue concerns the match between planning and execution
Capacity data in input/output analysis are usually expressed in hours
Actual input/output vs. planned input/output in each period for each work center
Differences between plan and actual must be addressed
Actual/planned input and output
Planned input = Expected arrivals of jobs, expressed in standard hours
Actual input = Actual arrivals of jobs, expressed in standard hours
Planned output = Planned production hours
Results from staffing level, hours of work, etc.
Actual output = Actual quantities completed, expressed in standard hours
“Expressed in standard hours” means quantities multiplied by standard hour per unit
Actual Input vs. Planned Input
If actual input consistently larger or smaller than planned input, forecasting should be revisited.
Actual Output vs. Planned Output
If actual output is consistently larger or smaller than planned output, standard time should be updated.
Actual Input vs. Acutal Output
If actual input is consonantly larger or smaller than actual output, capacity should be charged.
