2. MRP II -- Manufacturing
Resource Planning
• “A method for the effective planning of all
resources of a manufacturing company”
– Financial accounting incorporated
– Sales
– Operations Planning
– Simulate capacity requirements of different possible
Master Production Schedules
5. Long-Range Planning
• At the top of the hierarchy we have long-range
planning.
• This involves three functions: resource planning,
aggregate planning, and forecasting.
• The length of time horizon for long-range
planning ranges is around six months to five
years.
• The frequency for replanning varies from once
per month, to once per year, with two to four
times per year being typical.
• The degree of detail is typically at the part family
level.
6. Forecasting
• The forecasting function seeks to predict
demands in the future.
• Long-range fore-casting is important to
determining the capacity, tooling, and
personnel requirements.
• Short-term forecasting converts a long-
range forecast of part families to short-
term fore-casts of individual end items.
• Both kinds of forecasts are input to-the
intermediate-level function of demand
management.
7. Resource planning
• Resource planning is process of determining
capacity requirements over the long term.
• Decisions such as whether to build a new plant
or to expand an existing one are part of the
capacity planning function. .
• This information is fed as a parameter to the
aggregate planning function.
8. Aggregate planning
• Aggregate planning is used to determine levels
of production, staffing, inventory, overtime, and
so on over the long term.
• The level of detail is typically by month and for
part families. For instance, the aggregate
planning function will determine whether we
build up inventories in anticipation of increased
demand (from the forecasting function), "chase"
the demand by varying capacity using overtime,
or do some combination of both.
• Optimization techniques such as linear
programming are often used to assist the
aggregate planning process.
9.
10. Intermediate Planning
Included production planning functions:
• demand management
• rough-cut capacity planning
• master production scheduling
• material requirements planning
• capacity requirements planning
11. Demand management
• The process of converting the long-term
aggregate forecast to a detailed forecast
while tracking individual customer orders
is the function of demand management.
• The output of the demand management
module is a set of actual customer orders
plus a forecast of anticipated orders.
• As time progresses, the anticipated orders
should be "consumed" by actual orders.
12. Master production scheduling
• Master production scheduling takes the
demand forecast along with the firm orders from
the demand management module.
• Master production schedule contains an order
quantity in each time bucket for every item with
independent demand, for every planning date.
13. RCCP
• Rough-cut capacity planning (RCCP) is used
to provide a quick capacity check of a few critical
resources to ensure the feasibility of the master
production schedule.
• Although more detailed than aggregate
planning, RCCP is less detailed than capacity
requirements planning (CRP), which is another
tool for performing capacity checks after the
MRP processing.
• RCCP makes use of a bill of resources for each
end item on the MPS.
14.
15. CRP
• Capacity requirements planning (CRP)
provides a more detailed capacity check on
MRP-generated production plans than RCCP.
.
• In spite of its name, capacity requirements
planning does not generate finite capacity
analysis. Instead, CRP performs what is called
infinite forward loading.
16. Short-Term Control
• The plans generated in the long- and
intermediate-term planning functions are
implemented in the short-term control
modules, of job release, job dispatching,
and in-put/output control.
17. Job release
• Job release converts planned order
releases to scheduled receipts.
• One of the important functions of job
release is allocation.
• When there are several high-level items
that use the same lower-level part, a
conflict can arise when there is an
insufficient quantity on hand. By allocating
parts to one job or another, the job release
function can rationalize these conflicts.
18. Job Dispatching
The basic idea behind job dispatching is
simple: Develop a rule for arranging the
queue in front of each workstation that will
maintain due date integrity while keeping
machine utilization high and
manufacturing times low. Many rules have
been proposed for doing this.
19. Input/Output Control
• 1. Monitor the WIP level in each process center.
• 2. If the WIP goes above a certain level, then
the current release rate is too high, so reduce it.
• 3. If it goes below a specified lower level, then
the current release rate is too low, so increase it.
• 4. If it stays between these control levels, the
release rate is correct for the current conditions.
