Rough-cut capacity planning (RCCP) uses representative load profiles to evaluate key resources like work centers and ensure the feasibility of the master production schedule before detailed planning. It identifies potential capacity issues and initiates actions to adjust capacity. The resource profile technique converts the MPS to resource time requirements using standard times and lead time offsets. A master schedule is considered realistic if required capacity is no more than 10-20% above planned capacity based on utilization and efficiency factors. RCCP is an important part of production planning and control systems to develop achievable schedules and balance requirements with factory output.
2. Capacity
Planning (RCCP)
Type of capacity planning using some
load profiles (sometimes called
“representative routings) defined for
the product families, focused on key
or critical work centers, lines,
departments, cells, suppliers, and
support areas (engineering,
distribution, shipping).
3. Importance of RCCP
MRP system assumes that needed capacity always
is available.
RCCP helps to identify the key resources and to
test the feasibility of the supply plan, production
plan and master schedule before doing any
detailed capacity/material planning.
It also helps to initiate action for making mid- to
long-term capacity adjustments.
4. What is RCCP and
how does it work?
Rough Cut Capacity Planning (RCCP) is a rough check
to evaluate all the key resources, to test the validity of
MPS, to determine the feasibility of fulfilling the
approved Production Plan that was developed in the
Sales & Operations Planning process.
Once the master scheduler determines that a realistic
plan exists, the production plan is then load into MRP to
drive the allocation for all the lower-level materials. The
production plan now translates into discrete part
numbers, quantities and due dates.
5. Overstated MPS
It is a problem commonly
encountered in operating MRP
systems .
An overstated master production
schedule is one that orders more
production to be released than
production can complete.
6. Causes of Overstated MPS
It causes raw materials and WIP
inventories to increase.
It also causes a build-up of job queues
on the shop floor.
Since jobs have to wait to be processed,
actual lead time increase.
As lead times increase, forecast
accuracy over the lead-time diminishes.
7. Few reasons of why RCCP
techniques are not used in
some companies are:
Data requirements are quite high - firm
demand, forecasts, past data, lead times,
utilization, products and process
knowledge.
They don't have a stable MPS.
They don't have the right skill, it is very
time-consuming, or they are doing it the
wrong ways.
8. Standard Time
It refers to Setup time and Run
time (processing time) which
impact the workload on a
resource because it actually tie
up that resource.
9. Lead-Time Offset
It is the time between the need
for the resource and the date that
the product has been promised.
Lead-Time Offset is necessary if a
product has longer lead times.
10. When using process routings sheet and
BOM to create the Resource Profile, it is
better to use this formula
Required Resource Time = (Run Time x BOM qty)
+ (Setup Time x number
of Setups required)
+ margin % of total
non- standard times
11. Several types of capacities
being used:
Demonstrated Capacity
- This is the proven or historical capacity
of a key resource or work center.
Demonstrated capacity could potentially
change if resources are added or if operations
are altered. In such case, adjustments to
planned capacity must be considered before
making evaluation of the production plan.
12. Planned Capacity
- This is demonstrated capacity plus or minus
anticipated changes or adjustments to the
product-flow process.
Maximum Capacity
- This is the maximum load a resource can
handle under any reasonable set of
circumstances. This can be achieved through
several means: use of available overtime, adding
shifts, staff additions, offload volume to outside
vendors, pay extra for supply priorities, paying
premium freights to expedite materials delivery,
etc).
13. Determining Capacity
Available or Planned
Capacity
Adjustment Factors:
Utilization. Utilization is a number between 0
and 1 which is equal to 1 minus the proportion of
time typically lost due to machine breakdown,
labor shortage, parts failure, or material
unavailability.
Efficiency. Efficiency is defined as the average of
standard hours of actual production (after minus
the unavoidable lost time - setup time, change
shift, rest time).
14. If a time standard is exactly right,
efficiency is 1.
If the time actually required to
perform the work is less than the
standard, efficiency is more than 1.
If the time actually required to
perform the work is more than the
standard time, efficiency is less
than 1.
15. Capacity available is determined
by multiplying time available x
utilization x efficiency
Capacity Available = Time Available
x Utilization
x Efficiency
16. The Resource Profile
Technique
This technique is designed to convert the master
production schedule from units of end items to
be produced into the amount of time required on
the key resources.
Resource Profile approach considers lead-time
offsets.
Resource Profile technique is the most detailed
rough-cut approach, but is not as detailed as
Capacity Requirements Planning.
Resource Profile technique uses detailed data on
the time standards for each product at the key
resources.
17. Time Standard
It is the time it should take an
average worker working at a normal
pace to produce one unit of an item.
The time standard for any part has
built into it an allowance for rest to
overcome fatigue or unavoidable
delays, etc.
18. It would seems logical to accept that if
the required capacity is :
No more than 10% greater than the
planned capacity, the master schedule is
considered realistic.
More than 20% greater than the planned
capacity, the master schedule is considered
unrealistic.
Between 10% and 20% greater than the
planned capacity, the master schedule is
questionable.
19. In many of today's ERP systems, there is
also a "What-If" scenarios analysis
capability being built into the capacity
planning module, that makes it possible
for the scheduler to juggle the numbers -
shifting workers, reschedule in and -out,
alternate routings, splitting lots, add
equipments, off-loading to vendors,
overtime, hiring temporary workers and
so on.
20. 3 Approaches to Rough-
Cut Capacity Planning
Capacity planning using Overall factors
(CPOF) Approach – the least detailed
approach which is quickly computed but is
insensitive to shifts in product mix.
Bill of Labor – a second approach which
involves multiplying two matrices, the bill of
labor and the master production schedule..
Resource Profile – approach which takes
lead-time offsets into account.
21. Drum-buffer Rope
It is an emerging procedure that
eliminates the need for iteration
found in all RCCP approaches.
It is presently used by a small but
growing number of corporations.
22. Material Requirements
Planning (MRP)
It uses Master Production Schedule
(MPS) of end items to determine the
quantity and timing of component part
production.
It is capacity insensitive; it implicitly
assumes that sufficient capacity is
available to produce components at the
time they’re needed.
23. APICS Monograph
(Berry, Voliman, and Whybark
1979) presents case histories of
several companies, including
details on the capacity
planning process.
24. Production Planning &
Control
Capacity management techniques usually
are separated into four categories that
represent the four time horizons :
Manufacturing Resource Planning (MRP
II)
Aggregate Production Planning
Rough Cut Capacity Planning (RCCP)
Capacity Requirements Planning (CRP).
25. In any MRP system, the same
sequence is to create a master
schedule, use Rough Cut Capacity
Planning to verify that the MPS is
feasible, perform the MRP
explosion, and send the Planned
Order Release data to Capacity
Requirements Planning
26. Role of RCCP in the overall PPC system:
To develop an achievable Master Production Schedule.
To plan and control priorities and capacities.
Priority Planning is the process of specifying batch
quantities and their start and finish dates for all Supply
Orders where procurement and manufacturing are involved.
Priority Control is making the right things at the right time.
It is completely dependent on maintaining a balance
between MPS requirements and factory Output rates, in
which suppliers delivery performance is vital.
Capacity planning is the task of determining how much
output is needed from factory and from suppliers.
Capacity control is the comparison between planned levels
and actual outputs achieved, and the identification of
significant variances above or below plan. Corrective action
must be done quickly (adjust capacity or changing the
master schedule).
27. Typical resources that might be planned as
pat of rough-cut capacity planning:
Overall plant capacity
Labor hours in total or for people with unique skills
Assembly hours in a specific cell or bottleneck
process.
Testing cell capacity
Engineering hours needed to configure the final
product to the customer’s specification.
Space required in a warehouse or storage area
Waste or effluent release, etc.
Shipping labor
Design time or credit release time
Inspection or QC time
Supplier Capacity
28. Rough-Cut Capacity
Planning Functions
Shows consumption of critical resources.
Enables master schedulers to:
Test end-item production plans
Calculate capacity to meet the master schedule
Compare and modify required and planned
capacity
Analyze load on key resources by time period
Isolate and resolve potential problems.
29.
30. Rough-cut Capacity
Planning V.S. Capacity
Planning
CRP uses time-phased material plan
information, while RCCP uses aggregate data.
MRP takes into account capacity stored as
inventory.
Shop floor systems take into account W.I.P. –
only consider what's needed to complete the
requirement.
CRP considers service and spare parts
requirements also.
31. EXAMPLE problem:
Let's assume a lamps manufacturer I call
it Johor's Lamps. Johor's Lamps runs 3
shifts, 120 hours per week from Monday
to Friday; Planned Production Lost Time
per shift (change shift & rest time) is 35
minutes, and company allows a
maximum overtime of 10% of per shift
either during weekdays or through Sat.
& Sunday.