Summary Production Planning and Control Revision Poster

ME20026: PRODUCTION PLANNING AND CONTROL:
MANUFACTURNG OPERATION PLANNING AND CONTROL: P:D RATIO:
 Concerned with managing the day-to-day activities of the
organisation to satisfy customer demands PRODUCTION
Definition MANAGEMENT STRATEGIES
 Planning
o The ratio of total throughput (P) to the time
o Formalised forecast of events that will happen in the future Push Strategies:
it takes for the product or service to be
 Variables that can cause things to happen differently to planned Production signals are generated in a top down manner based on demand forecasts
delivered to the customer after the order is
o Changes in customer decisions Signals then given to workstations which push processed parts to the subsequent workstation
placed (D).
o Suppliers not delivering on time Examples of push strategies
The lower the P:D ratio, the lower the uncertainty
o Machine breakdowns o Material requirements planning (MRP)
and risk in production planning and control
o Other unavailability of resources e.g. staff illnesses o Master production schedule (MPS)
 Control o Manufacturing resource planning (MRPII)
o Process of coping with changes in such variables o Enterprise resource planning (ERP)
o Allows objectives of plan to be met, even when assumptions
on which the plan was based are no longer applicable


SEQUENCING:
 Determining the order and time in which various jobs should be carried out with limited
resources
Sequencing rule Description  Methods for sequencing
Physical constraint Sometimes mix of work arriving at a partMaterial Requirements
of an operation may Planningo (MRP): Physical restraints
determine the priority given to jobs o Utilises bill of materials (BOM)
o Customer priority
(e.g. when fabric is cut to a required size and shape,  A surplus
listing of all raw materials, parts, subassemblies and
Production Management Strategies: o Due date (DD)
fabric is waste) assemblies needed to produce one unit of a product
 Concerned with deciding the manner in which signals are given o Last in first out (LIFO) Manufacturing Resource Planning (MRP
Jobs that physically fit together may be scheduled o Also utilisesto
together master production schedule (MPS) II):
to a production system for starting and stopping work o First in first out (FIFO)
reduce waste  Makes timing and volume calculations to meet forecast o Development of MRP
 Divided into push and pull strategies o Longest operation time (LOT)
Customer priority Allows important or aggrieved customer or item demand
to be o MRP and information systems
o Shortest operation time (SOT)
processed prior to others, irrespective of theiroorder BOMofisarrival
traversed from top to bottom
o Johnson’s algorithm related to it are integrated in a
Due date (DD) Work is sequenced according to when it is due for Allows orders for all parts of the product to be specified
delivery,  Methods aim to improve performance objectives of single framework
dependability, speed and cost
Enterprise Resource Planning (ERP):irrespective of the size of each job or the importanceo Items calculated
of each for each subassembly for each time period
Forward and backward scheduling used to develop othe timing
Singleof individual
database activities
is held for
o Extension of MRP II outside he
customercompany  Gross requirements
o Forward scheduling systems such as
Last in o
firstAllows resources withinUsually
out (LIFO) entire selected
enterprise to be managed
for practical purposes  The total quantity needed from the item in the time
 Tasks are completed as early as possible  Inventory management
within a single framework e.g. unloaded an elevator is more convenient on a LIFO basis, period  Capacity management
o Systems such as human resources,  Scheduled receipts  Offers
as there is only onefinance
entranceetc.and are
exit  Highdue labour utilisation  Production planning
First in firstintegrated
out (FIFO)with production
Akamanagement strategies
first come first served (FCFS)  Quantity that will be received to orders placed before
the planning period  Flexibility
Longestooperation
Advantage time (LOT) Sequence longest jobs first o Backward scheduling
 Enterprise’s ERP can communicate with the
Advantage: occupies ERPcentres
work for long periods Projected on hand inventory
in other
 Tasks are item
completed
enterprises  The amount of inventory of the that isasexpected
late as possible
to
Shortest operation time throughout
(SOT) the supply
Normally chain
when operations become cash constrained  period
Offers
 Introduces unprecedented levels of flexibility in the exist at the given time
Short jobs tackled first  Lower material costs
supply chain management  Planned receipts
Jobs can hence be invoiced and payment received to ease  beLess exposure to risks
 The quantity of items to received in the timeinperiod
case of
asorder changes
cash-flow problems
the result of orders
Goalsinofthe
sequencing
planning period
 Planned order releases o Minimise makespan
 Timeinfrom
 The quantity that is ordered the start
time of first job to finishing of last job
period
o Minimise lateness
 How far tasks go beyond their deadlines