Production Planning and Control Introduction • • • • Coordination of materials with suppliers Efficient utilization of people and machines Efficient flow of materials Communication with customers PPC Class Notes- Production Planning and Control Introduction A T y p i c a lM a n u f a c t u r i n g S y s t e m s S U P P L I E R S R a w M a t e r i a l s M a t e r i a l s M a c h i n e s P e o p l e C U S T O M E R S PPC Class Notes- F i n i s h e d P r o d u c t s Decision Making vs. Decision Support • Authors claim that PPC system does not make decisions or manage the operations • Managers perform these activities • PPC system provides support for decision making PPC Class Notes- Decision Making vs. Decision Support (Cont’d) • However, developing intelligent software is becoming increasingly feasible • Software not only to support decision makers but also make (at least) some of the decisions • Expert Systems, Neural Networks, Genetic Algorithms, Evolutionary Programming, Genetic Programming, Tabu Search, Simulated Annealing, etc. are available techniques PPC Class Notes- Activities Supported by PPC • Materials Planning • Purchasing • Raw Material Inventory Control • Capacity Planning • Scheduling Machine and People • WIP Inventory Control PPC Class Notes- Activities Supported by PPC (Cont’d) • Coordinate Customer Orders • Finished Goods Inventory Control PPC Class Notes- Costs and Benefits of PPC Systems PPC requires a large # of indirect people Companies with ineffective PPC system will have poor customer service, excessive inventories, low equipment and people utilization, high rate of part obsolescence, large number of expediters PPC Class Notes- Company Game Plan Overall direction for PPC is provided by a Company Game Plan Game Plan links various departments (engineering, finance, marketing, production) It should be consistent with strategic plans, budgets, and company’s capabilities PPC Class Notes- Hierarchical Planning 1. Overall Manufacturing Planning 2. Detailed Materials and Capacity Planning 3. Execution of Plans PPC Class Notes- Production Planning and Control General Framework Resources Planning Production Planning Demand Management Rough-cut Capacity Planning Master Production Scheduling Detailed Capacity Planning Detailed Material Planning Material and Capacity Plans Shop Floor Systems Purchasing PPC Class Notes- 1.Overall Manufacturing Planning Hierarchical Planning Cont’d Demand Management • Forecasting • Order Promising • Order Processing • Order Entry • Spare Parts PPC Class Notes- 1.Overall Manufacturing Planning Hierarchical Planning Cont’d Production Planning Monthly Plans for Product Families Master Production Scheduling (MPS) Weekly Plans for Individual Products MPS must sum up to Production Plan PPC Class Notes- PP – MPS Relation nk s M P S P ijk t =P k t k = 1 ,2 ,3 ,… ..,f;t= 1 ,2 ,3 ,… ..,T i= 1j= 1 s n u m b ero fsu b p erio d sinap erio d n n u m b ero fp ro d u ctsinfam ilyk k M P S m asterp ro d u ctio nsch ed u lefo rp ro d u ctiof ijk t fam ilykinsu b p erio djo fp erio dt P P p ro d u ctio np lanfo rfam ilykinp erio dt k t f n u m b ero ffam ilies T n u m b ero fp erio d s PPC Class Notes- Example Product Family: Markers Products: Red, Blue, Green Marker Note:Usually a period is one month and a subperiod is one week (s=4). PPC Class Notes- Example (Cont’d) ProductionPlan M onths 1 2 M arker Family 100000 120000 M aster ProductionSchedule Products W eeks 1 2 3 4 1 2 3 Red 10 10 10 10 15 15 15 Blue 10 10 10 10 10 10 10 Green 5 5 5 5 5 5 5 PPC Class Notes- 4 15 10 5 1.Overall Manufacturing Planning Hierarchical Planning Cont’d Resource Planning • Long-Range Capacity Requirements • Number of Machines • Number of Employees • Overtime • Shifts • Plants PPC Class Notes- 1.Overall Manufacturing Planning Hierarchical Planning Cont’d Rough-Cut Capacity Planning Capacity Requirements for Master Production Scheduling • Overall Factor • Capacity Bills • Resource Profiles PPC Class Notes- 2.Materials & Capacity Planning Hierarchical Planning Cont’d Materials Planning Production rates can be used in simpler manufacturing systems. Materials Requirements Planning (MRP) can be used in more complex systems. MRP determines time-phased requirements (period-by-period) for all purchased and manufactured parts such as raw materials, components, parts, subassemblies, etc. PPC Class Notes- 2.Materials & Capacity Planning Hierarchical Planning Cont’d Detailed Capacity Planning Labor Hours Required Machine Capacity Required In an MRP environment, this task is accomplished by using the Capacity Requirements Planning (CRP) technique. PPC Class Notes- 3. Execution of Plans Hierarchical Planning Cont’d Shop Floor Control • Conventional Approach, Process Layout Similar machines are grouped into workcenters Use workorders to schedule the jobs through workcenters / departments Schedule machine and other workcenters Determine start and completion times of orders Update the schedule PPC Class Notes- 3. Execution of Plans Hierarchical Planning Cont’d Shop Floor Control (Cont’d) • Recent Trend, Manufacturing Cells Similar parts are grouped into families Corresponding machine cells are formed Use production rates Use schedules to control production (Family Sequencing, Product Sequencing, Cell Loading, Cell Scheduling, etc.) Use Kanban System (Pull, Just-in-Time) to control production PPC Class Notes- 3. Execution of Plans Hierarchical Planning Cont’d Purchasing • Purchasing Plan • Vendor Search • Quotation • Order Release • Order Follow-up • Vendor Capacity PPC Class Notes- Planning vs. Control • Plans are made • Results are compared with plans (control) • Results are OK Wait until next control period • Results are not OK Go to Step 1 (Revise plans) PPC Class Notes- An Example Resource Planning: Assume that a jewelry manufacturing company decided to open three manufacturing sites (US, Ireland and Singapore). Each plant is going to run one shift except plating area which will be run 2 shifts due to high investment requirement. PPC Class Notes- Example Cont’d D em a n dM a n a g em en t: D em an disfo recastedfo rd ifferen tp ro d u ctfam iliesan d d ifferen tp lan tsasfo llo w s: U Sp lan t Irelan dp lan t S in g ap o re p lan t E arrin g s 3 0 0 0 0 0 u n its/y r2 0 0 0 0 0 u n its/y r1 5 0 0 0 0 u n its/y r P en d an ts 3 5 0 0 0 0 2 2 5 0 0 0 2 0 0 0 0 0 R in g s 1 5 0 0 0 0 1 0 0 0 0 0 7 5 0 0 0 PPC Class Notes- Example Cont’d P ro d u ctio nP la n s: U SP lan t M o n th s 1 2 3 4 5 6 7 8 9 1 01 11 2 E arrin g2 0 K2 0 K2 0 K2 0 K2 0 K2 0 K3 0 K3 0 K3 0 K3 0 K3 0 K3 0 K P en d an t 2 0 K2 0 K2 0 K2 0 K2 0 K2 0 K3 0 K4 0 K4 0 K4 0 K4 0 K4 0 K R in g 1 0 K1 0 K1 0 K1 0 K1 0 K1 0 K1 5 K1 5 K1 5 K1 5 K1 5 K1 5 K P R O D U C T IO N P L A N ISP R E P A R E D F O RIR E L A N D A N D S IN G A P O R EP L A N T SA SW E L L . PPC Class Notes- Example Cont’d DemandManagement: Followingmanpower andresources requirements areestimatedfor eachplant: Manpower Machine TypeX Machine TypeY Machine TypeZ USplant Irelandplant 300 200 Singapore plant 150 50 40 30 100 120 50 150 40 70 PPC Class Notes- Example Cont’d Master ProductionSchedule: USPlant –EarringFamily –1ST Month 1 GoldEarring GoldEarringwithred stone Silver Earring Silver Earringwithred stone TOTAL Weeks 2 3 4 1K 1K 1K 2K 1K 1K 2K 1K 1K 2K 1K 1K 2K 1K 1K 1K 5K 5K 5K 5K MASTERSCHEDULEISPREPAREDFOREACHMONTH (POSSIBLYFORTHE1ST COUPLEOFMONTHS, NOTFOR THEENTIREYEAR) ANDPRODUCTFAMILY. PPC Class Notes- Example Cont’d Rough-cutC apacityPlanning: M anpow erandm achinerequirem entsarerevised. M anpow er M achine TypeX M achine TypeY M achine TypeZ U Splant 330 55 95 190 PPC Class Notes- Example Cont’d M aterialsPlanning: D etailedm aterial plansarepreparedforsubassem bliesand partstobem anufactured; com ponentsandrawm aterialsto bepurchased. 1 2 3 G old Silver Red Stone Plated parts 4 W eeks 5 6 7 8 9 10 11 12 3kg 3kg 2.5kg 2.5kg … 5kg 5kg 4kg 4kg … 3K 2K 3K 2K … 5K 5K 5K 5K … PPC Class Notes- Example Cont’d C apacityR equirem entsP lanning : W eeks 1 2 3 4 M anpow er 320 310 330 322 M achine 52 55 60 57 X M achine 90 92 98 95 Y M achine 178 163 172 170 Z 5 6 7 8 9 10 11 12 … … … … PPC Class Notes- Example Cont’d Purchasing: Contact vendors, evaluatequotesandcut purchaseorders. ShopFloorControl: Assignpartstobeplatedtodifferent platinglines Loadmanufacturingcellswithproductsanddeterminestart andcompletiontimes Cell1 Job1 Job3 Job7 Cell2 Job2 Job4 Cell3 Job5 Job8 Job6 0 5hr 7 10 22 25 3438 PPC Class Notes- Planning vs. Control p lan n in g P lan s n o co n tro l O K ? R ev ise y es S to p PPC Class Notes- Matching PPC with the Needs of the Firm Number of Subparts Just-in-Time MRP CPM/PERT Repetitive Flow Seconds Minutes Days Weeks Months Time between successive units Examples: Oil, food, drugs, watches, TV, trucks, planes, houses, ships PPC Class Notes- Matching PPC with the Needs of the Firm 1. Flow-Oriented Manufacturing Systems Very short time between successive units A few components needed Flow rate is the measure Ex: Chemical, food, petroleum PPC Class Notes- Matching PPC with the Needs of the Firm (Cont’d) 2. Repetitive-Nature Manufacturing Systems Short time between successive units Assemble similar products Flow Rate or Assembly Rate is the measure Ex: Televisions, Radios, Watches, Cars PPC Class Notes- Matching PPC with the Needs of the Firm (Cont’d) 3. Just-in-Time High production volume Low Product Variety Reduced Inventory and Leadtime Ex: Cars, Computers, Jewelry, Copy Machines PPC Class Notes- Matching PPC with the Needs of the Firm (Cont’d) 4. Materials Requirements Planning (MRP) Batch production High product variety Low production quantity Ex: Electric Motors, Fans PPC Class Notes- Matching PPC with the Needs of the Firm (Cont’d) 5. CPM/PERT Long leadtimes Low production quantity Ex: Airplanes, ships PPC Class Notes- Forces for Change Typical Responses Marketplace dictates Technology Products Processes Systems Techniques Shorter Product Life Cycles Time Based Competition Quality Requirements Company strategy Manufacturing Strategy Flexibility/Responsiveness Reduced Overhead costs Simplification Automation Production Cells Manufacturing processes MPC system PPC Class Notes- MRP JIT