production planning and control
TRANSCRIPT
ME 2402Production Planning & Control
Dr. S.RAVI
PROFESSOR
DEPT. OF MECHANICAL ENGINEERING
SRIRAM ENGINEERING COLLEGE
PPC Class Notes-Chapter1
Production Planning and ControlIntroduction
• Coordination of materials with suppliers
• Efficient utilization of people and machines
• Efficient flow of materials
• Communication with customers
PPC Class Notes-Chapter1
Production Planning and ControlIntroduction
A Typical Manufacturing Systems
SUPPLIERS CUSTOMERS Raw Materials Finished Products
Materials Machines
People
PPC Class Notes-Chapter1
Activities Supported by PPC
• Materials Planning
• Purchasing
• Raw Material Inventory Control
• Capacity Planning
• Scheduling Machine and People
• WIP Inventory Control
PPC Class Notes-Chapter1
Activities Supported by PPC(Cont’d)
• Coordinate Customer Orders
• Finished Goods Inventory Control
PPC Class Notes-Chapter1
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-Chapter1
Hierarchical Planning
1. Overall Manufacturing Planning
2. Detailed Materials and Capacity Planning
3. Execution of Plans
PPC Class Notes-Chapter1
Production Planning and ControlGeneral Framework
Production Planning
Master Production Scheduling
Detailed Material Planning
Material and Capacity Plans
Purchasing
Demand Management
Resources Planning
Rough-cut Capacity Planning
Detailed Capacity Planning
Shop Floor Systems
PPC Class Notes-Chapter1
1.Overall Manufacturing PlanningHierarchical Planning Cont’d
Demand Management
• Forecasting
• Order Promising
• Order Processing
• Order Entry
• Spare Parts
PPC Class Notes-Chapter1
1.Overall Manufacturing PlanningHierarchical 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-Chapter1
1.Overall Manufacturing PlanningHierarchical Planning Cont’d
Resource Planning
• Long-Range Capacity Requirements
• Number of Machines
• Number of Employees
• Overtime
• Shifts
• Plants
PPC Class Notes-Chapter1
1.Overall Manufacturing PlanningHierarchical Planning Cont’d
Rough-Cut Capacity Planning
Capacity Requirements for Master Production
Scheduling
• Overall Factor
• Capacity Bills
• Resource Profiles
PPC Class Notes-Chapter1
2.Materials & Capacity PlanningHierarchical 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-Chapter1
2.Materials & Capacity PlanningHierarchical 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-Chapter1
3. Execution of PlansHierarchical 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-Chapter1
3. Execution of PlansHierarchical Planning Cont’d
Shop Floor Control (Cont’d)• Recent Trend, Manufacturing Cells
Similar parts are grouped into familiesCorresponding machine cells are formedUse production ratesUse 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-Chapter1
3. Execution of PlansHierarchical Planning Cont’d
Purchasing
• Purchasing Plan
• Vendor Search
• Quotation
• Order Release
• Order Follow-up
• Vendor Capacity
PPC Class Notes-Chapter1
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-Chapter1
Planning vs. Control
planning no control yes
Plans
OK?
Stop
Revise
PPC Class Notes-Chapter1
Repetitive
Matching PPC with the Needs of the Firm
Flow
Number ofSubparts
Seconds Minutes Days Weeks Months
Time between successive units Examples: Oil, food, drugs, watches, TV, trucks, planes, houses, ships
Just-in-TimeMRP CPM/PERT
PPC Class Notes-Chapter1
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-Chapter1
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-Chapter1
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-Chapter1
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-Chapter1
Matching PPC with the Needs of the Firm (Cont’d)
5. CPM/PERT
Long leadtimes
Low production quantity
Ex: Airplanes, ships
PPC Class Notes-Chapter1
Forces for Change
TechnologyProductsProcessesSystems
Techniques
Marketplace dictates
Company strategy
Manufacturing Strategy
Manufacturing processes
MPC system
Shorter Product Life CyclesTime Based CompetitionQuality Requirements
Flexibility/ResponsivenessReduced Overhead costs
SimplificationAutomationProduction Cells
MRPJIT
Typical Responses