Tech 147: Analysis and Management of Production Systems

Unit 1

The Nature and Role of Production Planning, Design and Control in Manufacturing Systems

Objectives:

a) Describe the importance of production planning, design and control in manufacturing industry

b) Explore the applications of production planning, design and control in manufacturing industry

c) Define technical vocabulary employed in production planning, design and control

d) Investigate system analysis aspect of production planning, design and control in manufacturing industry

Technical Terms:

MRP MRPII

MPC Resource Planning

Master Production Scheduling MPS

Bill of Material ERP

Capacity Planning Lead Time

Time-phased Requirement Front End

Engine Back End

Production Systems Simulation Systems

Shop-Floor Systems Vendor Systems

Introduction:

Effectively using constrained resources is the task of production control activity in

a manufacturing organization

A Manufacturing System Consists of:

Equipment and facilities component: machines, tooling, equipment and facilities
Production methods and processes component: procedures, production methods, quality assurance, and production control
Materials and material moving and handling component: materials and material/tooling handling or moving systems
Labor component: people or men
End products

Vollman et al Chapter 1: Manufacturing Planning & Control:

MPC system is concerned with planning and controlling all aspects of manufacturing, including managing materials, scheduling machines and people, and coordinating suppliers and customers

The Context for MPC:

Internationalization
The role of the customer
Increasing use of information technology

Typical MPC Support Tasks:

· Plan capacity requirement for market needs

· Plan for materials to arrive on time

· Ensure proper utilization of equipment

· Schedule production activities

· Track materials, people, customers’ orders...

· Communicate with customers and suppliers

· Provide information to other functions etc.

Costs and Benefits of MPC Systems:

Substantial initial cost
Substantial payoffs in overhead, inventory, lead time and cycle time reduction etc.
Improved labor and machine productivity
Increased facility and equipment utilization

MPC System Framework:

· Front end

· Engine

· Back end

· See Figure 1.1 on page 8

Front End:

· Establishes company objectives for manufacturing planning and control

· Demand management encompasses forecasting customer or product demand

· Resource planning provides the capacity necessary to produce the required product

· Results in master production schedule

Engine:

· Set of systems for accomplishing detailed material and capacity planning

· MRP determines period-by-period plans for all component parts and raw materials required to produce all the products in MPS

Back end:

· Depicts the execution systems

· Single and multiple work centers

· Production cells of FMS

· Just-in-time

· Group technology

Evolution of the MPC System:

· New technology, products, processes, systems, and techniques permit new initiatives

· Global competition intensifies these forces

· Cost and quality are the ante to play the game

· Winning requires flexibility and responsiveness to customer demands

Vollman et al Chapter 5: Production Activity Control

· A PAC system is concerned with the planning and release of individual orders to both factory and outside vendors

· A PAC system can reduce work-in-process inventories and lead times as well as improve vendor performance

· PAC concerns execution of material plans. See figure11.1 on page 371

· Capacity plan is critical to managing detailed shop-floor flow of materials

· Material plan provides information to SFC and vendor follow-up systems

· Objective of SFC and vendor follow-up systems is to provide right part at right time

Linkages Between MRP & PAC

· Shop floor and vendor scheduling activities begin when an order is released

· MRP appraises the SFC systems of all changes in material plan

· Using its feedback capability, revised due dates and quantities for scheduled receipts are maintained

The Company Environment

· The primary PAC objective is managing materials flow to meet MPC plans

· Choice of objectives for PAC reflects company’s position to its competitors, customers, and vendors

· PAC systems are designed to meet particular firm’s needs

Basic Shop-Floor Control Concepts:

· Lead times =

o Run time +

o Setup time +

o Move time +

o Queue time

o (See page 375)

· Queue Time:

o Means time spent waiting to be processed at a work center

o Is the critical element

o Accounts for 80% or more of total lead time

o The element most capable of being managed

o Reducing queue time means shorter lead time and, therefore, reduced work-in-process inventory