ie305 ch 2 production systems

7/28/2019 IE305 CH 2 Production Systems

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CHAPTER 2

Production Systems

IE 305 –

BUS 307

1



High

Profitability

Low

Costs

Low UnitCosts

High

Throughput

Less

Variability

High

Utilization

Low

Inventory

QualityProduct

High

Sales

Many

products

Fast

Response

More

Variability

High

Inventory

Low

Utilization

Short

Cycle Times

High Customer Service

Production Objectives

2



System Components and Hierarchy

3

Corporation

Parts Plant 2

Shaft Production

Gear Hobber

Power

Controller

Parts Plant 1 Assembly Plant 1

Robotic Load/

Unload

Tool

Exchanger

Force

Sensor

Equipment

level

Automated Part

Handling SystemCNC LatheCNC Mill

Gear ProductionHeat

TreatingPurchasing

Workstation

level

Department

level

Shop

level

Corporate

level

Parts Plant 2

Gear Hobber

Assembly Plant 1

CNC Lathe

Gear ProductionHeat

TreatingPurchasing



Production Activity

4

Fabrication

Plant

Assembly

Plant

Distribution

Center

Retailer

Forecasting

Strategic Planning

Aggregate Production

Planning

Disaggregation

Production Scheduling

Shop Floor Control

Administrative Functions

(Purchasing, Payroll,

Finance, Accounting)

Marketing

Product Design

Process Planning

Manufacturing Support

(Facilities Planning,

Tool Management,

Quality Control,

Maintenance)

a) Product Flow b) Decision Hierarchy c) Support Functions

Raw Material

Customer

Finished

Products



The Production System

• Definition:

– The set of resources and procedures involved in

converting raw material into products and delivering

them to customers

• Production and delivery of products are central to the

firm

– Functions have value only if they enhance the ability

to do this profitably

5



Decision Maker Compares / Benchmark actual information

with plan & generate the set of instructions for correcting thedeviations & sends it to control (Plan versus Actual)

Control sends instructions at an appropriate point for

execution & bring back process under control

Production System

CONVERSION

PROCESSINPUT OUTPUT

CONTROL

DECISION MAKER

6



The system selection is sensitive because of

the following parameters

1 . Type of Product

• Common parameters

• Total Volume

• Varieties in total Volume

2 .Type of Company

3.Life Cycle of Product / Project

7



8

Product Life Cycle



Life cycle phase of Project

Introduction ( Low volume

,High Variation)

Growth ( High volume , LowVariation)

Maturity ( High volume , Low

Variation)

Decline ( Volume drops ,

Variation High)

System selection is not a static or one time decision but

“DYNAMIC

”one & changes as organization passes throughI –G-M-D Phases & changes the equation of Volume to Variety

ratio

9



Types of Production System

CLASSIFICATION 1

Intermittent System Continuous System

Job Type Mass Production

Printing Job

Machine Building

Batch Type

Washing Machine

Fridge / TV / CAR

Spoons / Hair Pins /

Soaps / Chocolates

Process Type

Cement / Sugar /

Chemical Industries

10



•The goods are manufactured specially to fulfill orders made by

customers & not for stock

•Characteristics :

• Most products are produced in small quantities

•

Machines & equipments are laid out by process• Workloads are unbalanced

• Highly skilled operators are required for efficient use of machines

& equipments

•In process inventory is very large

• Flexible to accommodate variety in production

•Example : Machine shops, Hospitals, locomotives, Plants,

Automobiles

Intermittent System

11



OP1 Information & Control Decision Maker

OP3

OP2

OP4

Storage1

Storage 2

Storage 3

Storage 4

Storage 5

Ex. Paper cutting machine

Intermittent System

12



• Job Production : 1) It is the production of single complete unit by

one operator, Group of operators

2) Whole project is considered as one operation &

work is completed on each product before passing to the next

• Characteristics :• Complete project is considered as single operation

• Versatile & skilled labors are required

• High capital Investment

• Control operations relatively simple

•High unit cost of production

• Examples : Bridge Building, Dam Construction, Ship Building,

Heavy machines

Intermittent System Classification• Job Production • Batch Production

13



• Batch Production

•

Batch Production : It is a extension of job type productionWhole project is considered as one operation & work is completed on

each product before passing to the next

• Characteristics :

• Production schedule can be formulated according to

specific orders or demand forecasts

• Items are processed in lots & batches

• Only one item is produced in every production run

•

New batch will be taken only after completion of one• High WIP

• High cycle time

• Complex PPC

• Examples : Chemical Industry, Machine tools, Printing press,

Electronic instruments

Intermittent System Classification

14



Continuous System :

• In this system the items are produced for the stocks & not for specific order

• Manufacturing stock is based on sales forecast

•

Inputs are standardized & standard set of processes & sequence of processes can beused

OP1

Storage1

Information & Control Decision Maker Input

OP2

OP3 OP4

Storage2

OP5

Output

Ex. Bottling Plant

15



Types of Production Systems

CLASSIFICATION 2

There are four basic types of productionsystems:

1. Process

2. Product

3. Cellular

4. Fixed positions

16



Layout Goals

• Use space efficiently• Efficient personnel movement

• Maximum equipment utilization

• Convenient / safe work environment

• Simplify repair / maintenance

• Smooth flow of work

17



Products, Processes, and Layouts

Make-to-stock

standardized

commodities

Continuous

process industries

repetitive mfg

Product Layout

Assemble-to-order

modular

Hybrid, FMS,

CAM, CIMCellular Layout

Job-Shop(Intermittent) Process Layout

Engineer-to-order

one-of-kind

Special Project Fixed Position

PRODUCTS PROCESSES LAYOUTS

Make-to-order custom

low volume,

low variety

low volume,

high variety

low volume,

medium variety

high volume,

low variety

18



Fixed Position Layout

•The product or project remainsstationary, and workers, materials, and

equipment are moved as needed.

Examples: Home building, ship and

aircraft buiding, drilling for oil

19



Process Layout

Similar processes (or processes with similar needs)are located together

By grouping similar processes utilization of resources

is improved

Customers, products, patients move through theprocesses according to their needs

Different products = different needs = different routes

Complex flow pattern in the operation

Examples:

• Supermarkets, job-shops, hospitals

20



Process Layouts

Process Layout –products travel

to dedicated process centers

Milling

Assembly

& Test Grinding

Drilling Plating

21



Product Layout

Sometimes called line layout, flow line or assemblyline

Parts follow a specified route – the sequence of

workstations matches with the sequence of required

operations Work Flow is clear, predictable, easy to control

Examples:

• Car assembly, paper manufacture, self-service canteen

22



Product Layout

Raw

materials

or customer

Finishe

d itemStation

2

Station

3

Station

4

Material

and/or

labor

Statio

n

1

Material

and/or

labor

Material

and/or

labor

Material

and/or

labor

Used for Repetitive or Continuous Processing

23



Cellular Layouts

– machines are grouped into a cell that can processitems that have similar processing requirements

– Based on Group technology which involvesgrouping items with similar design or manufacturing

characteristics into part families Could be considered as mini product layouts

Can improve and simplify a functional/processlayout

Flexible Duplicates some resources

24



Original Process Layout

CA B Raw materials

Assembly

1

2

3

4

5

6 7

8

9

10

11

12

25



Cellular Layout

3

6

9

Assembly

12

4

8 10

5

7

11

12

A B C

Raw materials

Cell 1 Cell 2 Cell 3

26



• Workers

• Inventory

• Storage space

• Material handling

• Aisles

• Scheduling

• Layout decision

•

Goal

• Advantage

Limited skills

Low in-process, high

finished goods

Small

Fixed path (conveyor)

Narrow

Line balancing (Easier)

In-line, U-type

Equalize work at eachstation

Efficiency

Process

Comparison of Product and Process Layouts

High skills

High in-process, low

finished goods

Large

Variable path (forklift)

Wide

Dynamic (More difficult)

Functional

Minimize materialhandling cost

Flexibility

Product

27



Product Volume and Variety

Product

Layouts

Fixed

PositionLayouts Mixed Layouts Process Layouts

Quantity

Number of Different Products

Cellular

28



Product Flow Control

Batch Processing (Process Layout)• From a couple to several thousands identical parts

• A batch for each different part type

• Move together through the production system

• May split for material handling or to reduce processingtime

Examples are clothing, furniture production

Repetitive or Flow processing (Product Layout)

• Continuous – chemicals, foods, pharmaceuticals

• Discrete – car, refrigerator production

29



Production System Decision Hierarchy

Inputs Process Outputs Length of

Planning

Horizon

Long Range Economic Forecasts

Financial Choices

Strategic

Planning

Operating Facilities

Product Line (Families)

Technologies

Years

Processing Technologies/Efficiency

Medium Range Product

Family Forecasts Machine Schedules

Aggregate

Production

Planning

Production Level

Workforce Level

Family Inventories

Months

Production Levels

Workforce Levels

Current Inventory Status

Changeover Times and Costs

Item Forecasts

Disaggregation Master Production Schedule

(MPS) - Final Assembly by item

Item Inventories

Weeks

MPS

Bill of Materials

Process Plans

Production

Scheduling

Job Priorities

Order Releases

Machine Schedules

Days-Shift

Labor Status

Machine Status

Job Priorities

Order Releases

Machine Schedules

Shop Floor

Control

Machine Priorities

Job Status

Labor Reporting

Material Handling Tasks

Load/Prices/Unload Authorization

Real Time –

Minutes



QUESTIONS???

31

ie305 ch 2 production systems

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