Transcript Lecture 3 - Process

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
Types of production systems
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Factors Influencing Process Choices

Volume: Average quantity of the products produced in a
manufacturing system
–
–
–

Variety: Number of alternative products and variants of each
product that is offered by a manufacturing system
–

Low volume: Turnkey project management firms such as L&T and BHEL
High volume: Consumer non-durable and FMCG sector firms, Automobile,
Chemical Processing
Mid-volume: Consumer durables, white goods and several industrial
products
Variety of product offerings is likely to introduce variety at various
processes in the system; alternative production resources, materials, and
skill of workers (Titan ,Telco)
Flow: Flow indicates the nature and intensity of activities
involved in conversion of components and material from raw
material stage to finished goods stage
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Relationship between volume and variety
Volume
Mass
Production
Petrochemicals,
Automobile
Variety
Mid volume
Mid variety
Motor Manufacturing
Pharmaceuticals
Project
Organisations
Turnkey Project
Execution
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Processes & Operations Systems
Available Alternatives

Three types of flows occur in operating
systems:
– Continuous
– Intermittent
– Jumbled
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Types of industries
Basic
Industries
Manufacturing
Discrete
Process
Services
Project
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Paper Manufacturing
An example of process industry
Logs and chips
of wood stored
Processing of
the wood
Crushing of
logs and chips
Preparatory
Drying the
wood pulp
Refining the
Wood pulp
Pulp making
Stretching
Paper rolling
Cutting
Final packing
Paper making
Cleaning &
Bleaching
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Continuous Flow System
Mass production in discrete manufacturing

In discrete manufacturing various components are
manufactured in discrete fashion and the final product is
obtained through an assembly process

In a mass production system, the volume of production is very
high and the number of variations in the final product is low
–

Examples:
»
Automobile and two wheeler manufacturers,
»
Manufacturers of electrical components such as switches and health care
products such as disposable syringes
The entire manufacturing is organised by arranging the
resources one after the other as per the manufacturing
sequence (known as product line structure)
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Intermittent Flow System



Characterised by mid-volume, mid-variety
products/services
Increases the flow complexities
Flow and capacity balancing are difficult but
important
– Process industries use batch production methods
– Discrete industries use alternative methods of
designing layout issues


Capacity Estimation is hard
Production Planning & Control is complex
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Jumbled Flow System



Occurs on account of non-standard and complex flow
patterns characteristic in certain systems
–
Highly customised items
–
customer orders for one or a few
Examples
–
turnkey project executor such as BHEL or L&T
–
customised manufacturing systems such as PCB
fabricators, sheet metal fabricators, tool room operators and
printing and publishing
Operational complexity arising out of jumbled flow is
high
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Types of Production systems
Job Shop
Type of
Production
Flow
Continuous
Production
Types of
Production
Systems
Mass
Production
Batch Type
of
Production
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Types of Production Systems
Job Shop Type of Production


as per Customer demand, e.g. heavy m/c s,
low volume –high variety.

Use of general purpose m/cs

Highly skilled operators

Large inventory of material, tools, parts.

Detailed planning required.

Limitations high cost, production planning is
complicated
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Batch Type of Production:
Lot Production of similar items – job passes
through the functional departments in lots or
batches. E.g : medicines.

Shorter production runs.

Plant and machinery are flexible.

Better utilization of plant and machinery

Limitations – production planning becomes
complex.
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Mass Production :
manufacture of discrete parts and accessories using
a continuous process is called mass production,
Demand pattern known, Standard product, Large
batches. Dedicated assembly lines. lines, E.g :TV
•Higher rate of production.
•Higher capacity utilization.
•Less skilled operators are required.
•Manufacturing cost per unit is low.
•Limitations ; breakdown of one m/c will stop
entire prodn line.
High investment.
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Flow /Continuous Production :
production facilities are arranged as per sequence
of operations. Material is made to flow through
sequence of e.g. Cement, Petrol/Diesel

Dedicated plant and machinery with Zero
flexibility.

Material handling is fully automated.

Planning and scheduling is routine action.

High volume of production.
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Manufacturing Reference Model
Low volume
D
I
S
C
R
E
T
E
JOB/ASSEMBLY
Machine-Tools
Farming Equipments
Shutters
Jewelry
HIGH VOLUME/
REPETITIVE
Electronic
Components
Spinning Mills
Batteries
Tyres
BATCH/MIX
Food
Beverages, Wine
Dairy Products
Pharmaceuticals
Paint
PROCESS/FLOW
Refineries
Glass
Graphite
Paper Mills
Steel
Fertilizers
High Volume
P
R
O
C
E
S
S
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Product – Process Matrix
Low Volume
Low Standardisation
One of a kind
Jumbled
Flow
(Job Shop)
None
Machine Tools
Connected Line
Flow (Assembly
Line)
.
High Volume
Few Major Products
High Standardisation
Higher Volume
Commodity Products
Satellite Launch
Vehicle
Disconnected
Line Flow
(Batch)
Continuous
Flow
Multiple Products
Low Volume
Auto electric
parts
None
Polyethylene
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Manufacturing Strategies
raw materials components semi finished finished goods
eng
prod
prod
prod
make-to-stock
s
assemble-to-order
u
p
p
make-to-order
l
i
e engineer-to-order
r
standard
customer driven
c
u
s
t
o
m
e
r