2. WHAT IS MANUFACTURING?
• The word manufacture is derived from two Latin words
manus (hand) and factus (make); the combination
literally means “made by hand”.
• “Made by hand” accurately described the fabrication
methods that were used when the English word
“manufacture” was first coined around 1567 A.D.
• Most modern manufacturing operations are
accomplished by mechanized and automated equipment
that is supervised by human workers
• It encompasses: Design of the product, Raw material
selection, choosing the sequence of processes for
making items.
3. Is Manufacturing Important?
• Making things has been an essential human
activity since before recorded history.
• Today, the term manufacturing is used for this
activity.
• Manufacturing is important to most of developed
and developing nations in two ways:
– Technologically
– Economically
4. Manufacturing: Technological
• Application of physical and chemical processes
to alter the geometry, properties, and/or
appearance of a starting material to make
parts or products
5. Technological Importance
• Technology - the application of science to
provide society and its members with those
things that are needed or desired.
• Technology provides the products that help our
society and its members live better.
• What do these products have in common?
– They are all manufactured.
• Manufacturing is the essential factor that
makes technology possible.
6. Manufacturing - Economical
• Transformation of materials into items of
greater value by one or more processing
and/or assembly operations
7. Economic Importance
• Manufacturing has the important function of
adding value to products i.e. marketable price.
• In general, higher the standard of living, higher
is the level of manufacturing activity in a
country.
U.S. Economy
Sector: %GDP
Agriculture and natural resources 5
Construction and public utilities 5
Manufacturing 15
Service industries 75
100
10. Manufacturing Industries
• Industry consists of enterprises and organizations
that produce or supply goods and services.
• Industries can be classified as:
1. Primary industries - cultivate and exploit natural
resources, e.g., agriculture, mining
2. Secondary industries - take the outputs of
primary industries and convert them into
consumer and capital goods e.g. aerospace,
automobile
3. Tertiary industries - service sector e.g. Banking,
Insurance
12. Manufacturing Industries
• Secondary industries include manufacturing,
construction, and electric power generation.
• Manufacturing includes several industries whose
products are not covered in this book; e.g., apparel,
beverages, chemicals, and food processing.
• For our purposes, manufacturing means production
of components/hardware e.g.
– Nuts and bolts, forgings, cars, airplanes, digital
computers, plastic parts, and ceramic products
13. Manufactured Products
• Final products divide into two major classes:
1. Consumer goods - products purchased directly by
consumers
– Cars, clothes, TVs, tennis rackets
2. Capital goods - those purchased by companies to
produce goods and/or provide services
– Aircraft, computers, communication equipment,
medical apparatus, trucks, machine tools,
construction equipment
14. Production Quantity Q
• The quantity of products Q made by a factory has
an important influence on the way its people,
facilities, and procedures are organized.
• Annual quantities can be classified into three ranges:
Production type Quantity
Low production Job production 1-to 100
Medium production Batch production 100 to 10000
High production Mass production 10000 to millions
15. Product Variety P
• Product variety P refers to different product types or
models produced in the plant.
• Different products have different features.
– They are intended for different markets
– Some have more parts than others
• The number of different product types made each year
in a factory can be counted.
•When the number of product
types made in the factory is
high, this indicates high
product variety.
16. Manufacturing Capability
• A manufacturing plant consists of processes and
systems (and people) to transform a certain limited
range of materials into products of increased value
• The three building blocks - materials, processes, and
systems - are the subject of modern manufacturing.
• Manufacturing capability includes:
1. Technological processing capability
2. Physical product limitations
3. Production capacity
17. 1. Technological Processing Capability
• It means set of available manufacturing processes in
the plant (or company) to make products.
• Certain manufacturing processes are suited to certain
materials, so by specializing in certain processes, the
plant is also specializing in certain materials.
• Includes not only the physical processes, but also the
expertise of the plant personnel
• In simple term technological processing capability can
be understood from following examples:
– A machine shop cannot roll steel
– A steel mill cannot build cars
18. 2. Physical Product Limitations
• Given a plant with a certain set of processes, there
are size and weight limitations on the parts or
products that can be made in the plant.
• Product size and weight affect:
– Production equipment
– Material handling equipment
• Production, material handling equipment, and plant
size must be planned for products that lie within a
certain size and weight range
19. 3. Production Capacity
• Defined as the maximum quantity that a plant can
produce in a given time period (e.g., month or
year) under assumed operating conditions
• Operating conditions refer to number of shifts
per week, hours per shift, direct labor manning
levels in the plant, and so on
• Usually measured in terms of output units, such as
tons of steel or number of cars produced by the
plant.
– Also called plant capacity
23. How Many Manufactured
Components In Products?
• Products around us consist of numerous individual pieces that
shall be built and assembled:
• Single components products :nail, bolt, fork, coat hanger, etc.
• Assembled products :ball point pens, automobiles, washing m/c
1. Clip, pin : one part
2. Lawn mower :300 parts
3. Grand piano :12,000 parts
4. Automobile :15,000 parts
5. Boeing 747-400: 6 million parts
24. How Many Materials In Products?
• A product requires use of many
materials with desirable properties to
make different parts.
25. Range of Materials &
Processes in a Tractor
John Deere (Model 8430) tractor, with detailed illustration of its diesel
engine, showing the variety of materials and processes incorporated.
26. Materials In An Automotive
Engine
Ford,DuratecV-6Engine-showingvarious
components&materialsusedinmakingthem.
27. Materials & Processes In
All-Aluminum Automobile
The aluminum body structure, showing various components
made by extrusion, sheet forming, and casting processes.
28. Fig: Examples of the wide
variety of materials and
geometries for paper clips.
Some for consideration:
• Functional requirements.
• What material properties
are required?
• What manufacturing
attributes are required?
• Would the material and
processing strategy
change if the desired
quantity was 10,000 vs. 1
million per day?
Example:1
Manufacturing Paper Clip
29. Example:1
Manufacturing Paper Clip
General considerations:
1. What type of material? Metallic or non metallic?
2. If metal what kind of metal?
3. If the material is wire then what should be its diameter?
4. Should it be round or have some other x-section?
5. Is the wire’s surface finish & appearance important? What should it
be its roughness?
6. How would you take a piece of wire & shape it into a paper clip?
7. Would you do it by hand? If not , what kind of machine should you
design or purchase to make paper clips?
8. If, as the owner of a company, you were given an order for 100 parts
vs for a million parts, would your approach to mfg be different?
Functional and Service Requirement:
1. Clamping force, Permissible plastic deformation, corrosion etc.
2. Relation between mechanical properties (stiffness) & wire diameter.
3. What should be the yield strength of wires? (If too low, clip will
bend permanently.)
4. Life, customer satisfaction
30. Material Selection
1. Material selection requires knowledge of function and service
requirements of the product.
2. Therefore, choosing materials that are commercially available.
3. Corrosion resistance must also be considered
Style & Appearance,
1. Metallic or plastic? What shape (round or else)?
2. Surface finish, surface finish
Production Requirements:
1. How to shape (hand or machine)? Batch quantity
2. Bending without cracking or breaking?
3. Is wire cut easily without causing excessive wear on tooling?
4. Are edges on the wire smooth (burs not desire)?
5. What is the most economical method of mfg this part at the
desired production rate?
Example:1
Manufacturing Paper Clip
31. Example:2
MANUFACTURING of LIGHT BULB
Some informations:
1. 60W bulb has thin Wire (0.045 mm dia)
2. 1% decrease in wire diameter,
shortens bulb life by 25%.
3. Filament is heated to 2200 to 3000
0C.
4. Requires inert environment/ vacuum.
5. Bulb vacuumed or filled with N2 or
Argon Moisture causes 0.5m
blackened spot.
6. Production Rate >1000/Min.
32. Example 2: Steps In Making
incandescent Light Bulbs
Fig a Components of a common
incandescent light bulb.
Fig b Manufacturing steps
in making an incandescent
light bulb
33. Example 3:
Baseball Bat Cross-sections
Fig: X-sections of baseball bats
Top portion is made of
aluminum while bottom
portion is made of
composite material
34. Example 4: Sunglasses Mold
• An excellent example of machining complexity and use
computer in manufacturing.
(a) Computer model of the
sunglass as designed and
viewed on the monitor.
(b) Machine the die cavity
using a CNC milling machine
(c) Final product
35. Change In Materials
• Materials used undergone changes throughout history
due to periodic material shortages and the cost of
appropriate raw materials. e.g. U.S. Pennies.
Time Period Materials Used
1793-1837 100% copper
1837-1857 95% copper, 5% tin and zinc
1857-1863 88% copper, 12% nickel
1864-1962 95% copper, 5% tin and zinc
1943(WW II year) Steel, plated with zinc
1962-1982 95% copper, 5% zinc
1982-present 97.5% zinc, plated with copper
36. Materials in Manufacturing
• Most engineering materials can be classified into
one of three basic categories:
1. Metals
2. Ceramics
3. Polymers
• Their chemistries are different, and their
mechanical and physical properties are different.
• These differences affect the manufacturing
processes that can be used to produce products
from them
37. Methods of Manufacture
FIG: Various methods of making a simple part:
(a) casting or powder metallurgy, (b) forging or upsetting,
(b) (c) extrusion, (d) machining, (e) joining two pieces.
• A product can be made using from many materials and
various methods
39. Scales in Manufacturing
FIG: Illustration of the
range of common sizes of
parts and the capabilities
of manufacturing processes
in producing these parts.
42. Selection of Manufacturing Process
• Type of basic manufacturing process mainly depends on:
1. Type of the Work Material
2. Nature (i.e. ductile or brittle) and its Hardness
3. Melting Temperature of the Work Material
4. Production Volume or Batch Size of the Production
• Basic nature of the manufacturing process affects the
1. Cost
2. Properties and
3. Characteristics of the Final Product
43. Application Range of Manufacturing
Processes According to Melting Temp
of Materials & Batch Size
45. How to Select Processes
Some guidelines for selection of basic manufacturing process:
[A] According to the Batch Size:
• Smaller batch size requires flexible manufacturing
processes like machining, which can produce variety of
geometrical features. (up to 500 products).
1. Larger batch size allows use of primary forming and
deforming processes so as to offset the relatively high
costs of machine tools and tooling.
Primary forming processes from 75 onwards.
Deforming processes more than 1000.
46. Classification of
Manufacturing Processes
• All the Manufacturing Processes can be Put into Basic SIX
Categories according to their Nature:
1. Primary Forming Processes [Additive or Accretion]
2. Material Removal or Machining [Subtractive]
3. Deforming Processes [Formative]
4. Joining or Fabrication or Consolidation [Assembling]
5. Finishing and Surface Treatment Processes
6. Bulk Property Enhancing Processes [Heat Treatment]
• All These SIX Categories can be Sub-divided into TWO Sub-categories
1. Conventional
2. Unconventional or Advanced
47. Manufacturing Processes
Two basic types:
1. Processing operations - transform a work
material from one state of completion to a
more advanced state
– Operations that change the geometry,
properties, or appearance of the starting
material
2. Assembly operations - join two or more
components to create a new entity
48.
49. Processing Operations
• Alters a material’s shape, physical properties, or
appearance in order to add value
• Three categories of processing operations:
– Shaping operations - alter the geometry of the
starting work material
– Property-enhancing operations - improve physical
properties without changing shape
– Surface processing operations - clean, treat,
coat, or deposit material on surface of work
50. Shaping Processes
Basically there are four shaping processes:
1. Solidification processes - starting material is a heated
liquid or semifluid
2. Particulate processing - starting material consists of
powders
3. Deformation processes - starting material is a ductile
solid (commonly metal)
4. Material removal processes - starting material is a
ductile or brittle solid
51. Solidification Processes
• Starting material is heated sufficiently to
transform it into a liquid or highly plastic
state.
• Casting process at left and casting product at
right.
52. Particulate Processing
• (1) Starting materials are metal or ceramic
powders, which are (2) pressed and (3)
sintered .
53. Deformation Processes
• Starting workpart is shaped by application of
forces that exceed the yield strength of the
material
• Examples: (a) forging and (b) extrusion
54. Material Removal Processes
• Excess material removed from the starting
piece so what remains is the desired geometry
• Examples: (a) turning, (b) drilling, and (c) milling
55. Property Enhancing Processes
Processes that improve mechanical or physical
properties of work material.
• Examples:
– Heat treatment of metals and glasses
– Sintering of powdered metals and ceramics
• Part shape is not altered, except unintentionally
– Example: unintentional warping of a heat treated
part
56. A batch of silicon wafers enters a furnace heated to
1000°C (1800°F) during fabrication of integrated circuits
under clean room conditions (photo courtesy of Intel
Corporation).
57. Surface Processing Operations
• Cleaning - chemical and mechanical processes
to remove dirt, oil, and other surface
contaminants
• Surface treatments - mechanical working such
as sand blasting, and physical processes like
diffusion
• Coating and thin film deposition - coating
exterior surface of the workpart. Examples:
– Electroplating
– Physical vapor deposition
– Painting
58. Photomicrograph of
the cross section of
multiple coatings of
titanium nitride and
aluminum oxide on a
cemented carbide
substrate (photo
courtesy of
Kennametal Inc.).
59. Assembly Operations
• Two or more separate parts are joined to form
a new entity.
• Types of assembly operations:
1. Joining processes – create a permanent joint
• Welding, brazing, soldering, adhesive bonding
2. Mechanical assembly – fastening by mechanical
methods
• Threaded fasteners (screws, bolts and nuts);
press fitting, expansion fits
60. Two welders
perform arc welding
on a large steel pipe
section (photo
courtesy of Lincoln
Electric Company).
62. Production Machines and Tooling
• Manufacturing operations are accomplished using
machinery and tooling (and people).
• Types of production machines:
– Machine tools - power-driven machines used
to operate cutting tools previously operated
manually
– Other production equipment:
• Presses
• Forge hammers,
• Plastic injection molding machines
63. Production Systems
• People, equipment, and procedures used for the
materials and processes that constitute a firm's
manufacturing operations .
• A manufacturing firm must have systems and
procedures to efficiently accomplish its
production
• Two categories of production systems:
– Production facilities
– Manufacturing support systems
• People make the systems work
64. Production Facilities
• The factory, production equipment, and material
handling systems.
• Includes the way the equipment is arranged in the
factory - the plant layout
• Equipment usually organized into logical groupings,
called manufacturing systems. Examples:
– Automated production line
– Machine cell consisting of an industrial robot and two
machine tools
• Production facilities "touch" the product
65. Machine cell consisting of two horizontal machining
centers supplied by an in-line pallet shuttle.
66. Facilities vs Product Quantities
• A company designs its manufacturing systems
and organizes its factories to serve the
particular mission of each plant.
• Certain types of production facilities are
recognized as most appropriate for a given
type of manufacturing:
1. Low production – 1 to 100
2. Medium production – 100 to 10,000
3. High production – 10,000 to >1,000,000
67. Low Production
• Job shop is the term used for this type of
production facility
• A job shop makes low quantities of specialized
and customized products
– Products are typically complex, e.g., space capsules,
prototype aircraft, special machinery
– Equipment in a job shop is general purpose
– Labor force is highly skilled
– Designed for maximum flexibility
69. Medium Production
• Two different types of facility, depending on product variety:
• Batch production
– Suited to medium and hard product variety
– Setups required between batches
• Cellular manufacturing
– Suited to soft product variety
– Worker cells organized to process parts without
setups between different part styles
72. High Production
• Often referred to as mass production
– High demand for product
– Manufacturing system dedicated to the
production of that product
• Two categories of mass production:
1. Quantity production
2. Flow line production
73. Quantity Production
• Mass production of single parts on single
machine or small numbers of machines
• Typically involves standard machines equipped
with special tooling
• Equipment is dedicated full-time to the
production of one part or product type
• Typical layouts used in quantity production are
process layout and cellular layout
74. Flow Line Production
• Multiple machines or workstations arranged in
sequence, e.g., production lines
• Product is complex
– Requires multiple processing and/or assembly
operations
• Work units are physically moved through the
sequence to complete the product
• Workstations and equipment are designed
specifically for the product to maximize
efficiency
76. Assembly workers on an
engine assembly line
(photo courtesy of Ford
Motor Company).
77. Manufacturing Support Systems
• A company must organize itself to design the
processes and equipment, plan and control
production, and satisfy product quality
requirements
– Accomplished by manufacturing support systems
• The people and procedures by which a company manages
its production operations
• Typical departments:
– Manufacturing engineering, Production planning and
control, Quality control
87. Manufacturing Processes: Joining
Figure I.7f Schematic illustration of various joining processe
Additive Processes
• Processes
– Rapid Prototyping
• Very flexible to part shape;
usually limited in material
choices; slow rates; fully automated
– Advanced Composites Processes
• Combination of additive and net
shape processes
– Microelectronics Processes
• Physical and chemical vapor
deposition processes and
coating methods
– Joining & Assembly
• Broad category includes welding,
adhesives, and mechanical
88. Laser Cutting
Figure I.8 Cutting sheet metal with a
laser beam. Source: Courtesy of
Rofin-Sinar, Inc. and Manufacturing
Engineering Magazine, Society of
Manufacturing Engineers
90. Manufacturing of Hip
Replacement
Figure 1.10 (a) Manufacturing steps in the production of a roll-
formed and machined total hip replacement stem; (b)
Manufacturing steps in the production of a forged stem. Hip
stems can also be produced by investment casting, metal injection
91. Microscopic Components
Figure I.11 (a) Microscopic gears with dust mite. Source:
Courtesy Sandia National Laboratory; (b) A movable
micromirror component of a light sensor. Source: Courtesy
of Richard Mueller, University of California at Berkeley.
92. Salt and Pepper Shakers
Figure I.12 A salt and pepper mill
set. The two metal pieces (at the
bottom) for the pepper mill are made
by powder-metallurgy techniques.
Source: Reproduced with
permission from Success Stories on
P/M Parts, Metal Powder Industries
Federation, Princeton, NJ, 1998.
