MANUFACTURINGMANUFACTURING

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IntroductionIntroduction Consumers are people who buy and use the items made in factories – Consumers are people who buy and use the items made in factories –

soap, food, shoes, cars, and bookssoap, food, shoes, cars, and books Industrial revolution in late 1700s – new methods of manufacturingIndustrial revolution in late 1700s – new methods of manufacturing The first factories in the world made textiles in England and The first factories in the world made textiles in England and

Scotland between 1750 and 1800Scotland between 1750 and 1800 Factory’s power usually came from rivers that turned Factory’s power usually came from rivers that turned water wheelswater wheels James Watt later designed a steam engine that could operate James Watt later designed a steam engine that could operate

machines in factoriesmachines in factories ManufacturingManufacturing is the application of physical and chemical processes is the application of physical and chemical processes

to alter the geometry, properties, and/or appearance of a starting to alter the geometry, properties, and/or appearance of a starting material (raw or semi finished) to make parts or productsmaterial (raw or semi finished) to make parts or products

Manufacturing also includes assembly of multiple parts to make Manufacturing also includes assembly of multiple parts to make productsproducts

A sequence of operations adds value to the material by changing its A sequence of operations adds value to the material by changing its shape or propertiesshape or properties

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IntroductionIntroduction

Manufacturing Process

Starting

Material

Processed

PartP

eop

le

Info

rmati

on

Mate

rials

Tools

&

Mach

ines

Cap

ital

En

erg

y

Tim

e

Raw Material Product Raw Material Product Cotton Thread Animal Hides Shoes Wood Paper Sand Glass Iron Ore Steel Steel Structures Petroleum Plastic Plastic Patio Chairs

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Manufacturing IndustriesManufacturing Industries An industry/company may not span the whole cycle of An industry/company may not span the whole cycle of

manufacturing – crude raw material to the finished product manufacturing – crude raw material to the finished product Industry consists of enterprises and organizations that Industry consists of enterprises and organizations that

produce or supply goods and servicesproduce or supply goods and services Industries can be categorized as basic producers, Industries can be categorized as basic producers,

converter or fabricator and service industriesconverter or fabricator and service industries The first three categories form a connecting chainThe first three categories form a connecting chain Basic producersBasic producers cultivate and exploit natural resources and cultivate and exploit natural resources and

transform these into raw materials – e.g. steel producerstransform these into raw materials – e.g. steel producers ConvertersConverters take the output of the basic producer and take the output of the basic producer and

transform these raw materials into various industrial transform these raw materials into various industrial products and some consumer items – e.g. producers of products and some consumer items – e.g. producers of sheet-metals and plasticssheet-metals and plastics

FabricatorsFabricators fabricate and assemble final products – e.g. fabricate and assemble final products – e.g. manufacturers of automobiles, appliances and garmentsmanufacturers of automobiles, appliances and garments

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Manufacturing IndustriesManufacturing Industries Service industryService industry works in parallel with the other three and works in parallel with the other three and

constitutes the service sector of the economyconstitutes the service sector of the economy

Basic Producers

Converters and Fabricators Service

Agriculture Aerospace Appliances Repair/Maintenanc

e

Petroleum Automotive Pharmaceuticals

Education

Fishing Beverages Publishing Hotel

Mining Chemicals Textiles Tourism

Forestry Electronics Tire and Rubber

Transportation

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Manufacturing IndustriesManufacturing Industries Another classification of manufacturing firms may be by the Another classification of manufacturing firms may be by the

quantity of the products they makequantity of the products they make Job shop production, batch production and mass productionJob shop production, batch production and mass production

Job Shop Batch Production Mass Production Production quantity Low Medium High Production rate Low Medium High Labor skill level High Medium Low

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Resources for Resources for ManufacturingManufacturing

Companies use a complex but coordinated setup of all the basic Companies use a complex but coordinated setup of all the basic resourcesresources

PeoplePeople– Large companies employ a huge workforce because they manufacture Large companies employ a huge workforce because they manufacture

several products at the same timeseveral products at the same time– People to put forward the requirement of a new productPeople to put forward the requirement of a new product– Research engineers and design engineers/draftersResearch engineers and design engineers/drafters– Development engineers decide the steps of manufacturing the productDevelopment engineers decide the steps of manufacturing the product– They make a prototype (a test version of the product ) of the new product They make a prototype (a test version of the product ) of the new product

before going onto the full scale or mass productionbefore going onto the full scale or mass production– Production engineers implement the plan given by development Production engineers implement the plan given by development

departmentdepartment– Hundreds of laymen workers work in the production departmentHundreds of laymen workers work in the production department– These workers may be working on or repairing and maintaining the These workers may be working on or repairing and maintaining the

machinesmachines– Skilled and qualified people are required for quality controlSkilled and qualified people are required for quality control– Planning, managing warehouses, dispatching etcPlanning, managing warehouses, dispatching etc– Marketing and distribution of the product in the local and international Marketing and distribution of the product in the local and international

marketsmarkets

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Resources for Resources for ManufacturingManufacturing

InformationInformation– Trends in the marketTrends in the market– Different type of materials, their costs and quality standardsDifferent type of materials, their costs and quality standards– Mechanical drawings of different partsMechanical drawings of different parts– Knowledge of manufacturing processesKnowledge of manufacturing processes– Companies may launch new research projects in collaboration with Companies may launch new research projects in collaboration with

universitiesuniversities

MaterialsMaterials– It is not always a raw material – materials in the natural state, e.g. It is not always a raw material – materials in the natural state, e.g.

iron ore, trees, and cottoniron ore, trees, and cotton– Steel sheets come from iron ingots made from coal, limestone and Steel sheets come from iron ingots made from coal, limestone and

iron oreiron ore– Companies often make a trade-off between the cost and the quality Companies often make a trade-off between the cost and the quality

of a materialof a material

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Resources for Resources for ManufacturingManufacturing

Tools and MachinesTools and Machines– A tool changes the shape of material or fastens it togetherA tool changes the shape of material or fastens it together– Hand toolsHand tools are those that use the power of our hand or arm – are those that use the power of our hand or arm –

hammer and pliershammer and pliers– A power tool uses a small motor and is usually held in our hands – A power tool uses a small motor and is usually held in our hands –

Electric drills Electric drills – Jigs and fixturesJigs and fixtures facilitate the process of manufacturing – devices facilitate the process of manufacturing – devices

used to locate and hold work pieces.used to locate and hold work pieces.– Machines are usually operated by electric motors – bending, Machines are usually operated by electric motors – bending,

cutting, drilling, grinding, and hammering cutting, drilling, grinding, and hammering – Modern manufacturing processes run under program and Modern manufacturing processes run under program and

feedback controlfeedback control

A jig used in carpentry shop

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Resources for Resources for ManufacturingManufacturing

EnergyEnergy– Mostly in the form of electricityMostly in the form of electricity– Thermal power – electricity from fossil fuels, i.e. coal, oil and natural gasThermal power – electricity from fossil fuels, i.e. coal, oil and natural gas– Own power source or near the government power supply – low Own power source or near the government power supply – low

transmission coststransmission costs– A chemical plant can use its waste heat energy to generate steam – A chemical plant can use its waste heat energy to generate steam – co-co-

generationgeneration CapitalCapital

– Buy land, build factories, purchase equipment, pay workers, maintain Buy land, build factories, purchase equipment, pay workers, maintain machines, and advertise their productsmachines, and advertise their products

– A company may sell shares of stockA company may sell shares of stock– Capital may also come from a venture capitalistCapital may also come from a venture capitalist– Venture capitalVenture capital is money used to finance the costs of starting a new is money used to finance the costs of starting a new

companycompany TimeTime

– ProductivityProductivity is how quickly and cheaply a product is made is how quickly and cheaply a product is made– F. W. Taylor suggested the idea of F. W. Taylor suggested the idea of scientific managementscientific management – study every – study every

movement that a worker mademovement that a worker made

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Industrial MaterialsIndustrial Materials Four basic categories – metals, ceramics wood and polymersFour basic categories – metals, ceramics wood and polymers Other useful materials are natural rubber/leather, glass, cotton, Other useful materials are natural rubber/leather, glass, cotton,

silk and woolsilk and wool Criteria for selecting the right material – properties of the Criteria for selecting the right material – properties of the

material, its deterioration-rate and its costmaterial, its deterioration-rate and its cost Manufacturing process that can be used to make products depend Manufacturing process that can be used to make products depend

on the mechanical and physical properties of the materials on the mechanical and physical properties of the materials MetalsMetals

– Alloys are composed of two or more elementsAlloys are composed of two or more elements– Metals can be divided into two basic groups: (1) ferrous, and (2) nonferrousMetals can be divided into two basic groups: (1) ferrous, and (2) nonferrous– Steel contains 0.02 to 2.11 % carbon. It may also have manganese, Steel contains 0.02 to 2.11 % carbon. It may also have manganese,

chromium and nickel to enhance the properties of the metalchromium and nickel to enhance the properties of the metal– Cast iron is an alloy of iron, carbon (2 to 4 %) and silicon (0.5 to 3 %) Cast iron is an alloy of iron, carbon (2 to 4 %) and silicon (0.5 to 3 %) – Gray cast ironGray cast iron is used in blocks and heads of internal combustion engines is used in blocks and heads of internal combustion engines

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Industrial MaterialsIndustrial Materials CeramicsCeramics

– Compounds of metallic (or semi metallic) and nonmetallic Compounds of metallic (or semi metallic) and nonmetallic elements – oxygen, nitrogen, ad carbonelements – oxygen, nitrogen, ad carbon

– Traditional ceramics – Traditional ceramics – clayclay for brick, tile and pottery, for brick, tile and pottery, silicasilica for for glass products and glass products and alumina and silicon carbidealumina and silicon carbide for abrasives used for abrasives used for grindingfor grinding

– Newer ceramics – Newer ceramics – tungsten carbide and titanium carbidetungsten carbide and titanium carbide for for cutting tools and grinding abrasivescutting tools and grinding abrasives

– Crystalline ceramics are formed from powders and then sintered Crystalline ceramics are formed from powders and then sintered – Sintering – heating to a temperature below the melting point to Sintering – heating to a temperature below the melting point to

achieve bonding between the powdersachieve bonding between the powders

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Industrial MaterialsIndustrial Materials WoodWood

– Natural wood can be classified into two forms – hardwood and Natural wood can be classified into two forms – hardwood and softwood softwood

– HardwoodHardwood – trees that lose their leaves in winter, such as maple, – trees that lose their leaves in winter, such as maple, oak and walnutoak and walnut

– Softwood – evergreen trees such as fir, pine and redwoodSoftwood – evergreen trees such as fir, pine and redwood– PlywoodPlywood is made by gluing together a number of thin veneers or is made by gluing together a number of thin veneers or

plies of softwood or hardwood. There is always an odd number of plies of softwood or hardwood. There is always an odd number of veneersveneers

– Hardboard is made from wood fiber extracted from chips and Hardboard is made from wood fiber extracted from chips and pulped wood waste – a cheaper option than plywoodpulped wood waste – a cheaper option than plywood

Plywood Hardboard

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Industrial MaterialsIndustrial Materials PolymersPolymers

– A compound formed of repeating structural unitsA compound formed of repeating structural units– They consist of carbon plus one or more other elements such as They consist of carbon plus one or more other elements such as

hydrogen, nitrogen, oxygen, and chlorinehydrogen, nitrogen, oxygen, and chlorine– ThermoplasticThermoplastic polymers soften when heated and when cooled, polymers soften when heated and when cooled,

they are hard again – polyethylene bags, PVC pipes and nylonthey are hard again – polyethylene bags, PVC pipes and nylon– ThermosetThermoset polymers char and burn when heated – plastic cups polymers char and burn when heated – plastic cups

and dishes made of melamine.and dishes made of melamine.