MANUFACTURING

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MANUFACTURING
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Introduction

• Consumers are people who buy and use the items
  made in factories soap, food, shoes, cars, and
  books
• Industrial revolution in late 1700s new methods
  of manufacturing
• The first factories in the world made textiles in
  England and Scotland between 1750 and 1800
• Factorys power usually came from rivers that
  turned water wheels
• James Watt later designed a steam engine that
  could operate machines in factories
• Manufacturing is the application of physical and
  chemical processes to alter the geometry,
  properties, and/or appearance of a starting
  material (raw or semi finished) to make parts or
  products
• Manufacturing also includes assembly of multiple
  parts to make products
• A sequence of operations adds value to the
  material by changing its shape or properties

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Introduction
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Manufacturing Industries

• An industry/company may not span the whole cycle
  of manufacturing crude raw material to the
  finished product
• Industry consists of enterprises and
  organizations that produce or supply goods and
  services
• Industries can be categorized as basic producers,
  converter or fabricator and service industries
• The first three categories form a connecting
  chain
• Basic producers cultivate and exploit natural
  resources and transform these into raw materials
  e.g. steel producers
• Converters take the output of the basic producer
  and transform these raw materials into various
  industrial products and some consumer items
  e.g. producers of sheet-metals and plastics
• Fabricators fabricate and assemble final products
  e.g. manufacturers of automobiles, appliances
  and garments

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Manufacturing Industries

• Service industry works in parallel with the other
  three and constitutes the service sector of the
  economy

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Manufacturing Industries

• Another classification of manufacturing firms may
  be by the quantity of the products they make
• Job shop production, batch production and mass
  production

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Resources for Manufacturing

• Companies use a complex but coordinated setup of
  all the basic resources
• People
• Large companies employ a huge workforce because
  they manufacture several products at the same
  time
• People to put forward the requirement of a new
  product
• Research engineers and design engineers/drafters
• Development engineers decide the steps of
  manufacturing the product
• They make a prototype (a test version of the
  product ) of the new product before going onto
  the full scale or mass production
• Production engineers implement the plan given by
  development department
• Hundreds of laymen workers work in the production
  department
• These workers may be working on or repairing and
  maintaining the machines
• Skilled and qualified people are required for
  quality control
• Planning, managing warehouses, dispatching etc
• Marketing and distribution of the product in the
  local and international markets

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Resources for Manufacturing

• Information
• Trends in the market
• Different type of materials, their costs and
  quality standards
• Mechanical drawings of different parts
• Knowledge of manufacturing processes
• Companies may launch new research projects in
  collaboration with universities
• Materials
• It is not always a raw material materials in
  the natural state, e.g. iron ore, trees, and
  cotton
• Steel sheets come from iron ingots made from
  coal, limestone and iron ore
• Companies often make a trade-off between the cost
  and the quality of a material

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Resources for Manufacturing

• Tools and Machines
• A tool changes the shape of material or fastens
  it together
• Hand tools are those that use the power of our
  hand or arm hammer and pliers
• A power tool uses a small motor and is usually
  held in our hands Electric drills
• Jigs and fixtures facilitate the process of
  manufacturing devices used to locate and hold
  work pieces.
• Machines are usually operated by electric motors
  bending, cutting, drilling, grinding, and
  hammering
• Modern manufacturing processes run under program
  and feedback control

A jig used in carpentry shop
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Resources for Manufacturing

• Energy
• Mostly in the form of electricity
• Thermal power electricity from fossil fuels,
  i.e. coal, oil and natural gas
• Own power source or near the government power
  supply low transmission costs
• A chemical plant can use its waste heat energy to
  generate steam co-generation
• Capital
• Buy land, build factories, purchase equipment,
  pay workers, maintain machines, and advertise
  their products
• A company may sell shares of stock
• Capital may also come from a venture capitalist
• Venture capital is money used to finance the
  costs of starting a new company
• Time
• Productivity is how quickly and cheaply a product
  is made
• F. W. Taylor suggested the idea of scientific
  management study every movement that a worker
  made

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Industrial Materials

• Four basic categories metals, ceramics wood and
  polymers
• Other useful materials are natural
  rubber/leather, glass, cotton, silk and wool
• Criteria for selecting the right material
  properties of the material, its
  deterioration-rate and its cost
• Manufacturing process that can be used to make
  products depend on the mechanical and physical
  properties of the materials
• Metals
• Alloys are composed of two or more elements
• Metals 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, chromium 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 )
• Gray cast iron is used in blocks and heads of
  internal combustion engines

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Industrial Materials

• Ceramics
• Compounds of metallic (or semi metallic) and
  nonmetallic elements oxygen, nitrogen, ad
  carbon
• Traditional ceramics clay for brick, tile and
  pottery, silica for glass products and alumina
  and silicon carbide for abrasives used for
  grinding
• Newer ceramics tungsten carbide and titanium
  carbide for cutting tools and grinding abrasives
• Crystalline ceramics are formed from powders and
  then sintered
• Sintering heating to a temperature below the
  melting point to achieve bonding between the
  powders

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Industrial Materials

• Wood
• Natural wood can be classified into two forms
  hardwood and softwood
• Hardwood trees that lose their leaves in
  winter, such as maple, oak and walnut
• Softwood evergreen trees such as fir, pine and
  redwood
• Plywood is made by gluing together a number of
  thin veneers or plies of softwood or hardwood.
  There is always an odd number of veneers
• Hardboard is made from wood fiber extracted from
  chips and pulped wood waste a cheaper option
  than plywood

Plywood
Hardboard
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Industrial Materials

• Polymers
• A compound formed of repeating structural units
• They consist of carbon plus one or more other
  elements such as hydrogen, nitrogen, oxygen, and
  chlorine
• Thermoplastic polymers soften when heated and
  when cooled, they are hard again polyethylene
  bags, PVC pipes and nylon
• Thermoset polymers char and burn when heated
  plastic cups and dishes made of melamine.