A1261516507PKsHk

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Energy and Environmental Issues in
Manufacturing 3/3/09
Amie Ruhl Lyndon Wong Martin Koh Teo Qing Ren Yue
Wei Chuan
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Topics Covered

• Casting
• Machining
• Lubricants and coolants
• Dry Machining
• Other Technology
• Case Study

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Casting

• Sales of 25 to 28 billion annually
• 2,480 metal casting facilities located throughout
  the United States
• Employing approximately 161,000 people
• Metal forming technique for 90 of all
  manufactured goods and for all machinery for
  manufacturing

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Casting Energy

• Energy consumption estimated to be 200 and 250
  trillion Btu
• Representing about 1 of all U.S. manufacturing
  energy use
• 55 of total energy costs can be attributed to
  melting

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Positive Actions

• 1.25 billion invested annually in pollution
  prevention technologies and in meeting
  environmental standards
• Uses scrap metal (for which it pays 1 billion
  annually) as 85 of its feedstock for ferrous
  castings
• U. S. Department of Energy (DOE), Office of
  Energy Efficiency and Renewable Energy (EERE),
  Industrial Technologies Program (ITP) Metal
  Casting Portfolio has funded research and
  development in cooperation with the metal casting
  industry to reduce its energy consumption and
  improve productivity

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Experimental technologies

• Electron Beam Melting
• Immersion Heater (High-Temperature Melting)
• Infrared Heating
• Microwave Melting
• Plasma Heating
• Solar Furnace

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Microwave Melting

• Originally developed by the DOEs Y-12 National
  Security Complex for melting of uranium
• Conventional heating involves transferring of
  heat through the outer surface of the material to
  the interior
• Microwaves can penetrate the mass, enabling rapid
  transfer of high-intensity heat throughout the
  bulk

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Microwave Melting

• Microwave melting could cut melting cost by 30
• Germany and Japan are taking a strong lead in the
  microwave technology applications

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Plasma Heating

• Plasmas are gaseous collections of electrically
  charged particles such as electrons and protons.
• As the ionized plasma flow hits the metal
  surface, it releases its energy melting the
  metal.
• The energy consumption rate is as low as 0.198
  kWh/lb (of aluminum) compared to 0.345 kWh/lb (of
  aluminum) in induction melting.

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Plasma Heating

• Minimizes metal loss due to oxidation and
  contamination
• Dross rate of melting aluminum is lowered to
  less than 1 compared to the conventional 3 to
  12.

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Coolant
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Introduction to cutting fluids and lubricants

• Cutting fluid used in the following operations
• Cutting
• Abrading
• Metal forming

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Introduction to cutting fluids and lubricants

• Benefits of metalworking fluids(coolants)
• Better surface finish
• Longer tool life
• Narrower tolerance of the work piece size
• Cleaner cutting zone
• Better resistance to corrosion

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Introduction to cutting fluids and lubricants

• Types of metalworking fluids
• Straight metalworking oils
• Emulsifiable metalworking oils
• Synthetic metalworking fluids
• Semi-synthetic metalworking fluids

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Facts about coolants

• 1984 figures
• Estimated 100 million gallons of metal working
  oil used per year in U.S
• Coolant consumption is estimated higher than 100
  million gallons per year
• Cost of purchasing and disposal is about 48
  billion a year.

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Health effects

• About 1 million workers are exposed to coolant in
  U.S
• Chlorinated paraffin transformed to dioxin
• Mist droplets can cause cancers, breathing
  problems and respiratory illness
• Non water miscible fluids usually cause skin
  disorders

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Health effects cont.
In addition
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Health effects cont.

• Bacteria and fungi can grow in cutting fluids
• Responsible for most of the health problems

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What is Dry Machining?
Dry Machining refers to machining with no fluids

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Motivation total manufacturing cost
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Motivation

• Disposal issues
• Permits
• Ecological compatibility

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Dry Machining Today

• Currently possible for some materials and
  operations

Milling Turning Drilling
Nickel Steel Aluminium
Decreasing Difficulty
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Cutting Fluids
Cool
Lubricate
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Dry Machining Options
Alternative Lubrication
Generate less heat
Alternative cooling
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Alternate Cooling

• Chilled air or Carbon dioxide
• Liquid Nitrogen

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Alternate Cooling Cold air gun
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Alternate Cooling Cold air gun
Valve
Vortex generation chamber
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Generate Less Heat

• Tool Geometry
• - Use of positive rake edges to reduce
  temperature
• - Chip grooves to break chips
• Process change
• - Higher speeds

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Generate less Heat Positive Rake edges
Positive rake with chip moving down top face of
tool bit
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Generate Less Heat
Inserts with positive rake edges
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- Chip groove to break chips into smaller sizes
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Alternative Lubrication

• Minimum quantity lubrication (MQL)
• Lubricious coatings

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Alternative Lubrication MQL

• MQL involves lubricating the workpiece with a
  very fine mist of coolant
• The coolants used are usually synthetic esters
  and fatty alcohols

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Alternative Lubrication MQL
Characteristic of Minimum Quantity Fluids
Fatty Alcohols -Long chained alcohols from
mineral oils -Poor lubrication
properties -Better heat removal due to
evaporation latent heat -Little residuals
Synthetic Esters -Chemically modified vegetable
oils -Biodegradable -Good lubrication
properties -Good corrosion resistance -Vaporises
with residuals
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Alternate Lubrication MQL
Typical MQL system
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Alternate LubricationLubricious coating

• Insulate tool from heat
• Lower friction for chip removal
• Coating usually achieved via Physical Vapor
  Deposition (PVD)
• Many possible coatings
• -TiAlN, TiCN, MoS2
• -combinations

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Other Processes

• Includes forming, joining and assembly, surface
  treatments, rapid prototyping and heat treating
• Concerns
• Increasing energy consumption
• Greenhouse gas emissions
• Must combined technical feasibility, cost
  effectiveness, ecological benefits

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Clean Process Design Process Modification-
Assembly

• Isolate processes identified as hazardous
• Eliminates direct hazards
• Auxiliary systems required
• Process Modification

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Green Assembly Plants

• Run out of easy fixes such as scrap
  elimination, energy efficient machines and
  solvent elimination
• Manufactures responsible for where and how they
  get the material- supply chains
• End-of-life management

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Application of solid lubricants-Turning

• Boric Acid- feasible alternative to the
  conventional cutting fluids
• Reduces cutting forces and tool wear
• low coefficient of friction at the tool work
  piece interface with the formation of lubricating
  film

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Feed System Boric Acid
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Government Incentives

• Renewable energy credits
• Tax incentives
• Energy Star

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Case Study Ford Motor Company and Pollution
Prevention
Dry Machining at Visteon Indianapolis Steering
Systems Plant
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Description of the Facility

• 1.9 million square foot facility in
  Indianapolis, Indiana.
• Operating since 1957
• Production of steering columns, gears, and
  automotive components.

Primary production operations
machining, heat treatment, and assembly of
components.
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Description of the Opportunity Being Addressed
Six thread grinding machines were being used to
produce power steering carbon steel worm gears.
These grinding machines required the use of
cutting oil. Oil mist emissions generated by
these machines required an air emissions permit
(potential emissions of 18 tons per year) and the
use of pollution control equipment.
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Description of the Improvement
Six grinding machines were replaced with five
whirl milling machines (no cutting oil.) The
quality of the finished part was significantly
improved to that produced by the old process.
Chips are removed via a drag belt chip conveyor.
Significant benefits of this improvement include
No oil mist No odor emissions No
requirement for pollution control equipment or an
air emissions permit No waste oil generation
75 less chip waste Chip waste is recyclable
Cutting tips are recyclable No sludges to be
landfilled No dermatitis risk Elimination of
fire protection requirements Plant recognition
- Governor's Award for P2
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Substance Addressed Reduction Obtained Cutting
oil 100 Oil mist emissions 100 Odors
100 Sludge 100
SAVINGS REALIZED (OPERATIONAL) 650,000 / YEAR
CAPITAL / OPERATIONS INVESTMENT 2.6 MILLION
PAYBACK 3.5 YEARS
ENVIRONMENTAL HIERARCHY LEVELS Source reduction
and waste stream elimination.
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Conclusion

• Manufacturing processes contributes to pollution
  and harms the environment.
• Existing processes and facilities must minimize
  flows and loads wherever possible, and nontoxic
  substances must be substituted for toxic
  substances wherever possible.
• Cleaner and more advanced processes that does
  less harm to the environment are available and to
  be discovered.

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Questions?