Design for Cost and Environment

Question 1

What are the current environmental problems we are facing?

Answer 1

• Global warming.
• Pollution (air, light, noise, water, etc.).
• Habitat destruction.
• Resource depletion.

Question 2

List the difficulties of environmental impact analysis.

Answer 2

• Difficult to get accurate energy and cost data for material production.
• Difficult to account for building of infrastructure.
• Many types of material.
• Quantities of recycled material can quickly change.
• Energy prices can change rapidly.

Question 3

Who are the stakeholders of projects?

Answer 3

• Engineers
• Professional bodies
• Governments
• Businesses
• Public

Question 4

What is the ISO 14001?

Answer 4

Internationally recognised framework for setting up an Environmental Management System (EMS).

Question 5

What are some benefits of the ISO 14001 framework?

Answer 5

• Identify cost savings in resource, waste and energy management.
• Improve efficiency/reduce impact.
• Improve corporate image and credibility.
• Quantify, monitor and control the impact of your operations.

Question 6

What are the three typical design objectives in material selection?

Answer 6

Minimise mass, cost and energy.

Question 7

List the material indexes for stiffness (unconstrained) and stiffness (constrained).

Answer 7

Mass: E^(0.5)/p and E/p

Cost: E^(0.5)/pc and E/pc

Energy: E^(0.5)/pe and E/pe

Question 8

List the material indexes for strength (unconstrained) and strength (constrained).

Answer 8

Mass: Sigma^(2/3)/p and Sigma/p

Cost: Sigma^(2/3)/pc and Sigma/pc

Energy: Sigma^(2/3)/pe and Sigma/pe

Question 9

List the material indexes for mechanical energy absorption.

Answer 9

Mass: (Sigma)(Epsilon)/p

Cost: (Sigma)(Epsilon)/pc

Energy: (Sigma)(Epsilon)/pe

Question 10

List the material indexes for mechanical energy storage.

Answer 10

Mass: Sigma^2/pE

Cost: Sigma^2/pEc

Energy Sigma^2/pEe

Question 11

List the material indexes for thermal conductivity (equal lambda/t)

Answer 11

Mass: Lambda/p

Cost: Lambda/pc

Energy: Lambda/pe

Question 12

List the material indexes for thermal insulation (equal lambda/t)

Answer 12

Mass: 1/(Lambda)p

Cost: 1/(Lambda)pc

Energy: 1/(Lambda)pe

Question 13

List the types of repair.

Answer 13

Remake - OEM makes a brand new sub-assembly as a new part.

Remanufacture - OEM disassembles and reassembles system from a combination of reconditioned and new elements.

Recondition - 3rd party salvages sub-systems and reconditions them with limited testing and warranty.

Reuse - Customer buys second hand part from scrap yard or recycling company.

Repair - Faulty sub-system is taken apart and the fault is identified and then repaired.

Question 14

List the guidelines for aiding recycling.

Answer 14

• Avoid using more materials than is necessary.
• Make parts easier to disassemble.
• Use material identifiers.

Question 15

List the guidelines for reducing energy footprint.

Answer 15

Cars: Do not use cars for short journeys, use trains for longer journeys, drive a car no bigger than it needs to be, live closer to work, drive higher efficiency cars.

Air Travel: Have more holidays in the UK, add holidays to the end of business trips, use video conferencing, have holidays in Europe.

Home: Do not heat more rooms than necessary, insulate the house, use LEDs, collect rain water, don’t wash/dry clothes more than necessary.

Clothes: Use them for longer and recycle them.

Foot: Eat less imported food, less high energy foods, less waste, don’t overeat.

Electronics: Use for longer and recycle them.