1. Environmentally Conscious Design & Manufacturing (ME592) Date: April 19, 2000 Slide:1 Environmentally Conscious Design & Manufacturing Class 19: Reuse Prof. S. M. Pandit

2. Environmentally Conscious Design & Manufacturing (ME592) Date: April 19, 2000 Slide:2 Agenda Needs and Benefits Elements Limits Implementation Evaluation Example

3. Environmentally Conscious Design & Manufacturing (ME592) Date: April 19, 2000 Slide:3 Reuse and Life Cycle Analysis

4. Environmentally Conscious Design & Manufacturing (ME592) Date: April 19, 2000 Slide:4 End-of-life Product Recovery Strategies Repair Refurbishing Remanufacturing Reuse of components Material recycling and disposal Energy recovery

5. Environmentally Conscious Design & Manufacturing (ME592) Date: April 19, 2000 Slide:5 Needs and Benefits - 1

6. Environmentally Conscious Design & Manufacturing (ME592) Date: April 19, 2000 Slide:6 Needs and Benefits - 2 Design for reusability (Technology) Better quality - ease of reuse Bookkeeping and control over effect of -Design -Materials -Manufacturing -Use

7. Environmentally Conscious Design & Manufacturing (ME592) Date: April 19, 2000 Slide:7 Needs and Benefits - 3 Costs are reduced because: Consistent guidelines are established for all mechanics When the part can and cannot be reused Forms the basis for a quality control program that lowers redo & warranty costs

8. Environmentally Conscious Design & Manufacturing (ME592) Date: April 19, 2000 Slide:8 Elements - 1 New Product Design Developing guidelines -e.g. small project:reusability limitations and salvage procedures for a shaft or a gear -e.g. Large project: reusability limitations and salvage procedures for all the piece parts in a family of components such as a turbocharger

9. Environmentally Conscious Design & Manufacturing (ME592) Date: April 19, 2000 Slide:9 Elements - 2 Defining the project -grouping Setting priorities -Costs of parts/ components -Field population -Wear or failure rate

10. Environmentally Conscious Design & Manufacturing (ME592) Date: April 19, 2000 Slide:10 Element - 3 Define reusable -Life? (80 % -100 %) -Used only on the same machine? -Risk of failure? -Fatigue life? Remaining failure is often impossible to determine

11. Environmentally Conscious Design & Manufacturing (ME592) Date: April 19, 2000 Slide:11 Limits Approximate reusable limits Salvaging options Second life probability -Laboratory tests -Field tests -Historical data

12. Environmentally Conscious Design & Manufacturing (ME592) Date: April 19, 2000 Slide:12 Implementation - 1 Measuring Inspection tools -Visual, transducers, machine optics Applications -severity factor

13. Environmentally Conscious Design & Manufacturing (ME592) Date: April 19, 2000 Slide:13 Implementation - 2 Failure analysis -Credibility of guidelines -Standardizing failure interpretation -Improves service quality -Sells more parts and service

14. Environmentally Conscious Design & Manufacturing (ME592) Date: April 19, 2000 Slide:14 Evaluation Maintain historical data on -Repair -Performance -Life -Failure modes and effects -Correlation with product batch

15. Environmentally Conscious Design & Manufacturing (ME592) Date: April 19, 2000 Slide:15 Example: Motor Reuse - 1 Today’s automobiles carry up to 100 electric motors There are two brushless and two stepping motors and one or two brushless fan motors in a laptop computer. It is estimated for an average North American household to have 60-80 electric motors, without accounting for automobiles. Source: Klausner et al., 1998, Journal of Industrial Ecology, 2(2), pp.89-102.

16. Environmentally Conscious Design & Manufacturing (ME592) Date: April 19, 2000 Slide:16 Example: Motor Reuse - 2 Commutator motors mainly consist of steel, copper, and plastics. These materials cannot be easily separated at end of life. Revenues of only some $22 per ton or $0.02 per motor (1998).

17. Environmentally Conscious Design & Manufacturing (ME592) Date: April 19, 2000 Slide:17 Example: Motor Reuse - 3 Reuse Potential Not compromise product quality Meet functional requirements of new motors Need a thorough understanding of used motors’ failure mechanisms and causes

18. Environmentally Conscious Design & Manufacturing (ME592) Date: April 19, 2000 Slide:18 Example: Motor Reuse - 4 Assessment of the Reuse Potential Need information on the degradation of the motors Approaches to assess reuse potential -Testing parameters after product return -Recording parameters during product use

19. Environmentally Conscious Design & Manufacturing (ME592) Date: April 19, 2000 Slide:19 Example: Motor Reuse - 5 Testing parameters after product return Requires the identification of parameters that indicates degree of degradation (e.g., noise, torque. Shortcoming: -Long time required for testing -High labor cost -Hard to identify the parameters that reliably shows the degree of degradation

20. Environmentally Conscious Design & Manufacturing (ME592) Date: April 19, 2000 Slide:20 Example: Motor Reuse - 6 Recording parameters during product use The temperature of certain spots on the motor The number of starts and stops of the motor The accumulated runtime of the motor The power consumption

21. Environmentally Conscious Design & Manufacturing (ME592) Date: April 19, 2000 Slide:21 Example: Motor Reuse - 7 Changes in Design Introduce one electronic data log (EDL), which records the history of the product’s usage and shows the degradation of the product when product is recovered. Design for disassembly to allow the old motor to be removed intact.

22. Environmentally Conscious Design & Manufacturing (ME592) Date: April 19, 2000 Slide:22 Example: Motor Reuse - 8 EDL records and analyzes the following data The number of starts and stops of the motor The accumulated runtime of the motor Motor temperature and the power consumption Peak and average values of all parameters of interest

23. Environmentally Conscious Design & Manufacturing (ME592) Date: April 19, 2000 Slide:23 Example: Motor Reuse - 9 Economic efficiency Additional cost incurred by EDL Return rate - Depends on consumers’ willing etc. Recovery rate - Determined by the return rate of old products and the yield in the product recovery stage

24. Environmentally Conscious Design & Manufacturing (ME592) Date: April 19, 2000 Slide:24 Big Picture - 1 Less resources used Resources diverted from waste stream Savings in cost

25. Environmentally Conscious Design & Manufacturing (ME592) Date: April 19, 2000 Slide:25 Big Picture - 2 -Setting up: -Classification -Clustering, group theory -Design for reuse -Tolerances, nominal dimensions, effect on performance -Failure mode and effects analysis