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Designing Products for Extended Life Spans and Multiple Profit Cycles – Remanufacture and Reuse

Designing Products for Extended Life Spans and Multiple Profit Cycles – Remanufacture and Reuse. A Product’s Life Cycle – From Cradle. Basic questions you need to ask and keep in mind when designing: What do we want to do, why, and how?.

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Designing Products for Extended Life Spans and Multiple Profit Cycles – Remanufacture and Reuse

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  1. Designing Products for Extended Life Spans and Multiple Profit Cycles–Remanufacture and Reuse

  2. A Product’s Life Cycle – From Cradle • Basic questions you need to ask and keep in mind when designing: What do we want to do, why, and how? The phrase “demanufacture” is used to characterize the process opposite to manufacturing involved in recycling materials and products.

  3. Recycle and Re-Use – AAMA Definitions • Recycle: • A series of activities, including collection, separation, and processing, by which products or other materials are recovered from or otherwise diverted from the solid waste stream for use in the form of raw materials in the manufacture of new products. • Materials which are diverted for use as an energy source should be documented separately under the category of energy recovery • Re-Use: • The series of activities, including collection, separation, and in some cases processing, by which products are recovered from the waste stream for use in their original intended manner. • Remanufactured components fall under the classification of re-use. • (Germans refer to this as “product recycling”.) • Note: Both definitions include collection as a first step. • Reverse logistics and reverse logistics management (RLM) are a (design) concern.

  4. Reverse Logistics Management

  5. What is the Objective of RLM? • What is the RLM for? • Product service for customer/owner? • Product reuse “as-is” for new customer? • Product remanufacture for new customer(s)? • Recycling of product’s material? • Disposal of product? • Or all of the above for selected sub-assemblies of the product? • Other? • The RLM intent will drive to a large extent the “design for RLM” effort. • Material recycling allows for destruction of the product. The issue of transport damage is almost irrelevant. Design for Disassembly requirements for mechanical separation are different that for manual separation. • Product reuse/remanufacture relies on a high residual value. Transport damage is to be avoided or limited by proper logistics product and logistics design.

  6. Who is doing the RLM and Life Extension? • Who is driving/controlling the RLM? • The Original Equipment Manufacturer (OEM)? • A third party contracted by the OEM? • An independent friendly or “hostile” entrepreneur • Associated big issue: who “controls” the product design and what influence do life-cycle participants have over the design? • One of the most critical issues for independent remanufacturer is how and where to get the replacement parts.

  7. Automotive Cores at Independent Remanufacturer

  8. Delta Airlines

  9. Designing Products for Remanufacture & Re-Use

  10. Product Life Extension • Products become obsolete because of • technical obsolescence • fashion obsolescence • degrade performance or structural fatigue caused ny normal wear over repeated uses • environmental or chemical degradation • damage caused by accident or inappropriate use • To achieve life-extension and multiple profit cycles, these issues have to be countered. • Critical Issue: The “openness” of the product design strongly affects RLM and associated life extension processes • Upgradable products allow for a larger percentage to be salvaged • Use of technology that is proprietary or difficult to reverse engineer will block/limit the number of independent entrepreneurs

  11. Characteristics of Flexible Product Platforms Flexibility of product platforms can be enhanced by improving any of the following core characteristics: • Modularity: • relationship between a product’s functional and physical structures such that there is (1) a one-to-one correspondence between functional and physical structures, and (2) a minimization of unintended interactions between modules • Robustness: • capability of system to function properly despite small environmental changes or noise • Mutability: • capability of system to be contorted or reshaped in response to changing requirements or environmental conditions

  12. Design Parameters • Assumptions: • We want to increase and not block product reuse/remanufacture/recycling. • We are open to others becoming involved. • “Big” issues (organizational design): • Infuse life-cycle thinking in the design and product realization teams. “Traditional” designs were at best designed with serviceability in mind. • Get (if possible) life-cycle partners about the quality of your product and how to improve his/her life. • Make sure your suppliers participate as well. • “Small” issues (hardware design) • Life-time extension through durable design. • Life-time extension of product “core” through modular and open design. • Recyclability improvements through proper material selection. • Remanufacturability improvements through proper fastener selection. • Etc. (see common available literature)

  13. Do Not Forget UNCERTAINTY! • In remanufacture, recycling, etc., the number and range of uncertainties are higher than for “regular” manufacture and logistics because many of the concerns are out of the control of the OEM and the designers. • Product uncertainties: • How long is its life? • What is its state after its life? • What changes have been made during its life? • Etc. • This affects organizational uncertainties such as: • How many will be available for take-back? • How long will it take to reprocess the product? • Etc. • Designers and product realization teams should at least be aware of uncertainties, but also try to manage the uncertainties by smart product and process design.

  14. Design Guideline Examples – Optimization of Initial Life-Time • Reliability and durability • If something breaks, it can become waste immediately • Easy maintenance and repair • Especially for energy and material intensive products this should be pursued • Modular product structure • Allow for upgrading of function. • Open systems. • Modern computers are a good example. • Classic design • Porsche 911s and MGBs are being restored and well kept. A Yugo is not. • Aesthetically appealing and “time-less” designs are usually better maintained • User taking care of product • Proper care and maintenance by user can significantly extend a product’s life-time. • User typically does take care of capital intensive products (e.g., a car), but what about a relatively cheap product (e.g., a $10 alarm clock).

  15. Know Your Life-Cycle Processes! • Know what process you are designing for! • E.g., there is a clear distinction between manual vs mechanical separation design guidelines when it comes to fastener selection. • Manual Separation: • Reduce number of fasteners, commonize fastener types, use fasteners made of same or compatible materials, consider snap-fits (two-way, if necessary), etc. • Consider destructive fastener removal (possible inclusion of break points) • Mechanical separation (destructive): Fasteners will not be unfastened and fastener disassembly time is irrelevant! • Material properties are key issue! • In order of preference, use 1) Molded-in fasteners (same material) 2) Separate fasteners of same or compatible material 3) Metal fasteners (easy to remove due to magnetic properties) • Plastics should have at least 0.03 density difference for sink-float separation) Integrated Product and Process Design should be pursued.

  16. Remanufacture Process and Issues

  17. Basic Processes • Disassembly is not the only process in remanufacture or recycling. • For remanufacture and re-use, the following processes are typically considered: • disassembly (non-destructive), • cleaning, • inspection and sorting, • part upgrading or renewal, • re-assembly. • For material recycling: • material separation (disassembly), • sorting, • reprocessing.

  18. Listen to Practitioners ! Hammond, R., Amezquita, T. and Bras, B., 1997, “Issues in the Automotive Parts Remanufacturing Industry – A Discussion of Results from Surveys Performed Among Remanufacturers,” Journal of Engineering Design and Automation, Special Issue on Environmentally Conscious Design and Manufacturing, (in press).

  19. Most Costly Operations

  20. Disassembly Difficulties

  21. Cleaning Difficulties

  22. Inspection Difficulties

  23. Refurbishing Difficulties

  24. Reassembly Difficulties

  25. Key Decision Criteria

  26. Design Issues

  27. Changes in the Remanufacturing Industry

  28. Some Observations • Availability and cost of replacement parts are dominating factors. The increasing product diversity and part proliferation are adversely affecting this. • Light-weighting was also identified as a negative (OEM) design change. So are the increase Design for Assembly efforts which emphasize part integration and one-way fastener connections. • Cleaning and associated regulatory issues was identified as one of the highest cost contributors. • Corrosion was ranked highest in complicating the disassembly process. • Employee skill is an issue predominant in three categories. • The margin of profitability needed to consider a product for remanufacture ranges between 30 - 100 %. However, key (and blocking) issues are part proliferation and lack of replacement parts.

  29. Typical Process Problems • Facility level: • Core pipeline is too long • Large core and finished good warehouses • Inadequate supply of replacement parts & cores • Finished goods warehouse has priority over production • Mass production mindset • Process and Operations level: • Setups are too long • Cycle times of batch operations are too long • Batching generated delays - long lead times • Job shop layout • Craft production practices • Cores & component parts are damaged during processing • Parts are cannibalized • Clearly, one should not forget PROCESS DESIGN!

  30. Craft and Mass Production Examples • Enough cores have to be collected before the machine can (economicaly) operate • Human errors can ruin cores.

  31. Typical Material Flow for Current Remanufacture Operations

  32. Lean Remanufacture Material Flow • Amezquita, T., 1996, "Lean Remanufacturing in the Automotive Industry," Master of Science Thesis, G.W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia. • Amezquita, T. and Bras, B. A., 1996, "Lean Remanufacture of an Automobile Clutch," First International Workshop on Reuse, Eindhoven, The Netherlands, pp. 35-52.

  33. Moving to Lean Remanufacture • Obtaining Economies of Scale and the Ability to Handle Large Varieties of Products • Eliminating non-value added resources and activities • Integration of production system elements and work functions

  34. Design for Remanufacturing Guidelines–Attention to Details

  35. Disassembly, Cleaning, and Inspection • Ease of disassembly: If disassembly cannot be bypassed, make it easier so that less time can be spent during this non-value-added phase. • Permanent fastening such as welding or crimping should not be used if the product is intended for remanufacture. • Also, it is important that no part be damaged by the removal of another. • Ease of cleaning: Parts which have seen use inevitably need to be cleaned. In order to design parts such that they may easily be cleaned, the designer must know what cleaning methods may be used, and design the parts such that the surfaces to be cleaned are accessible, and will not collect residue from cleaning (detergents, abrasives, ash, etc...). • Ease of inspection: As with disassembly, inspection is an important, yet a non-value-added phase. The time which must be spent on this phase should be minimized.

  36. Sorting and Inspection Inspectability: • Make failures easy to detect. Sorting: • Make parts easy to detect and facilitate standard and automated handling procedure. • Reduce amount of sorting by reducing component count. Standardize fasteners on either length or thickness

  37. Cleanability • Minimize geometric features that trap contaminants. • A sharp concave corner is an example of a geometric feature which traps contaminants • If a rib or plate is expected to trap dirt or grease, consider making it removable (see figure). • Reduce contamination through wear. • Reduce corrosion and wear if part is to be re-usable. Make difficult to clean spots, corners, and traps removable

  38. Component Replacement, Reassembly, and Reuse • Ease of part replacement: It is important that parts that wear are capable of being replaced easily, not just to minimize the time required to reassemble the product, but to prevent damage during part insertion. • Ease of reassembly: As with the previous criteria, time spent on reassembly should be minimized using Design For Assembly guidelines. • Where remanufactured product is assembled more than once, this is very important. • Tolerances also relate to reassembly issues • Reusable components: As more parts in a product can be reused, it becomes more cost effective to remanufacture the product (especially if these parts are costly to replace).

  39. Modularization and Standardization • Modular components: By making designs modular, the assembly and disassembly times can be reduced which enhances remanufacturing. • Standardization: Standardization always supports remanufacture. Pay special attention to the following: • Components: Use as much as possible standard, commonly and easily available components. Use of specialty components may render remanufacture of assemblies impossible if these specialty components cannot be ontained any more. • Fasteners: By standardizing the fasteners to be used in parts, the number of different fasteners can be reduced, thus reducing the complexity of assembly and disassembly, as well as the material handling processes. • Interfaces: By standardizing the interfaces of components, a fewer of parts are needed to produce a large variety of similar products. This helps to build economies of scale which also improves remanufacturability. • Tools: Ensure that the part can be remanufactured using commonly available tools. The use of specialty tools can also degrade serviceability.

  40. Upgrade / Renewal and Re-assembly Build in (material) redundancy for refurbishing/upgrading/partial replacement Allow for replacement of studs and other fasteners • Allow for easy re-assembly. • Follow Design for Servicability guidelines.

  41. A Case Study Example

  42. Investigative Case Study: Automobile Door • Let’s investigate a product which is not currently remanufactured. • Purpose: • Identify characteristics which would facilitate cost-effective remanufacture of the product. • Exercise existing design for recycling and remanufacture guidelines • Identify potential design changes to enhance remanufacturability • Specific tasks: • Assess current design and the repair process - look at costs. • Develop design criteria which would make the door more remanufacturable. • Develop alternative designs for door components. • Develop a remanufacture process. • See if there is an economic viability.

  43. Current Door Design and Repair Process • Designing for Remanufacturability • Part of the trade-off process in design • Had been sacrificed in favor of higher priority goals • Remanufacturing is becoming more important • Economics • New door cost between $1,000 and $2,000. • Salvaged door (before remanufacture) cost between $100 and $400 • Repairing Damaged Doors • Comparison: Chrysler $430 Buick $388 Saturn $143 • Why are Saturn’s doors so much less expensive? Door skin is easily removed - requires less time and simplifies removal of interior components of door Major Cost Driver Door Skin Replacement ~ 10 Hours Per Door!

  44. Design for Remanufacture Criteria(Demands and Wishes) 1. Materials W All materials must be recyclable W No substantial increase in cost of materials D Must be corrosion resistant D Must be durable D Easily refurbishable W Light weight W Environmentally benign processing methods D Robust enough to reuse without replacement W Use recycled materials D Avoid toxic materials D Use secondary finishes such as painting, coating, etc. W Keep secondary finishes clear 2. Assembly methods W Less complex than existing methods W Faster than existing methods W Common method for diverse styles D Use Design for Assembly methods W Reduce number of components 3. Fasteners D Must be corrosion resistant D Must be durable D Must be reusable D Do not use screw heads which are easily damaged (e.g., Torx, Phillips, etc.) W Do not combine metric and standard screws D Use standard fasteners 4. Design for Separability D Choose joints that are easy to disassemble D Simplify and standardize component fits W Identify separation joints W Make adhesives safely soluble W Layout plastic parts close to top level of disassembly path D Provide "easy to see access" for disassembly D Provide access for power tool operation 5. Cleaning D Easy to handle and clean components W Do not use grooves or cavities that are hard to clean 6. Parts Replacing D Make parts susceptible to breakage easy to replace W Make parts susceptible to breakage separate from other parts 7. Modular components D Standard interfaces D Commonization/standardization of parts 8. Design for Recovery D Parts must be high quality and durable W Parts must be easy to remove but not to steal (See Amezquita, T., Hammond, R. and Bras, B., 1995, "Characterizing the Remanufacturability of Engineering Systems," 1995 ASME Advances in Design Automation Conference, DE-Vol. 82, Boston, Massachusetts, ASME, pp. 271-278)

  45. Current Design

  46. Design Concepts for Enhanced Remanufacturability Door Skin Attachment Method From Crimped to a Tonge & Groove/Screw Assembly Window Frame Plastic Trim Replace screws with Tongue and Groove Assembly Window Trim Moldings Remove Molding - Single Window Opening Window Mechanism Fasteners Change Fasteners From Screws to Rivets

  47. Hypothetical Automobile Door Remanufacturing Facility • An investigation of the economic feasibility of large scale automobile door remanufacture was also undertaken. Approach: • design an actual business, and • perform subsequent economic analyses. • Economic base line: • Actual prices for a specific car door were taken from Mitchell’s 1994 Collision Estimating Guide, Domestic. The price for a totally new door is $1,177 before labor costs • According to Lund & Skeels (1983), the price at which remanufactured automotive components can competitively sell for is 57% of the new item price • Thus, the estimated price the market will bear is $671 for this particular door. Potential physical layout of specialized door remanufacture facility.

  48. Process Assumptions The following assumptions were made: • Test Market: Metropolitan Atlanta with 429 body shops in test area. • Half of the body shops will want remanufactured doors. This is based on the fact that new cars (<2 years old) might receive new doors, whereas the older cars won’t. • Each shop will require one door per week. Assumed volume: 215 doors per week. • Cores will be available and subsequently purchased through salvage yard network. • Process will be Just In Time (i.e. doors will be purchased and processed as orders are received). • The end product is a primed door casing (shell and skin) with associated components packaged and delivered with the shell. No other assemblies attached. • Parts which are remanufacturable (from a standard list) will be, and they will accompany the door to the purchaser. • The purchaser will be responsible for obtaining nonremanufacturable parts (from a standard list) and final painting/assembly of the door. The justification for this is that each door will require a specific color more readily matched on site. Further, painting an entire door (like new) requires parts to be off during painting. Currently body shops receive parts independently and are able to paint the door frame (shell + skin) without the parts attached. Therefore, this proposed procedure is consistent with current operations. This practice assures like-new condition of the car door. Shortcoming: this is a labor intensive process for the body shop in reassembly. • Based on a 32 minute disassembly time (based on experimental time studies on donated doors), and 7 hours of labor time during a day, only 14 cars may be disassembled by a person per day. This means at least 4 people are required to disassemble the required doors. However, improvements in production (e.g. training, experience) reduce the labor force to 3 for disassembly. • Capital Investment is not considered - only steady state operational costs. • Warranty returns: 1-2%. Ex: door shell, parts don’t fit, etc.

  49. Economic Assessment • An Activity-Based Costing model was developed and implemented in MS Excel to obtain an economic assessment. • Uncertainties in the assumptions, cost drivers, and consumption intensities were included using the Crystal Ball software, resulting in the cost distribution below. • Approx. 80% of the forecasted situations is less than $671, the maximum allowable cost to make remanufacture an option.

  50. The Human Factor – Overloading the Designer Common “complaint” : “I have to satisfy my customer demands, my boss, get the product out on time, meet all the deadlines, do DFMA, TQM, etc., and now I also have to worry about DESIGN FOR REMANUFACTURE?” (a.k.a. the swamped engineer syndrome

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