A design for end of life
Ever-increasing regulation and new thinking about end of life are putting pressures on design. Tom Shelley reports on the different approaches to these problems.
Once, it was acceptable just to design a product to work well and not to worry about what became of it at the end of its life cycle. Today, however, engineering companies have to worry about what happens to their goods once their purchasers have completely finished with them.
Pressures come from government, customers, the public and that most fundamental need: to maximise profit. Equally, there is the question of which method of end-of-life recovery represents best practice from both a financial and an environmental point of few. Needless to say, this has placed an additional burden on engineering designers.
Regulations relating to end of life (EoL) recovery that have to be conformed to in Europe include: REACH (Registration, Evaluation and Authorisation of Chemicals), RoHS (Restriction on the use of Hazardous Substances) in electrical and electronic equipment, ELV (End of Life Vehicles), WEEE (Waste Electrical and Electronic Equipment) and EuP (Energy using Products). As if this weren't enough, for those who trade internationally, there is also GADSL (Global Automotive Declarable Substance List), a list of special requirements imposed by the State of California, JIG (Joint Industry Guide), and additional requirements imposed by individual countries.
Obscuring the issue
Unsurprisingly, these myriad regulations have tended to obscure rather than illuminate the issue. For instance, when asked by Eureka if he found the various European Union regulations to be subject to different interpretations in different European member states, one automotive engineer said: "Two engineers sitting next to each other often don't manage to agree on what the regulations mean."
Software is already helping with one of the most basic problems; namely the materials that are used in the products themselves. 'Insight' is the latest form of a product originally called EMARS (Environmental Material Aggregation and Reporting System) which comes from Synapsis Technology. John Fox, director, product and market strategy, told a recent PTC seminar that it originated from work with Motorola, but is now being aimed at the automotive and aerospace sectors.
InSight includes patented technology to undertake Bill of Material (BOM) aggregation as well as a system for asking suppliers exactly what is in the parts they are supplying and logging whether their answers conform to regulations or whether they have given either partial or no replies. Graphical icons show up problems with components, possible problems if regulations change and applications where some parts can be used, but not others.
When asked if Insight could be tailored for SMEs, however, Fox responded: "Our customer base generally consists of manufacturers who have complex products and supply chains. For these, it's very difficult and costly to track restricted substances, suppliers and analyse products to ensure compliance.
Smaller companies tend to have simpler products and few suppliers so have less of a need for automation." That said, small companies can make use of mainstream commercial CAD software by linking design data to information about regulatory requirements in PDM and PLM systems.
Assuming products are properly composed in the first place, however, the question arises of what can be done at the other end of the process to make the best use of them. Should they be crushed or shredded for recovery of materials? Or designed so that parts can be carefully recovered so that they can be remanufactured and sold again? Or should they be made repairable and upgradable and put back into service?
Getting maximum value
The traditional end of life treatments, of course, have tended to involve the crushing and/or shredding of products for recycling. However, this can result in low-value recyclate streams and does not extract the maximum value from EoL products. This means that the designing of goods for re-use or remanufacturing an increasingly attractive proposition for reasons that are both environmentally and financially sound.
Of course, the automotive manufacturing industries and their Tier 1 suppliers have long been in the habit of reconditioning their components for re-use. Long before they were required to re-use or recycle, they found it made good sense to take back worn units, refurbish them and then sell them back to customers. Aircraft engines have always been designed to be stripped, overhauled and rebuilt, as have most major items of defence and railway equipment. Equally, Xerox has long used remanufacture as a means of creating ongoing revenue streams.
Nonetheless, specifically designing products for remanufacture is a relatively new concept as far as most manufacturers are concerned. A remanufacturing system collects EoL products, returns them to their original condition then retails them at an as-new price. Importantly, remanufacture results in the extension of a product's life and promotes the re-use of components and materials. It is a means of generating (even potentially doubling) profits, preventing waste and conserving natural resources.
Remanufacturing is currently worth approximately £2.5billion in the UK, but design for remanufacture itself remains little practised. This, according to Caspar Gray, co-director of design consultancy Wax RDC is due to a 'widespread lack of OEM engagement in the process and designers' lack of awareness of eco-design, let alone design for remanufacture'.
Wax RDC specialises in design for remanufacture and recycling. Indeed, it encourages its OEM partners to take advantage of the business model of remanufacture and incorporates redesign for remanufacture into its design process. Examples of Wax's work include Meo, a handset designed for Mioteq which incorporates a new business model with a two-tier lease system.
Discussing the processes required for successful design for remanufacture, Wax's co-founder and director Damien Jones explains: "There are three things you have to do: make sure you can get the product back; make sure you can take it apart cost effectively; and make sure there is a market for the product once it has been remanufactured. All of these can be influenced by design, using life cycle thinking. Research and benchmarking of current, competitive products is essential."
Critically, whether a product is to be remanufactured, reconditioned, or recycled in a way that does not involve shredding, it has to be taken apart. One idea to assist this that once looked very promising, but seems for the moment to have gone out of fashion is 'Active Disassembly', which was originally invented by Dr Joseph Chiodo of Brunel University. The idea behind active disassembly is to use fasteners that either change their shape or decompose when they are heated. Thus, that when the product is heated for one minute in hot liquid at 117ºC or 14s at 165ºC, it falls apart. Shape change can be achieved by using shape memory alloys or shape memory polymers.
However, David Parker, head of remanufacturing at the Centre for Remanufacturing and Reuse, says of active disassembly: "There's been a lot of talk, but not a huge amount done." Much of the research was undertaken with regard to Nokia mobile phones. But Parker says current legislation provides neither stick nor carrot. "Why would Nokia want to do it? If it's somebody else who does the remanufacturing or recycling, what's in it for Nokia? For Nokia, it is added cost and the company is very cost driven. The problem is open supply chains: if the products go back to the original supplier, then it is worth designing them for disassembly. Otherwise, it isn't." When it is, Parker says products need to be designed to be deconstructed with minimum damage.
Going further on this subject, Wax RDC's Jones says: "Design for disassembly is a complex process, but the basic guidelines are: reduce the number of parts in the product; reduce the total number of fasteners used; reduce the number of different fasteners used; reduce the number of different materials used (especially plastics); reduce the number of assembly axes; eliminate adhesives; and use active disassembly components where appropriate."
To this end, it is worth noting that there have been a number of recent developments in fastening that may assist active disassembly. One is a novel patented fastener that locks up firmly to resist vibration without requiring the dab of threadlocker that makes them subsequently hard or, in some cases, impossible to undo. Developed in the US, 'asymmetric fasteners' have a thread with a shallow incline on one side and a steep incline on the other. The wedging action between the shallow thread incline on the nut and bolt or sleeve allows free rotation until resistance is encountered. An additional turn then wedges the parts into a locked and vibration-resistant condition.
Unfortunately, of course, there will always be products that cannot be remanufactured or re-used. This may either be because it is not cost effective to do this, or possibly because rapid technical progress means that nobody wants last year's model. Since companies are increasingly being required to offer to take their products back, however, there is still considerable benefit to be derived from designing such items to be recycled as parts.
In this event, Jones' guidelines become: "Reduce the number of different materials used (especially plastics); if more than one plastic is used, make sure they have different densities; label all plastics with their type in standard form; use finishes compatible with the materials; build in value for the recycler so that it is worth recycling; eliminate adhesives and avoid snap fits, unless made of smart materials; and label the product with recycling symbols."
Increasingly stringent legislation placing responsibility for products squarely at the door of their producers is undoubtedly making the consideration of EOL treatment a priority for designers, manufacturers, recyclers and governments. However, it seems possible that, with the right approach, it could prove to be as much benefit as burden.
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