The April 1, 2008 issue of Theory and Practice from Manufacturing Insights had a great article on Design For X – the practice of incorporating different tangential factors into the design of a product that are intended to better integrate the new product with downstream activity. One of the more familiar DFX practices is, of course, DFM – Design For Manufacturing – where engineers strive to produce a product to be easier, safer and less costly to manufacture.
However, DFM is not the only DFX discipline that product companies need to consider. There is also DFSC – Design For Supply Chain, DFS – Design For Serviceability, DFC – Design For Compliance (& Sustainability), and DFW – Design For Warranty, and each of these is important. However, in today’s economy where costs are rising and discretionary spending is falling, probably the most important consideration in product design is the end cost of production. Since early interaction between design and supply chain is key to making the right build-versus-buy and material selection before design decisions, and associated costs, are locked in – I’d argue that DFSC should be on top of every company’s mind. Especially since, as the article points out, DFSC leads to further optimization and agility in the supply chain and reduces the impact of inevitable late changes and quality problems.
Of course, you cannot ignore DFS, DFC, and DFW. There are always going to be failures, and DFS evaluates design modularity and supply chain alternatives in order to maximize serviceability and enhance the customer ownership with inventory and reverse logistics operations in mind. A good design considers the complex dependencies between product design, reliability, service, inventory planning, and reverse logistics. The expected frequency of repairs and the type of parts that need to be replaced will determine the reverse logistics, depot repair, and part restocking requirements in the supply chain.
Similarly, if you actually want to be permitted to sell your products, you have to adhere to product compliance regulations such as RoHS and WEEE for the European electronics industry and the TREAD act for the American tire industry as well as corporate accounting regulations and overall social responsibility. Compliance cannot be an afterthought – it needs to be taken into account during design, manufacturing, shipment, servicing and decommissioning of products through a total life cycle approach. For example, in RoHS if even one separable component contains more than a minute trace of hazardous material, the entire assembly could be banned – leaving you with millions of dollars of inventory that cannot be sold.
Finally, you need to consider what reverse logistics and repair activities will exacerbate warranty costs and insure that tradeoffs are made to minimize those activities that will be most costly in the design process.
In short, DFX is a total lifecycle design practice that takes into account the costs and benefits of each and every design decision in the different life-cycle phases of a product, considering both the short and long term ramifications, from a Manufacturing, Supply Chain, Serviceability, Compliance, and Warranty viewpoint.