|
|
Engage product design in DFMA now; achieve lean savings of 30 to 50 percent later
For last month’s Lean Directions, Mike Shipulski, PhD, director of engineering for Hypertherm, a Hanover, N.H.-based, privately held company that designs and manufactures plasma-arc, metalcutting systems, co-authored an article with Mark Buck, Hypertherm’s vice president of manufacturing. The article, “‘Hyper’ for lean,” detailed the company’s lean journey and “low waste” product-design efforts. This month, Shipulski details the company’s lean product-design efforts as he issues a “call to action” for lean manufacturers everywhere to involve their product-design teams.
Why should the manufacturing engineering community care about engaging the product design community in pursuits such as design for manufacturing (DFM) and design for assembly (DFM)? The answer is simple—to make (and save) money.
What is DFM and how does it apply to lean? DFM is a methodology for changing a design to reduce parts count and the cost of manufacturing, while retaining product function. Fewer parts and lower costs make DFM a natural for lean efforts.
What is DFA and how does it apply to lean? DFA is a methodology for changing a design to reduce the cost of putting things together, while retaining product function. Fewer assembly steps, faster methods, etc., make DFA a natural for lean practices, just like its DFM counterpart.
Three important rules based on the working definitions are well worth noting: - Design for function first and hold onto functionality while practicing DFA and DFM methodologies.
- Product cost and product functionality must be considered together for DFA and/or DFM to be applied.
- The design must change or else DFA and DFM are not in effect.
When reviewing the rules, it is clear that the design community must lead the DFA/DFM efforts since product designers are the ones who establish functionality, change the design and design in the cost. The 30 to 50 percent cost reductions from DFA/DFM are achievable only when the design community leads the efforts.
Even with this understanding, there are few companies that allocate design-engineering resources to DFA and DFM. The reasons? The design engineers are booked at 150 percent utilization, the product development projects are late and there is risk associated with changing the design.
Usually companies run the DFM activities out of the manufacturing or purchasing functions and don’t even bother using DFA. Because manufacturing and purchasing don’t have the ability to change the design (see the third rule), the so-called DFM activities are really programs to take margin from suppliers by formally defining the costs of the suppliers’ processes, and negotiating even lower margins. The so-called DFM activities are not sustainable because the margins are finite; activities are not used company-wide because the suppliers eventually figure out what is really going on. These so-called DFM activities have given DFM a bad name and have made suppliers fearful of DFM programs, and rightly so.
Effective alternativeThere is a better way. The first and most important step is to educate company leadership in three important areas: the magnitude of savings from DFA and DFM (up to 50 percent), the leadership role of the design community and the importance of the DFMA management system to make it sustainable.
The second step is to tell the design community that success depends on them; that they are the only ones who can realize the significant savings from DFA and DFM, and that it is hard to design products with fewer parts and lower costs. The design community must look at the effort as a challenge that is difficult, but achievable, because of their unique talents. Last, the DFA and DFM tools must be married to a significant company challenge—either a product development project or an existing product requiring significant cost reduction.
If the savings from DFA and DFM are so significant, why aren’t more design resources allocated to DFA and DFM activities? One important reason is that design resources are overbooked. The excuse is that there is no time for DFA and DFM because “we’re too busy designing new products with costs that don’t meet targets, and we’re already allocating our time to follow-up on cost reduction programs.” Further, many think that DFA and DFM slow down projects, and that they don’t have time for longer projects. But DFA and DFM don’t slow down projects. The upfront work can take a little longer, but that time is more than made up for at the back end where work to improve producibility and product cost is eliminated. However, no one will believe that DFA and DFM don’t slow down projects until they have completed the first few projects.
Another reason for not allocating design resources is fear of unintentional changes to product functionality that could result from changing the product design. Companies don’t take on DFA and DFM projects that require significant design changes (and they don’t allocate design resources) because they are afraid their products won’t function properly after they are done and their customers won’t buy the products. To get over this fear, formalized validation of product function should be part of all DFA and DFM projects.
The last and real reason design resources aren’t allocated to DFA and DFM is that many companies simply do not believe that savings of 30 to 50 percent are possible. After years of struggling to reduce costs by 2 to 3 percent annually, it is difficult to imagine that savings of 30 to 50 percent are still possible. But 30 to 50 savings are possible by changing the design. The 2 to 3 percent cost reductions that companies are used to are largely made without changing the design and are made through factory efficiency improvements. Paradoxically, the sheer magnitude of the savings is what gets in the way. The savings are so large that no one can believe so much can be saved by allocating design resources. And because no one believes, no one tries.
The fact is savings of 30 to 50 percent are possible through enlightened use of DFA and DFM. So, I urge you to challenge your design community to use DFA and DFM methodologies. Savings of these magnitudes are possible if you are willing to do the hard work.
For more information about DFMA software, workshops, consulting services and international conferences, contact Boothroyd Dewhurst Inc., Wakefield, R.I.
 About the authorMike Shipulski, PhD, is director of engineering for Hypertherm, a Hanover, N.H.-based, privately held company that designs and manufactures plasma-arc metalcutting systems.
Copyright © 2010 Society of Manufacturing Engineers
SME Customer Service: 1-800-733-4763
|
|
|
|
 |
| November 9, 2007 Issue: |
|
|
