Limited Affordable Low-Volume Manufacturing Summary of a Workshop (2014) / Chapter Skim
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Summary of Workshop Presentations and Discussions
Summary of Workshop Presentations and Discussions
Pages 12-44
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From page 12... ...
He said that additive manufacturing was not the intended workshop focus, but it is an important, timely topic that is relevant to low-volume production. He also noted that low-volume production may also be relevant to sustainment,1 to produce low volumes of replacement parts.
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From page 13... ...
He said that while the economic conversation has recently focused on the idea of a replacement technology, it is not the appropriate way to frame additive manufacturing technology. Instead, his talk would focus on additive manufacturing as a disruptive technology, put into the context of economics and other forces at work.
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From page 14... ...
Dr. Jarboe then said the lesson from the railroad example is that a disruptive technology has two main characteristics: It allows for something new (not just
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From page 15... ...
He pointed out that additive manufacturing is a perfect example of a disruptive technology using this definition. First, additive manufacturing began as a technique for rapid prototyping, but it allows • Manufacturing new shapes that could not be manufactured before.
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From page 16... ...
During the question-and-answer period, a participant pointed out that there is a long way to go before additively manufactured parts are considered reliable and durable. Not only does additive manufacturing create more options geographically Dr.
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From page 17... ...
and continuing through to today's qualification of direct digital manufacturing (DDM) and its transition from rapid prototyping to low-volume production for the aerospace industry.
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From page 18... ...
Dr. Schafrik noted that a limited number of alloy powders are readily available from powder suppliers, although larger us ers need volumes sufficient to warrant the production of specialty powders.
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From page 19... ...
The speaker later added that advances in process models and process controls will enable precision shape control of the finished part without the need for finishing operations.
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From page 20... ...
For this to happen on a large scale, supplier capabilities must be improved. Some requirements are these: • Increase sophistication of additive process equipment; • Enhance capability to produce more complex shapes; • Modifiy current design practices to fully exploit DDM capabilities; • Replace castings with DDM; and • Reduce the time and cost to qualify the new process.
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From page 21... ...
Variable-rate production is key. Another participant asked if DDM could it be used for replacement parts for engines.
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From page 22... ...
However, the DOD may have to tolerate a heavy maintenance cost on top of the high original manufacturing cost, driven by parts that are not fully suitable for application in harsh environmental conditions or in specific circuit locations.
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From page 23... ...
Those parts having critical parameters that cannot be adequately controlled by vendor or military acquisition specifications are the ones for which a detailed, location-specific specification needs to be developed. Such a specification would ensure that the one or two parameters important for proper performance and reliability at a specific circuit location are controlled within limits that account for parametric drift due to aging and thermal effects over the design service life, using test sampling to verify performance.
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From page 24... ...
A well-controlled, closed-loop design process will not only prevent factory rework, cutting acquisition costs, but will also substantially reduce costs of ownership by reducing field failures. If a requirement is established for the OEM to determine the correct root causes of factory rework by identifying and gaining control of those key/critical parameters/characteristics missed in original design and development, field reliability will be improved and maintenance burden and costs driven down very early in the acquisition process.
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From page 25... ...
These design practices are commonly used for high-volume commercial and industrial electronics. The design tools already exist to perform variability sensitivity analysis necessary to minimize sensitive circuit locations and to identify, document, and provide a means of controlling critical parameters that can't otherwise be eliminated.
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From page 26... ...
REDUCING TOTAL LEAD TIME WITH QUICK RESPONSE MANUFACTURING Bill Ritchie, President, Tempus Institute Mr. Ritchie began his talk by describing his own history in the manufacturing industry and how production volume has varied through his career.
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From page 27... ...
Over head is usually 50 percent of total costs, while direct labor costs are 5 to 10 percent. He showed results from John Deere, looking at the relationships between total lead time reduction and cost for 12 of their projects.
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From page 28... ...
Ritchie said again that QRM is a strategy that introduces specific techniques to reduce total lead time, not just focusing on direct cost. He said that quick response manufacturing concepts apply throughout the enterprise, with most of the improvement in time savings in up-front office applications.
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From page 29... ...
Mr. Ritchie also said that total lead time could be the primary performance metric for all DOD manufacturing efforts.
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From page 30... ...
Johnson had said when asked that he did not think military acquisition policy should change, in reality some participants thought that is what his talk was recommending -- that the military should provide the specs. Another participant noted that a common point of discussion was the combi nation of low volume and high mix; the associated variety and lack of repetition are the big drivers.
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From page 31... ...
Dr. Gupta said that modeling and simulation can potentially benefit LVM through very large cost reductions, shorter design cycle times, improved efficiency, and enhanced performance.
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. They include integrated design and process models; tighter integration between design and process reduces the technology development cycle time.
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From page 33... ...
She suggested developing a shared resource that would bundle hardware, software packages, and technical talent. She singled out the Ohio Supercomputing Center9 as an example of this usage model.
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There is some trained expertise, but probably not enough, as the needs are substantial. A participant noted that high-performance computing and simulation were not sufficient; manufacturers need equipment to ultimately test models.
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From page 35... ...
Another participant noted that there are other shared access models worth examining. For instance, the Manufacturing Extension Partnership11 is a successful program in the manufacturing environment and has a presence in all 50 states.
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From page 36... ...
Dr. McGrath explained that the military acquisition spectrum tends to work at the two ends of the spectrum: purely military manufacturing or purely COTS.
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From page 37... ...
Dr. McGrath stated that the 2002 NRC report Equipping Tomorrow's Military Force contained five primary findings: • Defense system integrators have a pivotal role in integrated commercial and military manufacturing.
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From page 38... ...
McGrath referred to six primary recommenda tions of the 2002 NRC report: • Implement policies, incentives, and guidelines for integrating commercial and military manufacturing. • Contract for life-support and technology refreshment.
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From page 39... ...
A traditional defense supplier was selected as the systems integrator, however, and no EMS companies were part of the program. The lesson learned was that use of commercial suppliers needs to be considered by the defense prime during systems engineering.
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From page 40... ...
Schneider responded that Key Tech has been unable to find a company willing to do this on a commercial scale. Another participant noted that the Army's Edgewood Chemical Biological Center is using metal laser sintering technology to create mold inserts for injection-molded parts.
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From page 41... ...
Another participant asked what Key Tech gives to the manufacturer for production -- whether it is an entire digital data set or something else -- and how easy it is for the manufacturer to move forward with that information package.
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From page 42... ...
Dr. Latiff also asked if Key Tech had made use of any manufacturing hubs such as fab labs or makerspaces.
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From page 43... ...
He was asked if Key Tech has government clients, and he said not directly, but that Key Tech has subcontracted with other companies for biodefense/aerosol pathogen detection products for government agencies. A DOD participant noted that industry seems to be moving away from using annotated 2D drawings or even 3D renderings and instead is using the part itself.
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From page 44... ...
For alternative manufacturing to be a viable business model, a value case must be made for it. One participant noted that there are many ways to make low-volume produc tion easier, such as using advanced data packages and simulations.
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