NEW TECHNOLOGIES TO REDUCE PRODUCTION COSTS
28 September 2006 - Boothroyd Dewhurst

Lean manufacturing
According to William Parr, professor in the Lean Enterprise System Design Institute and faculty director of the Greenwood Lean Enterprise Center at the University of Tennessee, lean manufacturing is a powerful tool that helps shops both large and small slash leadtimes and eliminate waste.

He says, "Most manufacturing processes are like riding on an airplane. Passengers usually are in the air moving toward their destination only about 20% to 25% of the time. Similarly, product is typically not moving toward getting ready for sale, it's waiting in a batch somewhere. With lean, companies reduce batch sizes, cutting the time parts are lying around waiting to be worked on. In fact, cutting leadtime by 1/2 is not unusual."

In the traditional manufacturing system, central planners send out memos that dictate which raw parts go where. They also send out work orders, describing what is to be built at the assembly and fabrication stations. Parr explains, "If the plan is perfect, with no variation, things are fine. What happens more often, though, is a lot of costly waste because there is always variation."

Lean, in contrast, operates using a "pull" system based on JIT delivery, in which parts are made and delivered only as needed.

Parr says, "Traditional push systems continue to grow inventory until shops go broke. Or until executives send out memos declaring an inventory-cutting binge for the next three months. I've seen this happen a lot in American industry. But pull systems inherently have low inventory because they put a bound on it."

Software that optimizes product design
Companies can slash costs by improving the design process at its beginning. Design for manufacturing and assembly software includes a design-formanufacture module, with which engineers obtain early cost estimates on parts or products, and a design-for-assembly module, which they employ to determine the best methods to manufacture products.

Engineers use the software where a design idea might still be scribbled on a napkin. Or, they use it to re-examine fully finished products to ensure design efficiency. For example, engineers take a part's geometry and determine whether the part should be made from a casting, or be machined, or injection-molded. During this process, the software draws from its large database, containing thousands of manufacturing processes, materials, and machinery, which was developed over many years in conjunction with companies such as GM and Ford.

Engineers also evaluate each assembly's function and the relationship between parts. They simplify and streamline designs repeatedly until achieving a minimum per/piece cost. For example, in one application, engineers slashed labor time by streamlining a product design to eliminate assembly screws.

Miles Parker, president of the Parker Group, Providence, R.I., says design houses can use software to design products efficiently and thus beat-out OEM design departments that may have more resources.

He says, "Too many companies outsource overseas based on comparative assembly rates, without looking at overall organizational costs. Companies doing innovative design and removing assembly labor don't have to go overseas to be competitive." He explains many Tier-ones and Tier-twos currently use the software but even small companies can compete if they make great designs.

In the past, design engineers designed a product and then gave it to the manufacturing engineers. Often, the product could not be manufactured easily or sometimes it couldn't be made at all. Parker continues, "DFMA solves these problems because designers use it in conjunction with service, quality, and production."

Smart machines
The Smart Machine Pilot Project is a collaborative R&D project run by the National Center for Manufacturing Sciences, Ann Arbor, Mich. The project helps the U.S. military depot system improve its productivity and reduce per/piece costs. One site, the Red River Army Depot, in Texarkana, Tex., needed help with outdated machinery that molds rubber onto the links for tracked vehicles. For one, the depots couldn't handle increased demand due to the war in Iraq.

During this project, engineers equipped facility machines with sensors and provided an electronic log to automatically capture data on each machine's performance and health. In the next phase, engineers will use this data to develop prognostics algorithms for a predictive maintenance system.

Project partners include the depots, NCMS, and several companies such as Advanced Technology Services Inc., Peoria, Ill., and Cincinnati Lamb, Hebron, Ky.

http://www.dfma.com

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