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Integrated Simulation Delivered

April 21, 2008
Two complementary technologies have been tightly integrated into a single product by Simufact, enabling end-to-end simulation of manufacturing processes.
Early last year a remarkable simulation software program became available, called Simufact.forming. It is the first program that offers a fully integrated solution to virtually every manufacturing problem imaginable in the metal forming industry, using the two well-known solution methods: the Finite Element Method and the Finite Volume Method. The software is based on the merger of two separate, long-established programs, MSC.SuperForm and MSC.SuperForge, which at the end of 2006 were divested by MSC.Software.

The timing of this development could not have been better for forgers, because it is becoming increasingly critical for those operations to be near perfect in all categories — quotation time and accuracy; manufacturing costs, on-time delivery, and quality.

According to Aberdeen Group research, implementing manufacturing process simulation is a critical step toward becoming a best-in-class forging company that can compete in the global economy, where price pressures, off-shoring, rapidly changing customer requirements and design complexity are among the top pressures on every forging shop.

The complete integration into a single, powerful application, yet one that is intuitive and easy to use, is a milestone in the field of manufacturing process simulation. There is a considerable level of anticipation that this software will change the present state of manufacturing simulation. If so, much of the credit will go to Dr. Hendrik Schafstall and his development staff at Simufact Engineering (www.simufact.de/en/).

Laying the foundation As chief technology architect for the company, which is headquartered in Hamburg, Germany, Schafstall spent the past 13 years laying the foundation for this product. In the 1990s, as he conducted doctoral research on the topic of “Friction Modeling in Bulk Metal Forming Simulation,” Schafstall realized the power of the finite-element method. In 1995, together with Michael Wohlmuth, he established a company dedicated to simulating manufacturing processes. Since then, they have collected an impressive array of customers, small and large, who have benefited from their expertise and the unique technologies offered.

Typical examples of simulations using the finite-element approach are hot and cold forging, tool and die stress analysis, and rolling and reducing.

One benefit gained from these simulations is the early detection of flaws in the process, like die under-fill and creation of cracks, folds, and laps. It also allows evaluation of the die-loads and the stresses that are developed inside the dies, and determination of the residual stresses in the part after forming.

A unique feature of Simufact.forming is not only that it accounts for the plasticity of the material behavior, but it also incorporates information on the elastic deformations and corresponding stresses. This provides an accurate calculation of the pressure that is applied to the tools, and it also provides an accurate calculation of the residual stresses in the final part after removal from the press.

This insight allows optimization of material usage, avoids expensive trial-and-error runs on the production line, makes it possible to significantly increase tool life, and allows the designer/developer to make estimates about the service life of the part — which helps to lower the warranty costs that result from early failures.

Schafstall was early to recognize the complementary nature of this approach with the finite-volume method, which MSC.Software first applied to the simulation of forging processes in 1999. As a long-time partner with that company, he had early access to the technology, and immediately started applying it to 3-D hot forging processes that until then had been “unsolvable,” or took so long to solve that they were impractical.

Today, the finite-volume method of Simufact.forming continues to be the most accurate and cost-effective solution method available for solving complex 3D material flow. On a desktop or laptop computer with a dual- or quad-core CPU, most simulations can be run within an hour simulation time. Only the most complex of cases will require longer, but seldom longer than an overnight run. For those extreme cases, it is possible to run the simulation on a dedicated Linux server.

Simulation of a typical cold-forging process: In this example, the part, a knurledheaded screw, is compared with the actual part through each step of the forming process. Inset: Simulation of a typical hot-forging process: The forging simulation for this titanium turbine blade takes only 40 minutes when using parallel computation on a Windows workstation with a dual quadcore CPU.

Program development
At the end of 2006, MSC.Software decided it would be in the best interest of end-users for the company to divest its manufacturing software products, MSC.SuperForge and MSC.SuperForm, to the company established by Schafstall and Wohlmuth.

Given this opportunity, Schafstall aggressively pursued his vision of creating a fully integrated product, combining the power of both technologies to provide unprecedented capabilities to designers and CAE analysts alike. A typical example, where both technologies complement each other is calculating die stresses and tool damage during a complex 3D hot-forging process. The complex material flow is best calculated using the finite-volume method, while the tool is best analyzed using the finite-element method.

The initial release of Simufact.forming has been well received by the end-users, and there is great anticipation for the next release due later this year. A preview of the new features, which are expected to be released this summer, were presented at the recent Wire 2008 conference (www. wire.de) in Dsseldorf, where Simufact release 8.1 was introduced to considerable positive attention.

Development partnerships and reseller partnerships were entered during 2007 to establish a global presence. Recently, Simufact opened an office in Michigan — Simufact- Americas LLC (visit www.simufact-americas.com) — to provide the same level of service in the Americas that made them successful in Germany.