Page 22 - MetalForming November 2014

Servos Seeing
More Service
—Part 2
More than a decade after they debuted in North America, servo presses have entrenched themselves and have increasingly pop- ulated the metalforming landscape. In Part 1, (September 2014), MetalForming explored servo trends and markets with Seyi, Stamtec and Minster. Here we
explore the topic with press builders Aida, Komatsu and Schuler.
Slow, steady growth followed the introduction, in 2000, of Aida’s direct- drive servo presses in North America, as metalformers considered how they might apply the technology to their applications. In 2010, though, sales
began to explode, according to Bob Southwell, Aida-America’s vice presi- dent of sales and marketing. This “explosion” has resulted in more than 1600 Aida servo-press installations globally, with 200 of those in North America.
“The driving factor was the auto- motive market,” says Southwell, “as the technology made its way from OEMs to Tier One and then Tier Two suppliers. Rising use of servo-driven press tech- nology in automotive can be further traced to the new materials being developed and used in response to ris- ing fuel-economy requirements and increased vehicle-safety efforts. More parts are being designed using high- strength steels (HSS) and advanced high-strength alloys. And, the growing use of aircraft-quality aluminum, a very tough material to form, also contributes to the increased use of servo-press technology.”
The Challenges of HSS
Especially challenging with HSS, notes Southwell, is that while the steel requires a listed minimum tensile strength, no upper limit is required.
“As a result, material can vary great- ly from coil to coil,” he says. “While one coil may make a decent part, the next coil produces bad parts. With servo-driven presses enabling restrik- ing operations and close control of the forming cycle, metalformers can achieve much more consistent and precise forming.”
Work-hardening also spells trouble when working with HSS.
“Striking HSS once will workharden
This 1500-ton-capacity Aida servo-driven transfer press illustrates how servo technology has been scaled upward and applied to larger-tonnage presses capable of precisely forming materials used in current automotive designs.
20 MetalForming/November 2014
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