Page 18 - MetalForming March 2012

Machine-Control
Obsolescence
Control obsolescence is an often-overlooked risk in today’s rapidly developing manufacturing environment. Any machine with an electronic control will at some point be exposed to obsolescence— are you ready to minimize the impact?
BY TODD WENZEL
It’s been a long time since we’ve been at full capacity! We can finally relax a little.
Use of electronic controls in the pressroom began decades ago. Before then, manufacturers were readily able to service nearly every aspect of what were more mechanical controls. This also is true of old machine controls that use relay logic—these units are serviceable with new relays when the originals no longer are available. Also, the lad- der logic in these controls—what would comprise a program in a PLC—is physically visible, easing maintenance and repair.
Fast forward to today. If an old PLC or solid-state control fails and you do not have a copy of the program, it becomes a black box. Repairing it is not a matter of simply replacing the parts; you also must replicate the logic circuit.
Parts and Service Becoming a Problem
Today we find that many of the older machine-control manufacturers no longer can service or provide parts for the PLCs they provided decades ago. Also, some manufacturers of production equipment have gone out of business. In this case, even if your controls aren’t that old, there may be no support for identifying the underlying logic required to oper- ate the equipment.
Todd Wenzel is president, TCR Integrated Stamping Systems, Wisconsin Rapids, WI; 800/676-2240; www.tcr-inc.com.
Don’t let unseen gremlins reach up and bite you
on the assumption that all is well in the pressroom.
Illustration by Craig O’Connor
Manufacturers of PLCs support their components for only a defined lifespan. Any machine with a PLC control will therefore, at some point, be exposed to obsolescence. Most controls using dedicated solid-state controls also will have this problem. In addition, some older machines were designed with software that requires DOS-based computers or emulators to view and update. This can make repairs dif- ficult if not impossible.
Certain electronic boards may no longer be available. In many cases they have been rendered obsolete due to reduced volumes and excessive manufacturing costs, or as part of a marketing strategy to drive customers to more current prod- ucts. Or, perhaps the original manufacturer has gone out of business and the technical data to reproduce the boards has been lost.
Risk Assessment
Metalformers must ask themselves four critical ques- tions when evaluating their susceptibility to control obso- lescence:
• What parts of the press cells are vulnerable to the risk? • Where is the greatest risk?
• What is the potential or likely length of lost production
time?
16 MetalForming/March 2012
www.metalformingmagazine.com