Page 36 - MetalForming July 2011

Metalforming Electronics
By George Keremedjiev
Revitalizing a Used Mechanical Power Press, Part 6: Who will Drive; Where is the Road Map?
There is no shortage of auctioned mechanical presses, available for pennies on the dollar. And while the pre- vious five installments of this series addressed the press-related issues that must be addressed when bringing a used press to your shop floor, I often wonder how qualified shop operators, setters and maintenance personnel are to operate and maintain newly acquired used press.
Are your shop’s pressroom personnel up to the task of run- ning a press that may be radically different from any other press on the shop floor? Just how do they go about maxi- mizing the performance of this new arrival? Here are a few guidelines.
1 Create a technical library. If you want to see some of the most puzzled looks in a stamping shop, ask where the equipment manuals are located. The answers
are coupled with lots of hand waving and hemming and hawing. “They may be in
Why such a need? Well, everything from the proper coun- terbalance adjustments to the parallelism of the ram to the critical angle for the brakes, etc., are clearly delineated with- in these manuals. Without the press manufacturer’s data how do you know what the proper press setup and mainte- nance parameters should be?
2 Investinschooling.Ifthepressmanufacturerisstill in business, send your pressroom and maintenance personnel to them for training related to the newly
acquired used press. The manufacturer also may be able to conduct training inhouse at your location. In addition, there are independent press rebuilders and consultants who offer such training.
Just imagine the confusion on the part of your technical staff when faced with a press that differs greatly from any other press they have ever worked on or operated.
Use a fine-tooth comb. Sometimes, company pride 3 can prevent the hiring of an outsider to perform the necessary technology audits of a newly acquired used mechanical press. When a company lacks the required internal expertise and skills, there is great value in hiring a professional press rebuilder to take an honest look at your newly acquired used press. Why wait until the press enters full
production to learn that it may be mechanically unsound? As soon as possible after installing the used press in your shop, use a fine-toothed comb to ferret out any mechanical issues inapparent during the auction process. Better to dis- cover and repair any problems before the press is fully com- mitted to production runs, where a malfunction may dam-
age not only the press but the tooling as well.
4 Carefully document performance. Once the newly acquired used press is placed into the pressroom production environment, carefully document sev- eral parameters during its lifetime, including ram paral- lelism, accuracy of ram shut-height indicator, tonnage dis- tribution across the ram surface, and the critical stopping time/critical angle once the brake is applied. In fact, shops would be wise to document these parameters for all presses. Proper, timely preventive maintenance requires feedback from the floor to alert personnel to major mechanical-per-
formance deviations.
Be no less careful about what appears to be a bargain when
purchasing a used mechanical power press than you would be when purchasing an automobile. At least when purchas- ing a used car you likely will be able to open the hood, kick the tires and take it for a test drive. Hard to do this with a press during an auction, which compares to buying a movie after having only viewed a still-frame photo from the film. MF
maintenance...no wait,
they are up in engineer-
ing...come to think of it,
we really have not seen
any manuals in years,” is
the likely reply. Shops
should maintain a central-
ized and well-maintained
technical library for all
equipment, a place to go
when questions arise
about the proper operation/maintenance of any piece of equipment.
Shops should maintain a centralized and well-maintained technical library.
This proves particularly important for newly acquired used presses. Make every effort to track down not only the manuals for each press, but also any technical updates. This should be easy to do if the manufacturer remains in business; if not, an Easter-egg hunt results, involving searches on Google and EBay, and phone calls to press rebuilders and the like.
George Keremedjiev has been writing this column for more than 20 years. He regularly consults with metal- forming companies worldwide and provides metal- formers with training on the application and imple- mentation of sensors for die protection. For more information on his seminars and consultancies, con- tact:
Tecknow Education Services, Inc. P.O.Box6448
Bozeman, MT 59771
tel: 406/587-4751 | fax: 406/587-9620 www.mfgadvice.com
gk@mfgadvice.com
34 MetalForming/July 2011
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