For too many years the press room has had it too easy. Sloppy shop practices and under- utilized press time were commonplace, but not any more. Competition among domestic and foreign manufacturers makes it a necessity that today’s pressroom be as efficient as possible.

Companies today are looking for ways to run faster, as well as smarter. Investment in the proper metal working machinery is, more than ever, the most critical decision that a stamping room supervisor has to make. From my vantage point as a supplier of new feeding and production-enhancing equipment modifications to the metal stamping industry, I can see many areas where improvements can be made. Some of the areas where I see potential for huge increases in productivity involve the uncoiling, straightening, feeding, and in some cases rewinding of coiled strip.

In the past, electrical controls applied to coil handling equipment were marginal, at best. Upgrading of older electrical control systems on straighteners and uncoilers and replacement of old inaccurate press feeding equipment can improve production rates by as much as 300%. It can also eliminate waste and scrap, allowing some manufacturers to also eliminate the dumpsters at the end of the production line.

It all starts here. Loading of coils is an area where countless hours are wasted due to damage to the strip incurred during the loading and uncoiling of material. Coil cars can significantly cut coil loading times as can the use of double ended uncoilers which allow for the loading of a new coil while the previously loaded coil is running. Pallet decoilers have helped save manufacturers thousands of hours of down time.Today’s press room must be able to change over a job in minutes, instead of the hours that were traditionally allotted. Powered uncoilers that spill material onto the floor need to be retrofitted with modern regenerative drives that can quickly accelerate the coil up to line speed. Just as important, they can decelerate the coil to a stop so that material never comes in contact with the floor. This prevents damage and marking of the strip. In addition, it helps to keep dirt and other contaminants from being picked up by the strip and transferred to the down- stream equipment and tooling. (Would you throw sand in the carburetor on your car? Cement dust is nothing but sand, and it ruins tooling.)

Although the technology for straightening material has not changed, the ways in which you can control a straightener have changed. The problems with starting and stopping straighteners are similar to uncoilers: they can overrun the loop, spilling material onto the floor, which damages the material and contaminates the strip and then down-stream equipment. In addition, starting and stopping straighteners can put marks in the strip, affecting the straightness of the material.

The most technologically advanced machines on the market have provisions for digital readout and automatic positioning of the straightening rolls, as well as high performance drive systems and loop controls that can keep the straightener from stopping between press operations.

In some cases a creep mode is employed to keep the straightener from stopping for up to several minutes, while the press operator performs adjustments to the line. For most pressrooms, however, this level of ultra-sophistication is not required. Simply replacing mechanical speed variators and start/stop clutch/brake systems with a modern variable speed control system allows better control of the machine and allows for much more consistent operation of the line.

Since the loop between the straightener and the press feeder has an effect on feeder performance, it is critical that the loop size be consistent from feed to feed so that variations in feed length (and the resulting problems) do not occur.

This is an area where major technological improvements have taken place and where spending money on new equipment can easily be justified. An accurate feeder can improve die life, eliminate scrap, and in many cases double and triple production rates.

Modern servo-driven press feeders practically eliminate feeder setup time and can, in most cases, produce a good part from the first press stroke. The trial and error associated with adjusting mechanical and air feeds are eliminated. New methods of threading tooling and inspecting strip location between press hits are available and form the basis for new troubleshooting methods.

The jog-to-length features that are available on some servo-driven feeds allow starting and stopping of the strip as stock lifters and guides are encountered during threading of complex progressive dies. The feed will automatically stop at the programmed distance, so guesswork about what is happening with strip position is eliminated.

Once the correct feed progression is known, future setups of the job can be performed in seconds and the wear and tear from not-quite-correct feed settings are eliminated. Many customers report die life increases as large as 200%.

Customers that presently use air feeds can expect production rate increases as large at 300 percent by reducing setup time, increasing press speeds, and eliminating scrap product due to misfeeds and careless setting of mechanical feeding apparatus.

Many companies are also purchasing servo feeds for their die try-out presses and short run stamping lines because they know that if they are having problems with a new die, the problem is really with the die and not the feeder. Extremely accurate tool room reference feeds are available with accuracy’s to +/-.0005 and better.

Gag Tooling --- Just as the unique capabilities of servo driven feeds make new die setup and troubleshooting techniques available, they also make new manufacturing techniques possible. Having a feed that can locate markings or pre-punched areas on the strip, feed backwards as well as forwards, and feed patterns of moves, as well as control other equipment like GAG tooling, cutoffs and secondary presses, cylinders and welders, brings many new possibilities to the tool designer.

Entire families of parts can now be created on one press with one tool. Simply programming in a part number calls up a series of pre-programmed instructions that the feeder will follow during the pattern of moves and operations that are required to complete complex parts with simple tooling.

After improvements have been made to existing equipment, the next challenge to the setup person is making the required adjustments to the press cam switches to synchronize the operation of auxiliary equipment with the press. If you have just spent money on upgrading feeding and coil handling equipment to enable you to set up faster and run at higher line speed, it would not make much sense to get out a step ladder and climb up on the press to set the cam switches.

In order to maximize the performance of any stamping operation, precise timing adjustments must be made. Once these settings are determined, it is essential that the settings be easily reset when the time comes to run the job again. Although electronic cam switches have been available for several decades, it is only recently that they have become easy enough to use and smart enough to perform the data storage and recall that is required for single-button setup.

Because of the time involved and the number of settings required, instant recall is essential. This allows less skilled operators to recall complex setups for quick change over's and maximum performance every time the job is run. It also eliminates confusion when things go wrong. Setup people can eliminate the possibility of wrong settings because they are exactly the same settings that worked last time. Sometimes when you have a problem it helps to know what isn’t wrong, so you don’t waste time looking in the wrong place for a solution.

Now that you have that job that ran at 60 spm with 100 percent inspection running at 180 spm right into the shipping cartons, it’s time to protect the tooling. Often dismissed as too complicated and difficult to use, die protection systems now combine the hardware and software technology with ease of use that cam switches now possess. In fact, new die protection systems include cam switch functions, as well as tonnage monitoring and other features that protect your press, tooling and personnel.

In the past 15 years I’ve seen some marginal operations completely turned around with the application of new controls to existing equipment. With the exception of feeding equipment, most existing machinery is able to compete in the nineties with the application of a little technology and a mechanical rebuild. Rebuilding of existing press feeders usually results in only a small increase in performance and is usually not cost effective compared with the performance gains afforded by the new designs that are now available.

One thing to keep in mind when upgrading the performance of your metalworking equipment: Its not how much it costs, but how much profit you are going make from increased production that counts. A little common sense in recognizing the importance of a small investment in upgraded equipment to future production and profitability goes a long way on the path of success.