Move up to Servo (Roll) Feed Technology

 Contract stampers, job shops and integrated stamping houses continue to strive for better part quality, part consistency and increased productivity, while at the same time maintaining the necessary flexibility to respond to today's dynamic market. They are continually forced to evaluate the type of equipment and technology feeding their punch presses. The most profitable way to accomplish such a challenge is through an investment in servo feed technology.

 

Accuracy is the name of the game

 

     Servo feed technology incorporates efficient operating characteristics to best help the press produce more consistent parts at closer tolerances and higher operating speeds. Today's advancements in servo feeds give the user a more operator-oriented control for maximum utilization. The advantages of implementing servo feed technology in the stamping environment have never been more obvious. With absolute positioning accuracy of +/- .002" or less, the user can provide their customers with more part accuracy than previous conventional processes. What this means to the servo feed user is that it alleviates the potential for supplying their customers with parts that are not to specification as well as decreasing the potential scrap and returned freight costs. The accuracy of servo feeds also provides the user with increased tool life. Tool longevity is the result of accurate placement of the feed progression in relation to the dies pilot pin. This minimizes premature pilot wear and the costs associated with regrinding pilots and repairing dies. In addition, with consistent and highly accurate feed progressions, thick scrap webs can be reduced to a minimum by providing the user with higher yields per coil, reduced scrap loss and resultant profits from each job. Some servo feeds give you the flexibility to refine your feed lengths while in motion at .001" increments. This allows the user to quickly and easily refine the setup as well as provide good control of the size of the scrap zone.

     Other unparalleled advantages of servo feed technology are the continued advancements in productivity. Speeds of servo feeds are currently operating in excess of 1400 strokes per minute. This combined with their quick setup to good part capability; make the servo feed the press feed alternative. Trying to find a feed to match up to the impressive press speeds of today is no longer a difficult task. In fact, most servo feeds provide you with the ability to customize feed speeds to optimum punch speeds and conditions. Some of the more recent preferences in productivity enhancements of servo feeds has been the need to store jobs of previously run parts so that when the need arises to repeat a job run, all that is required is to call up the previously stored job number. The stored job includes all the pertinent parameters of the previous job, so setup time is quick and efficient. Some state of the art stampers take job storage to the next level by downloading jobs to the feed control on the shop floor via a host computer and RS232/422 interface. However, should you prefer to run your jobs manually, some feed controls offer a prompting display to quickly and easily walk the operator through the parameters to be set and designated through the proper sequence for setting up that first time job or editing a previously stored job.

 

Job flexability is a key advantage

 

     Another control parameter that enhances productivity is the ability to set a batch count for a specific job requirement. This ensures that not only enough parts are made and automatically counted for a specific job, but also it safeguards from producing too many parts and thus prevents the possibility of excessive inventory and resultant overhead. Another advantage in servo feed productivity is its ability to feed very long lengths in one cycling at a very high rate of speed while maintaining accuracy. Older conventional technology feeds require gripping of the material to ensure proper feeding progressions were maintained, while at the same time requiring multiple strokes in order to complete a specific feed length and part size. This type of feed is much less productive than servo feed technology and can also be detriment to its esthetics.

 

Today's material diversity requires a Servo (Roll) Feed

 

     With today's diverse market demands, servo feed technology excels in its capability to do more with your press in less time. The servo feed allows users to run a broad range of materials, thicknesses, widths and feed lengths very effectively. Because of the ability to adjust the roll pressure, running pre-painted, embossed or exotic materials are more conductive to servo feed technology. Even highly sensitive materials can usually be run in a high performance four roll servo feed design. The traction of four feed rolls allows the use of less roll pressure therefore minimizing material marking. In addition, varying material thicknesses are automatically accommodated with self-adjusting heights of the feed rolls. Narrow width materials are easily accommodated by most servo feed manufacturers through the use of adjustable roller guides to maintain proper centering of the coil feeding process. Servo feed technology flexibility is more desirable when interfacing with complex system controls where there is a requirement to monitor total cell performance. The design characteristics inherent with servo feed technology fit well into today's just-in-time manufacturing mentality. With the market's future emphasis directed toward competing in the highly competitive and volatile global business environment, it is apparent that suppliers incorporate a feed that will provide the customer with U. S. and metric dimensioning capability. Servo feeds allow users to better serve their customers changing market and manufacturing needs as they expand manufacturing capabilities abroad. It also best complements press users with quick die change requirements, too. In addition, it is the most adaptable feed design to interface with complex flexible fabrication/gag tooling as well as CNC machinery like punch presses, roll formers, shears and laser cutting systems, even future technologies not yet applied. An additional innovation of servo feed technology is its ability to incorporate diagnostic functionality. Diagnostic feedback allows the user to identify possible faults such as a drive fault, position fault, feed enable fault, no loop fault or incomplete data notification. Often a fault can be identified and corrected through proper communications of the display status at the particular moment.

 

When reliability is critical

 

     Servo feed technology has been implemented in stamping environments for more than three decades. Aside from many of the above mentioned benefits of moving up to servo feeds, the real success and recent explosive growth of these feeds has been due to their impressive reliability and the high performance users have experienced in the press room. As you are well aware, most stamping environments are very demanding with rugged operating conditions. Because servo feeds have proven their ability to withstand even the most challenging environments over the last decade, some manufacturers support their confidence in the technology with a standard two-year warranty. Unlike the older conventional feeds that required seals, pistons, consistent air pressure and air quality, servo feeds require a lot less maintenance scheduling due to their simplification in design and nature of operation.

     With the above benefits of servo feed technology, what are the disadvantages? The most often PERCEIVED disadvantage, if you wish to call it such, is the cost. Even though servo feed prices have come down in the last few years, they will probably never drop below conventional feed technology. However when measured on a value basis, the benefits of the servo feed accuracy, productivity, flexibility and performance provides the user with an incomparable competitive advantage.

Is a Servo (Roll) Feed right for your operation

 

     It's obvious that servo feed technology brings a lot to the table for the end user. However despite all the benefits of servo feed technology, management must make the commitment to evaluate the processing capabilities of the whole coil system that is feeding their presses. Such an evaluation may require replacement or modification of some existing coil system components so they match the production capabilities of the feed and press; or in some cases, a completely new coil system may be required in order to bring the line speed up to that of the press. So before committing to improved servo feed technology, you must analyze your complete coil system. Remember your line is only going to be as productive as the slowest component-no matter how much you spend for the latest press and feed technology.

 

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