Making the Leap: Air vs. Servo Feeds

John Waddington

Coil feeding is the process of transferring metal from the coil into the press. Feeding the coil precisely, quickly, and without damaging the material is paramount to your operations. Coil press feeding works hand in hand with other front-of-line metal stamping operations. With two major modes of feeds dominating the market—air feed and servo feed—optimization is the name of the game. Innovations in the form of close loop high-speed coupling lines and integration of Industry 4.0 capabilities are allowing companies to do more with fewer production steps, maintain smaller footprints, and provide safer conditions.

Air Feed vs. Servo Feed

While many different feed solutions exist, air feeds and servo feeds are among the most popular. Air feeds have been the industry staple since the early 1980s. They’re typically cost effective and work great on dedicated lines. They’re especially useful in feeding many types of shapes or extrusions that aren’t easily rolled with a servo feed. However, there are also challenges with air feeds. They can’t decelerate at the end of the stroke, which can cause problems. They’re harder to because they’re at the mercy of the air pressure, which can fluctuate greatly. They’re harder to get synchronized with the stroke of the press. They also require more maintenance and a longer changeover time between projects. Servo feeds can address these issues.

Servo feeds were created in the 80’s and are becoming the industry standard. Known for their precision, safety, efficiency, minimal floor space, and speed, servo feeds don’t have the length limitations that air feeds have. With an air feed, you have to manually adjust it to meet the part width and length the project requires. With a servo feed, you can simply pull up a job that’s already programmed into your control package, reducing downtime.

Making the Leap from Air to Servo Feeds

When is the right time to transition from an air feed to a servo feed? For many of our customers, maintenance plays a big part in the decision. Because air feeds use air, there are seals, springs, and a lot of moving parts. So, if you’re rebuilding an air feed every four to six months, you’re facing significant downtime and maintenance costs. Often, our customers are apprehensive to make the switch to servo feeds because they seem like a big investment. However, we help our customers evaluate the benefits of servo feeds—such as quicker changeover times, fewer moving parts, and less maintenance—and determine the return on investment, and they often find the servo feeds pay for themselves very quickly.

For example, one customer we worked with was running 60 strokes per minute with his air feed. He implemented a servo feed on his line and was running 180 strokes per minute, tripling his production. Another customer estimated their payback on the feeds we implemented was three months—so every three months, they were making as much as the feed cost in new product.

In addition, we’re currently working with a customer to help transition his 12 air feeds to servo feeds. While he was initially apprehensive to make the upgrade because he didn’t want it to fail, once he saw the benefits with his first implementation, he made the decision to switch all of his air feeds to servo feeds. We’re currently helping him implement his fourth and fifth servo feeds.

Safety Considerations

We understand that safety is a top priority in your operation. Failing to provide safe working conditions can result in injuries, labor issues, and production constraints. We go to great lengths to guard our equipment and work with each customer to identify additional guarding needs. We can help with fencing around the feed, and our feeds have safety circuit inputs that you can tie in your SIL level 2 or level 3 safety circuits.

High-Speed Close Coupling Lines

We’re so invested in safety that we’ve created the only high-speed precision close coupling line on the market—an innovation we developed to solve a safety issue one of our customers faced. The customer had high-speed servo feed lines with traditional loops, so when they pay off their material, it goes into a loop and then a feed. The customer sought out our expertise to help figure out a way to get rid of that loop of material. Press Room engineers created a close coupling line that’s able to work at a high-speed application. With half the space requirement of a traditional feed line, your operation can become even more efficient. It’s designed to be integrated with other feeds and offers analytic features for diagnosing issues. By removing the traditional processing loop, the line also removes safety concerns.

Whether you want a full line makeover or enhancements to your current equipment, our professionals have the expertise to help you evaluate what capabilities would be most beneficial to your application.