Promess Inc. recently achieved a milestone by delivering its largest Electromechanical Assembly Press (EMAP) Workstation to date. Weighing in at 21,000 pounds, the 500-kilonewton EMAP workstation stands 12 feet tall with a footprint of 7 feet by 7 feet.

The workstation was originally developed for a gear-pressing application in the aerospace industry, for which precision and repeatability were paramount. The ram has a 400 millimeter stroke; it can move at a maximum speed of 75 millimeters per second; and it provides micron-level accuracy.

Despite its bulk, the giant press is really no different than the company’s smaller models, says Glenn Nausley, president of Promess. “It’s our standard technology—it’s just up-sized,” he explains. “The frame is beefier to minimize deflection when applying such high force.”

Large or small, the EMAP is a servo-controlled, ballscrew-driven press equipped with a load cell to measure force and an encoder-based servomotor to measure distance. The press can precisely apply force and distance while measuring the functional result and feeding that data back to the control system. This ability to monitor the time, force and distance parameters of each press stroke allows manufacturers to effectively “clone” each assembly and ensure it meets specifications despite slight variations in the parts.

Force and position signals can also be processed by the press controller to provide a graphic “signature” of each cycle. This signature can be compared to a known good signature to ensure consistent quality. Assemblies that fall outside the signature are flagged as rejects.

Applications for assembly presses typically require much less than 10 tons of force. In fact, most applications fall in the range of 2,000 to 12,000 pounds. However, a small number of applications require very high forces, indeed. Some, such as pressing railroad wheels onto axles, are simply scaled-up versions of standard press applications. Others are more specialized. These include compressing metallic powder for rechargeable batteries or compressing “energetics” for explosive charges.

For more information on presses, visit or visit the company’s booth at The ASSEMBLY Show. Promess is one of at least six suppliers of presses that will be exhibiting at the show, which will take place Oct. 22-24 at the Donald E. Stephens Convention Center in Rosemont, IL. Besides suppliers of presses, you’ll find 225 suppliers of robots, automation, motion control technology, parts feeders, fastening tools, software and other assembly technologies. For more information, visit