HMI enhances production uptime and control

A human-machine interface (HMI) dashboard connects a person to a machine or system. HMI software applications graphically present information to operators about the state of various processes in a format that looks like the actual machine or its display panel. The information can be accessed locally at the machine, remotely within the plant, or offsite via PC, laptop, or smartphone.

In aerospace forging, next-level HMIs enable operators to see how equipment is functioning and anticipate how it should perform, accomplished with dynamic animated models and schematics, live trending, and diagrams.

“Cutting-edge HMIs are visual learning tools for forging operators to observe the normal machine operation, to expedite troubleshooting when something goes wrong,” says Bill Goodwin, vice president of sales and engineering, Erie Press Systems. “Less experienced personnel can look at a well-designed HMI screen, watch the press run, and learn how it functions. Operators can monitor live press positional and force data as the machine transitions through the production cycle. When something’s out of sequence or stops abruptly mid-cycle, they can quickly troubleshoot, because the HMI provides a graphical window into the machine control system and its processes, identifying problem areas.”

Traditional limitations

With massive forging presses wielding tons of force to shape workpieces, maintaining production uptime and minimizing unexpected repairs and maintenance is critical.

However, manufacturers have had to rely on experienced operators using manual gauges to take a momentary snapshot of an individual component’s condition. While useful, this wasn’t comprehensive, and if problems weren’t caught in routine maintenance, costly production line breakdowns resulted.

“With manual gauges, if a pump started to fail, the operator might not notice until the machine was unable to complete a cycle,” Goodwin says.

Often, newer operators didn’t have the experience to recognize if forging equipment was operating as it should. If problems occurred, they frequently wasted valuable time trying to track down experienced operators or technical documentation.

HMIs in forging

Aerospace forging presses with advanced HMI capabilities help operators see and monitor what’s happening with insight to successfully troubleshoot and promptly get the equipment back online.

Although HMIs are becoming popular, distinct differences in capability between basic and advanced, next-level options exist. Rudimentary HMIs are visual terminals where information can be entered and data viewed, but no new information stored.

In contrast, advanced HMIs enable saving/retrieving data, custom searches, and display of historical trends. Up-to-date PDF technical documents and the schematics of each component on the machine are searchable and can be quickly displayed. However, the most distinguishing capability of advanced HMIs is how software applications ease operator understanding and control of the forge press, along with any troubleshooting.

Next-level HMIs provide dynamically animated schematics allowing the operator to watch the forging equipment while it’s running. Operators can quickly drill down from a top-level animated schematic to review the performance of specific press components, such as valves and pumps, and to locate information on part numbers and wiring schemes.

Erie Press starts with a digital SolidWorks model of the press, imports it into HMI software, and then breaks it apart and dynamically animates it, while displaying vital operational statistics.

In the case of an animated hydraulic schematic, the hydraulic pressure source from multiple pumps is displayed in one location for instant verification. The operator can monitor the current press status displayed in a text box, as well as fields indicating the pressure in the main and pullback cylinders. The valve command and actual spool feedback are displayed for each proportional valve.

The press operator can also monitor main ram tonnage, main cylinder pressure, moving platen position, last cycle time, and current cycle time.

Forge personnel can more effectively learn the press’s internal operation by observing this data as the press cycles through operation, quickly diagnose, and act if there’s a potential issue.

Improved diagnostics

Ajax-CECO-Erie Press developed an online diagnostic system for remote monitoring and support through a remote Ethernet diagnostic connection provided on all new equipment. The Ethernet-based control system provides engineers with a platform to remotely view the machine’s health as it’s operating.

“The goal is to avoid production downtime by preventing problems as well as reducing the time to find, diagnose, and solve them,” Goodwin says. “Remote diagnostics allow us to monitor the forging equipment to resolve any potential issues promptly. For example, we can remotely reset a switch that didn’t activate or fine-tune the target position or precise speed of the press ram.”

According to Goodwin, such capability – along with implementing some redundant components such as electronic position transducers – can keep production online even if one component fails. “If one sensor fails, we can dynamically switch to the good one. Traditionally, one failed transducer leads to downtime until a technician can acquire the correct part and change it out on site,” he says.

The system also enables viewing of historical trends and up-to-date, searchable PDF technical documents and schematics, as well as dynamic animated schematics.

“With historical data, if a component is starting to fail, maintenance can often identify and replace it before catastrophic failure,” Goodwin says.

Next-level HMIs enable a historical review of how forging equipment functioned at specific dates and times. When the operator simply pins certain types of data or moves a graphic slider representing a slice in time, the HMI displays the data on how the forging equipment performed at the specified day and time.

In the case of Ajax-CECO-Erie Press, forge equipment with an HMI includes a library of datasheets for its electrical, mechanical, and hydraulic devices. Electrical schematics, hydraulic schematics, and mechanical assembly drawings can be viewed and printed from an HMI. The data sheets are in PDF format, which enables keyword searching within the document.

Next-level HMIs enable drilling down from a high-level, dynamic, graphic animation of the equipment to quickly zero in on the specific data, schematic, or drawing required.

“For example, at a dynamically animated schematic screen on the HMI, the operator can hover over a particular device to find the exact manufacturer’s part number or click on the device to access its specific datasheet,” Goodwin explains.

While aerospace forging presses are traditionally viewed as decades-old technology, advanced HMIs are becoming as simple to monitor and use as an operator’s smartphone, making critical performance data readily available.

About the author: Del Williams is a technical writer based in Torrance, California.