Although today’s forging industry is the result of more than a century of process developments, forging presses are delivering better results thanks to the capabilities of HMIs to improve production uptime and process control. A Human-Machine Interface (HMI) is a user interface or dashboard that connects a person to a machine, in particular to a forging system. HMIs are software applications that graphically present information to operators about the state of various processes in a format that looks like the actual machine or display panel. The information can be accessed locally (at the machine) or remotely (within the plant or at an offsite location) via PC, laptop, or smartphone.
For forging, next level HMIs are aiding operators not only to see how equipment is functioning but also to anticipate how it should be performing. This is 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,” said Bill Goodwin, vice president of sales and engineering, Erie Press Systems.
“Even less experienced personnel can look at a well-designed HMI screen, watch the press run, and then learn how it functions. Operators can monitor live press positional and force data as the machine transitions through the production cycle. When something is 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,” Goodwin added.
Erie Press, founded in 1895, offers a line of standard mechanical forging presses as well as individually engineered hydraulic presses for most any forging application (closed die, open die, and ring preforming), as well as metal forming, cold extrusion, isothermal forging, carbon extrusion, composite presses, and stretch forming machines.
Erie Press was acquired by Park Ohio 2019 and now it’s part of the largest forging equipment supplier in North America, Ajax-CECO-Erie Press.
Traditional limitations -- With massive presses applying many tons of force to shape workpieces, for automotive, aerospace, mining, and rail, maintaining production uptime and minimizing unexpected repairs and maintenance is critical. However, manufacturers with forging equipment have long had to rely on experienced operators using manual gauges to take a momentary snapshot of individual components' condition.
While useful, this was not comprehensive: if problems or defects were not discovered in routine maintenance, they would remain undiagnosed until a press or production line broke down, resulting in unplanned costs as well as losses in production.
“With manual gauges, if a pump started to fail, the operator might not notice until the machine was unable to complete a cycle.” Goodwin said.
Often, less-experienced operators could not recognize if forging equipment was operating as it should. Complicating matters, if problems occurred, they frequently wasted valuable time trying to track down experienced operators or technical documentation.
“At times, a forging machine would stop and no one knew what was wrong with it, why it stopped, or where [in the production cycle] the error occurred,” said Goodwin.
HMIs in forging -- Forging presses with the most advanced HMI capabilities help operators to see and monitor what is happening with enough insight to successfully troubleshoot and get the equipment back online promptly, when required.
Although HMIs are becoming more common, there are differences in capabilities between basic and advanced, next-level options. The simplest HMIs are visual terminals where information can be entered and data viewed, but no new information is stored.
Advanced HMIs make it possible to save/retrieve data, initiate custom searches, and display historical trends. Far from rudimentary, up-to-date technical documents (PDFs) and the schematics of each component on the machine are searchable, and can be quickly displayed, as needed. However, the most distinguishing capability of HMIs is how the software applications ease operator understanding and control of the forging press, along with any necessary troubleshooting.
In fact, true next-level HMIs provide dynamically animated schematics that allow the operator to watch the forging equipment while it's running. Operators can “drill down” quickly from a top-level, animated schematic to review the performance of specific components, such as valves and pumps, as well as to locate information on part numbers and wiring schemes.
Goodwin said that Erie Press HMIs start with a digital SolidWorks model of the press, import it into HMI software, and then “break it apart” and dynamically animate it, while displaying critical operational statistics.
In the case of an animated hydraulic schematic, for example, the hydraulic pressure source from multiple pumps is displayed in one location for instant verification. The operator can monitor the current state of a press 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.
According to Goodwin, the press operator also can monitor main ram tonnage, main cylinder pressure, moving platen position, last cycle time, and current cycle time.
Using this information, forging personnel can learn the press's internal operation more effectively by observing all this data as it cycles through operation to enable quick diagnosis, and action if there is any issue.
Whether for the forging operator or OEM, in terms of preventive or troubleshooting diagnostics, the integration of HMIs, sensors, and online technical support also has progressed a long way.
As an example, Ajax-CECO-Erie Press has 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 OEM engineers with a platform to view the machine's health remotely as it is operating.
“The goal is to avoid production downtime by preventing problems as well as reducing the time to find, diagnose, and solve them,” said Goodwin. “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 capabilities – along with implementing some redundant components like electronic position transducers – can keep production online even if a component fails. “If one 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 said.
Goodwin noted that such a system also allows 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 often can identify and replace it before catastrophic failure,” said Goodwin.
He points out that next-level HMIs offer a historical review of how forging equipment functioned at specific dates and times. When the operator “pins” certain types of data or moves a graphic slider icon representing a slice in time, the HMI displays data on how the machinery performed at an exact date and time.
For Ajax-CECO-Erie Press, forging 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 is available for keyword searching.
“Instead of spending days trying to locate the right technical documentation and reading through data sheets or wiring schematics that can be 100 pages long, the data is searchable and immediately available to operators,” Goodwin said.
In fact, next-level HMIs take search capability further by supporting “drilling down” from a high-level, dynamic, graphic animation of the equipment, quickly“ zeroing in” on the specific data, schematic, or drawing required.
“For example,” Goodwin continued, “at a dynamically animated schematic screen on the HMI, the operator can hover over the device to find the exact manufacturer's part number or click on the device to access its specific datasheet.”
Forging presses may be based on decades-old process technology, but advanced HMIs are making them virtually as simple to monitor as an operator's favorite smartphone, while making critical performance data readily available too.
The bottom line for manufacturers relying on the efficient use of forging equipment is that new capabilities can significantly increase production uptime and profitability, providing a critical edge over competitors.
Del Williams is a technical writer in Torrance, Calif.