If it weren’t for powdered metal (PM) press equipment, the cars we drive would be significantly more expensive. Without a PM press, the alternative is using a CNC machining center, but as many fabricators know, producing components from solid metal takes a lot of time and labor and a fleet of machining centers if the goal is to mass produce a part. It’s just the nature of the subtractive process.
Producing a component from PM, however, is a quick process and one that can be leveraged for mass production. With just one machine and basic automation, hundreds of parts can be programmed to flow off a line with the simple press of a button.
According to John Reynolds, powdered metal press product manager at Cincinnati Inc. (CI), “if you had to machine a difficult gear in a lathe or drill press, it could take a day to make one part.” The labor alone could cost up to $200, he adds. But, with a PM press, “you’re looking at making up to 12 parts per min.,” and one operator could easily oversee multiple machines. The cost difference, to say the least, is vast.
“If it can be made out of powdered metal, the automotive engineers today will find one way or another to do it,” he says.
Usability for the masses
Considering the slew of ways that PM press equipment can outshine CNC machining centers, they can be found in shops all around the world. Because of their popularity plus the ever-persistent skills gap, machine builders are compelled to make their press equipment as easy to use as possible – CI included.
In fact, CI unveiled a brand-new upgrade for its press equipment at the PowderMet 2024 conference hosted by the Metal Powder Industries Foundation in Pittsburgh June 16-19. At the conference, company representatives introduced the new streamlined control system and human machine interface (HMI) that gives customers the ability to integrate with ancillary equipment, including robot, scale and orientation device interfaces. The new offerings enable the transmission of real-time operational data to the control to be displayed as detailed spreadsheets for production and operational analysis.
“The whole idea is to allow our customers to monitor and improve their processes,” Reynolds says. “We have a customer in Wisconsin that reduced their downtime by 15 percent after switching to the new HMI and control. That, of course, increased their productivity by 15 percent, too.”
Powerful benefits
One of the most powerful benefits from the HMI and control is the greater ability to collect data in real time. Gathering repeatability information simplifies machine monitoring for a variety of benefits, including, but not limited to preventative maintenance, troubleshooting and operational optimization.
“Not only is it easier to troubleshoot issues at the machine in real time, but you can reference a control log in the HMI for historical use in case something happened on the off-shift,” Reynolds says. “To find out what happened, you can just go back and look at the log and see where someone made a mistake and correct it, so it doesn’t happen again in the future.”
The new control also features a trainer mode, which was developed to ease the process of training new technicians on a machine’s various functions. To be in line with what customers expect out of today’s modern equipment – to be intuitive and easy to use. And, if customers prefer to use an alternative HMI, that’s okay, too, because CI’s new HMI can work in unison with other brands.
“Our HMI is a Windows-based system that works in tandem with an Allen-Bradley CPU,” Reynolds says. “The HMI is primarily for display – to turn a function on, collect and display data, those type of things – but the principle part that actually runs the machine is in the Allen-Bradley unit.”
While the Allen-Bradley CPU is, essentially, doing the heavy lifting for the machine, the importance of the HMI cannot be understated. With persistent labor issues, machines these days need to be super simple and feel familiar to users right out of the gate. None of this was lost on the developers at CI.
“There are staff that know everything about how the machine operates, but then you have the other guy that only knows a little about how it operates,” Reynolds says. “It has to be easy to use, but in the case of a new operator, we have stages of access in the control where we can limit access to certain functions to where only a supervisor or approved operator can gain access via a passcode.”
In terms of the Windows-based HMI, it offers the ability to program a variety of machine functions. If a customer wants to put a lubricant in the die at a certain time, all they have to do is push a button on the touchscreen and it will automatically spray the die at every stroke. These programmable buttons are used for a variety of other functions and ancillary equipment, too.
Furthermore, because the control is IP-address oriented, it can be networked with other machines, so that customers can monitor each machine from one location.
“Let’s say you have four lines of production; two of them make the same part, be it bushings or little steel parts,” Reynolds explains. “If one of the two machines that make that part is having issues, networking these machines together creates the capability of shutting the one down, increasing the production of the other one and then slowing the production down on the other two. This reduces interference with the overall production of parts. It might slow down the line a bit, but you don’t have to shut the whole thing down.”
Another perk of the Windows-based control is its graphics and reporting capabilities. “If a customer has a part that took them a while to get it exactly where they want it, they can save that graph for comparison if they start to have issues with the part down the road,” he adds.
Going deeper
For hydraulic machines, the control system displays the actual servo valve position to the operator, aiding in troubleshooting and allowing for preventative failure analysis. These insights mark a significant shift from the controls available on early PM press equipment.
“Our first machines were relay control,” Reynolds explains. “Operators would push a button to turn one relay on, which then turned on the next relay. A relay box on the backside of the machine ran off the gearing that turned on each relay in sequence to turn on different functions on the machine.”
The new control, however, integrates all the computer functions into one circuit board with separate inputs and outputs, which enables faster setups and easier programming.
“We can even control the PM better than how we used to,” Reynolds says, “which opens up so many more applications for PM presses. For electric vehicles (EVs), it’s incredibly important to be able to control the compaction of the PM to where it isn’t heated up – just by the virtue of friction, the PM can be heated up during the compaction process if it isn’t precisely controlled.
“This is particularly useful with magnetic PM,” he adds. “Being able to compact magnetic material well enough to keep the heat down is big – when you keep the heat down, you don’t destroy the material’s magnetic characteristics.”
This new control and HMI essentially mean that the days of manual adjusting the machine are ancient history. With all the pneumatics now on the HMI, customers no longer have to make any adjustments at the back of the machine.
“You just go on the screen and select ‘60 PSI’ on a certain surface to automatically make the adjustment,” Reynolds says. “This type of control also helps customers with automation. Instead of having to go around the robot to work on anything on the machine, everything can be monitored from the HMI. Light curtains can be interfaced via the HMI, too.”
PM fundamentals
CI has been making PM presses since 1962, which is around the same time that the automotive industry started outsourcing some of its work. Originally, the Fords and Chevys of the world produced the bulk of their auto components in-house, but as time passed and production levels increased, they sold their equipment to tiered suppliers that could support them with parts so that they could focus on assembly.
The first standard PM presses used by the automotive industry were comprised of an upper and lower hydraulic cylinder with dies in between that were filled with PM. Once the die was filled, the hydraulics would come together to compact the PM to create a solid part.
At CI, parts can be retrieved manually or by a pick-and-place robot that transfers the part to a conveyor belt, pallet or bin. When the part comes off the machine, it’s referred to as a green part as it is not fully complete. To finish the process, the green part is placed in an oven where it is heated up to as high as 1,300 degrees F.
“The oven doesn’t heat up the part to where it becomes fluid, but it does impart enough heat to excite the molecules in the PM to where they adhere to each other to make the part more solid,” Reynolds explains. “When the process is complete, you’ll have a part that is about 75 to 80 percent the strength of a part that you could have made from a solid piece of steel.”
To provide an example, Reynolds mentions an aerospace customer that makes parts for jet engines on a CI PM press from a specialty PM. Like many green parts, the customer’s components are heat treated at high pressure and high temperature.
“The material they use is a specialty PM that is extremely hard once it’s run through the furnace,” he explains. “They have to grind it for shape, but it makes it a whole lot easier than trying to grind a whole intake ring on a jet engine from the ground up.”
Iron and aluminum are the most common PM used, but like Reynold’s aerospace customer, it’s fairly standard for fabricators to use specialty PMs or combinations of PMs, depending on the part being made. Considering the array of parts that can be produced with PMs, CI makes machines ranging in size from 66 tons all the way up to 1,650 tons.
“Those machines can make extremely large parts,” Reynolds says, “such as gearing for Caterpillar tractors, combines, larger machinery and everything in between. At first, the automotive industry was making the bulk of PM parts, but as the process’s popularity grew, it slowly branched into a wide range of applications and industries, including aerospace, lawn and garden, and heavy equipment as well as EV battery manufacturing. Customers today are also using all-hydraulic machines to make lithium batteries for electric vehicles and beyond.”
