Capital equipment is rarely an impulse purchase. No one acquires a major machine based on their mood or because it “just felt right.” Capital equipment investments are typically driven by a mix of operational, financial and strategic goals – significant financial commitments that require thoughtful decision-making.
“For a shop that runs 10 parts in 20,000 runs several times a year, automating a press brake is a no-brainer,” says Dave Cotton, senior business development manager at BLM GROUP USA. “But most shops don’t operate that way anymore. It seems difficult to justify putting 10, 20, 30 parts at a time on an automated system.”
Historically, high-mix, low-volume press brake operations were perhaps the most difficult automation investment to justify. But things have changed.
Thanks to modern offline programming, automatic tool changing and intelligent material analysis, robotic bending cells aren’t just for high-volume shops. With turnkey systems like BLM’s ProBend HBS II, fabricators with ever-changing part runs can achieve unattended, highly flexible bending operations, and they can justify the equipment investment to do it.
Cell insight
There are plenty of reasons that should compel a fabricator to invest in automation. Businesses are practically being forced into it. They need higher throughput in the midst of low staffing. Customers want higher quality at lower costs. And, if a fabricator wants new customers, they need to expand their capacity and their capabilities. Understanding this, BLM GROUP launched the HBS II, a fully enclosed, all-electric turnkey bending cell outfitted with a 6-axis Fanuc robot and an E-Series 205-60 direct-drive ProBend press brake.
“The idea behind the HBS II system is to take on as many tasks as it possibly can in one footprint,” says Robert Jackson, applications engineer for ProBend systems at BLM GROUP USA. “Part loading and unloading is handled internally by the system, so the operator doesn’t have to interrupt the process in any way. With its extensive load/unload capabilities, production runs uninterrupted.”
From a high level, the system delivers on the benefits the industry expects from automation: It can run more parts with higher quality and consistency, which allows operators to focus on other, more complex tasks.
“Some folks think an operator can run faster than the robot, and that could be true,” Cotton says, “but this system has two different loading areas, which allows the cell to run for hours uninterrupted on one side while the operator reloads parts on the other side.
“At the end of the day, what matters is how many parts are on the pallet,” he adds. “Considering the robot doesn’t take any breaks or get fatigued, you end up with more parts on that pallet and with higher consistency.”
The system’s two loading bays can either be skid-based or cart-based and can be divided into 12 independent load boxes between the two bays. Each of the boxes can be stacked with parts for multiple runs of different jobs, which also allows customers to set it up to run kits.
“Job shops are constantly changing their production mixes,” Jackson says. “With the system, they can be running a multi-hour project but then quickly change over to one of those hot jobs that unexpectedly shows up in the middle of the day. Because one load bay is isolated, without interrupting machine performance, you can load whatever parts you need and reposition it. Then, it’s simply a matter of adding the next part into your schedule. It’s simple to accommodate this type of emergency work.”
Tackling variables
Jackson says the HBS II is a culmination of industry advancements and BLM GROUP know-how. “The press brake world has done a phenomenal job of figuring out the important variables behind successful operating,” he says, “whether it’s variables about materials, operators or the machine itself.”
He points to common system components like its sheet support system that prevents the material from bowing under its own weight. Meanwhile, the Iris Plus technology fights another pesky variable: material variation. Experienced fabricators know that when a material provider says something is 16 gauge, that isn’t always exactly the case.
“Iris Plus is an advanced real-time angle measuring system that, essentially, is learning about the material as it actively bends it,” Jackson explains. “It tackles grain direction, which greatly affects bending, which traditionally was something the operator had to account for.”
It also accounts for springback – another complicated aspect of press brake bending that operators traditionally deal with. The system bends the part about 90 percent of the way and then relaxes a little to calculate the springback of the material for that specific bend, which then gets fed into an internal database for later retrieval.
“Let’s say we’re dealing with a rectangular pan that has a couple long legs and a couple short legs,” Jackson says. “When the press brake operator gets a stack of what looks like clean parts that are exactly the same, the reality is that there potentially will be some grain variation, which will vary their bends. The operator cannot know for sure either way.
“But, with the Iris Plus system, it won’t matter because the system is looking at each bend and will test it every time, isolate the springback and direct the system to output the bend,” he says. “Even if the material grain is the same, the thickness might not be exactly the same from supplier A to supplier B. There are all kinds of variables that exist within the material.”
Squaring up the material is another variable that must be addressed in automated processes. Within the HBS II, the robot relies on a couple of components that Jackson notes “exist in the background.”
“One of those components is the backgauge that the robot touches off of to ensure the bend line is correct,” he says. “The HBS systems are sensorized, so if one side of the material touches and triggers the sensor, but the other doesn’t, the robot knows to reposition the part to find the sensor, ensuring the bend is square before engaging the bending system.”
Power of programming
One of the most critical components of the cell, perhaps, is the way in which a part is programmed. Programming is yet another of the important variables behind successful operation, which BLM GROUP tackled by adding an offline simulation suite. The software comes as a standard part of the overall HBS II robotic cell package.
The ease with which a part can be programmed will, of course, depend on the complexity of the part – the more bends a part has, the more time it takes to program it – but there is more to the process than just programming a part’s bends. A program must also include the loading and unloading of the part, how to pick it off of the aligner and present it to the machine, and then, finally, how to stack it.
The software programs the cell and press brake to pick from the aligner table, handle the part through production and palletize everything. Additionally, it informs the onboard project supervisor program which tools to load into the machine and where. The 3-axis loading system and the tool library (positions on the machine as well as in storage) are controlled by the supervisor program. There is also a teach pendant available for fine adjustments, if necessary.
“The software relies on the specs for each specific cell and robot to determine the best trajectory the robot should take to get from point A to point B,” Jackson says. “The system’s digital space has been set to match the exact parameters of its physical space. It understands what it can and can’t do and uses safety boundaries to avoid crashes.”
Jackson adds that tool changes are also something that can’t be underestimated in the overall efficiency of the system’s programming. As with bend verifications, tool changes are another thing that operators no longer have to think about.
“Tool changes are all pre-programmed, so operators don’t have to deal with it – even during offline programming,” Jackson says. “They’re controlled by the main brain in the cell. It understands where the tools physically live in its library in the machine and can build each tooling layout independently.”
In addition to the programming software, each HBS II cell comes standard with three end-of-arm tools: a gripper for small parts that has a suction cup and a physical gripper and a larger model that has suction cups, a physical gripper and magnets. The system also has a third end-of-arm tool that acts as the tool change arm, which engages a series of safety tabs to pull tooling in and out.
If needed, the system can expand to house up to four or five grippers that can all easily be changed out. Jackson explains that the software simply needs to be told which grippers are available.
“We already loaded a library of standardized end-of-arm tools that are available, but we can also make customized tools for niche applications,” he says. “It’s a system we’re continually building on.”
Making the case
At its core, the HBS II is an incredibly flexible tool. With its intuitive offline programming, automatic tool changing and intelligent material analysis, fabricators can efficiently manage high-mix, low-volume bending operations, helping to justify the investment and achieve a quick ROI. Jackson reminds customers, however, that ROI will look a little different for each fabricator.
“ROI is achieved in the persistence of the machine continually running,” Cotton says, “but it can be based on the consistency of your parts just as much as it can be based on the flexibility of your workforce. In the end, every customer is different. A job shop looks at it one way while an OEM might look at it in an entirely different way. And sometimes, it might just depend on how bad the customer wants it.”
Cotton further explains, Cotton says that there are companies that are OK with the status quo, but there are also customers that are aggressively looking to improve their margins and grow their business.
“The folks who aren’t OK with the status quo will get creative to justify the investment,” he says. “They’ll pull the investment funds from other budgeted areas, which makes a lot of sense. You have to look at all the potential factors, especially the safety factor.”
Inherently, automated processes reduce the chance of employees getting hurt or injured on the job, and the HBS II is no different in that regard. It removes employees from dangerous pinch points and reduces the need for heavy lifting. By focusing on risk-reduction initiatives and safety budgets, the investment is often easier to justify.
“A key component to all of this is the safeguarding of humans and eliminating injuries,” Cotton says. “The safety aspect is one of the larger considerations of a cell like this.”
To help customers better understand the potential ROI, Israel Irenas, product specialist for press brakes, says BLM GROUP sales representatives and product managers will work together to provide the customer with the information they need to make a decision they can be confident with. He concludes saying it’s a service that’s intended to be the first step in a long-running, meaningful partnership.
Whether they’re automated or manual, press brakes are one of the most critical pieces of equipment on a shop floor. To read more articles about bending, check out Techgen Media’s extensive coverage on the topic.
