While everyone continues to discuss ways to increase the number of skilled workers in the United States, press brake manufacturers are taking practical steps to reduce reliance on manual labor and also increase the value of that labor.
To address the issue, MC Machinery Systems Inc. is offering an all-new automatic tool changer for press brakes. Using an ATC reduces the skill level required to run a press brake and increases the efficiency of the operators by reducing setup times. Operators have time for other duties while the ATC is loading up the tools in the press brake and getting ready to run the job.
In addition to efficiency, the ATC allows for accuracy and consistency. Some programs require tight tolerances, with the tools placed within 0.005 in. of the location where the program has them. An operator may be off by an 1/8 in. or even a 1/4 in. The ATC might be the difference between a 3-min. or less setup and a 20-min. setup where the operator is trying to make the correct adjustments.
In developing its new TC32 ATC, MC Machinery took its time reviewing the positives and negatives of what was available, and learning from customers the features and benefits they were most interested in.
“One thing we discovered was every tool changer is fixed for a certain material range,” says David Bray, national press brake product manager, MC Machinery. “You can only use the tools that are in the tool changer and it is relatively complicated to change those tools. You aren’t changing them out on a weekly or monthly basis. When you order the tool changer, whatever the capacity of that changer, you are limited to the tools you have in there.
“If you put it on a 3-m press brake and you only put 26 m of tools in the machine, typically two or three punches and three or four dies, you are limited once you put the tools in,” he continues. “You can only bend 22 through 16 gauge on one tool changer, then you have to have another tool changer for 16 to 14 gauge. It is very limited that way and that is standard across the industry. You are limited to the tools that are inside the tool changer.”
This is one of the main issues MC Machinery’s new ATC addresses. The ATC can go 32 m with standard tool storage and an optional 52 m for tool storage, which is large for the market.
“In addition,” Bray says, “if there are tools that won’t go into the tool storage – they are used infrequently or they are heavy or have a large radius, say a 3-in. V opening, for example – you can still create that program offline or through the control, send the program to the machine and the operator can still use the press brake like any other standalone press brake without using the tool changer associated with it. When the brake is done with the tools, the operator can take those tools out and the brake will change tools just as it would for any high-run part. The tools don’t have to be in the storage for the press brake to be used.”
This provides the flexibility to use the ATC or use the machine as a standalone press brake.
Another feature customers showed interest in, and MC Machinery added, was a cleaning tool. Instead of operators performing tool cleaning as a secondary operation, the TC32 features a cleaning system that cleans the tools and the surface of the bed. When it is changing tools, the ATC automatically cleans the tool before loading it and before putting it back into the storage. As tools are moving in and out, the system removes debris and dust from the surface.
“It is done in the same process,” Bray says. “It is not a secondary operation that operators have to remember to do. It’s automatically done. We decided as a manufacturer to eliminate certain processes from the operator and just build them in as standard.”
MC Machinery’s current BH Series Dual Drive hybrid press brakes are premachined to accept the new ATC. The press brake can be ordered as a package from the factory with the ATC attached. But the company wanted to offer options so the machine can grow with its customers. Customers can buy a standalone press brake and then if parts change or they are having trouble finding qualified people to set up the brake, they can invest in automation by adding an ATC.
Another way MC Machinery simplifies press brake operations is with the Videre system, which will be displayed with the new ATC at the Fabtech 2019 show. The Videre system supports the operator by clearly displaying functional process information that is easy to understand. The setup and work handling that once required a skilled operator is streamlined. Support information from setup to processing is displayed in real time, real size and real location.
“This augmented reality system displays the control info, such as the tooling, the bend sequence and the 3-D part, on the front of the machine,” Bray says. “It allows the operator to see factors like how the part is being presented, the setup and how to orient the part. If you have an operator that has never run a press brake, it can teach the operator how to bend the customer’s parts in real time at the machine.”
Along with Videre, the ATC will also be shown with the BH13530 Dual Drive hybrid press brake at Fabtech 2019. This brake has unique features of its own to produce parts faster at a lower cost. The BH Dual Drive system controls high-speed up and down movement with a ballscrew and controls bending with the servo-hydraulic piston.
“The press brake uses a ballscrew for the fast descent and fast ascent and uses the hybrid system for the bending,” Bray says. “The advantages are accuracy and speed. Everybody in the industry talks about inches per minute or millimeters per second, but nobody ever talks about what distance they need to travel before they reach that speed. Because of the electrical ballscrew for the fast descent and ascent, you’re instantaneously at full torque and full speed as soon as you hit the foot peddle.
“A lot of our competitors’ press brakes have to travel a certain distance to reach the maximum speed listed because they use an hydraulic, hybrid or pulley drive system,” he continues. “So even if the brake appears to be the same or faster millimeters per second on the spreadsheet, we’re getting up to twice as many strokes per minute because it doesn’t matter where you are in the stroke, you’re always going to be faster than its counterpart. And for customers that decrease that stroke, it’s even worse because you’re not reaching a maximum speed on those machines because you decrease the stroke below the minimum needed to reach that speed.”
Along with speed and accuracy, the Dual Drive system offers energy savings thanks to an assist device that stores the energy of down movement and returns it during up movement.
“Another unique feature in our Dual Drive system is that as the hybrid system engages and comes down and bends the material, there is an accumulative effect,” Bray says. “It captures that energy inside the accumulator as it is bending and when the machine returns, the accumulator releases the energy that was stored and helps the ballscrew pull the ram back up. All of the energy spent bending is actually captured and returned back into the machine.”
Lastly, a fourth benefit of the Dual Drive system is increasing the life of the hydraulic components 66 percent.
“I spent about 20 years in service and maintenance, and the typical hydraulic/hybrid systems in the United States had about a 10-year lifecycle average, considering all the valves, seals, pistons, pumps and other hydraulic components in the system. If you increase that life by 66 percent, the life of a hydraulic component becomes 16 or 17 years.”