Small but strong
- Created: 2017-02-07
They might be compact, but the available options for these press brakes are big
by Larry Adams, senior editor
The small press brake. Compact and fast. Moveable by forklift when needed and capable of bending small, complex parts as well as some larger sized parts, if need be. Electric or hydraulic driven or a hybrid system. Manual or robot fed. Automatic toolchangers, lasers for precision bending, superior ergonomic options, intuitive controllers. Today's models come in multiple formats with a plethora of options.
At Fabtech 2016, many small press brakes were showcased, and most featured electric- or servo-driven technology. For bending small parts, says Scott Ottens, product manager, Amada America Inc., the industry is moving away from traditional hydraulic systems because of speed. Electric press brakes are typically faster for small parts.
Acceleration and speed potential are the biggest advantages of electric-drive technology, agrees Tom Bailey, Trumpf Inc.'s TruBend product manager. “The larger the part, the less benefit you will see from a fast press brake because the weight and handling of the part becomes the real bottleneck. Based on that, the size of the components required in production tends to lead an equipment buyer toward electric- or hydraulic-drive brakes.”
Speed is also important in production situations where the press brake supports other processes. “Higher stroke rates allow press brakes to be more in line with the upstream process machines, such as the laser or the punching machine,” says Tony Marzullo, press brake development manager for LVD Strippit.
For those companies searching for a press brake, especially to produce smaller and complex parts, FAB Shop Magazine Direct showcases a range of equipment to address those needs.
High-speed press brake
The EG 6013 press brake from Amada is an ultra-high precision, high-speed compact brake that features an advanced dual-servo power drive system for fast approach, bending and return speeds. The power drive contains two AC servomotors that include a 2.9-kW motor for bending and a 1.3-kW motor for approach and return.
“We use the high speed for very fast approach and return, and then we have a larger high-torque motor that kicks in when the machine goes into bending that can generate more force,” Ottens says. “We can get 66 tons out of our 1.3-kW motor.”
Other features include a 5-axis L-Shift back gauge, which speeds setup for complex parts. High-speed movement ensures that the gauge fingers are positioned as quickly as the operator positions the part. The unit also features automatic angle measuring, offline programming, multiple part load/unload stations and an automatic toolchanger.
Amada also offers the EG 6013 AR, a robotic version of the 6013 with the power and precision of a servo electric press brake with an advanced bending robot engineered for unmanned production of any lot size or part mix.
The back gauge of the EG 6013 AR is equipped with tactile sensors that detect the position of the part in the X and Y directions prior to bending and initiate corrective measures if the sensors detect that tolerances have drifted.
Several unloading options are also available. Completed parts can be stacked by the robot, placed in boxes or on a synchronized conveyor belt. The robot can change bending tools and grippers automatically and handle workpieces throughout the entire process.
The expert press brake
The Xpert 40 press brake from Bystronic Inc. is a 40-ton unit that offers two new options: an optional bending line laser for bending a part without using the back gauge and an optical foot switch that increases speed and improves ergonomics.
Paul LeTang, product manager of press brake/tooling at Bystronic, says it’s not always possible to position parts on the Xpert 40 using the back gauge. One example would be a conical part because that shape doesn’t provide a stop position. By projecting the optional bending line laser directly onto the surface of the part, the operator can position and bend the part without a back gauge.
For parts that can be bent with the back gauge system, the Xpert 40 features up to six axes that enable the production of highly complex shapes.
“The 6-axis back gauge has the ability to 'capture' the part,” LeTang says. “This capture feature allows for processing more complicated shapes by not only ensuring the gauge locations are correct in the typical X direction, but they ensure the gauge locations are correct in the Z and R directions, as well.”
The optical foot switch allows operators to trigger the stroke of the brake through foot movement, which increases the machine’s ergonomics by eliminating the need for a manual foot switch.
“The Xpert 40’s bend-per-hour rate can be double that of a conventional hydraulic press brake,” he explains. “Instead of pressing and holding a mechanical foot pedal thousands of times per day, the operator only has to break a light beam with the tip of his toe to initiate the cycle.”
This also increases processing speed. In terms of bends per hour (bph), a typical press brake can reach 622 bph, and a typical high dynamic electric or hybrid brake can reach 916 bph. The Xpert 40 is rated to reach 1,028 bph.
“The individual part cycle time is reduced mainly by increasing the acceleration rate of the ram and back gauge,” LeTang explains. “However, production times are highly dependent on the machine operator. In fact, only about 25 percent of the production time is actual bending time. The bph on the Xpert 40 is predominately increased by addressing the operator work area with an integrated tooling magazine, work table and inspection station.”
Go for it
Cincinnati Inc. offers the GoForm compact electric press brake designed to bend simple and complex parts up to 1/4 in. thick and less than 50 lbs. Like others on the market, one of its strengths is its ability to be used where needed.
“At just over 6,000 lbs., the GoForm is easily moved and quickly put into production without being bolted to the floor,” says Todd Kirchoff, product manager. “This provides fabricators with on-demand metalforming along with the flexibility to make changes to shop floor configurations. With floor space at a premium, the ability to quickly respond to changing workflow, special orders or tight production schedules can be a clear competitive advantage.”
According to the company, the GoForm is built to meet the rigorous demands of multi-shift operations, featuring a large touchscreen control, PC-based 3-D graphics and bending simulation that guides the operator though complex setups and part handling sequences.
“Another unique characteristic of the GoForm is its 10-in. stroke and 17-in. open height for jobs requiring tall tools and adapters,” says Matt Garbarino, director of marketing communications. “I believe this is the longest stroke on any electric press brake of this size, which allows for more versatility on the types of parts to form and the tooling that can be used.”
He adds that the machine can accommodate American- or European-style tooling.
Other features include a 6-axis back gauge with flip-up gauge fingers and high-resolution incremental encoders for ram repeatability. The long ram guides and low friction slide liners produce smooth ram motion with minimal maintenance. Wedge height adjustments in the die holder provide a simple method to maintain bed-to-ram parallelism to form consistent bend angles in long parts.
New electric press brakes
JMT USA now offers hydraulic and electric 4-ft. press brakes. The standard hydraulic model is the JMT ADR 1260, a 66-ton brake that has 15.75 in. of open height, 6.3-in. stroke and throat depth of 13.75 in. Standard features include sliding sheet supports, a box clamp system, separate Y1 and Y2 axes, and an X-axis back gauge and controller.
New features include a control arm that swivels to allow operators to work closer to the part and a safety laser to keep the operator safe when doing so.
Last year, JMT entered the electric press brake market with the Eco Bend 2512, a servo-driven brake that consumes 40 percent less power than a conventional brake of equal size. Because of the servo drives, the movement of the brake is considerably faster in all directions while maintaining ±0.0004 accuracy and repeatability.
This year, JMT upgraded the model to the Eco Bend 3515, which is about a foot larger than the 2512 (4 ft. 11 in. compared to 3 ft. 11 in.).
Dynamite press brake
LVD Strippit expanded its Dyna-Press series of compact, high-speed electric press brakes with the Dyna-Press 40/15 Plus, a 40-ton model that offers a working length of 60 in. The new machine joins a roster of small machines, including 12-ton and 24-ton versions introduced last year.
Like other Dyna-Press models, the new Dyna-Press 40/15 Plus efficiently bends parts at speeds of 59 ipm, producing more parts per hour at a lower cost, Marzullo says. The coupling of the ram and servomotors is realized through two heavy-duty ballscrews to distribute force and tonnage evenly across the working length. The electric ram offers smooth transition from approach to working speed and minimizes power consumption through the use of an optimal power-to-inertia motor ratio.
In addition to the fast-acting ram and higher bending force, the newest Dyna-Press provides impressive production capabilities with consistent repeatability, accuracy and flexibility to handle a broader range of parts through its precision 4-axis back gauge.
True press brake
Trumpf’s TruBend Series 7000 precision press brakes are compact machines for bending parts up to 40 in.
According to Bailey, the 7036 model is the world’s most ergonomic press brake. Optimum working conditions and user-friendly operating elements are integrated into the machine. Gas spring supported pedals allow the height and angle of the foot rests to be adjusted. The arm support is also adjustable, enabling operators to set the workpiece to individual preferences.
In addition, the monitor for the TA6000 control system of the TruBend Series 7000 can be adjusted electronically and set to the appropriate angle. Optional Trumpf LED lighting illuminates the area in front of and behind the beam, ensuring correct lighting conditions at the bend, without heat radiation. An optional laser diode also projects the bend line onto the surface of the sheet metal, simplifying the accuracy of guiding the workpiece into the back gauge.