Press brakes are machines that bend sheet, plate and extruded material. The machine forms predetermined bends by securing the workpiece between a punch and die. The bottom tool “The Die” is positioned onto the table of the machine while the top tool “The Punch” is secured into the upper beam. The machine forces the punch and die together to create a bend in the material.
Press brakes are generally rated by their pressing capacity, their bending length, or machine width. They can be fitted with a wide variety of customized tooling to press the workpiece into the desired form.
There are basically four different types of press brakes.
Mechanical: An electric motor spins a large flywheel at very high speeds. A clutch is then engaged which activates a crankshaft which in turn controls the ram of the machine. The ram forces the punch through the workpiece into the die with a lot of tonnage.
Hydraulic: Hydraulic pressure is applied to two or more synchronized cylinders which activates the ramming process. Depending on the machine, the ram can force the punch downward or the bed with the die can be forced upward. Hydraulics allow for more control of the machine as well as more accuracy for the metal being bent.
Pneumatic: The pneumatic press brake uses compressed air for the bending process. Though they do not offer the extreme pressure that other types of press brake machines provide, they can however provide more speed of use and cleanliness.
Servo-electric: Servo-electric brake presses use servo-motors to drive a ball screw to activate the ram of the machine. This process is a very eco-friendly system that provides high efficiency and precision. These machines can use up to 50% less energy than other types of press brake machines.
One of the main improvements to press brake technology is a device called the back gauge. A back gauge can position a workpiece in the proper position to make an accurate bend in the metal. This is only offered in modern CNC machines to produce an automated adjustable stop for the workpiece. CNC driven press brakes no longer have to rely on tooling to coordinate the bend angle of the piece.
Conclusion
As you have read, press brakes are a vital part of a fabrication facilities capabilities. They come in various pressing capacities and numerous sizes. They also come in four major types of machines that are targeted for different projects and specifications. As for the future, there is no doubt the press brake machine will get more computerized and automated to create a more efficient and eco-friendly fabrication atmosphere.