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Press BrakesPress brakes are used to make bends or folds in sheet metal by pressing them into dies by a cold working process. They are either manual, which are only used on thin, formable metal or hydraulic, which are by far the most widely used because they are able to handle tough industrial production jobs. Many are CNC (computer numerically controlled) and fully automated—the operator only keys in machine coordinates and positions the axis accordingly. The traditional press brake machines are vertical, but the horizontal types are able to form long or narrow pieces of sheet metal that are usually difficult to bend. Press brake machines are mostly used in the automotive and aerospace industries, and in any application that uses metal housings or cabinets. In comparison to mechanical press brakes, hydraulic presses are becoming more popular where steady pressure is needed. They are composed of 3 main parts—a pump, an actuator and control valves, and use highly energized hydraulic fluid, which runs through the different components to transfer energy, lubricate and remove contaminants. The hydraulic pump produces the power that the fluid distributes. It is much more powerful than any electric motor, and is considered the generator of the whole system. The actuator carries out the actual metal pressing operation. Here, a cylinder, which is considered the motor, transmits energy to a piston, which carries out the pressing process. The control valves direct the energized fluid to the correct place and control the amount that is released. Often, a press brake contains more than one actuator and the control valves must distribute the fluid evenly between them.
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