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According to the requirements of the pressing process, the hydraulic press’ main cylinder is capable of carrying out a basic working cycle that includes rapid downward movement, reduced-speed pressing, pressure retention for a specified period, pressure release during the return stroke, and stopping (at any position). Additionally, the pressure, speed, and pressure retention time must be adjustable. The ejection hydraulic cylinder is primarily used to eject workpieces, and it is required to be capable of performing ejection, retraction, and stop actions. For example, when stretching thin sheets, auxiliary actions such as the lifting, stopping, and pressure return of the ejection hydraulic cylinder are also required. Sometimes, a blank holder is also needed to press the blank tightly in order to prevent wrinkling at the edges. Hydraulic presses are specified by the maximum pressure (tonnage) that the main actuator (main cylinder) can generate during the main motion, and they are available in various series. The tonnage of the ejector cylinder is usually 20% to 50% of the tonnage of the main cylinder. The ejector cylinder of the extruder can be approximately 10% of the main tonnage. The tonnage of the blank holder cylinder in a double-acting stretching hydraulic press is generally around 60% of the tonnage of the stretching cylinder. The speed of the main cylinder is determined by the requirements of the pressure processing process. In hydraulic systems powered directly by pumps, the speed during the working stroke does not exceed 50 mm/s, the speed during fast forward movement does not exceed 300 mm/s, and the speed during fast reverse movement is equal to that during fast forward movement.