Hydraulic press is a machine that uses liquid as the working medium to transfer energy and achieve various processes. Hydraulic presses are not only used for forging and forming, but also for straightening, pressing, packaging, pressing blocks, and pressure plates. Hydraulic press includes hydraulic press and hydraulic press. A water press is called a machine that uses water-based liquids as the working medium, and an oil press is called a machine that uses oil as the working medium. The specifications of hydraulic presses are generally expressed in nominal working force (kilonewtons) or nominal tonnage (tons). Hydraulic presses for forging are mostly hydraulic presses with higher tonnage. To reduce equipment size, large forging water presses often use higher pressure (around 35 megapascals), and sometimes ultra-high pressure above 100 megapascals is also used. Hydraulic presses for other purposes generally use a working pressure of 6-25 megapascals. The tonnage of hydraulic presses is lower than that of hydraulic presses.