The hydraulic transmission system of Four column hydraulic press is composed of a power mechanism, a control mechanism, an actuator, an auxiliary mechanism, and a working medium. The power mechanism usually uses the oil pump as the power mechanism, which is generally the product oil pump. In order to meet the requirements of the movement speed of the actuator, one oil pump or more oil pumps are selected. Low pressure (oil pressure is less than 2.5MP) with gear pump; Medium pressure (oil pressure less than 6.3MP) with vane pump; High pressure (oil pressure less than 32.0MP) with plunger pump. The pressure processing and forming of various plastic materials, such as the extrusion, bending, stretching of stainless steel plate and cold pressing of metal parts, can also be used for powder products, grinding wheels, bakelite, resin thermosetting products.