Blog

Four-column hydraulic presses, also known as hydraulic presses, are machines that utilize Pascal's law to transmit liquid pressure. They come in many varieties and have diverse applications. They can be categorized into hydraulic presses and water presses based on the type of liquid used for pressure transmission.

1. Equipment Overview

Four-column hydraulic presses, also known as hydraulic presses, are machines that utilize Pascal's law to transmit liquid pressure. They come in many varieties and have diverse applications. They can be categorized into hydraulic presses and water presses based on the type of liquid used for pressure transmission. Water presses generate higher overall pressure and are often used in forging and stamping. Forging water presses are further divided into die forging water presses and free forging water presses. Die forging water presses use dies, while free forging water presses do not. The first 10,000-ton water press manufactured in China was a free forging water press. A four-column hydraulic press consists of two main parts: the main body and the control mechanism. The main body of the hydraulic press includes the hydraulic cylinder, crossbeam, columns, and filling device. The power mechanism consists of an oil tank, high-pressure pump, control system, electric motor, pressure valve, directional valve, etc. This hydraulic press is suitable for the pressing process of plastic materials, such as powder product molding, plastic product molding, cold (hot) extrusion metal molding, sheet metal stretching, and processes such as transverse pressing, bending, flipping, and correction. The four-column hydraulic press has an independent power mechanism and electrical system, uses centralized button control, and can achieve three operating modes: adjustment, manual, and semi-automatic.

Four-column hydraulic press equipment has the following characteristics:

1. Reduced weight and material savings. For typical parts such as automotive engine mounts and radiator brackets, hydraulically formed parts are 20% to 40% lighter than stamped parts. For hollow stepped shaft parts, the weight can be reduced by 40%.
 
2. Reduced number of parts and molds, lowering mold costs. Hydraulically formed parts usually only require one set of molds, while stamped parts often require multiple sets of molds. The number of parts for engine mounts formed by hydraulic pressing is reduced from 6 to 1, and the number of parts for radiator brackets is reduced from 17 to 10.
 
3. Reduced subsequent machining and welding in assembly. Taking radiator brackets as an example, the heat dissipation area is increased by 43%, the number of welds is reduced from 174 to 20, the number of processes is reduced from 13 to 6, and productivity is increased by 66%.
 
4. Improved strength and stiffness, especially fatigue strength. For example, the stiffness of hydraulically formed radiator brackets can be increased by 39% in the vertical direction and 50% in the horizontal direction.
 
5. Lower production costs. According to statistical analysis of hydraulically formed parts that have been applied, the production cost of hydraulically formed parts is on average 15% to 20% lower than that of stamped parts, and the mold cost is reduced by 20% to 30%.

The hydraulic transmission system of a four-column hydraulic press consists of a power mechanism, a control mechanism, an actuator, an auxiliary mechanism, and a working medium. The power mechanism usually uses an oil pump as the power source, generally an accumulator oil pump. To meet the requirements of the actuator's movement speed, one or more oil pumps are selected. Low-pressure (oil pressure less than 2.5MP) uses gear pumps; medium-pressure (oil pressure less than 6.3MP) uses vane pumps; high-pressure (oil pressure less than 32.0MP) uses plunger pumps. It is used for pressure processing and forming of various plastic materials, such as extrusion, bending, and stretching of stainless steel and steel plates, and cold pressing of metal parts. It can also be used for pressing powder products, grinding wheels, resin-bonded wood, and thermosetting resin products.