Structure Of Hydraulic Press

driving system
The driving systems of hydraulic presses mainly have two types: pump direct drive and pump accumulator drive. The pump directly drives the pump of this driving system to provide high-pressure working fluid to the hydraulic cylinder. The distribution valve is used to change the direction of the liquid supply, and the relief valve is used to adjust the limited pressure of the system, while also playing a safety overflow role. This driving system has fewer links, a simple structure, and the pressure can automatically increase or decrease according to the required working force, reducing electrical energy consumption. However, the capacity of the pump and its driving motor must be determined by the maximum working force and maximum working speed of the hydraulic press. This type of drive system is commonly used for small and medium-sized hydraulic presses, as well as large (such as 120000 kN) free forging hydraulic presses directly driven by pumps.
Pump accumulator drive In this drive system, there is one or a set of accumulators. When there is a surplus of high-pressure working fluid supplied by the pump, it is stored by the accumulator; When the supply is insufficient to meet the demand, it is replenished by the accumulator. By using this system, the capacity of the pump and motor can be selected based on the average amount of high-pressure working fluid, but because the pressure of the working fluid is constant, the energy consumption is large, and the system has multiple links and a complex structure. This type of drive system is often used for large hydraulic presses, or to drive several hydraulic presses with a set of drive systems.
structural style
According to the direction of the applied force, hydraulic presses can be classified into two types: vertical and horizontal. Most hydraulic presses are vertical, while hydraulic presses for extrusion are mostly horizontal. According to structural types, hydraulic presses can be divided into double column, four column, eight column, welded frame, and multi-layer steel strip winding frame types. Medium and small vertical hydraulic presses also use C-frame type. The C-type frame hydraulic press has three open sides, making it easy to operate but with poor rigidity. The welding frame hydraulic press used for stamping has good rigidity, with the front and back open but the left and right closed. In a vertical four column free forging hydraulic press, the oil cylinder is fixed in the upper beam, and the plunger is rigidly connected to the movable crossbeam. The movable crossbeam is guided by the column and moves up and down under the pressure of the working fluid. There is a workbench on the crossbeam that can move back and forth. Install upper and lower anvils under the movable crossbeam and on the workbench, respectively. The working force is borne by a frame composed of upper and lower crossbeams and columns. Large and medium-sized free forging hydraulic presses driven by pumps and accumulators often use three working cylinders to obtain three-stage working force. There are also balancing cylinders and return cylinders that apply upward force outside the working cylinder.