Hydraulic system requirements and analysis of hydraulic press

The hydraulic press is a device that uses hydraulic transmission technology for pressure processing; it can be used to complete various forging and press forming processes, such as forging of steel; forming of metal structural parts; restrictions on plastic products and rubber products. Hydraulic presses are the first to use hydraulic pressure. One of the transmission machinery; the current hydraulic transmission has become the primary transmission method of pressure processing machinery. In the heavy machinery manufacturing industry, aviation industry, plastics and non-ferrous metal processing industry, etc.; hydraulic machine has become an important equipment.The hydraulic transmission system of the hydraulic machine is mainly based on pressure change; the system pressure is high; the flow rate is large; the power is large. Therefore, special attention should be paid to improving the power usage rate of the prime mover and avoiding shock and oscillation when the pressure is released; ensuring safety and reliability.

The hydraulic machine can complete the basic operation cycle of the deceleration limit, the pressure-preserving delay, the pressure-relief return, and the stop-and-stop (independent position) according to the limitation of the process demand. The pressure, speed and pressure holding time need to be able to be conditioned. It is mainly used to eject the workpiece; the demand can complete the action of ejecting, retreating, and suspending. For example, when the thin plate is stretched, it also needs to take out the hydraulic cylinder ascending, suspending and pressure returning, etc. Sometimes it is necessary to use the crimping cylinder to make the blank. Pressing; to avoid wrinkling around. The hydraulic machine uses the maximum pressure (tonnage) that can be output by the primary actuator (master cylinder) in the main motion as the primary standard for hydraulic presses; and has been serialized. The tonnage of the top tank is often selected from the tonnage of the master cylinder. 20% to 50%. The ejector cylinder of the extruder can be used with about 10% of the primary tonnage. The tonnage of the pressure cylinder of the double-action stretching hydraulic press; usually about 60% of the tonnage of the drawing cylinder. Determine the speed of the master cylinder; usually in the hydraulic system directly supplied by the pump; its working stroke speed does not exceed 50mm / s; fast forward speed does not exceed 300mm / s; fast retreat speed and fast forward speed is flat.