Hydraulic press is a kind of pressure processing equipment using hydraulic transmission technology, which can be used to complete various forging and pressure forming processes. For example, forging of steel, forming of metal structural parts, pressing of plastic and rubber products, etc. Hydraulic press is one of the earliest machines that used hydraulic transmission. At present, hydraulic transmission has become the main transmission form of pressure processing machinery. In heavy machinery manufacturing industry, aviation industry, plastics and non-ferrous metal processing industry, hydraulic press has become an important equipment.
The hydraulic transmission system of hydraulic press is mainly based on pressure transformation, with high system pressure, large flow and large power. Therefore, special attention should be paid to improving the power utilization rate of the prime mover and preventing shock and vibration during pressure relief to ensure safety and reliability.
According to the pressing process requirements, the main cylinder of the hydraulic press can complete the basic working cycle of fast descending, deceleration pressing, pressure holding delay, pressure relief return and stop (at any position), and the pressure, speed and pressure holding time must be adjustable. Ejection Hydraulic cylinder It is mainly used to eject the workpiece. It is required to realize the action of ejecting, returning and stopping. For example, when the sheet is stretched, the jacking hydraulic cylinder is required to rise, stop, pressure return and other auxiliary actions. Sometimes it is also necessary to use the blank holder cylinder to press the blank tightly to prevent peripheral wrinkling.
The main specification of the hydraulic press is the possible output pressure (tonnage) of the main actuator (master cylinder) in the main movement, which has been serialized. The tonnage of the ejector cylinder is usually 20% - 50% of the tonnage of the main cylinder. The ejector cylinder of the extruder can be about 10% of the main tonnage. The tonnage of the blank holder cylinder of the double action stretching hydraulic press is generally about 60% of the tonnage of the stretching cylinder.
The speed of the master cylinder is determined according to the requirements of the pressure processing process. Generally, the speed of the master cylinder is determined when the oil is directly supplied by the pump Hydraulic system The working stroke speed is not more than 50mm/s, and the fast forward speed is not more than 300mm/s. The fast backward speed of the hydraulic press is equal to the fast forward speed.
