What are the advantages and disadvantages of hydraulic press?
1 Advantages
For hollow variable cross-section structural parts, the traditional manufacturing process is to press and form two half pieces first, and then weld them into a whole, while hydroforming can form hollow structural parts with variable cross-section along the component at one time. Compared with the stamping welding process, hydroforming technology and process has the following main advantages:
1. Reduce quality and save materials. For typical parts such as automobile engine brackets and radiator brackets, hydroforming parts are 20% ~ 40% less than stamping parts; for hollow stepped shaft parts, the weight can be reduced by 40% ~ 50%.
2. Reduce the number of parts and molds, reduce mold costs. Hydroforming parts usually only need 1 set of mold, and stamping parts mostly need more than one set of mold. The number of hydroformed engine bracket parts was reduced from 6 to 1, and the number of radiator bracket parts was reduced from 17 to 10.
3. The amount of welding for subsequent machining and assembly can be reduced. Take the radiator bracket as an example, the heat dissipation area increased by 43%, the number of solder joints decreased from 174 to 20, the process decreased from 13 to 6, and the productivity increased by 66%.
4. Improve the strength and stiffness, especially the fatigue strength, such as the hydraulic forming of the radiator bracket, the stiffness in the vertical direction can be increased by 39%, the horizontal direction can be increased by 50%.
5. Reduce production costs. According to the statistical analysis of the applied hydroformed parts, the production cost of hydroformed parts is reduced by 15% ~ 20% on average than that of stamping parts, and the mold cost is reduced by 20% ~ 30%.
2. Disadvantages
1) hydraulic components manufacturing precision requirements due to the high technical requirements of the components and assembly is more difficult, the use of maintenance is more stringent.
2) Difficulty in realizing constant ratio transmission Hydraulic transmission uses hydraulic oil as the working medium, and there will inevitably be leakage between the relative moving surfaces, and the oil is not incompressible. Therefore, it is not suitable for use in occasions where the transmission ratio is strict, such as the transmission system of thread and gear processing machines.
3) Oil is affected by temperature. Because the viscosity of oil changes with the change of temperature, it is not suitable to work in high temperature or low temperature environment.
4) Not suitable for long-distance transmission of power due to the use of oil pipe transmission pressure oil, pressure loss is large, it is not suitable for long-distance transmission of power.
5) Mixing air in the oil is easy to affect the working performance. After mixing air in the oil, it is easy to cause crawling, vibration and noise, and the working performance of the system is affected.
6) Oil is easy to pollute. Oil pollution will affect the reliability of the system.
7) Failure is not easy to check and eliminate.
What are the advantages and disadvantages of hydraulic press? What is the hydraulic press used?
Hydraulic press is a kind of machine that uses liquid as the working medium to transfer energy to realize various processes. In addition to the hydraulic press for forging and forming, it can also be used for correction, pressing, packing, pressing block and pressing plate. The hydraulic press includes a hydraulic press and a hydraulic press. The water-based liquid as the working medium is called the hydraulic press, and the oil as the working medium is called the hydraulic press. The specifications of the hydraulic press are generally expressed in nominal working force (kN) or nominal tonnage (tons). Forging hydraulic press is more hydraulic press, higher tonnage. In order to reduce the size of the equipment, large forging hydraulic presses are commonly used for high pressure (about 35 MPa), and sometimes high pressure above 100 MPa is also used. Hydraulic presses for other purposes generally use a working pressure of 6 to 25 MPa. The tonnage of the hydraulic press is lower than that of the hydraulic press.