1. The hydraulic press is easy to obtain the maximum pressure
Since the hydraulic press adopts hydraulic transmission and static pressure, the power equipment can be arranged separately, and multiple cylinders can work together, so a large tonnage hydraulic press can be manufactured. The crank press is limited by the strength of the crank connecting rod, so it should not be made very large.
2. The hydraulic press is easy to obtain a large working stroke
Hydraulic presses can easily obtain a large working stroke and can exert full pressure at any position of the stroke. Its nominal pressure is stroke independent and can be stopped and returned anywhere in the stroke. In this way, it is very convenient for processes that require a long working stroke (such as deep drawing), as well as installation of molds, preloading, sub-loading or troubleshooting.
3. The hydraulic press is easy to get a large working space
Because it does not have a huge mechanical transmission mechanism, and the working cylinders can be arranged arbitrarily, the working space is large, which is convenient for organizing automated production lines.
4. The pressure and speed of the hydraulic press can be adjusted steplessly
The pressure and speed can be easily adjusted steplessly in a wide range, and the general three-cylinder hydraulic function can easily obtain three different pressures. If the high-pressure liquid is passed into the middle working cylinder, the primary pressure will be obtained; if the working cylinders on both sides are passed into the working cylinder, the secondary pressure will be obtained; the high-pressure liquid will be fed into the three working cylinders at the same time, and the full pressure will be obtained. And according to the process requirements, it can be used for a long time in a certain stroke. Since the hydraulic pressure can be reliably controlled, overloading can be reliably prevented. In addition, it is also easy to adjust the speed, such as slow speed to avoid impact and so on.
5. Standardization of hydraulic components of hydraulic presses
Hydraulic components have been applied, standardized and serialized, which brings convenience to the design and manufacture of hydraulic presses, and the hydraulic operation is convenient for remote control and automation.
There are many advantages of hydraulic press, but there are also some disadvantages. The main problems that still exist are as follows.
①Because high-pressure liquid is used as the working medium (mechanical oil or emulsion), the precision of hydraulic components is relatively high, the structure is relatively complex, the adjustment and maintenance of the machine is difficult, and the current leakage problem of liquid is unavoidable, which not only pollutes the work environment, waste of pressurized oil, and a fire hazard when applied in hot work fields.
② There is a pressure loss in the liquid flow, so the efficiency is low. The efficiency is especially low during high-speed movement, so the fast and small hydraulic press is not as simple and flexible as the crank press.
Because the hydraulic press has many advantages, it is widely used in industrial production. Especially in the application of forging and stamping production, it has a long history, and it has more advantages for large hot forging and large deep drawing.
With the rapid development of the plastics industry, it has occupied a very important position in the plastic molding process. It is the main pressing and molding machine for processing thermosetting plastics, rubber products and tetrafluoroethylene cold blanks, etc., and can process long glass fibers and flakes. The physical and mechanical properties of the filler thermoisotropic plastics are better than those of injection molded products.
