What is hydraulic press? Actually, it is a kind of machinery that is based on liquid as the working medium and Pascal as the working principle to transfer energy so as to realize different workmanships. Generally speaking, it is made up of three main parts, which are main engine, dynamical system and hydraulic control system. There are many different types of hydraulic pressing machine , such as oil press and hydraulic press according to liquid's pressure, die forging press and open die forging press and so on. Maybe, you are still curious about what the so-called hydraulic press is used for. It is widely used to forge and press, rectify, pack and clamp. Besides, it also asks for some basic requirements for working medium. Firstly, it should have certain liquidity and low compressibility. Then, the medium also needs to have the function of anti-corrosion and better lubricating property. At the same time, its performance should be stable and can work for a long time without metamorphism and it also should be easy to seal. Driving system is another important aspect that should be introduced. As the whole, there are two main types of driving systems, which are pump driving system and pump-accumulator driving system. The former one uses the high-pressure hydraulic fluid that is supplied by pump and the flat valve is used to change the direction of the feed flow, while relief valve is used to adjust the limited pressure of system. Such a kind of driving system has the advantages of less system links and simple structure as well as low power consumption, which is often chosen by small and medium sizeforging hydraulic press. When it comes to the pump-accumulator driving system, it has one or a set of accumulators. Once there is superfluous high-pressure operating fluid, the accumulator will store it, while the accumulator will replenish if the supply is insufficient. Compared with the former one, there are many more links and the inner structure is comparatively more complicated. In addition, I also would like to involve some knowledge about the daily maintenance. In the first place, it had better dead-load operate for five minutes so as to pave the way for proper functioning. The new equipment needs to be filtrated thoroughly, especially the fuel tank. Meanwhile, the oil filter point is forbidden to be opened as the system emits heat during the using process. Most important, it mustn't be used in the open air and should have the rain-proof measures.