In the middle opening system, the main reversing valve of the middle opening system is in the middle position, through which the hydraulic pump is unloaded, and the liquid returns to the oil tank under low pressure. This kind of system generally uses constant displacement pump as oil source; When the reversing valve is in the middle position, the energy transmission starts with a low value that is basically zero, and the energy rises after changing, so that the pressure liquid enters special-purpose orbit motor The actuator acts on the load; When the reversing valve is in the middle position, the internal leakage is very small. Generally, when the same function is achieved, the energy consumption of the intermediate open circuit is smaller. in Zhuhai special-purpose Open system is mostly used for working conditions requiring intermittent movement or supporting load, such as prime movers that do not want to start and stop frequently. The system has high efficiency, and needs to use makeup oil pump and flushing valve for oil makeup and heat exchange.

As a hydraulic equipment, hydraulic motor has been widely used in many factories. Generally, we should master the assembly skills of the hydraulic motor: the hydraulic system should special-purpose orbit motor Correct machining and assembly. The mounting surface of the hydraulic valve on the oil block should be straight, and the sealing surface of the sealing groove should be finished to avoid radial scratches. The preload of the connection between the hydraulic valve and the oil circuit block and the connection between the oil circuit blocks shall be sufficient to prevent surface separation. The hydraulic equipment shall be inspected according to relevant standards before assembly orbit motor Price Check the pressure leakage of system components. If problems are found, corresponding measures shall be taken. If the problem is serious, it should be replaced. Accurately formulate the assembly process documents of hydraulic equipment, configure necessary assembly tools, and strictly follow the assembly process. Keep the hydraulic components, accessories, sealing parts and pipe fittings clean to prevent contamination, and check the integrity of the sealing surface and connecting threads. The hydraulic connector should not be tightened too tightly, otherwise some parts will be severely deformed or even broken, causing leakage. Avoid damaging sealing parts during assembly.

Functions: It is used for the storage, supply and recovery of hydraulic media, the connection between hydraulic components and the transmission of energy carrying hydraulic media, filtering impurities in the hydraulic media, keeping the media required for the normal operation of the system clean, heating or cooling the system, storing and releasing hydraulic energy or absorbing hydraulic pulsation and impact, and displaying the pressure and oil temperature of the system; Hydraulic working medium: various hydraulic oils (fluids), efficacy: as the energy carrying medium of the system, it plays the role of lubrication and cooling while transferring energy. Generally speaking, the hydraulic components that can complete certain specific functions are called hydraulic circuits. In order to meet the working requirements of certain machinery or equipment, the overall structure of several special basic functional circuits connected or combined together is called hydraulic system.

What is the oil supply mode of the hydraulic pump? The straight shaft swashplate plunger pump can be divided into two types: self suction type and pressurized type. Most high-pressure oil supply hydraulic pumps use pneumatic oil tank, and some hydraulic pumps are also equipped with oil make-up slave pump to deliver pressure oil to the oil inlet of the hydraulic pump. The self-priming pump has the characteristics of strong self-priming ability and no need for external oil supply special-purpose orbit motor 。 Bearings for hydraulic pumps. The most important part of the plunger pump is the bearing. If the bearing has clearance, the normal clearance of the three pairs of friction pairs inside the hydraulic pump cannot be guaranteed. At the same time, the hydrostatic support oil film thickness of each friction pair will be damaged, thus reducing the service life of the plunger pump bearing. According to the data provided by the manufacturer of the hydraulic pump, the average service life of the bearing is 10000 hours. If the service life exceeds this value, a new port shall be replaced. 3、 Conclusion. The service life of the piston pump is related to the maintenance at ordinary times, the quantity and quality of the hydraulic oil, and the cleanliness of the oil. At the same time, avoid orbit motor Price The particles in the oil will wear the friction pair of the plunger pump, which is also an effective method to extend its service life.

With the rapid development of China's economy, since the reform and opening up, the machinery industry has improved the advanced productivity in China by constantly introducing foreign technology. Especially after China's accession to the WTO, the machinery industry has accelerated scientific and technological innovation, and the annual export of equipment has continued to grow. With the continuous technological innovation of the hydraulic press industry in China, a number of high-tech industrial companies have emerged, and there are thousands of domestic production enterprises with a certain scale. Hydraulic press products are commonly used in stamping processing and stamping forming processes, such as forging, stamping, cold extrusion, straightening, bending, flanging, plate stretching, powder metallurgy, press fitting, etc. They are metal, plastic, rubber, wood, powder and other products. It can not only meet the functional diversification of electromechanical products to the maximum extent, but also is the basic guarantee for completing major projects and major technological transformation. Now the hydraulic press products have been widely used in automobile, engineering machinery, agricultural machinery, machine tools, plastic machinery, metallurgy and mining, power generation equipment, railway, ship, light industry, electronics, and defense industry products.

Most of its hydraulic system uses working medium, such as hydraulic oil with continuous fluidity, which converts the mechanical energy of the prime mover driving the pump into the pressure energy of the liquid through the hydraulic pump, and sends it to the actuator (hydraulic cylinder, hydraulic motor or swing hydraulic motor) through various control valves, such as pressure, flow, direction, etc., to convert it into mechanical energy to drive the load. This hydraulic system is generally composed of the following parts: power source, actuator, control valve, hydraulic auxiliary device and hydraulic working medium, which play their respective roles: power source: prime mover (motor or internal combustion engine) and hydraulic pump, whose role is to convert the mechanical energy generated by the prime mover into the pressure energy of liquid, and output oil with a certain pressure;