Fluid transmission includes gas (pressure) transmission and liquid transmission. Liquid transmission is divided into hydraulic transmission, hydraulic transmission and liquid viscous transmission. Hydraulic transmission is based on Paka's law, which transmits power with the pressure energy of a liquid; hydraulic transmission is based on Euler's equation, which transmits power with a short change in liquid momentum; liquid viscous transmission is based on Newton's internal friction law, which transmits power with the viscosity of a liquid .
The basic components of hydraulic transmission are hydraulic coupling and torque converter. The basic components of a fluid coupling are a pump wheel and a turbine which have a number of radial plane blades and constitute a working chamber. The hydraulic transmission oil circulates at high speed in the working chamber to transmit power. The oil is subjected to centrifugal movement due to the centrifugal force while following the impeller movement of the pump wheel. It absorbs mechanical energy from the pump wheel (and input shaft) and converts it into momentum moment (mVR) ) Incremental, high-speed liquid flow from the pump wheel into the turbine to centripetal flow to release the momentum moment, pushing the turbine (and output shaft) to rotate, driving the working machine (and load) to do work. The basic components of a torque converter are a pump wheel, a turbine, and a guide wheel. They are all working wheels with space (bent) blades, arranged in a related order to form a working chamber. The hydraulic transmission oil is stirred by the pump wheel turbine in the working chamber, so that the liquid flow obtains the momentum moment increment. After the guide wheel changes the direction of the liquid flow, it rushes into the turbine and releases the momentum moment (kinetic energy) to drive the turbine to rotate the work machine to do work.
my country's hydraulic components have developed rapidly in recent years. In 2003, the national annual output of hydraulic couplings was about 70,000 units. It is widely used in the transmission of belt conveyors, scraper conveyors, ball mills, fans, compressors, water pumps and oil pumps to improve the quality of transmission and save energy. At present, the maximum output speed of my country's hydraulic coupling is 6500r/min, the minimum power is 0.3kW, and the maximum power is 7100kW. The development trend of hydraulic coupling is high speed and high power.
Internationally, the hydraulic coupling 名媛直播 are the most famous by German Voith Co., Ltd. According to the data, there are already 名媛直播 with a speed of 20,000r/min and a power of 55,000kW, which shows that there is still a considerable gap between my country and it. Of course, high-power hydraulic components have higher requirements for hydraulic transmission oil.
Hydraulic torque converters are mainly used in construction machinery, petroleum machinery and diesel locomotives. The torque converter is mainly matched with the internal combustion engine, and its speed range is 2000～3000r/min. There are many applications of construction machinery, the maximum power is about 700HP, and the annual output is about 70,000 units. Petroleum machinery has fewer applications and the power reaches 1500HP. Diesel locomotives have fewer applications and power up to 3000HP.
Liquid viscous transmission is an emerging discipline of liquid transmission, which is still in its infancy in my country. Although liquid viscous transmission 名媛直播 (such as liquid viscous speed control clutch) and hydraulic transmission 名媛直播 (such as speed regulating type hydraulic coupling) are essentially different, but due to similar performance and the same use (speed regulation energy saving) , In several technical activities (such as the development of development plans, standards, technical management, ordering activities, etc.) are considered to be the same type, and the hydraulic industry has commonality.
