In recent years, with the development of hydraulic industry, the reliability of hydraulic components has been continuously improved and the cost has been continuously reduced. At home and abroad, there have been all hydraulic driven construction machinery, such as all hydraulic bulldozer, all hydraulic ground leveler, all hydraulic forklift, all hydraulic crane and all hydraulic excavator. Hydraulic transmission is more and more widely used in modern construction machinery because of its many advantages. This article will summarize the advantages of hydraulic transmission.
(1) Under the same power, the hydraulic device has the advantages of small volume, light weight and compact structure. For example, the volume and mass of the hydraulic motor is only about 12% of that of the motor with the same power.
(2) The hydraulic device works smoothly. Due to its light weight, small inertia and fast response, the hydraulic device is easy to realize rapid start, braking and frequent commutation. The reversing frequency of the hydraulic device can reach 550 times /min when realizing reciprocating rotary motion and 1000 times /min when realizing reciprocating linear motion.
(3) The hydraulic device can realize stepless speed regulation in a large range, and the speed regulation range can reach 2000. The speed can be adjusted during operation.
(4) Hydraulic transmission is easy to realize automation. This is because it is easy to adjust or control the liquid pressure, flow rate or flow direction. When hydraulic control is combined with electrical control, electronic control or pneumatic control, the whole transmission device can realize very complex steps. The new technology of hydraulic control for construction machinery operates in sequence and accepts remote control. In recent years, with the close combination of hydraulic transmission and microelectronics technology, it is possible to transmit as much power as possible in as small a space as possible and control it accurately.
(5) The hydraulic device is easy to realize overload protection. The hydraulic cylinder and the hydraulic motor can work under the stall state for a long time without overload, which is impossible for the electrical transmission device and the mechanical transmission device. The hydraulic parts can be lubricated by themselves and have a long service life.
(6) Because the hydraulic components have been standardized, serialized and generalized, the design, manufacture and use of the hydraulic system are more convenient. The arrangement of hydraulic components also has greater mobility.
(7) Using hydraulic transmission to realize linear motion is much simpler than mechanical transmission. However, hydraulic transmission can not guarantee strict transmission ratio, with large energy loss, sensitive to oil temperature change, high manufacturing precision and high cost.
