A complete hydraulic system consists of five parts, namely power element, actuator, control element, auxiliary element and hydraulic medium. The function of the power element is to convert the mechanical energy of the prime mover into the pressure energy of the liquid, which refers to the oil pump in the hydraulic system, which provides power to the entire hydraulic system. The structural forms of hydraulic pumps generally include gear pumps, vane pumps and plunger pumps. The function of actuators (such as hydraulic cylinders and hydraulic motors) is to convert the pressure energy of the liquid into mechanical energy and drive the load to make linear reciprocating motion or rotary motion. The control element (i.e. various hydraulic valves) controls and regulates the pressure, flow and direction of the liquid in the hydraulic system. According to different control functions, hydraulic valves can be divided into pressure control valves, flow control valves and directional control valves. Pressure control valves are further divided into overflow valves (safety valves), pressure reducing valves, sequence valves, pressure relays, etc.; flow control valves include throttle valves, regulating valves, flow diversion and collection valves, etc.; directional control valves include check valves, hydraulic control check valves, shuttle valves, reversing valves, etc. According to different control methods, hydraulic valves can be divided into switch control valves, fixed value control valves and proportional control valves. Auxiliary components include oil tank, oil filter, oil pipe and pipe joint, sealing ring, pressure gauge, oil level and oil temperature gauge, etc.
The hydraulic system is mainly composed of five parts: power element (oil pump), actuator (oil cylinder or hydraulic motor), control element (various valves), auxiliary elements and working medium. 1. Power element (oil pump) Its function is to convert the mechanical energy of the liquid into hydraulic pressure energy using the prime mover; it is the power part in hydraulic transmission. 2. Actuator (oil cylinder, hydraulic motor) It converts the hydraulic energy of the liquid into mechanical energy. Among them, the oil cylinder moves linearly and the motor moves rotaryly. 3. Control elements include pressure valves, flow valves and directional valves. Their function is to steplessly adjust the speed of the hydraulic motor according to needs, and to adjust and control the pressure, flow and flow direction of the working fluid in the hydraulic system. 4. Auxiliary components Other components besides the above three parts include pressure gauge, oil filter, energy storage device, cooler, pipe fittings {mainly including: various pipe joints (flared, welded, ferrule, SAE flange), high-pressure ball valve, quick-change joint, hose assembly, pressure measuring joint, pipe clamp, etc.} and oil tank, etc., which are also very important. 5. Working medium refers to the hydraulic oil or emulsion in various hydraulic transmissions, which realizes energy conversion through oil pumps and hydraulic motors.
