A complete hydraulic system consists of five main components: power components, actuators, control components, auxiliary components (accessories), and hydraulic fluid.
Power Components
The function of power components is to convert the mechanical energy of a prime mover into the pressure energy of a fluid. This role is fulfilled by the hydraulic pump within the system, which supplies power to the entire hydraulic circuit. Common structural types of hydraulic pumps include gear pumps, vane pumps, piston pumps, and screw pumps.
Actuators
The function of actuators (such as hydraulic cylinders and hydraulic motors) is to convert the pressure energy of the fluid back into mechanical energy, thereby driving the load to perform linear reciprocating motion or rotary motion.
Control Components
Control components (specifically, various types of hydraulic valves) serve to control and regulate the pressure, flow rate, and direction of the fluid within the hydraulic system. Based on their specific control functions, hydraulic valves can be classified into pressure control valves, flow control valves, and directional control valves. Pressure control valves include relief valves (safety valves), pressure-reducing valves, sequence valves, pressure relays, and others; flow control valves include throttle valves, flow control valves, flow dividers/combiners, and others; directional control valves include check valves, pilot-operated check valves, shuttle valves, directional control valves (spool valves), and others. Based on their control methods, hydraulic valves can be further categorized into on/off control valves, fixed-value control valves, and proportional control valves.
Auxiliary Components
Auxiliary components include oil tanks, oil filters, coolers, heaters, accumulators, hydraulic tubing and fittings, seals, quick-disconnect couplings, high-pressure ball valves, hose assemblies, pressure test ports, pressure gauges, oil level indicators, oil thermometers, and other accessories.
Hydraulic Fluid
Hydraulic fluid serves as the working medium responsible for transmitting energy within the hydraulic system. It encompasses several major categories, including various mineral oils, emulsions, and synthetic hydraulic fluids.
