Physical meaning of terms commonly used in hydraulic systems

Hydraulic circuit: A hydraulic device consisting of various hydraulic components with certain functions.
Circuit diagram: Hydraulic circuit diagram expressed in hydraulic graphic symbols.
Hydraulic station: hydraulic pumps, drive motors, tanks, relief valves and other components of the hydraulic source device or control valves, including the hydraulic device
Rated pressure: the highest pressure that can be used continuously
Back pressure: the return side of the hydraulic circuit or the opposite direction of the pressure surface, the role of the pressure
Shock pressure [force]: The maximum value of the rising pressure during the transition process.
Opening pressure [force]: such as check valves or relief valves, etc., when the pressure rises to the valve begins to open, up to a certain flow rate of pressure
Close pressure [force]: such as check valves or relief valves, etc., when the valve inlet pressure drops to the valve began to close, the flow rate is reduced to a specified amount of the following pressure
Rated flow: under certain conditions, to ensure that the flow rate
Flow: generally refers to the hydraulic pump in a unit of time the volume of liquid output
Displacement: positive displacement hydraulic pump (or motor) per revolution output (or input) of the volume of liquid
Fluid power: the fluid has the power, for hydraulic is actually expressed as the product of flow and pressure
Piping: conduction of the working fluid piping and piping system
Main line: including suction line, pressure line and return line
Drain line: refers to the oil drain back to the oil pipe, or to lead it into the tank piping
Passage: through the component or in its internal machining method or casting of the channel of the conductive fluid oil port, connection port component on the channel of the fluid conductive openings
Throttling: Reduce the flow area, so that the pipeline or channel internal resistance mechanism, there are long orifice throttling and thin edge throttling
Slide valve spool (cylindrical spool): with the cylindrical sliding surface, when it moves along the axial direction, for the flow path opening and closing of parts
Drain: from the hydraulic components in the channel (or pipe), to the tank or collector, etc. return of oil or this oil return phenomenon
Leakage: from the normal state should be sealed out of the part of a small amount of oil flow
Static seal: Used in stationary parts to prevent liquid leakage
Dynamic seal: Used for sealing the relative sliding part.
Fluid jamming phenomenon: in the internal slide valve, etc., due to the unevenness of the flow, resulting in an imbalance in the distribution of pressure on the central axis, the spool to the valve body (or valve sleeve), so that it can not act phenomenon
Cavitation phenomenon: the pressure of the flowing liquid, in the local range, down to saturated vapor pressure or air separation pressure, due to the generation of steam and dissolved air and other separation and the generation of bubbles, that is, the phenomenon of cavitation. When bubbles collapse in the flow, ultra-high pressure occurs within a localized range and noise is generated.
Flow jump phenomenon: In a speed control valve (flow control valve with pressure compensation), when the fluid starts to flow through, the flow rate instantaneously exceeds the set value.
Chattering: Higher frequency vibration added to reduce the effects of friction and fluid clamping on slide-type valves and improve their characteristics.
Hydraulic balancing: the use of hydraulic pressure to balance the load (including the device itself)
Fluid transmission device: the fluid as a medium to transfer power device
Inlet throttling mode: throttle valve installed in the pipeline on the inlet side of the actuator, through throttling to regulate the speed of action mode
Outlet throttling method: throttle valve is installed in the pipeline on the outlet side of the actuator, and the speed of action is adjusted by throttling.
Bypass throttling method: A part of the flow to the actuator is flowed back to the tank through the throttle valve installed in the bypass line to regulate the speed of the actuator.
Electro-hydraulic method: the combination of solenoid and other electrical components into the hydraulic manipulator method
Pilot control method: A method that controls the pressure introduced by a pilot valve or the like.
Hydraulic transmission: A device that utilizes the pressure energy of a fluid to transmit power. In this type of device, a positive displacement hydraulic pump and a hydraulic actuator (hydraulic cylinder or hydraulic motor) are used.