Common hydraulic basic terms

1.Hydraulic circuit: a hydraulic device composed of various hydraulic components with certain functions;

2.Circuit diagram: a hydraulic circuit diagram represented by hydraulic graphic symbols;

3.Drainage: from the channel (or pipe) in the hydraulic component, the oil returning to the oil tank or collector, etc. or this oil return phenomenon;

4.Hydraulic station: a hydraulic source device consisting of a hydraulic pump, a driving motor, an oil tank, an overflow valve, or a hydraulic device including a control valve;

5.Oil leakage: a small amount of oil flowing out from the part that should be sealed under normal conditions;

6.Rated pressure: the highest pressure that can be used continuously;

7.Static seal: used for static parts to prevent liquid leakage;

8.Back pressure: the pressure acting on the oil return side of the hydraulic circuit or in the opposite direction of the pressure acting surface;

9.Dynamic seal: used for sealing relative sliding parts;

10.Shock pressure: the maximum value of the rising pressure during the transition;

11.Fluid clamping phenomenon: inside the slide valve, etc., due to the inhomogeneity of the flow, the pressure distribution on the central axis is unbalanced, and the valve core is pressed to the valve body (or valve sleeve), so that it cannot move. ;

12.Opening pressure: such as a one-way valve or overflow valve, etc., when the pressure rises to the point where the valve starts to open and reaches a certain flow rate;

13.Cavitation: The pressure of the flowing liquid drops to the saturated vapor pressure or air separation pressure in a local area, and bubbles are formed due to the generation of steam and the separation of dissolved air, which is the phenomenon of cavitation. When the bubbles collapse in the flow, ultra-high pressure will appear in the local area, and noise will be generated;

14.Closing pressure: such as one-way valve or relief valve, when the inlet pressure of the valve drops to the point where the valve starts to close and the flow rate decreases below a certain amount;

15.Rated flow: under certain conditions, the guaranteed flow;

16.Flow jumping phenomenon: In the speed regulating valve (flow control valve with pressure compensation), when the fluid starts to flow through, the flow momentarily exceeds the set value;

17.Flow rate: generally refers to the volume of liquid output by a hydraulic pump per unit time;

18.Flutter: In order to reduce the impact of friction and fluid clamping on the slide valve and improve its characteristics, a higher frequency vibration is added;

19.Displacement: the volume of liquid output (or input) per revolution of a positive displacement hydraulic pump (or motor);

20.Hydraulic balance: use hydraulic pressure to balance the load (including the equipment itself);

21.Fluid power: the power of the fluid, which is actually expressed by the product of flow and pressure for hydraulic pressure；

22.Inlet throttling mode: the throttle valve is installed in the pipeline on the inlet side of the actuator, and the action speed is adjusted through throttling;

23.Outlet throttling mode: the throttling valve is installed in the pipeline on the outlet side of the actuator, and the action speed is adjusted by throttling

24.Hydraulic transmission device: A device that uses the pressure of fluid to transmit power. Positive displacement hydraulic pumps and hydraulic actuators (hydraulic cylinders or hydraulic motors) are used in such installations.