What Is a Hydraulic Unit?
A hydraulic unit is a device that supplies oil with a certain pressure to drive a machine that requires more power.
An oil tank, motor, pump, etc., are combined to push oil. First, an external electric motor drives the hydraulic pump, and then the propagated hydraulic pressure is used to move the actuators (hydraulic motors and cylinders) to generate work.
The amount of oil discharged depends on the speed, power, size, and number of actuators. The output pressure can also be controlled by the actuator.
Applications of Hydraulic Units
Hydraulic units are used to drive many types of construction equipment, industrial vehicles, and agricultural machinery. Typical examples include excavators, forklifts, tractors, and dump trucks.
They are also used in industrial machinery, such as iron and steel-making machinery, machine tools, and injection molding machines.
Since these large machines need to exert power efficiently with less power, the power output technology using hydraulic units has become indispensable in today’s industrial field.
Principle of Hydraulic Units
Hydraulic units use the power of hydraulic pressure to generate physical pressure that is difficult to produce by human power.
This mechanism is explained by Pascal’s principle.
Pascal’s principle states that when pressure is applied to a liquid enclosed in a sealed container, the pressure propagates equally throughout the liquid.
Since a constant pressure propagates, the larger the cross-sectional area that the liquid touches, the greater the applied force.
For example, two pistons with different cross-sectional areas are connected by a tube, and the liquid is enclosed in the tube.
When the piston with the smaller cross-sectional area is pushed into the liquid, the pressure propagates through the liquid, and the piston with the larger cross-sectional area is lifted. As a result, a larger force is applied to the larger piston.
Thus, even if less force is applied, a greater output can be obtained. Hydraulics also utilize a similar principle.
Since oil is used as the medium, the direction of force can be freely changed according to the shape of the hydraulic cylinder. It is also easy to divert the flow in piping. Furthermore, the size and speed of the force can be easily adjusted.