Whether you work with hydraulic drive systems every day or you just want to learn about the characteristics and essential components of a hydraulic system, this article provides a comprehensive overview.
Principles Of A Hydraulic Drive System
The most basic principle of a hydraulic drive system is that it uses pressurised fluid to exert force.
The scientific principle that a hydraulic system works on is Pascal’s Principle. Pascal’s Principle, or Pascal’s Law of mechanics, states that if a fluid is in a closed container and put under pressure, that pressure is not only the same in all directions but that it can be transferred without the diminishing of power.
Pascal’s Law also states that pressure = force divided by the area the force is acting on.
This is how hydraulics works. Fluid under pressure moves a piston, that piston puts the same amount of force on another, bigger piston, which increases the force because the area is increased.
Uses Of Hydraulic Oil
Hydraulic oil, sometimes called hydraulic fluid, is what is pumped around the hydraulic system and put under pressure to activate/move the pistons.
It also acts as a coolant, lubricant, and sealant.
Hydraulic Press
Often used in the fabrication of metal items such as in automotive production. The hydraulic press uses a hydraulic cylinder that directs fluid in a much larger area to exert a huge downward force for crushing and otherwise shaping materials, especially metal.
Hydraulic Cylinder
Within a hydraulic system, there is always a hydraulic cylinder or actuator. The cylinder contains the piston which transfers power from one part of the hydraulic system to the lever or press that will be doing the work.
Hydraulic Motor
A hydraulic motor is a component of a hydraulic system. It is the actuator that transfers the linear force from the pressure of the hydraulic fluid into rotational force.
Hydraulic Valves
The valve component of a hydraulic system regulates and directs the flow of the hydraulic fluid through the system.
Classification Of Hydraulic Valves
There are 3 types of hydraulic valves.
- Flow control valves – these manage the volume of hydraulic fluid/oil that is flowing through your hydraulic system. This helps control the speed of the hydraulic motor (rotational actuator).
- Pressure control valves – can either be on or off switches that close once a certain level of pressure is reached. These are generally for fixed throttle systems. Or they can be gradual control valves which are generally for variable throttle systems.
- Directional control valves – change the direction of the flow of the hydraulic fluid through the hydraulic system.
Open & Closed Systems
Within an open hydraulic system, the flow is continuous and the hydraulic fluid returns to the fluid reservoir. Within a closed hydraulic system, the loop or circuit is continuous and stays pressurised throughout.
Whatever the type of hydraulic system you use, and in whatever application, keeping it serviced and well maintained is key to the safe and effective functioning of any hydraulic machinery.
For advice or to book a service with one of our experts, contact us at MCH Hydraulics today to keep your hydraulics working tomorrow.