Explain Hydraulics speaks to what are hydraulics and how are hydraulics used. It allows designers, manufacturers, service people and the end user to converse using technical jargon understood by all.
Hydraulics work because liquids cannot be compressed and the hydraulic fluid (liquid) is easily moved through pipes, hoses and control devices to do work.
It is in fact the science of energy transmission through a liquid which depends on some characteristics of a liquid and an understanding how force is transmitted through a liquid. To understand hydraulics some basic principles must be understood.
A fluid is a substance that can flow and possess no definite shape.
A liquid, like a gas, is a substance consisting of molecules and unlike a gas these molecules are close to each other. Unlike a solid these molecules are not so close that they are rigid.
Molecular Energy states that molecules move on a continuous basis and move past each other even when the liquid appears at rest. This molecular movement is molecular energy.
The theory of Shapes of Liquids states that due to molecular movement a liquid is able to assume the shape of any container.
Viscosity is the term used to explain this liquid ability. Liquids for the most part are considered to be incompressible due to the fact that their molecules are already very close to each other and thus possess particular advantages for transmitting a force.
There are four methods of force or energy transmission which are mechanical, electrical, hydraulic and pneumatic which are capable of transmitting force also known as kinetic energy.
Hydraulics occurs when a static force is transmitted in a confined liquid in the form of hydraulic pressure. The pressure is transmitted equally throughout the liquid and since fluid can take the shape of any container the pressure will be transmitted regardless of the shape of the container.
Pascal’s Law states that it is the property of a liquid to transmit pressure equally throughout itself. It states that pressure (psi) is equal to force (lbs) divided by area (sq inches). The metric equivalent is bar is equal to force (Newton) divided by area (sq meters).