These machines are used in many fields, including construction, farming and fishing. Construction workers who operate backhoes, loaders, cranes, shovels and fork lifts are using hydraulic power units. Hydraulic power is used to power some of the rides you love at your favorite amusement park? Your local garbage collector utilizes hydraulic power to compact the trash he has collected. Rescue workers save the lives of people in car accidents using the Jaws of Life which, you guessed it, uses hydraulic power. Car mechanics use this type of power to operate the machinery that lifts the cars up so they can work underneath them easily.
Another example of the implementation of a hydraulic power system is the brakes on your car. If you have ever been around your mechanic when he works on your cars braking system you should recall that he needed to “bleed” the brakes. The reason this is done is to remove the air bubbles from the brake lines. When air is in the system the piston(s) fail to work correctly which could cause your brakes work incorrectly. When you push down your brake pedal the hydraulic fluid, a/k/a brake fluid, is pressed down into the piston(s) which moves them. This causes force on the brake pads which applies pressure on the rotor. The friction between the pads and rotor slow down your car. Keeping the brake fluid levels correct is essential to a good working set of brakes on your car. If a hose leaks, your fluid level drops, this causes problems with your braking system. Hydraulic Power Units are well oiled machines.
So, now we know that hydraulic power, used in many applications, is transmitted by the controlled circulation of pressurized fluid in a machine resulting in mechanical output that completes a specific task. The high-pressure liquid used in a hydraulic power unit is called hydraulic fluid. The fluid travels throughout the hydraulic machine via hoses and tubes. Control valves regulate the amount of fluid circulated during operation of the machine.
Hydraulic fluid, a main component of a hydraulic machine, is normally comprised of petroleum oil and contains other additives such as water and glycol. The type of fluid used in the machine depends on the application for which the machine will be used. Excess hydraulic fluid is contained in a reservoir which is designed to separate air from the fluid. Contaminants, dirt and other foreign particles, are removed from the hydraulic fluid by use of filters. The fluid is then reintroduced into the machine. This cleaning process helps keep the machine working properly.
Hydraulic tubes, pipes or hoses may be used to transfer hydraulic fluid. Tubes, pipes and hoses are graded according to various pressure ranges. It is pertinent that these parts are able to withstand the pressure within the system in order to keep the system working properly.