Hydraulic pumps can be hydrostatic or hydrodynamic. They’re used in hydraulic drive systems, as well as other machines.A pump is a machine that converts mechanical energy into hydraulic power or fluid pressure.The pump can produce enough flow to overcome pressure caused by the load at the outlet.When automatic pumps operate, a system of forces creates a vacuum in the inlet and forces liquid into the system. A hydrostatic pump is a positive-displacement pump while a hydrodynamic pump can take many shapes, either fixed or variable displacement. Hydrostatic pumps are often used in everyday life while they are more rare with hydrodynamic pumps. All types of hydrostatic pumps use Pascal’s law to operate.
A change in pressure at any point in an enclosed fluid at rest is transmitted undiminished to all points in the fluid.
Pressure exerted on a fluid in an enclosed container is transmitted equally and undiminished to all parts of the container and acts at right angle to the enclosing walls.
Alternate definition: The pressure applied to any part of the enclosed liquid will be transmitted equally in all directions through the liquid.
History of the hydraulic pump
The use of fluid power goes back thousands of years when ancient Egyptians used hydraulics to irrigate crops. But it wasn’t until much later that the laws of hydrodynamics were discovered and presented to the masses.
1648: French physicist Blaise Pascal realized that pressure on a confined fluid exerted an equal force in all directions, and those forces could be harnessed.
1738: Nearly 100 years later, Daniel Bernoulli put Pascal’s fluid power discovery to use by pressurizing water in pumps and mills using Bernoulli’s principle.
1795: Joseph Bramah patented the first hydraulic press in England, paving the way for the industrial revolution. Hydraulic presses harnessed fluid power to automate all types of manufacturing equipment, ranging from printing presses and cranes to machines for cutting and stamping.
In the time span of 75 years, hydraulic cylinders have gone from being used solely on crans to being used in hydroelectric power production. They have also become popular for use in aircraft control surfaces and even watercraft of all sizes. The many uses for this type of technology stretch across a broad spectrum.
Hydraulic push, pull, and lifting applications can provide up to 10 times the power as an electric motor. The precise control and reliability makes it a safer move on or around hydraulic equipment.With the assistance of more modern technology and the perfect combination of science and math, hydraulic cylinders that are “smart” have become available in a technologically-advanced format.
Next we should: understand the main components of the hydraulic pump