vickers industrial hydraulics Flashcards
- State Pascal’s Law.
Pressure applied to a confined fluid at rest; force is
transmitted equally in every direction and always at
right angles to the containing surface.
- Define pressure.
Pressure is defined as the force per unit area. It is calculated by dividing the
force by the area over which the force is distributed. This is also stated as:
Force (F) = Pressure (P) x Area (A)
- If a force of 1000 pounds is applied over an
area of 20 square inches, what is the pressure?
50 psi
- What is meant by “conservation of energy” ?
Energy cannot be destroyed, but it may be converted
from one form to another.
- What is the output component of a hydraulic
system named? The input component?
pump out and actuators in
- What is the prime mover?
electric motor or engine
- Name several advantages of a hydraulic
system.
Variable Speed Reversible Overload Protection - pressure relief valve. Small Packages Can be stalled Hydraulic oil Pressure in a column of fluid
- What is the origin of the term “hydraulics’’?
water pipe
- What makes petroleum oil suitable as a
hydraulic fluid?
nearly incompressible, good lub
- What is the pressure at the bottom of a 20
foot column of oil?
8 psi
- What can you say definitely about the pressures on opposite sides of an orifice when oil is flowing through it?
The pressure is different, i.e. there is a pressure drop.
- What pressure is usually available to charge
the pump inlet?
the inlet of a pump normally is charged with oil by a difference in pressure between the reservoir and the pump inlet. most pump manufacturers recommend a vacuum of no more than 5 inches of mercury, 12.2 psia.
- Why should the pump inlet vacuum be minimized?
to create flow
- What is the function of the pump?
to create flow
- Why is loss of pressure usually not a symptom of pump malfunction?
Because pressure can be lost only when there is a leakage path that will divert all the flow from the pump.
