Hydraulic Fundamentals Flashcards
Working conductors carry ____ pump flow rate.
Full
Flexible hose is depicted graphically with an ____ line.
Arced
Pilot lines are ____-sensing lines that carry pressurized oil to operate system components.
Pressure
____ lines carry internal leakage oil from certain hydraulic components back to the reservoir.
Drain
Hydraulic motors convert ____ energy into rotational mechanical energy.
Hydraulic
Hydraulic cylinders that can be hydraulically actuated in one direction only are ____ cylinders.
Single-acting
Hydraulic cylinders that can be actuated in two directions are ____ cylinders.
Double-acting
Three major types of hydraulic valves are:
Pressure control valves
Flow control valves
Directional control vavles
An orifice is a ____ to oil flow.
Restriction
Filters remove ____ from hydraulic oil.
Contamination
Coolers remove ____ energy from the hydraulic oil.
Heat
Heat exchangers add ____ energy to the hydraulic oil.
Heat
Accumulators are installed in a hydraulic system to store ____ energy or to absorb ____.
Hydraulic
Shock
Avoid working in ____ points.
Pinch
Do not cut, heat, weld, solder or use a torch near ____ hydraulic lines.
Pressurized
An ________ is a device that converts hydraulic power into mechanical power.
Actuator.
Ex. Hydraulic motors, Cylinders.
____ ____ describes the volume of a fluid passing a given point in a given period of time.
Flow Rate.
Imperial system: Gallons Per Minute (GPM)
Metric system: Litres Per Minute (L/min)
The term ____ refers to any substance that flows.
Fluid.
Liquids & Gases are both fluids.
____ is described as a push or pull.
Force.
Imperial system: Pound (lb)
Metric system: Newton (N)
__________ is the science that pertains to the transmission of force and/or motion through a fluid.
Hydraulics
____________ is the area of hydraulics that pertains to the transmission of force and/or motion using liquid motion.
Hydrodynamics
Ex. Waterwheels, Hydroelectric Turbines, Etc.
_____________ is the area of hydraulics that pertains to the transmission of force and/or motion using confined liquids.
Hydrostatics
Ex. Hydraulic Jacks, Power Steering, Etc.
____ is the amount of material in an object.
Mass
An _______ is a device used to provide a restriction to liquid flow. It creates a pressure drop.
Orifice
_______ is the amount of work done in a given period of time.
Power
Imperial: Horsepower (hp)
Metric: Watt (W)
_______ is defined as a force per unit area. This is caused by a resistance to liquid flow and is responsible for generating force.
Pressure
Imperial: pound per square inch (psi)
Metric: Newton per meter squared (Nm2, pascal)
A ____ is a device that converts mechanical power into hydraulic power.
Pump
______ is the absence of pressure.
Vacuum
_________ describes the rate of motion (speed).
Velocity
Imperial: feet per second (ft/sec)
Metric: meters per second (m/sec)
_________ is the internal capacity of space or chamber.
Volume
____ is the product of force acting through a distance.
Work
_____ are compressible and _______ resist compression.
Gases
Liquids
Pressure applied to a confined liquid is transmitted equally and undiminished in all directions at right angles to all surfaces.
Pascal’s Law.
The resistance to flow in a hydraulic system comes from which two sources?
Pressure Loss
The Load
________ ____ is the pressure that is created by the resistance of system components.
Pressure Loss
Pressure losses + Pressure required to overcome the load =
Total Pressure
If the force applied to a surface area is doubled the pressure will:
Double
If the surface area doubles and the applied force does not change the pressure will
be reduced by half.
Double-acting Cylinders are used because they are able to:
Hydraulically extend and retract.
Series Hydraulic Circuits offer ___ path for oil to flow.
one
Parallel Hydraulic Circuits offer _______ path for oil to flow.
more than one
The pressure created by the weight of a fluid is known as ____ ________.
Head Pressure
Pressure that exists below atmospheric (14.7psi, 101.34kPa) is referred to as:
vacuum
partial vacuum
sub-atmospheric pressure
The most common tool used to measure pressure is:
The Bourdon Tube Pressure Gauge
While Gauge Pressure (Psig) measurements ignore atmospheric pressure, ________ ________ measurements include it.
Absolute Pressure (Psia)
