Hydraulics TPC Flashcards by Foxy Loser

What characteristic of a fluid does the term specific gravity describe?

Density

How well did you know this?

Not at all

Perfectly

Pressure is measured in ________ in the English system

PSI

How well did you know this?

Not at all

Perfectly

Which of the following is not needed in order to calculate the work a hydraulic cylinder can do?

Power (ft-lb/min)

How well did you know this?

Not at all

Perfectly

Pascal’s laws states that pressure exerted on a confined liquid:

Is distributed equally throughout the liquid

How well did you know this?

Not at all

Perfectly

According to Bournooli’s principle, when fluid flow increases in a system, the pressure:

Decreases

How well did you know this?

Not at all

Perfectly

A hydraulic fluid must be able to do all of the following except:

Compress easily

How well did you know this?

Not at all

Perfectly

A hydraulic fluid that exhibits little change in viscosity when heated is said to have a high:

Viscosity index

How well did you know this?

Not at all

Perfectly

The ability of a fluid to penetrate into small clearances between closely fitted parts is determined by the fluid’s

Viscosity

How well did you know this?

Not at all

Perfectly

Which of the following, when added to hydraulic fluid, will limit oxidation?

A chemical inhibitor

How well did you know this?

Not at all

Perfectly

The best method of controlling hydraulic fluid contamination is the use of:

Good maintenance procedure

How well did you know this?

Not at all

Perfectly

The ability of a filter or strainer to remove 100% of the contaminant particles of a particular size from a hydraulic fluid is called:

Absolute rating

How well did you know this?

Not at all

Perfectly

When the maximum allowable pressure drop of a filter is reached, the filter will:

Allow particles to pass through the medium

How well did you know this?

Not at all

Perfectly

The purpose of the filter in a hydraulic system is to:

Remove small contaminants

How well did you know this?

Not at all

Perfectly

The purpose of the filter in a hydraulic system is to:

Remove small contaminants

How well did you know this?

Not at all

Perfectly

Depth filters do not:

Have a long service life

How well did you know this?

Not at all

Perfectly

Surface filter media made of sintered metal powders are use in high-pressure systems because of their:

Thick mass

How well did you know this?

Not at all

Perfectly

The separation of contaminants from hydraulic fluid in a resovoir is aided by

Slow fluid movement

How well did you know this?

Not at all

Perfectly

What is used in a hydraulic reservoir to aid fluid cooling?

A baffle

How well did you know this?

Not at all

Perfectly

To maintain the temperature of a hydraulic fluid effectively, the reservoir should have:

Thin walls

How well did you know this?

Not at all

Perfectly

An air breather is installed on a fluid reservoir to:

Vent the reservoir

How well did you know this?

Not at all

Perfectly

Peak hydraulic system demands are usually met by the use of an:

Accumulator

How well did you know this?

Not at all

Perfectly

The resistance of a hydraulic system to fluid flow causes:

Pressure

How well did you know this?

Not at all

Perfectly

Pump capacity is rated in all of the following terms except:

Pounds PSI

How well did you know this?

Not at all

Perfectly

The ratio fo the actual delivery rate of the pump to its displacement is its:

Volumetric efficiency

How well did you know this?

Not at all

Perfectly

Which of the following is not a type of gear pump?

Vane

Internal gear pumps are normally used in applications that have:

Pressures of less than 1000psi

The flow rate of hydraulic fluid through piping or tubing is measured in

GPM

Pressure loss in a hydraulic line depends on the

Flow velocity

Hydraulic lines should NEVER be constructed of

Galvanized pipe

In non critical applications having no severe stress, safe working pressures of hydraulic piping are bases of providing a safety factor of:

A disadvantage of using hose in hydraulic systems instead of piping or tubing is that the hose:

Is less permanent

Which of the following kinds of valves should be used in hydraulic system to change the directions of motion of the cylinder?

Directional control valve

A three way valve is identified by its three…

Paths

The closing force of a direct acting solenoid valve is approximately

15lbs

The construction of a spool valve causes it to:

Be partially balanced

A four way valve that can operate in three positions is called a

Closed crossover valve

The operating differential pressure of a relief valve is the difference between its maximum pressure and the

Cracking pressure

The flow from the outlet of a sequence valve is at

Line pressure

Fluid pressure in one section of a hydraulic system is limited by a

Reducing valve

A shock suppressor is used in a hydraulic system as

Protection against pressure surges

A meter-out flow-control valve is used to regulate fluid flow from a(n)

Actuator

Straight line mechanical force is created by

Hydraulic cylinder

The force exerted by a double acting piston is

Less on the rod side

A cylinder in which the retracting stroke is the power stroke is called a

Pull-type cylinder

When a hydraulic cylinder is added to an existing system, be sure that the

Pump capacity is adequate

Mechanical shock is controlled in a Hydraulic cylinder by means of

Cushioning device

Which of the following statements about hydraulic motors is true?

They are all positive displacement types

The pressure range of a hydraulic motor may vary from

100 to 5000 psi

the overall efficiency of a hydraulic motor is defined as the

Output horsepower divided by the input horsepower

A crescent shaped separator is used on some _________ gear motors

Internal

Internal leakage in hydraulic gear motor is held to a minimum by the use of

Wear plates

The amount of matter in an object and its resistance to change in motion is called its - density - mass - volume - weight

Mass

The Law of Conservation of Energy states that energy cannot be created or destroyed, it can only be - amplified -conserved - diluted - transformed

Transformed

Turbulent flow conditions: - can release air suspended in the hydraulic fluid - conserve power - cool the hydraulic fluid - occur when fluid viscosity is too high

Can release air suspended in the hydraulic fluid

A fluid rated at 250 SSU has a ____________ than a fluid rated at 150 SSU - higher flow rate - higher viscosity - lower film strength - lower pour point temperature

Higher viscosity

The viscosity of a fluid is a measure of its resistance to

Flow

How should cylinders used for heavy-duty pushing or thrust applications be mounted?

Square flanges on the cap end

Which type of motor toque changes with changes in fluid pressure?

Runnning

A counter-balance valve is normally a _________ valve

Double-poppet

The two categories of relief valve are _______ and ________.

Direct acting, and pilot operated

The pressure at which a check valve starts to open is called its ______ pressure

Cracking

In applications using a needle valve that must be shut off frequently, a ________ should be used

Soft seat

Directional valves are sometimes classified by the way the fluid flows when the valve is in the ________ position.

Center

Which of the following connections are suitable for joining 1 1/2” pipe?

Threaded

The most important factor is selecting hydraulic line is the

Flow rate

Pressure loss in a hydraulic line depends on the

Flow velocity

A vane pump with the rotor place off-center is classified as a(n) _________ pump

Unbalanced

Pumps operating at high pressures require a minimum speed to prevent

Overheating

In addition to storing and releasing fluid, accumulators also

Absorb hydraulic shocks

In what part of the hydraulic reservoir tank does the sludge settle?

Sump

What is the reason for installing duplex in-line strainers in a hydraulic system?

Clean one while the other is operating