Hydraulics

Question 1

What are the two types of actuators

Answer 1

Linear and rotary

Question 2

What is the force trying to stop a body from moving

Answer 2

Resistance

Question 3

When dealing with energy what do you have to watch out for

Answer 3

The state or condition in which it was found

Question 4

What is process to reduce friction between two moving parts

Answer 4

Lubrication

Question 5

What is the force that causes movement over a distance

Answer 5

Work

Question 6

What does SUS stand for

And what is it measuring

Answer 6

Saybolt universal seconds

Viscosity

Question 7

How does a flow control valve work

Answer 7

Operates by resistance

Question 8

What does ASTM stand for

Answer 8

American society for testing materials

Question 9

What is the resistance of molecules sliding/moving past eachother

Answer 9

Viscosity

Question 10

Common fluids used in a hydraulic system are:

Answer 10

Paraffinic and naphthalenic

Question 11

The law of conservation states:

Answer 11

That energy can not be created nor destroyed although it may change from 1 form to another

Question 12

When a volume of fluid flows through tubing with a given amount of time

Answer 12

Flow rate

Question 13

An actuator converts hydraulic working energy into:

Answer 13

Mechanical energy

Question 14

Varnish, lacquer and sludge are formed by:

Answer 14

High temperature oxidation

Question 15

Presents of ____ in a hydraulic fluid can plug sensing orifices, cause moving parts to stick and wear excessively and act as a catalyst to oxidize oil.

Answer 15

Dirt

Question 16

A high pressure line with a pinhole leak spraying an oil mist into the air is:

Answer 16

Combustible

Question 17

Fire resistant fluid that is close to petroleum oil is:

Answer 17

Synthetic

Question 18

If a pump is filled with liquid it is:

Answer 18

Primed

Question 19

What component is designed to store fluid l, allow entrained air to escape and also dissipate heat?

Answer 19

Reservoir

Question 20

At sea level one column of air, one sq inch weighs:

Answer 20

14.7 psi

Question 21

T or F

Cavitation destroys metal surfaces and interferes with viscosity

Answer 21

False

Question 22

T or F

Hydropneumatic accumulators in industrial systems use nitrogen.

Answer 22

False

Question 23

T or F

Generation of heat by working energy traveling through a system to a point of work is system incompatibility

Answer 23

False

Question 24

T or F

Major causes of air entrainment is leakage past the piston seals.

Answer 24

False

Question 25

T or F | Pressure compensated past flow control vlvs are designed to meter pressure changes ahead or after orifice

Answer 25

True

Question 26

T or F | Main pump with pressure compensator causes pump discharge to reduce when pressure increases

Answer 26

True

Question 27

T or F | The sump strainer is on the return side

Answer 27

False

Question 28

T or F | A pressure filter is in the circuit between the pump and system components

Answer 28

True

Question 29

T or F | A flow control valve should be installed in the system to restrict fluid as it flows to the actuator

Answer 29

False

Question 30

T or F The flow path through a normally closed pressure reducing valve is one when fluid exerts enough pressure to counteract vlv spring pressure

Answer 30

True

Question 31

T or F | In double acting single rod cylinder the extending stroke is faster than the return stroke

Answer 31

False

Question 32

Liquid enters and is forced out of pump by?

Answer 32

Generating an increase and decrease of volume out of housing

Question 33

The main function of hydraulic fluid is transferring power and:

Answer 33

Lubricating the internal surfaces of components

Question 34

Dirt comes in all shapes and sizes and can enter the hydraulic system by:

Answer 34

Dirt built into the system, generated within the system, and added to the system

Question 35

What is the most popular kind of piston pump

Answer 35

Axial piston pump

Question 36

In a vane pump, if there’s an unbalance with more pressure on one side it cause:

Answer 36

Excess stress on drive shaft and bearings

Question 37

Variable displacement pumps can vary output by?

Answer 37

Adjusting the squash plate, Cary position of cam ring and changing the size of fluid chambers

Question 38

What type of piston pump do the pistons in one half of the circle of rotation generate an increase in volume and in the other half of rotation the pistons generate a decrease in volume

Answer 38

Axial piston pump

Question 39

Which component is designed to store hydraulic fluid at system pressure and release when the system demand is higher then pump delivery.

Answer 39

Accumulator

Question 40

Cylinder pistons have 3 different kind of positive seals:

Answer 40

Lip seal, cast iron piston rings and single bidirectional element

Question 41

Why is entrained air a sealing problem with a hydraulic system

Answer 41

Pseudo cavitation

Question 42

In hydraulic motors the torque required to move the load is:

Answer 42

Breakaway torque

Question 43

What can cause the pump to not start and block fluid flow

Answer 43

Improperly maintained or sized sump strainer

Question 44

What vlv reduces pressure changes beyond the vlv

Answer 44

Normally open pressure reducing vlv

Question 45

A normally non passing control vlv which causes one operation before another is a:

Answer 45

Sequencing vlv

Question 46

2 common scales measuring pressure?

Answer 46

Psig and psia

Question 47

What type of pressure reducing vlv should prevent a cylinder from dropping a heavy load

Answer 47

Counterbalance vlv

Question 48

Which cylinder component prevents piston from slamming against end caps on end of each stroke €===3

Answer 48

Cushions

Question 49

A ____ type pump can be a variable displacement pump?

Answer 49

Piston

Question 50

2 classifications of positive displacement pumps

Answer 50

Variable or fixed

Question 51

Which directional control vlv is used for a single acting cylinder

Answer 51

2 position 3 way

Question 52

What are the 3 types of reservoirs

Answer 52

Overhead, L-shaped and conventional

Question 53

What directional control valve is used when controlling a 1 directional hydraulic motor on or off

Answer 53

2 way 3 position

Question 54

What control vlv is used for 1 direction with a pilot line

Answer 54

Pilot operated check vlv