Fluid Power Final

Question 1

Define fluid power

Answer 1

a type of system that uses energy to do work, by using a prime mover to drive a pump that presurizes a fluid, which is transferred through pipes & hoses to an actuator

Question 2

6 basic components in a hydraulic circuit.

Answer 2

reservoir/tank
pump
prime mover
actuator
valves
piping

Question 3

Reservoir?

Answer 3

holds oil

Question 4

Pump?

Answer 4

forces oil through system

Question 5

Prime mover?

Answer 5

drives pump by electric motor/other power source

Question 6

Valves?

Answer 6

control oil direction, pressure, and flow rate

Question 7

Actuator?

Answer 7

converts oil pressure to mechanical force/torque

Question 8

Piping?

Answer 8

carries oil

Question 9

Difference between a hydraulic system and a pneumatic system.

Answer 9

hydraulic - liquid
pneumatic - air

Question 10

List the 3 systems that use energy to do work.

Answer 10

mechanical, electronic, hydraulic

Question 11

Hydraulic v pneumatic actuator movement?

Answer 11

hydraulic more accurate

Question 12

Hydraulic v Pneumatic operating pressure?

Answer 12

Operating Pressure – hydraulic is more

Question 13

Hydraulic v Pneumatic actuator speed?

Answer 13

Actuator speed – hydraulic is less

Question 14

Hydraulic v pneumatic component weight?

Answer 14

Component weight – Hydraulic is heavier

Question 15

Hydraulic v pneumatic cost?

Answer 15

Cost – Hydraulic more expensive

Question 16

advantages of fluid power over mechanical power systems.

Answer 16

Remote control, complex mechanical lineages eliminated, instantly reversible motion, automatic protection & instant lubrication

Question 17

List the advantages of mechanical power systems over fluid power systems.

Answer 17

No oil leakage problems, no danger of bursting of hydaulic lines, no fire hazard

Question 18

Pascal’s Law?

Answer 18

Force on a confined fluid results in equal pressure in all directions

Force (lbs) = Pressure (psi) x Area (in^2)

Question 19

How to find Full Area?(cap side)

Answer 19

pi x diameter^2/4

Question 20

Annular Area?

Answer 20

Full area - Rod area

Question 21

Volume?

Answer 21

Area x stroke length (in^3)

Question 22

Extension force?

Answer 22

system pressure x full area

Question 23

Retraction force?

Answer 23

system pressure x annular area

Question 24

How to convert volume in cubic inches to gallons?

Answer 24

divide by 231

Question 25

pump output power?

Answer 25

pump output power (hp) = flow rate (gallons/min) x Pressure (psi)/1714

Question 26

the amount of energy required to lift 550 lbs one foot in one second

Answer 26

hp

Question 27

is the amount of work that can be done in a certain amount of time, or the Rate of work

Answer 27

power

Question 28

the force that tends to cause a rotation

Answer 28

torque

Question 29

the motion of a load through a distance in something useful being done

Answer 29

work

Question 30

defined as the ability to do work

Answer 30

energy

Question 31

3 types of positive displacement pumps

Answer 31

gear, vane piston

Question 32

Define displacement.

Answer 32

Volume of oil required for the motor shaft to turn 1 complete rotation

Question 33

Define Nominal flow rate

Answer 33

theoretical amount of oil supplied by the pump at a given rotation speed. Equal to 1 pump displacement multiplied by rotation speed

Question 34

Define slip value

Answer 34

Indicates the amount of oil that does not reach the pump output for a given increase in pump pressure.

Question 35

4 basic applications of accumulators

Answer 35

backup power, auxiliary power, hydraulic shock absorber, leakage compensator

Question 36

5 probable causes that should be investigated when actuator fails to move

Answer 36

bad actuator bad pump DCV fails to shift system pressure low actuator load is excessive

Question 37

4 advantages of hydraulic motors over electric motors

Answer 37

uni/bi directional instantly reversible absorb severe shock loading smaller & respond faster

Question 38

Hydraulic pumps create ______ not ___________

Answer 38

flow/pressure

Question 39

Resistance to _____creates _______

Answer 39

flow/pressure

Question 40

_______ determines actuator speed

Answer 40

flow

Question 41

___________determines actuator force

Answer 41

Pressure

Question 42

The speed of a hydraulic motor is a function of the circuit_____

Answer 42

flow

Question 43

The output force of a hydraulic motor is a function of the circuit _____

Answer 43

pressure