Hydraulic pumps & Actuator A

Question 1

non positive pump that has an impeller that throws the fluid away from inlet by centrifugal force

Answer 1

centrifugal or radial flow pump

Question 2

non positive pump which uses a propeller to move fluid axially from its inlet to the discharge

Answer 2

propeller pump

Question 3

amount of leakage in positive displacement pump

Answer 3

5-15%

Question 4

3 ways to change output of pumps

Answer 4

• use a flow control and relief valve built into discharge passage
• change the speed of the driver
• use a variable displacement pump

Question 5

4 types of piston pump

Answer 5

in line axial
bent axis
rotary piston
radial piston

Question 6

part of in line axial piston pump

carries the piston

Answer 6

rotating cylinder block

Question 7

part of in line axial piston pump

slides back and forth in the cylinder to take in and discharge fluid

Answer 7

piston

Question 8

part of in line axial piston pump

supports the piston and allow them to slide on the surface of the swash place

Answer 8

shoe

Question 9

part of in line axial piston pump

retracts the piston on the inlet stroke

Answer 9

retractor plate

Question 10

part of in line axial piston pump

stationary is set at an angle to the axis of the pistons that slide on its surface

Answer 10

swash plate

Question 11

part of in line axial piston pump

stationary and has ports that allow fluid to flow in and out of the cylinder

Answer 11

valve plate

Question 12

the output of a piston pump can be varied by controlling the length of the stroke, in line axial piston pumps can be adjusted by change the angle of this

Answer 12

swash plate

Question 13

axial piston pump

swashplate is supported by

Answer 13

yoke and pivots

Question 14

spring setting on load sensing pump

Answer 14

200-400 psi

Question 15

part of in line axial piston pump

pivots the yoke in needle bearing fitted in the case

Answer 15

pintles

Question 16

advantage of bent axis pump to axial piston pump

Answer 16

withstand high vacuum

Question 17

length of stroke on bent axis pump is based on

Answer 17

the angle between cylinder block and drive shaft

Question 18

how to stop flow of rotary piston pump

Answer 18

move reaction ring so its centre around the cylinder block

Question 19

component of rotary piston pump ports fluid in and out of the cylinder

Answer 19

pintle

Question 20

the flow of radial piston pump is pass through

Answer 20

the cylinder

Question 21

vane pump need to be sealed at the shaft at this end

Answer 21

drive end

Question 22

pumping elements of a vane pump

Answer 22

cam ring

rotor and vanes

Question 23

cam ring on the vane pump is eccentric

true or false

Answer 23

true

Question 24

unbalanced vane pump use a circular cam that is off centre

true or false

Answer 24

true

Question 25

the vanes are held against the cam in unbalanced vane pump by 2 forces

Answer 25

centrifugal force | hydraulic pressure

Question 26

balanced vane pump can be displaced by changing

Answer 26

the cam ring

Question 27

vane pump direction is determined by look at the pump from the

Answer 27

drive end

Question 28

when installing vanes, ensure that the trailing edge is on the side of the

Answer 28

feed notches

Question 29

orientation of rounded tipped vanes

Answer 29

either way

Question 30

swash plate control limits the maximum pressure in the system

Answer 30

pressure limiting compensator

Question 31

swash plate control regulates the flow to suit any given load

Answer 31

load sensing compensator

Question 32

moves swash plate to maximum angle in in-line axial piston

Answer 32

bias piston

Question 33

pump that has a cylinder block that rotates around a stationary shaft called a pintle

Answer 33

rotary piston pump

Question 34

how to increase stroke and flow in variable displacement rotary piston pump

Answer 34

moving reaction ring further off center

Question 35

difference between radial piston pump and piston pump

Answer 35

radial piston pump has stationary cylinder block

Question 36

vane pump with circular cam that is off center with respect to the rotor

Answer 36

unbalanced vane pump

Question 37

vane pump with ellipitical cam

Answer 37

balanced vane pump

Question 38

compact vane pump

Answer 38

balanced

Question 39

what determines amount of fluid displaced on each revolution in vane pump

Answer 39

thickness of cam ring | size of throws

Question 40

direction of rotation on vane pump is determined by what end

Answer 40

drive end

Question 41

trailing edge of vanes should be on this side

Answer 41

side of feed notches

Question 42

side rounded tip vanes need to be installed

Answer 42

any side

Question 43

bearings used on external gear pump to control radial loads

Answer 43

needle bearing

Question 44

gear on external gear pump with no axial thrust

Answer 44

herringbone

Question 45

gear on external gear with axial thrust

Answer 45

helical

Question 46

most quiet gear in external gear pump

Answer 46

herringbone

Question 47

advantage on internal gear pump

Answer 47

compact and quieter

Question 48

internal gear pump has less teeth on which gear

Answer 48

internal

Question 49

seal inside internal gear between inlet and outlet

Answer 49

crescent

Question 50

quietest gear pump and least dirt tolerant

Answer 50

geroter