1. PRINCIPLE & CONSTRUCTION OF HYDRAULIC PUMPS

2. HYDRAULIC PUMPS PRINCIPLE CHARACTERISTICS TYPES OF PUMPS
COMPARISON OF PUMPS
TROUBLE SHOOTING

3. PUMP - PRINCIPLE
THE PRINCIPLE OF A HYDRAULIC PUMP IS TO CONVERT MECHANICAL ENERGY INTO HYDRAULIC ENERGY.
THIS IS ACHIEVED BY GENERATING AN INCREASED VOLUME DURING INTAKE AND DECREASED VOLUME ON THE DELIVERY SIDE.

4. PUMP - PRINCIPLE Contd. VACUUM IS CREATED
PISTON MOVES OUT EXPANDING THE SPACE IN PUMPING CHAMBER
ATMOSPHERIC PRESSURE

5. PUMP CHARACTERISTICS PRESSURE RATING VOLUMETRIC EFFICIENCY NOISE LEVEL
FLOW RATING
PRESSURE RATING
VOLUMETRIC EFFICIENCY
NOISE LEVEL
CONTAMINATION LEVEL ALLOWED

6. TYPES OF PUMPS NON POSITIVE DISPLACEMENT PUMPS GEAR PUMP VANE PUMP
ROTARY
AXIAL PISTON
PUMP
RADIAL PISTON
RECIPROCATORY
POSITIVE

7. NON POSITIVE DISPLACEMENT PUMPS
EYE
INLET
OUTLET
DIFFUSER
OUTLET
IMPELLER BLADES
CENTRIFUGAL ( IMPELLER ) TYPES
IMPELLER
PROPELLER
AXIAL (PROPELLER ) TYPE
INLET

8. SINGLE VANE PUMP
To do this, flopping of the cam ring has to be done around the vertical axis. The vanes must also be repositioned in their slots so that their “leading edges” follow the direction of rotation.

9. SINGLE VANE PUMP SIDE PLATE DISCHARGE PORT DELIVERY VANE CAM RING
SHAFT
PRESSURE PLATE
ROTOR
SUCTION
SUCTION PORT
BOLT
Graphical Symbol

10. CARTRIDGE
SIDE PLATE
PRESSURE PLATE
CAM RING
BOLT
LOCATING PIN

11. VARIATION IN VANE PUMP DISPLACEMENT
ROTOR
CAMRING
“THROW”
WIDTH

12. BALANCED VANE PUMP OUTLET ROTATION ROTATION INLET CAMRING VANE INLET
ROTOR
INLET
DRIVE SHAFT

13. VANE PUMP - TYPICAL PUMP CHARACTERISTICS35
140
210
175
105 70 10 30 20 kW HP
Input Power
Output Flow
L/min 75 40 50 60
1200 r/min
1000 r/min
1500 r/min
1800 r/min
Pressure
Kgf / Cm2

14. VANE PUMP - TYPICAL PUMP CHARACTERISTICS
NOISE LEVEL
Noise Level [One metre (3.3 ft.) horizontally away from pump head cover]
1200 r/min
1000 r/min 35
140
210
175
105 70
Noise Level 60 55 50 45 65
dB(A)
Pressure
PV2R2-41
Kgf / Cm2

15. DOUBLE VANE PUMP SUCTION DELIVERY DELIVERY CARTRIDGE - 1 CARTRIDGE - 2
Graphic Symbol

16. EXTERNAL GEAR PUMP
OUTLET
DRIVEN GEAR
DRIVE GEAR
INLET

17. EXTERNAL GEAR PUMP
OUTLET
INLET

18. LOBE PUMP

19. INTERNAL GEAR PUMP

20. SINGLE PUMPS ROTOR VANE CAM RING DISCHARGE PORT WAVE WASHER SHAFT
PROPORTIONAL PRESSURE REDUCING VALVE
DISCHARGE PORT
WAVE WASHER
SHAFT
PRESSURE PLATE
SUCTION PORT
SIDE PLATE
Graphical Symbol

21. VARIABLE DISPLACEMENT VANE PUMPS
SIDE PLATE
PORT PLATE
RING
THRUST BLOCK
PRESSURE ADJ. SCREW
ROTOR-SHAFT
Graphical Symbol
FLOW ADJ. SCREW
GOVERNOR PISTON
DISCHARGE PORT
SUCTION PORT
DRAIN PORT

22. VARIABLE DISPLACEMENT VANE PUMPS
F p = Force Acting on Camring due to System Pressure
F S = Force due to Spring.
F t = Force acting on Thrust Block.
F p` = Force acting on Shaft Bearing. Q
Change in set
Pressure
PRESSURE
ADJUSTMENT
SCREW L
VOLUME
ADJUSTMENT
SCREW Q
Characteristics Q P
Change in set
Volume e
ECCENTRICITY
OF RING P
Eccentricity ( Max. )
Eccentricity ( Max. )

23. VARIABLE DISPLACEMENT PISTON PUMPS
SPOOL
FILLING PORT PLUG
DRAIN PORT
PRESSURE ADJ. SCREW
CONTROL PISTON
FLOW ADJ. SCREW
PIVOT
SHAFT
DISCHARGE PORT
Graphical Symbol
SUCTION PORT
YOKE
PISTON ASSEMBLY
SWASH PLATE
CYLINDER BLOCK

24. CYLINDER BLOCK ASSEMBLY
PIVOT
WASHER
SLIPPER RETAINER
CYLINDER BLOCK
PISTON ASSEMBLY
WASHER
PIN (3 pcs.)
SPRING
WASHER
RETAINING RING

25. CYLINDER BLOCK ASSEMBLY
PORT PLATE

26. VARIABLE DISPLACEMENT PISTON PUMPS
( AT FULL CUT - OFF )
PRESSURE COMPENSATOR TYPE .

27. VARIABLE DISPLACEMENT PISTON PUMPS PRESSURE COMPENSATOR CONTROL
SPOOL
OPERATING PISTON
PRESSURE ADJUSTMENT SCREW
YOKE
INLET
Discharge Cycle
DELIVERY ADJUSTMENT SCREW
OUT
Suction Cycle IN
OUTLET
Section A-A

28. VARIABLE DISPLACEMENT PISTON PUMPS PRESSURE COMPENSATOR CONTROL
OPERATING PISTON A
INLET
Discharge Cycle
OUT
Suction Cycle IN A
OUTLET
Section A-A

29. VARIATION IN PUMP DISPLACEMENT
NO STROKE
STROKE LENGTH
STROKE LENGTH
MAXIMUM SWASH
PLATE ANGLE
( MAXIMUM DISPLACEMENT )
DECREASED SWASH
PLATE ANGLE
( PARTIAL DISPLACEMENT )
ZERO SWASH
PLATE ANGLE
( ZERO DISPLACEMENT )

30. SWASH PLATE CAUSES PISTON TO RECIPROCATE
VALVE PLATE SLOT
PISTON SUB-ASSEMBLY
OUTLET PORT
DRIVE SHAFT
INLET PORT
SWASH PLATE
SHOE PLATE
CYLINDER BLOCK BORE

31. VARIABLE DISPLACEMENT PISTON PUMP - TYPICAL CHARACTERISTICS
Performance Characteristic Curve %
N=1500 r/min
100
Volumetric Efficiency
Overall Efficiency
Efficiency 80
L/min 60 30 HP 12 kW
Output Flow 8 20 10
Output Flow 8 6
Input Power
Input Power 6 4 10 4 2 2 40 80
120
160
Kgf/Cm2
Pressure

32. VARIABLE DISPLACEMENT PISTON PUMP - TYPICAL CHARACTERISTICSkW 12 10 4 2 6 8
Input Power HP 5 15 25
L/min
Output Flow 20 30
N=1500 r/min P=
140
120
100 80 60 40 7
P=Kgf / Cm2
Full Cut-off Power HP kW
2.0
1.5
1.5
1.0
Full Cut-off Power
1.0
1800 r/min
0.5
0.5
1500 r/min 40 80
120
160
Kg / Cm2
Full Cut-off Pressure

33. VARIABLE DISPLACEMENT PISTON PUMP - TYPICAL CHARACTERISTICS
Noise Level [One metre (3.3 ft.) horizontally away from pump head cover]
Drain
L/min
Full Cut-off
Full Flow
Pressure 80 40
160
120
dB(A) 50 60 70
Noise Level
N=1500 r/min
Kgf / Cm2
2.0
N=1800 r/min
1.5
Drain
Full Cut-off
1.0
N=1500 r/min
0.5
1500,1800 r/min
Full Flow 40 80
120
160
Pressure
Kgf / Cm2

34. BENT AXIS PISTON PUMP PISTON ROD UNIVERSAL LINK PISTON CYLINDER BLOCK
TO OUTLET
FROM INLET

35. COMPARISON OF HYDRAULIC PUMPS
TYPE
VANE PUMP
GEAR PUMP
PISTON PUMP
Working
Principle
Varying
Volume
between the
Vane &
Camring
Shifting
surrounded by
gear grooves &
casing.
Volume by
reciprocating
Pistons.
Average
Efficiency
High
Low except for
pressure
loading type.
Highest among
three types.
Wear &
Does not
decrease since
wearing of
camring or
vane can be
compensated
Decreases with
Wear

36. COMPARISON OF HYDRAULIC PUMPS

37. COMPARISON OF HYDRAULIC PUMPS

38. COMPARISON OF HYDRAULIC PUMPS

39. COMPARISON OF HYDRAULIC PUMPS
TYPE
PRESSURE
DISCHARGE
MAX. SPEED
OVERALL
EFFICIENCY
(Kgf/Cm 2 )
( L / min )
( rpm )
( % )
GEAR PUMP
20 ~ 210
7 ~ 570
1800~7000
75 ~ 90
VANE PUMP
2 ~ 950
2000~4000
AXIAL
PISTON
PUMP
70 ~ 350
2 ~ 1700
600 ~ 6000
85 ~ 95
RADIAL
50 ~ 250
20 ~ 700
700 ~ 1800
80 ~ 92

40. TROUBLE SHOOTING