It is an introdutory level presentation on hydraulic pumps and motors.

1. Hydraulic pump and motor
Prepared by:
Hamza Nawaz
CU-369-2017
Supervisor:
Sir Sadiq Ali
CECOS University of IT and Emerging Sciences
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2. Contents
 Fluid machines
 Types of pumps, compressors, fans or blowers
 Types of turbines and motors (actuators)
 Hydraulic pumps
 Hydraulic motors
 Applications of hydraulic pumps and motors
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3. Fluid machines
 Devices that either perform work on or extracts work (or power) from a fluid.
 Fluid machines may be broadly classified as
Based on Principle of Operation,
1. Positive displacement
2. Dynamic
Based on Direction of Energy Conversion,
1. Turbines and motors
2. Pumps, compressors, fans or blowers
Based on Fluid Used,
1. Hydraulic
2. Gas or pneumatic
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4. Positive displacement machines (Hydrostatic)
 Energy transfer is accomplished by volume changes that occur due to movement
of the boundary in which the fluid is confined.
 Energy transfer is accomplished by relative motion between the fluid and the
moving part of the machine.
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5. Turbines and motors (actuators)
 Machines that extract energy from a fluid in the form of
work (or power) are called turbines and motors.
 Machines that add energy to a fluid by performing work on
it are called pumps, fans, blowers, or compressors.
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6. Hydraulic
 Machines that either add energy to or extracts energy from
a liquid are called hydraulic machines.
 Machines that either add energy to or extracts energy from
a gas (commonly air) are called pneumatic machines.
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7. Types of pumps, compressors, fans or blowers
Hydraulic Gas or pneumatic
Reciprocating
1. Piston pumps
2. Plunger pump
3. Diaphragm pump
Compressors
Reciprocating
1. Piston compressors
2. Diaphragm
Rotary
1. Scroll
2. Vane
3. Lobe
4. Screw
5. Liquid ring
6. Centrifugal
7. Axial
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8. Types of pumps, compressors, fans or blowers
Hydraulic Gas or pneumatic
Rotary
1. Lobe pump
2. Peristaltic pump
3. Gear pumps
4. Rotary vane pump
5. Screw pump
6. Progressive cavity pump
7. Centrifugal pump
Fans
1. Centrifugal
2. Axial
Blowers
1. Centrifugal
2. Positive displacement
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9. Types of turbines and motors (actuators)
Hydraulic Gas or pneumatic
Turbines
Impulse Turbines
1. Pelton turbine
2. Turgo turbine
3. Cross flow turbine
Reaction Turbines
1. Francis turbine
2. Kaplan turbine
Gravity Turbines
1. Archimedian screw turbine
2. Water wheel
Turbines
1. HAWT
2. VAWT
3. Gas turbine
Motors
Reciprocating
1. Cylinders or jacks 9

10. Types of turbines and motors (actuators)
Hydraulic Gas or pneumatic
Motors
Reciprocating
1. Cylinders or jacks
Rotary
1. Gear motors
2. Vane motor
3. Piston motors
Rotary
1. Vane motor
2. Gear motors
3. Piston motors
4. Turbine motors
5. V-type motor
6. Diaphragm motors 10

11. Plunger pump
Construction
 Unlike a tight fitting piston a plunger fits loosely in the cylinder.
Working
 The physical mass of the plunger alters the size of the chamber and displaces
the fluid.
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12. Triplex plunger pump animation
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13. Axial piston pump
Construction
 It is composed of a casing, shaft, cylinder block, pistons (plungers), swash plate, valve
plate, regulator and other components.
Working
 As the shaft rotates the pistons stroke along the swash plate sucking and delivering
hydraulic oil.
 The delivery flow can be adjusted by altering the angle of swash plate.
 The delivery flow is controlled by the regulator in variable displacement pumps.
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14. Axial piston pump animation
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15. Peristaltic pump
Construction
 They consist of a flexible tube and external rotating rollers or linear fingers on a rotor.
Working
 The rollers, attached to the rotor compresses the flexible tube.
 As the rotor turns, the part of the tube under compression is closed forcing the fluid to be
pumped through the tube.
 Additionally, as the tube opens to its natural state after the passing of the roller fluid flow is
induced to the pump. This process is called peristalsis.
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16. Peristaltic pump animation
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17. Radial piston motor
Construction
 There are many designs for radial piston motors.
 One design have radial cylinders each in a separate block.
 The pistons are connected to the shaft by a crank.
Working
 Suitable valve design allow the oil into the cylinders and force the pistons to
reciprocate and turn the shaft.
 These produce high power and torque. 17

18. Radial piston motor animation
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19. Vane motor
Construction
 The rotor has slots in it for sliding vanes pushed by springs to the inside wall of
the circular housing forming a sealed chamber.
Working
 Flow from the pump enters the inlet , forces the vanes to rotate and passes out
through the outlet.
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20. Vane motor animation (Motor works opposite)
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21. Gear motor
Construction
 It also has a number of designs.
 Consists of two gears meshed together inside an oval housing.
Working
 Fluid is pumped into the motor inlet , where it has two courses to follow between the
inner surface of oval housing and gear teeth.
 The fluid drives both the gears but only one gear is coupled to the output shaft. 21

22. Gear motor animation (Motor works opposite)
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23. Hydraulic pumps and motors evaluation formulas
Flow power
𝑄 = 𝑛 ∙ 𝑉𝑠𝑡𝑟𝑜𝑘𝑒 ∙ 𝜂 𝑣𝑜𝑙
Where
Q = flow (m3/s)
𝑛 = stroke frequency (Hz)
𝑉𝑠𝑡𝑟𝑜𝑘𝑒 = stroked volume (𝑚3
)
𝜂 𝑣𝑜𝑙, volumetric efficiency
𝜂 𝑣𝑜𝑙 =
𝑄𝑡ℎ𝑒𝑜𝑟𝑎𝑡𝑖𝑐𝑎𝑙
𝑄 𝑎𝑐𝑡𝑢𝑎𝑙
𝑃 =
𝑛 ∙ 𝑉𝑠𝑡𝑟𝑜𝑘𝑒 ∙ ∆𝑝
𝜂 𝑚𝑒𝑐ℎ
Where
P, power (W)
𝑛 = stroke frequency (Hz)
𝑉𝑠𝑡𝑟𝑜𝑘𝑒 = stroked volume (𝑚3)
∆𝑝 = pressure difference over pump
(Pa)
𝜂 𝑚𝑒𝑐ℎ = mechanical efficiency
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24. Hydraulic pumps and motors evaluation formulas
Mechanical efficiency Hydraulic efficiency
𝜂 𝑚𝑒𝑐ℎ =
𝑇𝑡ℎ𝑒𝑜𝑟𝑎𝑡𝑖𝑐𝑎𝑙
𝑇𝑎𝑐𝑡𝑢𝑎𝑙
∙ 100%
Where
𝜂 𝑚𝑒𝑐ℎ = mechanical efficiency percentage
𝑇𝑡ℎ𝑒𝑜𝑟𝑎𝑡𝑖𝑐𝑎𝑙 = theoretical torque to drive
𝑇𝑎𝑐𝑡𝑢𝑎𝑙 = actual torque to drive
𝜂ℎ𝑦𝑑𝑟 =
𝑄 𝑎𝑐𝑡𝑢𝑎𝑙
𝑄𝑡ℎ𝑒𝑜𝑟𝑎𝑡𝑖𝑐𝑎𝑙
∙ 100%
Where
𝜂ℎ𝑦𝑑𝑟 = hydraulic efficiency percentage
𝑄𝑡ℎ𝑒𝑜𝑟𝑎𝑡𝑖𝑐𝑎𝑙 = theoretical flow rate
output
𝑄 𝑎𝑐𝑡𝑢𝑎𝑙 = actual flow rate output
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25. Applications of hydraulic pumps and motors
1. Manufacturing industries
2. Mining industry
3. Construction industry
4. Agriculture industry
5. Transportation industry
6. Military
7. Energy (including renewable) 25

26. Questions are welcome
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27. Thanks
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