1. M.S.STEVE
Assistant Professor
Dept. of Mechanical Engineering
Amal Jyothi College of Engineering, Kanjirapally.
Email: (mssteve@amaljyothi.ac.in)
Phone: +91 9745917858

2. A pump is a machine which converts mechanical energy to fluid energy, the
fluid being incompressible.
This action is opposite to that in hydraulic turbines.
Based upon the working principle pumpa can be classified as
Amal Jyothi College of Engineering, Kanjirapally

3. Centrifugal pump
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4. Centrifugal Pump

5. Amal Jyothi College of Engineering, Kanjirapally

6. Working Of Centrifugal Pump
• Basically consist of three main stages
1. Priming- filling the suction pipe and the entire casing with
water to develop required suction head
2. Developing required suction head by the centrifugal force
produced by impeller
3. Producing required discharge head
 By increasing kinetic energy of water with impeller
 Converting kinetic energy to pressure energy with the
help of involute casing
Amal Jyothi College of Engineering, Kanjirapally

7. Centrifugal Pump…..a short look
 Initial process to be done is priming of pump.
 The presence of foot valve(non return valve) helps to retain the
water in pump when it is stopped
 In pumps, the movement of blade system(impeller) moves the
fluid, which is always in contact with blade thereby converting
mechanical energy of blade system to kinetic energy
 So the centrifugal head imparted to the fluid by its rotation
enables the liquid to reach at higher level
 The increase in cross sectional area of casing towards the
delivery pipe helps to convert the kinetic energy of water to
required pressure energy
 For perfect conversion, the moving blade should be in contact
with the fluid at all places. In other words, the moving blade
system should be completely immersed in fluid.
Amal Jyothi College of Engineering, Kanjirapally

8. Positive Displacement pump
 In positive displacement pumps, fluid is pushed whenever pump runs. The
principle of action is the actual displacement or pushing of liquid by piston
plunger etc.
 These pumps are also called as ‘static pumps’. The pumps, operated under
this principle, are reciprocating, screw, ram, plunger, gear etc.
 The volume of liquid delivered is constant regardless of the pressure and is
varied only with the variation in the speed of the running motor
Amal Jyothi College of Engineering, Kanjirapally

9. Positive Displacement pumps
Lobe pump
Reciprocating pump
Rotary Gear pump
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10. Reciprocating Pump
• Components
 Suction and delivery pipe with unidirectional valves,
 Cylinder piston arrangement,
 Connecting rod and crank mechanism
• Working
 Suction stroke-backward movement of piston creates vacuum
inside cylinder causing the water to come in
 Discharge stroke- forward movement of piston pushes the water
to discharge pipe
Amal Jyothi College of Engineering, Kanjirapally

11. Reciprocating Pumps