Pumps are used to add energy to fluids (gases, liquids, or slurries) in order to produce flow or increase pressure. They can perform many different functions, including moving a fluid from one location to another, recirculating a fluid in a closed system, such as in a heating or cooling system, and providing pressure, such as in hydraulic systems. These functions are performed primarily by two different types of pumps: centrifugal and positive displacement.

1. A DETAILED PRESENTATION ON PUMPS
BE MECH A
BATCH C
GROUP MEMBERS:
LAUKIK MORE
FELIX GEORGE
AMMAR QAZI
TANISH QUADROS

2. WHAT IS A PUMP?
Pumps are used to add energy to fluids (gases, liquids, or slurries) in
order to produce flow or increase pressure. They can perform many
different functions, including moving a fluid from one location to
another, recirculating a fluid in a closed system, such as in a heating or
cooling system, and providing pressure, such as in hydraulic systems.
These functions are performed primarily by two different types of
pumps: centrifugal and positive displacement.

3. INTRODUCTION ON PUMPS
• Usually pumps are used to transport or lift fluid from a lower level to
a higher level or through a certain distance
• It is a device that increases the pressure of the fluid so that fluid
transportation can be carried out. This increase in pressure is then
converted to potential energy as the liquid rises from lower position
to higher position.
• This is achieved by creating low pressure on suction side and high
pressure on delivery side.

4. CLASSIFICATION OF PUMPS
Primarily pumps are classified into two main categories
1. Positive displacement pumps
2. Dynamic pumps
Positive displacement pumps operate by filling and displacing liquid
from a cavity. Such pumps deliver a constant flow and volume of liquid
without discharge pressure or head. Positive displacement pumps are
ideal for a low flow–high pressure combination, and other application
niches.

5. CLASSIFICATION OF PUMPS
• Dynamic pumps include all types of pumps using fluid velocity and
the resulting momentum to pump and move the fluid through the
piping system.
• Although dynamic pumps usually have lower efficiencies than positive
displacement pumps, they require lower maintenance. They are also
capable of operating at high speeds and high fluid flow rates

6. SCHEMATIC REPRESENTATION OF CLASSIFICATION OF
PUMPS

7. RECIPROCATING PUMPS
A reciprocating pump is a class of positive-displacement pumps which
includes the piston pump, plunger pump and diaphragm pump. It is
often used where a relatively small quantity of liquid is to be handled
and where delivery pressure is quite large. In reciprocating pumps, the
chamber in which the liquid is trapped, is a stationary cylinder that
contains the piston or plunger.

8. ROTARY PUMPS
A rotary vane pump is a positive-displacement pump that consists of
vanes mounted to a rotor that rotates inside of a cavity. In some cases
these vanes can have variable length and/or be tensioned to maintain
contact with the walls as the pump rotates. Rotary pumps are capable of
pumping more fluid than reciprocating pumps of the same weight. A
number of types are included in this classification, among which are the
gear pump, the screw pump, and the moving vane pump. Unlike the
centrifugal pump, the rotary pump is a positive-displacement pump. This
means that for each revolution of the pump, a fixed volume of fluid is
moved regardless of the resistance against which the pump is pushing.

9. WORKING DIAGRAM OF A GEAR PUMP

10. CENTRIFUGAL PUMPS
Centrifugal pumps are used to transport fluids by the conversion of
rotational kinetic energy to the hydrodynamic energy of the fluid flow.
The rotational energy typically comes from an engine or electric motor.
The fluid enters the pump impeller along or near to the rotating axis and
is accelerated by the impeller, flowing radially outward into a diffuser
or involute chamber (casing), from where it exits.

11. AXIAL PUMPS
An axial flow pump has a propeller-type of impeller running in a casing.
The pressure in an AFP is developed by the flow of liquid over the
blades of impeller. The fluid is pushed in a direction parallel to the shaft
of the impeller, that is, fluid particles, in course of their flow through
the pump, do not change their radial locations. It allows the fluid to
enter the impeller axially and discharge the fluid nearly axially. The
propeller of an AFP is driven by a motor.

13. APPLICATIONS OF PUMPS
• Well pump
• Hand pump
• Sump pump

14. SUBMERSIBLE PUMPS
• A submersible pump (or sub pump, electric submersible pump (ESP)) is a device
which has a hermetically sealed motor close-coupled to the pump body.
• The whole assembly is submerged in the fluid to be pumped.
• The main advantage of this type of pump is that it prevents pump cavitation, a
problem associated with a high elevation difference between pump and the fluid
surface.
• Submersible pumps push fluid to the surface as opposed to jet pumps having to
pull fluids.

16. SELECTION CRITERIA
• Submersible pumps are chosen with consideration to pump type and application.
• The maximum discharge flow must be determined.
• Submersible pumps are also evaluated in terms of horsepower, a measurement of
mechanical energy.
• Discharge size of submersible pumps should be evaluated.

17. TYPES OF SUBMERSIBLE PUMPS
WELL PUMP
• A well pump is hung or
suspended in a water well on a
pipe, sometimes to depths past
1000’.
• Well pumps are powered by AC
(alternating current) voltage but
DC (direct current) voltage is
used on smaller pumps for low
flows of water up to a depth of
200 feet.
SUMP PUMP
• Sump pumps are used in a pit or
sump and sometimes just a lower
area like a swimming pull cover
or fountain.
• Sump pumps are usually AC
powered but smaller bilge pumps
for boats can be DC voltage.

19. PRESSURE RECUPERATING DEVICES
• Also known as Pressure Exchangers.
• A pressure exchanger transfers pressure energy from a high pressure fluid stream
to a low pressure fluid stream.
• Efficient type of pressure exchanger is a rotary pressure exchanger.
• The performance of a pressure exchanger is measured by the efficiency of the
energy transfer process and by the degree of mixing between the streams.
• The energy of the streams is the product of their flow rates and pressures.

20. APPLICATION
REVERSE OSMOSIS

21. AXIAL AND RADIAL THRUST IN CENTRIFUGAL PUMPS
During operation and working of centrifugal pumps, the kinetic energy of
flowing liquid is converted into pressure energy. This high pressure liquid is
continuously flowing all over the circumference of the impeller and also gets
entrapped inside the clearances between impeller and casing / casing cover.
This high pressure liquid exerts pressure on the outlet passages and shrouds
of the impeller resulting in generation of two thrusts’
1) Axial Thrust: The force generated in longitudinal direction on account of
different areas of impeller exposed to trapped pressurized liquid called as
axial thrust.
2) Radial Thrust: The force generated in lateral direction is due to dissimilar
pressure generation in volute and is called as Radial thrust.

22. AXIAL THRUST
• Axial thrust arises in the centrifugal pumps
due to their asymmetry.
• The clearances between casing cover and
impeller back shroud, casing and impeller
front shroud are filled with fluid at delivery
pressure. This pressure acts on the impeller
shrouds.
• As the back shroud is having larger surface
area than front shroud, a net thrust acts on
the impeller in the direction opposite to that
of the incoming flow.
• The force contributed by the change in the
momentum of incoming flow is to be
considered

23. The resultant unbalanced axial thrust is vector summation of the following forces :
1) Force acting on front shroud due to liquid of delivery pressure entrapped between pump casing and
front shroud. (F1)
2) Force acting on back shroud due to liquid of delivery pressure entrapped between casing cover and
back shroud. (F2)
3) Force acting in the direction of the liquid flow due to its momentum change. (Fm)

24. METHODS TO BALANCE AXIAL THRUST
1) Use of ball bearings
It is provided in the direction of the axial thrust to balance it.

25. 2) Providing balancing holes:
The provision of balancing hole in the impeller causes the suction pressure to act
equally from both the sides.From 10 to 25 per cent of the axial thrust always remains
depending on the size of the holes

26. 3) Balancing with radial back vanes
In this method, radial ribs are used on the back shroud to reduce the pressure in the space
between the impeller, and the pump casing. The impeller housed inside pump casing and
the radial back vanes provided at the back shroud of the impellers acts as auxiliary impeller
which restricts the entry of liquid into the clearances between impeller back shroud and
casing cover.

27. RADIAL THRUST
The hydraulic radial load is due to the unequal velocity of the fluid flowing through the casing.
The unequal fluid velocity results in a non-uniform distribution of pressure acting on the
circumference of the impeller. The radial load is most influenced by the design of pump casing.
The pump casing is designed to direct the fluid flow from the impeller into the discharge
piping.

28. METHOD TO BALANCE RADIAL THRUST
Double Volute Casing:
Radial thrust can be minimized by making double volute casing.
To avoid failure of shafts due to high radial loads pumps were designed with heavy shafts
but these are uneconomical

29. TROUBLESHOOTING IN CENTRIFUGAL PUMPS
Contents:
Pump leaks.
No flow or low flow.
Noise and/or vibration is noticeable.

30. Pump Leaks
 Whenever leakage is encountered and before removing your pump, determine
when the leakage is occurring… while running, or while not running.
 During these inspections you should try to determine the exact origin of the leak.
 Special attention should be given to the shaft sleeve.
 Once you have determined when the pump is leaking, refer to the guide below.

39. Thank You