1

Working principles

of pumps

History of Reciprocating pumps

In 17th century Egyptians in Alexandria built reciprocating fire pump and and it had all the parts of today’s pump.

About 1805 Newcomen (Great Britain) built a reciprocating pump using steam engine as the driver.

He was the first man to use seam for driving purposes.

In 1840-50 Worthington (U.S.A) developed a steam engine driven pump.

Then many developments came.

2

History of Centrifugal pumps pumps

The inventor ca not be name with assurance.

In the 17th century Jordan, an Italian had made some drawing of a centrifugal pumps.

In the early 18 century French physicist Papin built a centrifugal pump of primitive design.

In 1732 Demouir pumps was put on service in France,

In 1818 Andrews ( USA) built a single stage centrifugal pump.

Then many developments came in the industry...

History of best pump

Human heart.

Everybody knows Who invented.

3

100

Bar

200

meters

M

Pumps are used to move liquids

•from a lower pressure system to higher pressure

•From a lower elevation to higher elevation

•From one place to another place at different/same elevation and pressure.

10 kms

100

Bar

10

kms

200

meters

M

Pumps add pressure energy to over come

elevation needs ( potential energy)

Frictional losses

Delta pressure requirements

Energy needed for pumps= volumetric flow*pressure

4

Po

we

r re

qu

ire

d f

or

pu

mp

ing

Power = mass X dynamic head

Power ( kW)= H Q r/367000

H = Total head in meters Q=Flow M3/H

r=Density in Kg/M3

Power ( kW)= H Q r/35.99

H = Total head in barA Q= Flow M3/H

r=Density in Kg/M3

Please refer Perry

Pleased divide by efficiency for actual power

How to give energy ?

Centrifugal force

(throwing)

Positive displacement

(physically pushing)

5

Centrifugal pumps

Working principles centrifugal pumps

6

Parts of a centrifugal pump

1. Impeller

2. Casing

3. Eye

4. Seal/packing

5. Wear ring

Ad

va

nta

ges

of

ce

ntr

ifu

gal p

um

ps

1. It simple and easy to construct. Available in different

materials .

2. Absence of valves. Less maintenance.

3. High rpm design. Can be coupled to a motor directly.

4. Steady delivery.

5. No damage in delivery is blocked.

6. Smaller in Size when compared to reciprocating type

for the same capacity.

7. Can handle slurries.

7

Dis

-Ad

va

nta

ges

of

ce

ntr

ifu

gal p

um

ps

1. For high pressure we need multistage pump which

are complex to construct.

2. Efficiency is high only over a range.( explain graph)

3. Usually not self priming

4. Non return valve is needed in the delivery to avoid

back flow.

5. Very viscous fluid can not be handled/

Types centrifugal pumps

Typical classification

• Single stage

• Multistage

Explain why and how

8

Sin

gle

sta

ge

M

ult

i s

tag

e

Multistage pumps are used to limit rpm and whenever we

have high DP. Example BFW pumps.

9

Thrust balance centrifugal pumps

1. Double suction pumps

2. Thrust balance in multistage pumps

Stage arrangement

3. Thrust balance line and thrust disk and bearing

Double suction pumps

Sea water

10

Double suction pumps 323-J UREA

Multistage pumps

Thrust balance in a multi-stage pump

11

Multistage BFW Pump Ammonia

Multistage pumps

Thrust balance in a multi-stage pump

Explain the principle of balance disc

Thrust balance line and caution

In Out

12

Multistage pump

Explain thrust balance

Positive displacement

pumps

13

Positive displacement pumps

• Reciprocating

• Rotary

Reciprocating Pumps

• Piston type

Vertical& Horizontal & double acting

• Plunger type

• Diaphragm pump

14

Reciprocating pumps

Explain double acting, plunger

type , vertical, horizontal,

multistage

Diaphragm pumps

15

Diaphragm pumps

Diaphragm Reciprocating pumps

Basic principle is similar to a reciprocating plunger pump/

Plunger pressurizes the hydraulic oil which when pressurized pushes the

diaphragm and discharge starts.

Stroke length can be adjusted and hence the dosing flow rate.

No direct contact of plunger with the solution.

Direct contact is only with diaphragm ( neoprene, Teflon etc)

16

Dia

phra

gm

Rec

ipro

cati

ng p

um

ps

Figure 1: The air valve directs pressurized

air to the back side of diaphragm "A". The

compressed air is applied directly to the

liquid column separated by elastomeric

diaphragms.

The compressed air moves the diaphragm

away from the center block of the pump. The

opposite diaphragm is pulled in by the shaft

connected to the pressurized diaphragm.

Diaphragm "B" is now on its air exhaust

stroke; air behind the diaphragm has been

forced out to atmosphere through the

exhaust port of the pump. The movement of

diaphragm "B" toward the center block of

the pump creates a vacuum within the

chamber "B". Atmospheric pressure forces

fluid into the inlet manifold forcing the inlet

ball off its seat. Liquid is free to move past

the inlet valve ball and fill the liquid

chamber.

Dia

phra

gm

Rec

ipro

cati

ng p

um

ps

Figure 2: When the pressurized

diaphragm, diaphragm"A", reaches the

limit of its discharge stroke, the air valve

redirects pressurized air to the back side

of diaphragm "B". The pressurized air

forces diaphragm "B" away from the

center block while pulling diaphragm

"A" to the center block. Diaphragm "B"

forces the inlet valve ball onto its seat due

to the hydraulic forces developed. These

same hydraulic forces lift the discharge

valve ball, forcing fluid flow to flow

through the pump discharge. The

movement of diaphragm "A" to the

center block of the pump creates a

vacuum within liquid chamber "A".

Atmospheric pressure forces fluid into

the inlet manifold of the pump. The inlet

valve ball is forced off its seat allowing

the fluid being transferred to fill the

liquid chamber.

17

Diaphragm Reciprocating pumps

Figure 3: Upon completion of the

stroke, the air valve again redirects air

to the back side of diaphragm "A", and

starts diaphragm "B" on its air exhaust

stroke. As the pump reaches its original

starting point, each diaphragm has

gone through one air exhaust or one

fluid discharge stroke. This constitutes

one complete pumping cycle. The pump

may take several cycles to become

completely primed depending on the

conditions of the application.

Gear and screw pumps

•High pressure and viscous fluids

•Used in Samd for lube and seal oil

pumps air booster of ammonia, 102-J

18

Gear pumps

•High pressure and viscous fluids

Example : lube/ seal oil pumps

See the solution is pushed out

of the pump physically

19

Only one gear is used ( Explain)

Screw pumps

•High pressure and viscous fluids

Example : lube/ seal oil pumps

20

SCREW PUMP

Talk about selection, parallel operation, reverse running etc.

SCREW PUMP

21

SCREW PUMP

Talk about selection, parallel operation, reverse running etc.

SCREW PUMP

Talk about selection, parallel operation, reverse running etc.

22

Sealing in pumps

Sealing in pumps

Fixed sealing – Packing

Centrifugal and reciprocating

Rotating – Mechanical seal

Centrifugal, gear pumps etc

23

Gland Packing Im

pel

ler

Stuffing box

Gla

nd

pac

kin

g p

rin

cip

les

Explain packing stuffing box , heat generation and

cooling techniques. , Lantern rings ,flushing ,Cost and choice etc.

24

Pac

kin

g

Explain packing stuffing box , heat generation and

cooling techniques. , Lantern rings ,flushing ,Cost and choice etc.

Pac

kin

g

25

Mechanical seal Im

pel

ler

1

2

3

Fixed Rotating

Three sealing points of a mechanical seal ( 1,2, and 3)

Stuffing box

26

Mechanical seals

Mechanical seals

27

Mechanical seals

Explain working , heat generation and

cooling techniques, flushing ,Cost and choice etc.

Mechanical seals

Seal types

28

Mechanical seals

Mechanical seals

29

Dou

ble

sea

ls –

Haza

rdou

s li

qu

ids

Explain need, sealant glycol, flushing etc.

Special Magnetic seals for hazardous/ expensive / corrosive fluids

30

Submersible pumps

Self-priming as they are inside the liquid.

Lube oil consoles , sump tanks, hazardous solution pumping etc.