working principles of pumps -...
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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)
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
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
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
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
27
Mechanical seals
Explain working , heat generation and
cooling techniques, flushing ,Cost and choice etc.
Mechanical seals
Seal types
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
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