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SUBMITTED BY:-
PARUL GARG
ROLL NO.D-5104
ECE DEPARTEMENT
SUBMITTED TO:
DEPTT. OF ELECT & COMM.
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First it was to be set up at G.N.D.T.P. but air forcepersonal restricted it & it was shifted to 22km apartfrom Bathinda city & named as GURU
HARGOBIND THERMAL PLANT. Its purpose is to produce electricity.
The factors favoring the installation are:-
To fulfill power demand.
Low initial cost & low generation period ascompared to hydroelectric generating center.
Good railway connection.
It meets 20-25% of power requirements in Punjab.
Companies involved are TATA HONEYWELL &BHEL.
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Total no. of units are four & forth is standby.
First two units are commenced in 1990s &210MW electricity is generated by each unit.
Third unit is commenced on 14 April 2008 &produces 250MW electricity.
Fourth unit is still standby as commencement offourth unit is waited in July & it will produce250MW electricity.
Its overall cost is 35 crores.
Its overall efficiency is 95%.
It distributes power from Barnala Sub distributionMansa, Bathinda, Delhi, Ludhiana as per
requirement.
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COAL HANDLING
SYSTEM
CWSYSTEM
TURBINE AND
GENERATOR
SECTIONBOILER SECTION
CONDENSATION
CYCLE
STEAM
ELECTRICITY
ASH HANDLING
SYSTEM
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MILLS
The coal in pulverized state does not get burntin boiler so coal from rail wagon is sent to millswhere it is crushed & formed into form which canbe used in boiler.
Its operating parameters are:-
Designed air flow per mill is 53.89 tons/hr.
Recommended mill outlet temperature is 85C ,ifbelow 60-80C then it may not dry the coalsufficiently and may cause choking.
If temperature exceed from 95C then it leadto mill on fire.
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PRIMARY AIR FANSFirstly for crushing of coal in mills hot air isprovided by PA fans.
Secondly the coal from mills in powder form is
pushed to boiler furnace with the help of hotout steam supplied by PA fans.
Number of fans are two per boiler.
Its capacity is 70 cubic meter/sec.
Its fan speed is 1480 R.P.M.
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FORCED DRAUGHT FANS
For combustion of fuel, air is required which iscalled as secondary air and it is provided by
FD fans.Number of fans are two per boiler.
Its capacity is 110 cubic meter/sec.
Its fan speed is 1480 R.P.M.
INDUCED DRAFT FAN
It is used to suck the gases out of the furnace& throw them into the stack . The temperature
at which it work is 125-250 degree centigrade. Number of fans are three per boiler.
Its capacity is 230 cubic meter/sec.
Its fan speed is 980 R.P.M.
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TURBINE & GENERATOR
There are three turbines & a generator havingcommon shaft.
When steam from boiler falls on blades ofturbine then turbine & generator rotatesresulting in production of electricity.
Its rated output is 210MW.Its rated speed is 3000 R.P.M.
Inlet steam pressure is 150kg/cm2.
Inlet steam temperature is 535 degreecentigrate.
Weight of turbine is 475t approximately.
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CONDENSATE CYCLE
Steam after doing the useful work in turbine &generator comes to condenser for cooling & can be
reused in the process. Then it is pumped todeareater by CEP through different heating stages& these are:-
GLAND STEAM COOLER
DRAIN COOLERLP HEATERS
HP HEATERS
The approximate temperature rise of condensateafter passing through above heating stages is from40/45 at hot well to 166C at the deaerator ( at fullload).
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GLAND STEAM COOLER
Its basic purpose is to increase the temperature
of water. It increases the temperature by 2degree centigrade.
It is single pass heat exchanger & having tubes
which condensate the water.
Number of zigzag shaped tubes are 313.
Material used for tubes is stainless steel.
LP HEATERS
After passing from GSC it goes to LP heaters
Where temperature increases.
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DRAIN COOLER
If temperature of water rises beyond in LP
heaters then water goes to this & it decreasesthe temperature.
There are 510 straight tubes & material used
for it is Brass.
Material for tube plate & shell is Carbon Steel.
Tubes surface area is 35m .
Water passing from here goes to LP heaters &
HP heaters and goes to dearator.
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DEARATOR
The water coming from drain cooler
contain certain gases like carbon dioxide,oxygen, ammonia etc.
So this water cannot be reused forprocess of plant.
So to prevent from internal corrosion weuse DEARATOR.
Its design temperature is 250 C & it
operate at 170 C.
Its design pressure is 7.4 Kg/cm & itoperate at 6.8 Kg/cm.
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BOILER FEED PUMP
It is the important auxiliary of the powerhouse.
It takes supply of water from Dearator &
supply to boiler drum.
Pump type is FK6D30.
Its direction of rotation is anti clockwise.
Its input power is 3008.8kw.
Its speed is 5145 R.P.M.
Its efficiency is 82%.
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INTRODUCTION
In every process industry there are so manyparameters like pressure, temperature, flow,
level etc that are to be measured & controlled.
So measurement system is required to measure
all these parameters. Operation of measurementsystem can be described in terms of functional
elements which are as follow:-
Primary sensing element Variable conversion element
Data presentation element
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The primary sensing element is the most
important part of the measurement system. It
includes a sensor & a transducer.
Sensor is a device that detects a measurand orquantity to be measured.
Its output goes to transducer.
Transducer converts signal into electrical signal.
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Depending upon the quantity to be
measured different types of sensors are:-
Pressure sensors
Flow sensors
Temperature sensors
Level sensorspH sensors
SENSORS
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PRESSURE SENSORS
Pressure measurement is most important
industrial measurement.
Its principle is applied in other
measurement like temperature, flow, liquid
level.
Pressure =force/area, N/m2.
It has same unit as stress.
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Pressure can be measured as absolute, gauge ,
differential pressure.
Absolute pressure is the absolute value of theforce per unit area on the containing walls by a
fluid.
Gauge pressure is the difference between
absolute pressure & atmospheric pressure.
Differential pressure is the difference between
two pressure.
Pg =Pa- PsPd= P1-P2
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CLASSIFICATION OF PRESSURE
SENSING DEVICESCLASSIFICATION
OF PRESSURESESING DEVCE
Depending on
principle of
working
Depending on
Pressure range
Mechanical ElectroMechanical Electronic High Pressureup to 70000 Mpa Low In Micro
Manometer
Elastic Element
Potentiometeric
Transducer
Strain Gauge
Photo Electric
Transducer
Piezoelectric
Transducer
Mcleod gauge
Knudsen Gauge
Praini Gauge
Mechanical
Electro
Mechanical
MECHANICAL INSTRUMENT
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MECHANICAL INSTRUMENT:-
Pressure measurement is made bybalancing the unknown force produced by
pressure under measurement like manometer,elastic element.
ELECTROMECHANICALINSTRUMENT:-
Employ mechanical means for detectingpressure & electrical means for indicating likestrain gauge.
ELECTRONIC INSTRUMENT:-Physical changes caused by pressure
are detected & indicated by electronic meanslike gauges used for vacuum measurement.
MANOMETERS
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MANOMETERS
The principle of working is that the unknownpressure is balanced against gravitational forceof liquid heads.
Manometer bodies are made up of brass, steel,aluminum & tubes are made up of Pyrex.
Its range is low vacuum to 0.1 MN/m2.
Its types are:-
U-tube
Well type
Inclined type
Ring type
Micro manometer
WHICH ONE IS THE BEST MANOMETERIC FLUID
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WHICH ONE IS THE BEST MANOMETERIC FLUID
WATER OR MERCURY?
Cheap & convient is water but it has following
drawback..It evaporates and therefore, the gauge needs frequent
topping off.
It is also transparent so it makes readability difficult, adie has to be used to make it coloured.
But mercury is best suited for this.
Other manometeric fluids are:
Transformer oil
Aniline
Carbon teterachloride
Bromophome
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U-TUBE MANOMETER
It is used for measurement of liquid & gas
pressure. The manometer is filled with a manometeric
fluid whose specific gravity is known.
The difference between the pressures on twolimbs of the Manometer is a function of h.
So the pressure is
P=P1+ghf= P2 + ghmP = P1-P2 = gh(m- f)
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They are available with the ranges up to 40kN/m2
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They are available with the ranges up to 40kN/m2.
Its maximum operating pressure is up to 3MN/m2.
Its dynamic response is poor.
But in this there is a small change in pressure, so one
leg of this is converted into well shape & named as
Well type manometer.
But in Well type again there is small change in the legof Well type manometer.
So then the vertical leg is placed at some inclination
angle which is named as Inclined tube manometer & if
there is small change in pressure in the well causeslarge change in the measurement level of liquid in the
inclined leg. It is shown in the figure.
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They have much higher sensitivity then
that of vertical limited. They are available in ranges from 0-10mm
of water to 0-100mm of water using water
as manometeric fluid & up to 0-1250mm of
mercury using mercury as manometeric
fluid.
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ELASTIC PRESSURE ELEMENTIts principle of working can be explained through flow chart.
Displacement caused by pressure
Displacement actuates Pointer on scale
If
Signal isdirect
Measure
Secondary Transducer converts signal into electrical
form
Show the value ofPressure
Electrical signal is shown as O/P
No
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TYPES OF ELASTIC ELEMENT
TYPES OF
ELASTIC
ELEMENTS
BOURDON
TUBEBELLOWS DIAPHRAGM
C - SHAPE SPIRAL HELICAL
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BOURDON TUBE
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In C-type, geared sector & pinion arrangement is
used for magnification of the output & pointing
on the scale. But it led to backlash error & itsaccuracy is poor which is + 1%.
So to improve this spiral or helical type is used.
In spiral type displacement is increased byincreasing the number of coils & there is no
need of further magnification.
In helical displacement is larger than spiral type.
Bourdon tubes are made up of brass, stainless
steel, bronze, monel, phosphorous bronze, alloy
steel.
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BELLOWS
Metallic bellows are having series of circular
parts joined in such a manner that they are
contracted or expanded axially by change in
pressure. Material used should be flexible, ductile.
For construction of bellows brass, bronze,
beryllium etc can be used.
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Bellows can be used for measurement of
differential, absolute, gauge pressure . It is
shown in fig.
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LOW PRESSURE SENSING
DEVICES
It is used for measurement of low
pressure.
For these measurements gauges are
used.
They are:-
McLeod gauge
Knudsen gauge
Pirani gauge
Ionization gauge
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MCLEOD GAUGE
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STRAIN GAUGE
Its principle of working is piezoresistive
effect.
In this if a metal conductor is stretched or
compressed its resistance changes on
account of the fact that both length &
diameter of conductor changes which also
led to change in resistivity of conductor.
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SEMICONDUCTOR STRAIN GAUGE:-
These gauges depend for their action upon piezoresistive
effect i.e. the change in value of resistance due tochange in resistivity.
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Material used for these gauges are silicon,
germinum.
It is used for very small strains of the order of0.01 microstrain.
Piezoresistive pressure transducer which have
semiconductor strain gauge are available in
pressure ranges from 15kPa to 350MPa.
For these types of gauges pressure is applied
directly to a silicon diaphragm.
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HOW STRAIN GAUGE IS USED TO MEASURE
PRESSURE ?
Strain gauge can be used to produce anelectrical signal in proportion to the change in
resistance caused by distortion of an elastic
element.
Strain gauges are used in G.H.T.P. for pressure
measurement.
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In this plant measurement of pressure is
done by taking impulse line.
Accuracy is < + 0.25% of calibrated span. Maximum pressure range is 175.4kg/cm2
(approx.) which is BFP common discharge.
Pressure in boiler drum is 150kg/cm2. Minimum pressure is 0.884kg/cm2 which
is in condenser.
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