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Condenser Performance Presentation Transcript
1.Condenser Performance
2.POSSIBLE CAUSES OF DEVIATION IN CONDENSER
1. Air Ingress
Excess Condenser Heat Load
Tube Fouling
4. Low Circulating Water Flow
5. Increase in circulating water inlet temperature
caused by:
i) Changes in ambient conditions
ii) Problems with cooling tower performance
1. Air Ingress
Excess Condenser Heat Load
Tube Fouling
4. Low Circulating Water Flow
5. Increase in circulating water inlet temperature
caused by:
i) Changes in ambient conditions
ii) Problems with cooling tower performance
3. PRESENT TECHNIQUE
HP JET
SPONGE RUBBER BALLS (ON LINE)
BACK WASHING (USE OF FOUR WAY VALVE)
CHEMICAL CLEANING(IN WORST CASE)
4. NEW TECHNIQUE
CONDENSER TUBE CLEANING BY WATER POWERED
CLEANERS.
FEATURES OF CLEANERS
CLEANERS USED ARE HAVING BLADES PROVIDING
OVERLAPPING COVERAGE.
CLEANERS ARE FLEXIBLE AND SUITABLE FOR ALL
TYPE OF TUBE MATERIALS.
CLEANER BLADES PRECISELY MATCH WITH
TUBE INSIDE DIA
EFFECTIVE ALL THROUGH THE LENGTH OF TUBE
HP JET
SPONGE RUBBER BALLS (ON LINE)
BACK WASHING (USE OF FOUR WAY VALVE)
CHEMICAL CLEANING(IN WORST CASE)
4. NEW TECHNIQUE
CONDENSER TUBE CLEANING BY WATER POWERED
CLEANERS.
FEATURES OF CLEANERS
CLEANERS USED ARE HAVING BLADES PROVIDING
OVERLAPPING COVERAGE.
CLEANERS ARE FLEXIBLE AND SUITABLE FOR ALL
TYPE OF TUBE MATERIALS.
CLEANER BLADES PRECISELY MATCH WITH
TUBE INSIDE DIA
EFFECTIVE ALL THROUGH THE LENGTH OF TUBE
5.Condenser Tube Cleaning Techniques
PROCESS.
SPRING LOADED CLEANERS PROPELLED
AT HIGH SPEED (3-6 M/SEC).
CLEANERS SHOT BY MEDIUM WATER PRESSURE
(20-25 KG/CM2)
CLEANERS HAVE HIGH BODY STRENGTH TO FLUSH
OUT HARD DEPOSITS.
REMOVE DEBRIS SUCH AS RUBBER PLUGS ,
RUBBER BALLS , PLASTIC ETC.
EACH CLEANER CAN BE USED 10-12 TIMES.
6.TYPE OF CLEANERS / BRUSHES
FOR SOFT DEPOSITS
FOR HARD DEPOSITS
BENEFITS OF NEW TECHNIQUE.
LEAVES BEHIND POLISHED SHINING
SURFACE ALL THROUGH THE TUBE LENGTH.
DRASTICALLY REDUCES ACCUMULATION OF
FUTURE DEPOSIT.
VERY FAST PROCESS, 3-4 DAYS FOR A 210MW
CONDENSER CLEANING.
VERY SAFE, OPERATING PRESSURE, 15-25 KG/CM2
ONLY
PROCESS.
SPRING LOADED CLEANERS PROPELLED
AT HIGH SPEED (3-6 M/SEC).
CLEANERS SHOT BY MEDIUM WATER PRESSURE
(20-25 KG/CM2)
CLEANERS HAVE HIGH BODY STRENGTH TO FLUSH
OUT HARD DEPOSITS.
REMOVE DEBRIS SUCH AS RUBBER PLUGS ,
RUBBER BALLS , PLASTIC ETC.
EACH CLEANER CAN BE USED 10-12 TIMES.
6.TYPE OF CLEANERS / BRUSHES
FOR SOFT DEPOSITS
FOR HARD DEPOSITS
BENEFITS OF NEW TECHNIQUE.
LEAVES BEHIND POLISHED SHINING
SURFACE ALL THROUGH THE TUBE LENGTH.
DRASTICALLY REDUCES ACCUMULATION OF
FUTURE DEPOSIT.
VERY FAST PROCESS, 3-4 DAYS FOR A 210MW
CONDENSER CLEANING.
VERY SAFE, OPERATING PRESSURE, 15-25 KG/CM2
ONLY
7.Condenser Tube Cleaning Techniques
8.Benefits
Improvement of about 34 mmHg in Cond vacuum
In terms of HR this amounts to about 68 kcal/kwh
In terms coal saving about 5.5 crores per year
Improvement of about 34 mmHg in Cond vacuum
In terms of HR this amounts to about 68 kcal/kwh
In terms coal saving about 5.5 crores per year
9.Condenser air-in-leak test
AIR-IN LEAKAGE ADVERSELY AFFECTS CONDENSER VACUUM, HEAT RATE,
CORROSION RATE OF SYSTEM
AIR BLANKETING ON THE TUBES SEVERELY AFFECTS THE HEAT TRANFER.
1 MM LAYER OF AIR EQUALS 16 METRE THICK OF COPPER.
AIR-IN LEAKAGE ADVERSELY AFFECTS CONDENSER VACUUM, HEAT RATE,
CORROSION RATE OF SYSTEM
AIR BLANKETING ON THE TUBES SEVERELY AFFECTS THE HEAT TRANFER.
1 MM LAYER OF AIR EQUALS 16 METRE THICK OF COPPER.
10. MAJOR AREAS OF AIR INGRESS.
LP TURBINE GLANDS.
LP TURBINE DIAPHRAGMS.
LP TURBINE PARTING PLANE.
CEP GLANDS (STANDBY PUMP)
HOTWELL
TDBFP (AS APPLICABLE)
VALVE GLANDS, FLANGE JOINTS ETC
LP TURBINE GLANDS.
LP TURBINE DIAPHRAGMS.
LP TURBINE PARTING PLANE.
CEP GLANDS (STANDBY PUMP)
HOTWELL
TDBFP (AS APPLICABLE)
VALVE GLANDS, FLANGE JOINTS ETC
11. INCREASE IN SUB-COOLING OF AIR-STEAM MIXTURE.
AIR STEAM FLOW AT EJECTOR / VACUUM PUMP.
DISSOLVED OXYGEN IN CONDENSATE.
AIR STEAM FLOW AT EJECTOR / VACUUM PUMP.
DISSOLVED OXYGEN IN CONDENSATE.
12. PRESENT TECHNIQUE TO CHECK AIR-IN-LEAK LOCATIONS AND DRAWBACKS.
ULTRASONIC DETECTOR
SENSITIVITY IS LOW - 0.1 SCFM
REQUIRES HIGHER SKILLED LABOUR
IN EFFECTIVE IF BACKGROUND NOISE IS TOO HIGH.
NOT APPROACHABLE AT SOME LOCATIONS.
ULTRASONIC DETECTOR
SENSITIVITY IS LOW - 0.1 SCFM
REQUIRES HIGHER SKILLED LABOUR
IN EFFECTIVE IF BACKGROUND NOISE IS TOO HIGH.
NOT APPROACHABLE AT SOME LOCATIONS.
13. NEW TECHNIQUE
USE OF HELIUM LEAK DETECTOR .
SENSITIVITY IS VERY HIGH
- 0.00001 TO 0.000001 SCFM
BEING GAS, APPROACHABLE TO ALL LOCATIONS.
ON LINE DETECTION .
APPROX. LEVEL OF AIR-IN-LEAK CAN BE ASSESSED.
LESS TIME CONSUMING
USE OF HELIUM LEAK DETECTOR .
SENSITIVITY IS VERY HIGH
- 0.00001 TO 0.000001 SCFM
BEING GAS, APPROACHABLE TO ALL LOCATIONS.
ON LINE DETECTION .
APPROX. LEVEL OF AIR-IN-LEAK CAN BE ASSESSED.
LESS TIME CONSUMING
14. NON TOXIC GAS
DOES NOT REACT CHEMICALLY WITH OTHER
ELEMENT
DUE TO SMALL MOLECULES EASILY PASSES
THROUGH SMALLEST LEAKS
ITS CONCENTRATION IN AIR IS ONLY 5 ppm
THEREFORE LITTLE BACK GROUND
INTERFERENCE IN DETECTING LEAK
DOES NOT REACT CHEMICALLY WITH OTHER
ELEMENT
DUE TO SMALL MOLECULES EASILY PASSES
THROUGH SMALLEST LEAKS
ITS CONCENTRATION IN AIR IS ONLY 5 ppm
THEREFORE LITTLE BACK GROUND
INTERFERENCE IN DETECTING LEAK
15. SAMPLING OF AIR-STEAM MIXTURE FROM
VACUUM PUMP/STEAM EJECTOR EXHAUST.
REMOVAL OF MOISTURE FROM SAMPLE.
INSTALLATION OF DETECTOR PROBE IN A
VESSEL.
FIXING DUAL PRESSURE OXYGEN REGULATOR ON
HELIUM CYLINDER.
MOUNTING CYLINDER ON TROLLEY.
FIXING AIR GUN WITH NOZZLE TO THE
REGULATOR.
VACUUM PUMP/STEAM EJECTOR EXHAUST.
REMOVAL OF MOISTURE FROM SAMPLE.
INSTALLATION OF DETECTOR PROBE IN A
VESSEL.
FIXING DUAL PRESSURE OXYGEN REGULATOR ON
HELIUM CYLINDER.
MOUNTING CYLINDER ON TROLLEY.
FIXING AIR GUN WITH NOZZLE TO THE
REGULATOR.
16. On line Condenser air-in-leak detection using Helium leak
detector was demonstrated in one 200 MW unit
Helium Instrument setup was arranged near the Ejector
for checking the sample
Helium spray was done at different probable locations
starting from LPC diaphragms
detector was demonstrated in one 200 MW unit
Helium Instrument setup was arranged near the Ejector
for checking the sample
Helium spray was done at different probable locations
starting from LPC diaphragms
17. Condenser Air-in-Leak Test by
Helium Leak Detector
PRESENT TECHNIQUES
CONDENSER HEAT LOAD.
CW PUMP CHARACTERISTICS.
ANNUBAR
PITOT TUBE
CALIBRATION OF ELBOW TAP dp
18. Principle of dp calibration
Fluid flow around curved path (elbow), subject to
angular acceleration
Centrifugal force creates dp between inner and outer
radii
High pressure (p1) tap on outside elbow and low
pressure (p2) tap on inside elbow.
Helium Leak Detector
PRESENT TECHNIQUES
CONDENSER HEAT LOAD.
CW PUMP CHARACTERISTICS.
ANNUBAR
PITOT TUBE
CALIBRATION OF ELBOW TAP dp
18. Principle of dp calibration
Fluid flow around curved path (elbow), subject to
angular acceleration
Centrifugal force creates dp between inner and outer
radii
High pressure (p1) tap on outside elbow and low
pressure (p2) tap on inside elbow.
19. CW Flow Measurement using Elbow tap
20.Eddy Current Induction Heating for Opening / Closing of Turbine Studs/Cap nuts
New Technique
Using the principle of Eddy Current Induction heating
Principle
A mass of conducting material (Stud) is exposed to an
alternating magnetic flux.
This sets up eddy current in the Stud.
Flow of Eddy Current through the mass generates heat
New Technique
Using the principle of Eddy Current Induction heating
Principle
A mass of conducting material (Stud) is exposed to an
alternating magnetic flux.
This sets up eddy current in the Stud.
Flow of Eddy Current through the mass generates heat
21. Equipment
Induction heating unit to which 440 V, 3ph, 50 Hz supply
is given.
Output supply - 40 to 100V at 10 KHz
This high frequency supply is applied to a copper wand
which is inserted into the bore of the Stud.
Cooling is provided by continuous supply of water at
3kg/cm2 and 35 liters per minute.
Induction heating unit to which 440 V, 3ph, 50 Hz supply
is given.
Output supply - 40 to 100V at 10 KHz
This high frequency supply is applied to a copper wand
which is inserted into the bore of the Stud.
Cooling is provided by continuous supply of water at
3kg/cm2 and 35 liters per minute.
22. Operation
Copper wand of suitable length inserted into the bore of
Stud.
Heat is generated within the stud itself ensuring quick
heating of the stud
Depending upon the size of Stud rate of heating can be
adjusted by varying power supplied to the wand.
The whole operation takes 4-5 minutes.
Copper wand of suitable length inserted into the bore of
Stud.
Heat is generated within the stud itself ensuring quick
heating of the stud
Depending upon the size of Stud rate of heating can be
adjusted by varying power supplied to the wand.
The whole operation takes 4-5 minutes.
23. Benefits
Substantial reduction in time in opening / closing of Stud / Cap nuts – Reduction in unit overhauling time
No damage to the Stud / Cap nut
Rapid heating process heats up the only the Stud
without heating the shell.
Chances of any Steam Leak through horizontal joints
eliminated.
No external heat source, more safe to use.
Substantial reduction in time in opening / closing of Stud / Cap nuts – Reduction in unit overhauling time
No damage to the Stud / Cap nut
Rapid heating process heats up the only the Stud
without heating the shell.
Chances of any Steam Leak through horizontal joints
eliminated.
No external heat source, more safe to use.
24. Case Study : Station “D” (210 MW Unit)
25. Summary
Time taken in Conventional method (Gas Heater) for opening of all studs of HPT & IPT ~ 48 hrs
Time taken in Induction heating method for opening of all studs of HPT & IPT ~ 12 hrs
No seizure of studs by using Induction heating method
In the gas heating method generally 1-2 studs get stuck up/seized in the casing resulting in damage of the same
Time taken in Conventional method (Gas Heater) for opening of all studs of HPT & IPT ~ 48 hrs
Time taken in Induction heating method for opening of all studs of HPT & IPT ~ 12 hrs
No seizure of studs by using Induction heating method
In the gas heating method generally 1-2 studs get stuck up/seized in the casing resulting in damage of the same
26. Feed back from one of the SEB Stations
This technique was used in opening turbine studs/cap nuts of various sizes in one of the 210 MW units resulting in saving of 3 days in opening of Turbine casing as compared to previous method of resistance heating
No seizure of cap nuts
This technique was used in opening turbine studs/cap nuts of various sizes in one of the 210 MW units resulting in saving of 3 days in opening of Turbine casing as compared to previous method of resistance heating
No seizure of cap nuts
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