PowerPoint Presentation On Turbine Rolling And Synchronization

PPT On Turbine Rolling And Synchronization
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Turbine Rolling And Synchronization Presentation Transcript:

1. OBJECTIVE
THE OBJECTIVE OF STARTING UP OF THE TURBOGENERATOR IS TO BRING A UNIT ON LOAD AND RAISE IT TO THE RATED OUTPUT WITHIN THE OPTIMUM TIME BUT WITHOUT UNDUE STRESSES ON THE TURBINE COMPONENTS.

2. TYPES OF START UP
Turbine Start up are classified as Cold, Hot & Warm Start up

3. General Preparation of Start up
All the repair works on the turbine are completed and all PTWs are cancelled.
All the Turbo-supervisory instruments are available.
Generator excitation system,GT & UAT cooling system,seal oil system etc.are OK
All the interlocks and protections of Turbine & Generator are already checked up and kept I/s.

4. Unit status before Turbine Rolling
Turbo-Generator on Burring gear with all Turbo supervisory parameters are normal.
Boiler is lighted up condition with one or two oil elevations are I/s.
HP-LP Bypass is in charged condition.
Boiler load index is 95 to 100 T/Hr.
Steam parameter are ready for rolling. M.S. Pr. 35-40 Ksc. HRH Pr. 12-14 Ksc. M.S. and HRH Tempr. – 320 to 3500C

5. Start up Considerations
During the startup the Turbine is subjected to “Non-Steady state operation”.
This covers the operating condn where Speed, steam Pressure and temperature change with time.
Under these condn turbine components which are exposed to temperature changes subjected to thermal stress and expansion.
For turbine life point of view, it is very much necessary to limit the extent of these temperature changes.

6. To take care of the above factor the operator has to follow the recommendations from Turbine Stress Evaluator and start the Rolling procedure by following Criteria curves X1 to X7 right from the beginning. TURBINE STRESS EVALUATOR
The Turbine is equipped with the TSE which provides adequate guidance to the operator by indicating tempr margins and Load margins.
These Margins have been derived on the basis of Actual Thermal Stress and Material Fatigue.

7. Frequent and substantial departures from criteria curves and TSE Indication can result
a.Reduction in total life of Turbine
b.Non permissible deformation. and
c.Cracking of Turbine Components.

8. RESETTING THE TURBINE
Why Turbine Resetting?
When the Turbine trips due to Electrical or Mechanical Protection Trip oil drains quickly. In the absence of the Trip oil Turbine Stop and Control vlvs closes quickly.
So the Trip oil is basically required for keeping the ESVs and IVs in open condn and getting required Secondary oil pressr for opening the HPCVs and IPCVs. .

9. The Trip oil again can be generated again by Resetting the Turbine.
Now to Reset the Turbine We have to
 Reset the Unit Or Master Trip Relay.
Bring the Starting Device to Zero.

10. For more please refer our PPT. Thank You.

PowerPoint Presentation On STEAM TURBINE

PPT On STEAM TURBINE
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STEAM TURBINE Presentation Transcript

1. Presentation Outline
Theory of Turbine
Turbine casing
Rotor & Blades
Sealing system & barring gear
ESV’s, IV’s and CV’s
Coupling and Bearing

2. Steam Turbine
A steam turbine is a mechanical device that extracts thermal energy from pressurized steam, and converts it into useful mechanical work.

3. Impulse Turbines
An impulse turbine uses the impact force of the steam jet on the blades to turn the shaft. Steam expands as it passes through the nozzles, where its pressure drops and its velocity increases. As the steam flows through the moving blades, its pressure remains the same, but its velocity decreases. The steam does not expand as it flows through the moving blades.

4. Reaction Turbines
In the reaction turbine, the rotor blades themselves are arranged to form convergent nozzles. This type of turbine makes use of the reaction force produced as the steam accelerates through the nozzles formed by the rotor.

5. TURBINE COMPONENTS
CASING
ROTOR
BLADES
SEALING SYSTEM
STOP & CONTROL VALVES
COUPLINGS & BEARINGS
BARRING GEAR

 6. Turbine Casings
HP Turbine Casing
outer casing: a barrel-type without axial or radial flange.
Barrel-type casing suitable for quick startup and loading.
The inner casing--- cylindrical , axially split.
The inner casing is attached in the horizontal and vertical planes in the barrel casing so that it can freely expand radially in all directions and axially from a fixed point (HP-inlet side).

7. IP Turbine Casing
The casing of the IP turbine is split horizontally and is of double-shell construction.
Both are axially split and A double flow inner casing is supported in the outer casing and carries the guide blades.
Provides opposed double flow in the two blade sections and compensates axial thrust.
Steam after reheating enters the inner casing from Top & Bottom.

8. LP Turbine Casing
The LP turbine casing consists of a double flow unit and has a triple shell welded casing.
The shells are axially split and of rigid welded construction.
The inner shell taking the first rows of guide blades, is attached kinematically in the middle shell.
Independent of the outer shell, the middle shell, is supported at four points on longitudinal beams.
Steam admitted to the LP turbine from the IP turbine flows into the inner casing from both sides.

9. Anchor Point of Turbine
 Purpose: Taking care of thermal expansions and contractions of the machine during thermal cycling.
The fixed points of the turbine are as follows:
The bearing housing between the IP and LP turbines.
The rear bearing housing of the IP turbine.
The longitudinal beam of the I.P turbine.
The thrust bearing in rear bearing casing of H.P turbine.

10. For more please refer our PPT. Thank You.

PowerPoint Presentation On Turbine Vacuum System

PPT On Turbine Vacuum System
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Turbine Vacuum System Presentation Transcript:

1. Presentation outline
Why Vacuum system is required ?
Parts of Vacuum system?
Steam Ejectors
Vacuum Pumps

2. Why is it required?
The steam turbine is a device to convert the heat in steam to mechanical power.
Enthalpy drop across the turbine decides the work output of the turbine. For increasing this enthalpy drop across the turbine we need effective condenser vacuum system.
By condensing the exhaust steam of turbine, the exhaust pressure is brought down below atmospheric pressure, increasing the steam pressure drop between inlet and exhaust of steam turbine. This further reduction in exhaust pressure gives out more heat per unit weight of steam input to the steam turbine, for conversion to mechanical power.

3. Parts of Vacuum System
Condenser
CW system
Ejectors/Vacuum pumps
Gland Sealing System

4. CONDENSER
The functions of condenser are:
To provide lowest economic heat rejection temperature for the steam. Thus saving on steam required per unit of electricity.
To convert exhaust steam to water for reuse for thus saving on feed water requirement.
De-aeration of make-up-pump water introduced in the condenser.
To form a convenient point for introducing make up water.

5. Steam Condenser
Steam condenser is a closed space into which steam exits the turbine and is forced to give up its latent heat of vaporization.
It is a necessary component of a steam power plant because of two reasons.
It converts dead steam into live feed water.
It lowers the cost of supply of cleaning and treating of working fluid.
It is far easier to pump a liquid than a steam.
It increases the efficiency of the cycle by allowing the plant to operate on largest possible temperature difference between source and sink.
The steam’s latent heat of condensation is passed to the water flowing through the tubes of condenser.
After steam condenses, the saturated water continues to transfer heat to cooling water as it falls to the bottom of the condenser called, hotwell.
This is called subcooling and certain amount is desirable.
The difference between saturation temperature corresponding to condenser vaccum and temperature of condensate in hotwell is called condensate depression.

6. Thermal Processes Occurring in Condensers
The condenser never receives pure seam from the turbine.
A mixture of steam and non-condensable gases (Air-steam mixture) enters the condenser.
The ratio of the quantity of gas that enters the condenser to the quantity of steam is called the relative air content.

7. Condenser
Steam from last stage of LPT Exhausts on condenser tube
condensation of steam takes place
Water collected in hot well

8. Surface Condenser ( shell and tube)
A surface condenser is basically a shell and tube heat exchanger with phase change. The main parts of a condenser are as follows.
1-SHELL
2-TUBES
3-TUBE SHEETS

9. For more please refer our PPT. Thank You.