Table of contents

 

Section 1. The steam turbine

1. Turbine types

   1.1. Direction of flow
   1.2. Cylinder and exhaust arrangements
   1.3. Speed of rotation


2. Efficiency and output

   2.1. Output limitations
      2.1.1. Steam valve pressure drop
      2.1.2. Swallowing capacity
   2.2. Moving blades
      2.2.1. Impulse-type turbine
      2.2.2. Reaction-type turbine
      2.2.3. Effect on turbine design
      2.2.4. Blade efficiency
      2.2.5. Modern blading designs
      2.2.6. LP turbine blading
   2.3. The effect of clearances on real designs
      2.3.1. Profile loss
      2.3.2. Secondary loss
      2.3.3. Tip leakage
      2.3.4. Disc windage
      2.3.5. Lacing wires
      2.3.6. Other losses
      2.3.7. Wetness loss
      2.3.8. Annulus loss
   2.4. Stage efficiency and the condition line
      2.4.1. Efficiency of stage
      2.4.2. The condition line
      2.4.3. Cylinder efficiency
      2.4.4. Leaving loss
      2.4.5. Hood loss
      2.4.6. Wetness loss
      2.4.7. Partial admission


3. Thermodynamics of the steam cycle

   3.1. Development of the modern steam cycle
      3.1.1. The steam cycle
      3.1.2. The Rankine cycle
      3.1.3. Practical cycle using superheat
      3.1.4. The reheat cycle
      3.1.5. Regenerative feedheating
   3.2. Cycle efficiency and heat rate
      3.2.1. Cylinder efficiency
      3.2.2. Heat rate
   3.3. Terminal conditions
      3.3.1. Effect of steam inlet conditions
      3.3.2. Effect of reheat conditions
      3.3.3. Effect of pressure loss in pipework and valves
      3.3.4. Effect of final feed temperatures
      3.3.5. Effect of exhaust pressure
   3.4. Superheat cycle
      3.4.1. Steam conditions
      3.4.2. Reheat
      3.4.3. Double reheat
      3.4.4. CEGB cycles
      3.4.5. Turbine designs
   3.5. Wet steam cycle
      3.5.1. The PWR steam cycle
      3.5.2. Cycle considerations
      3.5.3. Full-speed or half-speed machines


4. Economics of the steam cycle

   4.1. Choice of exhaust pressure
      4.1.1. Thermodynamic optimisation
      4.1.2. General economic optimisation of plant
      4.1.3. Economic optimisation of exhaust pressure, condenser and CW system
   4.2. Regenerative feedheating
      4.2.1. Feedheating plant stages — superheat cycles
      4.2.2. Feedheating plant stages — wet steam cycle
      4.2.3. Feedwater de-aeration
      4.2.4. Low pressure feedwater heaters
      4.2.5. High pressure feedwater heaters
      4.2.6. Summary
   4.3. Choice of feed pump and drive system
      4.3.1. Feed pump size and number
      4.3.2. Feed pump duty, margins, and the need for variable speed
      4.3.3. Economic comparison of steam turbine drives with electric motor drives
      4.3.4. Economic comparison of variable-speed motor (VSM) drive with induction motor plus fluid-coupling drive
      4.3.5. Example of the results of an overall comparison of the through-life costs of four feed pump system options
   4.4. Turbine by-pass systems
      4.4.1. Superheat plant
      4.4.2. By-pass capacity
      4.4.3. System effects
      4.4.4. Improvement of start-up capability
      4.4.5. PWR wet steam plant


5. Turbine blading

   5.1. Impulse stages
      5.1.1. Moving blades — details and construction
      5.1.2. Fixed blades — details and construction
      5.1.3. Velocity-compounded stage
   5.2. Reaction stages
      5.2.1 Fixed and moving blades — details and construction
   5.3. Low pressure stages
      5.3.1. Aerodynamic and mechanical constraints
      5.3.2. Blade tip restraint
      5.3.3. Baumann exhaust
   5.4. Moving blade root attachments
      5.4.1. Fir-tree roots
      5.4.2. Pinned roots
   5.5. Diaphragm construction and support
      5.5.1. Kinematic support
      5.5.2. Radial support pads
      5.5.3. Diaphragm construction
   5.6. Blading materials
      5.6.1. 12% Cr steels
      5.6.2. Titanium
   5.7. Blade vibration control
      5.7.1. Natural frequencies and excitation frequencies
      5.7.2. Sources of vibration excitation
      5.7.3. Verification of estimated natural frequencies and wheel chamber tests
      5.7.4. Methods of vibration control
   5.8. Erosion protection
      5.8.1. Erosion mechanism
      5.8.2. Erosion progression
      5.8.3. Protection and erosion shield materials


6. Turbine casings

   6.1. Forms of casing construction
      6.1.1. High pressure casings
      6.1.2. Intermediate pressure casings
      6.1.3. Low pressure casings
   6.2. Horizontal joints
      6.2.1. Flange design
      6.2.2. Bolting
   6.3. External connections
      6.3.1. Steam inlets — HP and IP
      6.3.2. HP exhausts
      6.3.3. IP exhausts
      6.3.4. Use of thermal skirts and piston rings
      6.3.5. LP cylinders
      6.3.6. Bled-steam connections
   6.4. Casing materials
   6.5. Support and alignment
      6.5.1. HP and IP cylinder supports
      6.5.2. LP cylinder supports
   6.6. Casing and diaphragm glands
   6.7. Lagging


7. Turbine rotors and couplings

   7.1. Types of rotor construction
      7.1.1. Design for high temperature operation
      7.1.2. Cooling of IP rotors
   7.2. Rotor materials
      7.2.1. HP and IP rotors
      7.2.2. LP rotors
   7.3. Rotor testing and balancing
      7.3.1. Thermal stability
      7.3.2. Overspeed testing
      7.3.3. Rotor balancing
      7.3.4. Critical speeds
      7.3.5. Rotor fast fracture risk assessment
   7.4. Couplings
      7.4.1. Flexible couplings
      7.4.2. Semiflexible couplings
      7.4.3. Rigid couplings
   7.5. Rotor alignment
      7.5.1. Alignment technique
      7.5.2. On-line monitoring


8. Bearings, pedestals and turning gear

   8.1. Journal bearings
      8.1.1. Construction
      8.1.2. Instrumentation
      8.1.3. Bearing performance
      8.1.4. Factors affecting bearing life
   8.2. Thrust bearings
   8.3. Pedestals
   8.4. Oil sealing arrangements
   8.5. Turning gear
      8.5.1. Hand barring arrangement
      8.5.2. Electrical turning gear (ETC)


9. Turbine applications

   9.1. Power generation
   9.2. Mechanical drive
   9.3. Combined heat and power (CHP)
   9.4. Combined-cycle plant


10. Future outlook

   10.1. Unit size and rating
   10.2. Supercritical plant
   10.3. Turbine blading development


11. References

 

Section 2. Turbine plant systems

1  Governing systems

  1.1  Introduction
  1.2  Governor characteristics
    1.2.1  Simple scheme — boiler on pressure control
    1.2.2  Turbine master load controller with boiler on pressure control
    1.2.3  Boiler master load controller
  1.3  Subsidiary functions
    1.3.1  Acceleration feedback
    1.3.2  Unloading gear
    1.3.3  Governor speed reference
    1.3.4  Closed-loop control of turbine electrical load
    1.3.5  Overspeed testing
    1.3.6  On-load testing
    1.3.7  Automatic run-up and loading systems
  1.4  Electronic governing part 1 ...2 ...3 ...4 ...5 ...6 ...7 ...8
    1.4.1  Digital processing
  1.5  Governor valve relays part 1 ...2 ...3 ...4
    1.5.1  Governor valve relay and control unit Type 1
    1.5.2  Governor valve relay and control unit Type 2
    1.5.3  Governor valve relay and control unit Type 3
    1.5.4  Reheater relief valves
  1.6  Hydraulic fluid system part 1 ...2 ...3
    1.6.1  Filtration
  1.7  Boiler feed pump turbine governors

 

2  Steam chests, valves and loop pipes

  2.1  Steam chest arrangements and construction
  2.2  Steam chest materials
  2.3  Cover seals
  2.4  Steam strainers
  2.5  Stop valves
  2.6  Governor valves
  2.7  Loop pipework
  2.8  Crossover pipework

 

3  Turbine protective devices

  3.1  Possible hazards
  3.2  Protection scheme
  3.3  Electrically-signalled trips
  3.4  Overspeed trip
  3.5  Mechanically-operated trips
  3.6  Operator tripping facilities

 

4  Turbine instrumentation

  4.1  Classification of instrumentation
    4.1.1  Supervisory instrumentation
    4.1.2  Efficiency instrumentation
    4.1.3  Auxiliary system instrumentation
    4.1.4  Condition monitoring instrumentation
    4.1.5  Instrumentation associated with protection and control equipment
    4.1.6  Instrumentation to provide post-incident records

 

5  Turbine foundations

  5.1  Tuning
  5.2  Concrete foundations
  5.3  Steel foundations
  5.4  Spring foundations
  5.5  Sub-foundation

 

6  Lubrication systems

  6.1  Lubrication requirements and typical arrangements
  6.2  Oil pumps
    6.2.1  Main lubricating oil pump
    6.2.2  Turbine-driven oil booster pump
    6.2.3  AC and DC motor-driven auxiliary oil pumps
    6.2.4  Jacking-oil pumps and priming pumps
    6.2.5  Other pumps
  6.3  Oil tanks
  6.4  Piping
  6.5  Oil coolers
  6.6  Oil strainers and filters
  6.7  Oil purifiers and coalescers
    6.7.1  Centrifugal separation systems
    6.7.2  Static oil purifiers/coalescers
  6.8  Oils and greases
    6.8.1  Oils
    6.8.2  Greases
  6.9  Jacking oil systems
  6.10  Greasing systems

 

7  Gland sealing system

  7.1  Function and system layout
    7.1.1  Labyrinth glands
    7.1.2  System layout
  7.2  Temperature and pressure control
    7.2.1  Temperature control
    7.2.2  Pressure control
  7.3  Gland steam condenser

 

8  Flange heating system

  8.1  Function and system layout
  8.2  Control

 

9  LP exhaust spray cooling system

  9.1  Function and system layout
  9.2  Control

 

10  Drains systems

  10.1  Function and system layout
    10.1.1  Start-up drains
    10.1.2  Continuous drains

  10.2  Control

 

11  By-pass systems

  11.1  Configuration
    11.1.1  Pressure control valves
    11.1.2  Isolating valves
    11.1.3  Dump tube
  11.2  By-pass systems for nuclear plant
  11.3  By-pass systems for fossil-fired plant
  11.4  Problems with by-pass systems
    11.4.1  Noise
    11.4.2  Water ingress
    11.4.3  Thermal shock
    11.4.4  Leakage flows

 

12  Operational flexibility

  12.1  Typical operational regimes
    12.1.1  Base load
    12.1.2  Two-shifting
    12.1.3  Load cycling
  12.2  Influence on machine design
    12.2.1  Turbine cylinders
    12.2.2  Turbine rotors
    12.2.3  Stress monitors
  12.3  Forced-air cooling
    12.3.1  Cooling of turbine
    12.3.2  Cooling system

 

13  Wet steam turbine plant

  13.1  Influence of steam on components part 1 ...2 ...3
  13.2  Water extraction devices
  13.3  Erosion protection
  13.4  Moisture separator reheaters (MSRs)
    13.4.1  Separators part 1 ...2 ...3 ...4
    13.4.2  Steam-to-steam reheaters part 1 ...2 ...3 ...4 ...5 ...6 ...7
  13.5  Steam supply and drains systems
    13.5.1  First-stage reheat
    13.5.2  Second-stage reheat
    13.5.3  Performance monitoring
    13.5.4  System drains
    13.5.5  Separator drains
    13.5.6  Reheater drains

 

14  References

 

Section 3. Feedwater heating systems

1  Feed system design

   1.1  Introduction
   1.2  Functional needs of the system
   1.3  System configuration
   1.4  Component design parameters
   1.5  Component levels
   1.6  Maintenance of system water content
   1.7  Protection against use of contaminated feedwater
   1.8  Protection against ingress of water/steam to turbines
   1.9  Summary

 

2  HP feed system

   2.1  Introduction
   2.2  System parameters
   2.3  System configuration part 1 ...2 ...3
   2.4  HP heater drains system
   2.5  Pipework arrangement

 

3  De-aerator system

   3.1  Introduction
   3.2  De-aerator heater
   3.3  De-aerator storage tank
   3.4  De-aerator elevation
   3.5  Protection systems
   3.6  Protection valves
   3.7  Pipework
   3.8  Boiler feed pump suction filters

 

4  Low pressure feed system

   4.1  Introduction
   4.2  Low pressure system configuration part 1 ...2 ...3 ...4
   4.3  Pipework and valves

 

5  Designs of feedheaters

 

6  High pressure feedwater heaters

   6.1  Functional needs
   6.2  Construction of high pressure heaters
   6.3  Water header, tube bundle and shell
      6.3.1  To find tube thickness
      6.3.2  Area required for flow through the tube bundle
      6.3.3  Tubeplate thickness
      6.3.4  Water header wall thickness
      6.3.5  Header branch thickness
      6.3.6  Compensation for openings in the water header
      6.3.7  Shell and dished end thickness
   6.4  Heater tube length and tube supports
      6.4.1  Length of U-tubes
      6.4.2  Tube support plates
   6.5  Bled-steam inlet
   6.6  Thermal design
      6.6.1  Desuperheating section
      6.6.2  Condensing section
      6.6.3  Drain cooling section
      6.6.4  Other factors affecting thermal design
   6.7  Horizontal high pressure heaters
   6.8  Vertical high pressure heaters
   6.9  Alternative designs of heater construction

 

7  De-aerating feedheaters

   7.1  Introduction
   7.2  Thermal/hydraulic design part 1 ...2
   7.3  De-aerator construction

 

8  Low pressure heaters

   8.1  Introduction
   8.2  Surface type low pressure heaters
   8.3  Construction of low pressure heaters
   8.4  Water header, tube bundle and shell
      8.4.1  Tube thickness
      8.4.2  Flow area
      8.4.3  Tubeplate thickness
      8.4.4  Water header wall thickness
      8.4.5  Water header branch thickness
      8.4.6  Compensations for openings in the waterbox
      8.4.7  Shell and dished end thickness
   8.5  Heater tube length and tube supports
      8.5.1  Tube support plates
   8.6  Bled-steam inlets and drain outlets
   8.7  Thermal design
   8.8  External drain coolers
      8.8.1  Thermal/hydraulic design of a flashing drain cooler
      8.8.2  Thermal/hydraulic design of a water-to-water drain cooler
   8.9  Direct contact low pressure heaters

 

9  Evaporators and other means of water treatment

   9.1  Introduction
   9.2  Types of bled-steam evaporator
   9.3  Surface type evaporator
   9.4  Flash type evaporators

 

10  Future developments

   10.1  HP feed system
   10.2  De-aerator system
   10.3  LP feed system

 

11  References

 

Section 4. Condensers, pumps and cooling water

CONDENSERS

1  Introduction

2  Economics

   2.1  Condenser surface area, turbine exhaust pressure and CW flow
      2.1.1  Input data
      2.1.2  Computation

 

3  Historical development and layout

   3.1  Phase 1
   3.2  Phase 2
   3.3  Phase 3

 

4  Environmental considerations

   4.1  Cooling water quality
      4.1.1  Corrosion prevention part 1 ...2
      4.1.2  Other copper-alloy tube failure mechanisms part 1 ...2
      4.1.3  Material selection part 1 ...2

 

5  Thermal design

   5.1  Theory
      5.1.1  Heat rejected
      5.1.2  Heat transfer
   5.2  Design codes, standards and specifications
      5.2.1  HEI Standards
      5.2.2  BEAMA design recommendations
      5.2.3  CEGB specifications
   5.3  Influence of tubeplate and tubenest geometry on thermal performance
      5.3.1  Subjective design evaluation part 1 ...2 ...3 ...4 ...5
      5.3.2  Computer assisted design evaluation

 

6  Mechanical design

   6.1  Introduction
   6.2  Constructional development
      6.2.1  Construction materials
      6.2.2  Design forces and stresses
      6.2.3  Methods of manufacture and construction part 1 ...2 ...3 ...4 ...5 ...6 ...7
   6.3  Protection and cleanliness of condensers
      6.3.1  Debris filter
      6.3.2  Condenser tube cleaning system
   6.4  Special considerations

 

7  Operational life limiting constraints

7.1  Condenser air inleakage
      7.1.1  Locating air leaks
      7.1.2  Measurement of air leakage rate
   7.2  Cooling water leakage in condensers
      7.2.1  Fluorescein method
      7.2.2  Foam or film methods
      7.2.3  Bubbler devices
      7.2.4  Tracer gas methods
      7.2.5  Flame and smoke methods
      7.2.6  Ultrasonic method
   7.3  Condenser fouling and cleaning
      7.3.1  Condenser fouling
      7.3.2  On-load condenser cleaning
      7.3.3  Off-load condenser cleaning

 

8  Plant testing

   8.1  Introduction
      8.1.1  Test codes and practices part 1 ...2 ...3

 

9  Future developments

   9.1  Aims and objectives
   9.2  Research and development
      9.2.1  Tubenest layout
      9.2.2  Thermal performance properties of tubing

PUMPS

10  Air extraction equipment

   10.1  Introduction
   10.2  Determination of air extraction quantity
      10.2.1  The mechanism of air extraction
      10.2.2  The condenser air cooling section
   10.3  Review of air extraction equipment
      10.3.1  Hydraulic air pumps
      10.3.2  Liquid-ring type air pump
      10.3.3  Air ejector/pump systems
      10.3.4  Steam ejector/pump systems
   10.4  Quick-start plant requirements
      10.4.1  Type of plant
      10.4.2  Starting times

 

11  Hydraulic aspects of centrifugal pumps

   11.1  Specific speed
   11.2  Net positive suction head
   11.3  Suction specific speed

 

12  Circulating water pumps

   12.1  Introduction
   12.2  Horizontal split-casing pumps
   12.3  Vertical pumps
      12.3.1  Vertical metal-casing pumps
      12.3.2  Concrete volute pumps
   12.4  Gearboxes
   12.5  Shaft seals
   12.6  Pump testing
   12.7  Materials

 

13  Condenser extraction pumps part 1 ...2

 

14  Boiler feed pumps

   14.1  Introduction
   14.2  Feed pump developments
   14.3  Advanced class feed pump construction
   14.4  Axial thrust
   14.5  Gland sealing part 1 ...2
   14.6  Pump layout and drive part 1 ...2
   14.7  Light load protection
   14.8  Testing
   14.9  PWR feed pumpsets
   14.10  Future trends

 

15  Miscellaneous pumps

   15.1  Service water pumps
   15.2  Chemical injection pumps
   15.3  Fire pumps

 

16  References