#bypasssystem — Public Fediverse posts

#BoilerManual #BypassSystem #Section7 #Page23

6. Startup can begin only when feedwater iron content is under 100 parts per billion (ppb).

7. In the startup phase, staem is sent to the deaerator for pressurization, and to the high pressure heaters for heat recovery. SSteam was also admitted to the secondary superheater and turbine. By the end of startup, all boiler components have steam flowing through them.

8. Ramping is the fourth and final stage of boiler startup. During the ramping stage, pressure, temperature and flow of the steam is brought up to 33% load. Once ramping is complete, the unit no longer needs the bypass system.

9. If iron content is low enough after cold cleanup, then hot cleanup is unnecessary. Feedwater iron content must be below 100 parts per billion (ppb) before startup is begun.

------------------------------------------------- 23 ------------------------------------------------------

#BoilerManual #BypassSystem #Section7 #Page23

6. Startup can begin only when feedwater iron content is under 100 parts per billion (ppb).

7. In the startup phase, staem is sent to the deaerator for pressurization, and to the high pressure heaters for heat recovery. SSteam was also admitted to the secondary superheater and turbine. By the end of startup, all boiler components have steam flowing through them.

8. Ramping is the fourth and final stage of boiler startup. During the ramping stage, pressure, temperature and flow of the steam is brought up to 33% load. Once ramping is complete, the unit no longer needs the bypass system.

9. If iron content is low enough after cold cleanup, then hot cleanup is unnecessary. Feedwater iron content must be below 100 parts per billion (ppb) before startup is begun.

------------------------------------------------- 23 ------------------------------------------------------

#BoilerManual #BypassSystem #Section7 #Page23

6. Startup can begin only when feedwater iron content is under 100 parts per billion (ppb).

7. In the startup phase, staem is sent to the deaerator for pressurization, and to the high pressure heaters for heat recovery. SSteam was also admitted to the secondary superheater and turbine. By the end of startup, all boiler components have steam flowing through them.

8. Ramping is the fourth and final stage of boiler startup. During the ramping stage, pressure, temperature and flow of the steam is brought up to 33% load. Once ramping is complete, the unit no longer needs the bypass system.

9. If iron content is low enough after cold cleanup, then hot cleanup is unnecessary. Feedwater iron content must be below 100 parts per billion (ppb) before startup is begun.

------------------------------------------------- 23 ------------------------------------------------------

#BoilerManual #BypassSystem #Section7 #Page23

6. Startup can begin only when feedwater iron content is under 100 parts per billion (ppb).

7. In the startup phase, staem is sent to the deaerator for pressurization, and to the high pressure heaters for heat recovery. SSteam was also admitted to the secondary superheater and turbine. By the end of startup, all boiler components have steam flowing through them.

8. Ramping is the fourth and final stage of boiler startup. During the ramping stage, pressure, temperature and flow of the steam is brought up to 33% load. Once ramping is complete, the unit no longer needs the bypass system.

9. If iron content is low enough after cold cleanup, then hot cleanup is unnecessary. Feedwater iron content must be below 100 parts per billion (ppb) before startup is begun.

------------------------------------------------- 23 ------------------------------------------------------

#BoilerManual #BypassSystem #Section7 #Page23

6. Startup can begin only when feedwater iron content is under 100 parts per billion (ppb).

7. In the startup phase, staem is sent to the deaerator for pressurization, and to the high pressure heaters for heat recovery. SSteam was also admitted to the secondary superheater and turbine. By the end of startup, all boiler components have steam flowing through them.

8. Ramping is the fourth and final stage of boiler startup. During the ramping stage, pressure, temperature and flow of the steam is brought up to 33% load. Once ramping is complete, the unit no longer needs the bypass system.

9. If iron content is low enough after cold cleanup, then hot cleanup is unnecessary. Feedwater iron content must be below 100 parts per billion (ppb) before startup is begun.

------------------------------------------------- 23 ------------------------------------------------------

#BoilerManual #BypassSystem #Section7 #Page22

Answers for bypass system

1. Before universal pressure boilers can be fired, a minimum feedwater flow must be established. This is accomplished by the use of the bypass system.

2. The four modes of boiler operation are:

.......... 1. ___Cold Cleanup_______________

.......... 2. ___Hot Cleanup________________

.......... 3. ___Startup____________________

.......... 4. ___Ramping___________________

3. The cold cleanup mode is used to start water circulating through the system. As the name implies, it also provides a time for water cleanup before firing the boiler. Boiler feedwater should be circulated until cation conductivity is less than one micromho.

4. The cold cleanup mode begins by pumping water through the unit, bringing it up to 33% of full load flow. Valves for the superheaters and turbines should be closed. Water should be directed to the high pressure heaters, the economizer, the furnace tubes, the convection pass, and the flashtank. From the flashtank, the water is sent to the condenser and condensate polisher for water cleanup and back to the feed pump.

5. Hot cleanup is very similar to the cold cleanup phase. A major difference is that in hot cleanup, the unit is fired. This means that steam is being generated. Also in hot cleanup, steam is admitted to the primary superheater. Another difference is that since steam is being produced and sent to the flashtank, the 242 valve was allowed to open. This flashtank steam control valve helps control steam pressure in the flashtank and also provides heat recovery in the high pressure heaters and deaerator.

------------------------------------------------- 22 ------------------------------------------------------

#BoilerManual #BypassSystem #Section7 #Page22

Answers for bypass system

1. Before universal pressure boilers can be fired, a minimum feedwater flow must be established. This is accomplished by the use of the bypass system.

2. The four modes of boiler operation are:

.......... 1. ___Cold Cleanup_______________

.......... 2. ___Hot Cleanup________________

.......... 3. ___Startup____________________

.......... 4. ___Ramping___________________

3. The cold cleanup mode is used to start water circulating through the system. As the name implies, it also provides a time for water cleanup before firing the boiler. Boiler feedwater should be circulated until cation conductivity is less than one micromho.

4. The cold cleanup mode begins by pumping water through the unit, bringing it up to 33% of full load flow. Valves for the superheaters and turbines should be closed. Water should be directed to the high pressure heaters, the economizer, the furnace tubes, the convection pass, and the flashtank. From the flashtank, the water is sent to the condenser and condensate polisher for water cleanup and back to the feed pump.

5. Hot cleanup is very similar to the cold cleanup phase. A major difference is that in hot cleanup, the unit is fired. This means that steam is being generated. Also in hot cleanup, steam is admitted to the primary superheater. Another difference is that since steam is being produced and sent to the flashtank, the 242 valve was allowed to open. This flashtank steam control valve helps control steam pressure in the flashtank and also provides heat recovery in the high pressure heaters and deaerator.

------------------------------------------------- 22 ------------------------------------------------------

#BoilerManual #BypassSystem #Section7 #Page22

Answers for bypass system

1. Before universal pressure boilers can be fired, a minimum feedwater flow must be established. This is accomplished by the use of the bypass system.

2. The four modes of boiler operation are:

.......... 1. ___Cold Cleanup_______________

.......... 2. ___Hot Cleanup________________

.......... 3. ___Startup____________________

.......... 4. ___Ramping___________________

3. The cold cleanup mode is used to start water circulating through the system. As the name implies, it also provides a time for water cleanup before firing the boiler. Boiler feedwater should be circulated until cation conductivity is less than one micromho.

4. The cold cleanup mode begins by pumping water through the unit, bringing it up to 33% of full load flow. Valves for the superheaters and turbines should be closed. Water should be directed to the high pressure heaters, the economizer, the furnace tubes, the convection pass, and the flashtank. From the flashtank, the water is sent to the condenser and condensate polisher for water cleanup and back to the feed pump.

5. Hot cleanup is very similar to the cold cleanup phase. A major difference is that in hot cleanup, the unit is fired. This means that steam is being generated. Also in hot cleanup, steam is admitted to the primary superheater. Another difference is that since steam is being produced and sent to the flashtank, the 242 valve was allowed to open. This flashtank steam control valve helps control steam pressure in the flashtank and also provides heat recovery in the high pressure heaters and deaerator.

------------------------------------------------- 22 ------------------------------------------------------

#BoilerManual #BypassSystem #Section7 #Page22

Answers for bypass system

1. Before universal pressure boilers can be fired, a minimum feedwater flow must be established. This is accomplished by the use of the bypass system.

2. The four modes of boiler operation are:

.......... 1. ___Cold Cleanup_______________

.......... 2. ___Hot Cleanup________________

.......... 3. ___Startup____________________

.......... 4. ___Ramping___________________

3. The cold cleanup mode is used to start water circulating through the system. As the name implies, it also provides a time for water cleanup before firing the boiler. Boiler feedwater should be circulated until cation conductivity is less than one micromho.

4. The cold cleanup mode begins by pumping water through the unit, bringing it up to 33% of full load flow. Valves for the superheaters and turbines should be closed. Water should be directed to the high pressure heaters, the economizer, the furnace tubes, the convection pass, and the flashtank. From the flashtank, the water is sent to the condenser and condensate polisher for water cleanup and back to the feed pump.

5. Hot cleanup is very similar to the cold cleanup phase. A major difference is that in hot cleanup, the unit is fired. This means that steam is being generated. Also in hot cleanup, steam is admitted to the primary superheater. Another difference is that since steam is being produced and sent to the flashtank, the 242 valve was allowed to open. This flashtank steam control valve helps control steam pressure in the flashtank and also provides heat recovery in the high pressure heaters and deaerator.

------------------------------------------------- 22 ------------------------------------------------------

#BoilerManual #BypassSystem #Section7 #Page22

Answers for bypass system

1. Before universal pressure boilers can be fired, a minimum feedwater flow must be established. This is accomplished by the use of the bypass system.

2. The four modes of boiler operation are:

.......... 1. ___Cold Cleanup_______________

.......... 2. ___Hot Cleanup________________

.......... 3. ___Startup____________________

.......... 4. ___Ramping___________________

3. The cold cleanup mode is used to start water circulating through the system. As the name implies, it also provides a time for water cleanup before firing the boiler. Boiler feedwater should be circulated until cation conductivity is less than one micromho.

4. The cold cleanup mode begins by pumping water through the unit, bringing it up to 33% of full load flow. Valves for the superheaters and turbines should be closed. Water should be directed to the high pressure heaters, the economizer, the furnace tubes, the convection pass, and the flashtank. From the flashtank, the water is sent to the condenser and condensate polisher for water cleanup and back to the feed pump.

5. Hot cleanup is very similar to the cold cleanup phase. A major difference is that in hot cleanup, the unit is fired. This means that steam is being generated. Also in hot cleanup, steam is admitted to the primary superheater. Another difference is that since steam is being produced and sent to the flashtank, the 242 valve was allowed to open. This flashtank steam control valve helps control steam pressure in the flashtank and also provides heat recovery in the high pressure heaters and deaerator.

------------------------------------------------- 22 ------------------------------------------------------

#BoilerManual #BypassSystem #Section7 #Page21

8. What is the ramping stage of boiler startup?

9. When can the hot cleanup phase be eliminated from the startup procedure?

------------------------------------------------- 21 ------------------------------------------------------

#BoilerManual #BypassSystem #Section7 #Page21

8. What is the ramping stage of boiler startup?

9. When can the hot cleanup phase be eliminated from the startup procedure?

------------------------------------------------- 21 ------------------------------------------------------

#BoilerManual #BypassSystem #Section7 #Page21

8. What is the ramping stage of boiler startup?

9. When can the hot cleanup phase be eliminated from the startup procedure?

------------------------------------------------- 21 ------------------------------------------------------

#BoilerManual #BypassSystem #Section7 #Page21

8. What is the ramping stage of boiler startup?

9. When can the hot cleanup phase be eliminated from the startup procedure?

------------------------------------------------- 21 ------------------------------------------------------

#BoilerManual #BypassSystem #Section7 #Page21

8. What is the ramping stage of boiler startup?

9. When can the hot cleanup phase be eliminated from the startup procedure?

------------------------------------------------- 21 ------------------------------------------------------

#BoilerManual #BypassSystem #Section7 #Page20

Questions for bypass system

1. Why is a bypass system needed for the universal pressure boiler?

2. Name the four different phases or modes of boiler operation during the bypass
system.

.......... 1. ________________________________

.......... 2. ________________________________

.......... 3. ________________________________

.......... 4. ________________________________

3. What are the main purposes of cold cleanup?

4. Briefly describe the cold cleanup mode of the boiler startup.

5. Briefly describe the hot cleanup phase.

6. When can the startup phase begin?

7. Briefly describe the startup phase.

------------------------------------------------- 20 ------------------------------------------------------

#BoilerManual #BypassSystem #Section7 #Page20

Questions for bypass system

1. Why is a bypass system needed for the universal pressure boiler?

2. Name the four different phases or modes of boiler operation during the bypass
system.

.......... 1. ________________________________

.......... 2. ________________________________

.......... 3. ________________________________

.......... 4. ________________________________

3. What are the main purposes of cold cleanup?

4. Briefly describe the cold cleanup mode of the boiler startup.

5. Briefly describe the hot cleanup phase.

6. When can the startup phase begin?

7. Briefly describe the startup phase.

------------------------------------------------- 20 ------------------------------------------------------

#BoilerManual #BypassSystem #Section7 #Page20

Questions for bypass system

1. Why is a bypass system needed for the universal pressure boiler?

2. Name the four different phases or modes of boiler operation during the bypass
system.

.......... 1. ________________________________

.......... 2. ________________________________

.......... 3. ________________________________

.......... 4. ________________________________

3. What are the main purposes of cold cleanup?

4. Briefly describe the cold cleanup mode of the boiler startup.

5. Briefly describe the hot cleanup phase.

6. When can the startup phase begin?

7. Briefly describe the startup phase.

------------------------------------------------- 20 ------------------------------------------------------

#BoilerManual #BypassSystem #Section7 #Page20

Questions for bypass system

1. Why is a bypass system needed for the universal pressure boiler?

2. Name the four different phases or modes of boiler operation during the bypass
system.

.......... 1. ________________________________

.......... 2. ________________________________

.......... 3. ________________________________

.......... 4. ________________________________

3. What are the main purposes of cold cleanup?

4. Briefly describe the cold cleanup mode of the boiler startup.

5. Briefly describe the hot cleanup phase.

6. When can the startup phase begin?

7. Briefly describe the startup phase.

------------------------------------------------- 20 ------------------------------------------------------

#BoilerManual #BypassSystem #Section7 #Page20

Questions for bypass system

1. Why is a bypass system needed for the universal pressure boiler?

2. Name the four different phases or modes of boiler operation during the bypass
system.

.......... 1. ________________________________

.......... 2. ________________________________

.......... 3. ________________________________

.......... 4. ________________________________

3. What are the main purposes of cold cleanup?

4. Briefly describe the cold cleanup mode of the boiler startup.

5. Briefly describe the hot cleanup phase.

6. When can the startup phase begin?

7. Briefly describe the startup phase.

------------------------------------------------- 20 ------------------------------------------------------

#BoilerManual #BypassSystem #Section7 #Page19

recovery. When the capacity of the 220 valve has been exhausted, valve 240 will open and pass steam to the condenser as required to maintain flashtank pressure.

Flashtank pressure reaches its setpoint of 500 psi. Steam flow through the SSH increases to approximately 4% of full load flow and is admitted to the turbine for rolling to synchronous speed.

As increased flashtank steam becomes available, the high pressure heater steam control valve, 220, will open. The high pressure heater will reach an operating pressure of 450 psi. Heater drains return flow to the condenser. At this point, the main steam line drain valve, MS-2, can be closed.

Throughout the warmup period, it is very important to monitor the water quality. If the proper water quality is not obtained, ti will be necessary to initiate a hold in the startup.

We have discussed the various stages of t he startup Bypass System from initial circulation to rolling of the turbine. The remaining portion of startup ramping will be discussed in a following section.

------------------------------------------------- 19 ------------------------------------------------------

#BoilerManual #BypassSystem #Section7 #Page19

recovery. When the capacity of the 220 valve has been exhausted, valve 240 will open and pass steam to the condenser as required to maintain flashtank pressure.

Flashtank pressure reaches its setpoint of 500 psi. Steam flow through the SSH increases to approximately 4% of full load flow and is admitted to the turbine for rolling to synchronous speed.

As increased flashtank steam becomes available, the high pressure heater steam control valve, 220, will open. The high pressure heater will reach an operating pressure of 450 psi. Heater drains return flow to the condenser. At this point, the main steam line drain valve, MS-2, can be closed.

Throughout the warmup period, it is very important to monitor the water quality. If the proper water quality is not obtained, ti will be necessary to initiate a hold in the startup.

We have discussed the various stages of t he startup Bypass System from initial circulation to rolling of the turbine. The remaining portion of startup ramping will be discussed in a following section.

------------------------------------------------- 19 ------------------------------------------------------

#BoilerManual #BypassSystem #Section7 #Page19

recovery. When the capacity of the 220 valve has been exhausted, valve 240 will open and pass steam to the condenser as required to maintain flashtank pressure.

Flashtank pressure reaches its setpoint of 500 psi. Steam flow through the SSH increases to approximately 4% of full load flow and is admitted to the turbine for rolling to synchronous speed.

As increased flashtank steam becomes available, the high pressure heater steam control valve, 220, will open. The high pressure heater will reach an operating pressure of 450 psi. Heater drains return flow to the condenser. At this point, the main steam line drain valve, MS-2, can be closed.

Throughout the warmup period, it is very important to monitor the water quality. If the proper water quality is not obtained, ti will be necessary to initiate a hold in the startup.

We have discussed the various stages of t he startup Bypass System from initial circulation to rolling of the turbine. The remaining portion of startup ramping will be discussed in a following section.

------------------------------------------------- 19 ------------------------------------------------------

#BoilerManual #BypassSystem #Section7 #Page19

recovery. When the capacity of the 220 valve has been exhausted, valve 240 will open and pass steam to the condenser as required to maintain flashtank pressure.

Flashtank pressure reaches its setpoint of 500 psi. Steam flow through the SSH increases to approximately 4% of full load flow and is admitted to the turbine for rolling to synchronous speed.

As increased flashtank steam becomes available, the high pressure heater steam control valve, 220, will open. The high pressure heater will reach an operating pressure of 450 psi. Heater drains return flow to the condenser. At this point, the main steam line drain valve, MS-2, can be closed.

Throughout the warmup period, it is very important to monitor the water quality. If the proper water quality is not obtained, ti will be necessary to initiate a hold in the startup.

We have discussed the various stages of t he startup Bypass System from initial circulation to rolling of the turbine. The remaining portion of startup ramping will be discussed in a following section.

------------------------------------------------- 19 ------------------------------------------------------

#BoilerManual #BypassSystem #Section7 #Page19

recovery. When the capacity of the 220 valve has been exhausted, valve 240 will open and pass steam to the condenser as required to maintain flashtank pressure.

Flashtank pressure reaches its setpoint of 500 psi. Steam flow through the SSH increases to approximately 4% of full load flow and is admitted to the turbine for rolling to synchronous speed.

As increased flashtank steam becomes available, the high pressure heater steam control valve, 220, will open. The high pressure heater will reach an operating pressure of 450 psi. Heater drains return flow to the condenser. At this point, the main steam line drain valve, MS-2, can be closed.

Throughout the warmup period, it is very important to monitor the water quality. If the proper water quality is not obtained, ti will be necessary to initiate a hold in the startup.

We have discussed the various stages of t he startup Bypass System from initial circulation to rolling of the turbine. The remaining portion of startup ramping will be discussed in a following section.

------------------------------------------------- 19 ------------------------------------------------------

#BoilerManual #BypassSystem #Section7 #Page18

Flashtank level will be established when the temperature of the fluid reaches 298 F. Valve 241 drains to the condenser and maintains flashtank level about -3" below centerline. This valve modulates between wide open at +1" and fully closed at -7". Flow and firing continues to increase flashtank pressure. Flow and firing continues to increase flashtank pressure. When flashtank pressure reaches 120 psi and a level has been established, the steam line block valve, 242, will open. At this point the deaerator steam pegging valve, 231, will control deaerator pressure at 42 psi. With the deaerator pegged at 42 psi by flashtank steam all flashtank drain flow is diverted to the condenser for polishing and water cleanup.

Flow and firing continues as before. When the fluid temperature at the boiler outlet reaches 300 F the boiler pressure is increased on a controlled ramp to 2550 psi. Pressure is controlled by the PSH bypass valve, 202. The SSH bypass valve, 207, will open to a minimum position and control the fluid temperature to 700 F at the PSH outlet. Before exceeding a fluid temperature of 550 F at the PSH bypass, 202, the feedwater iron content should not exceed 100 ppb.

When the flashtank pressure reaches 300 pis the low pressure stop valve, 205, will open to permit approximately 2% of full load steam to flow to the SSH for steam line warming. Since it is a stop check valve, it will close when the superheater pressure is higher than flashtank pressure. Minimum flow through the SSH is established using the turbine stop valve above seat drain, steam to boiler feed pump drains, and the main steam line drain valve, MS-2. After the steam line is warmed, flashtank pressure will continue to rise to its setpoint pressure which is determined by turbine throttle set point and controlled, first by steam control valves to the heaters, and second by the flashtank overpressure control valve which sends excess steam to the condenser.

The high pressure heater steam control valve, 220, is permitted to open when flashtank pressure reaches its setpoint (500 psi). Steam is discharged from flashtank to the "G" high pressure heaters for heat

------------------------------------------------- 18 ------------------------------------------------------

#BoilerManual #BypassSystem #Section7 #Page18

Flashtank level will be established when the temperature of the fluid reaches 298 F. Valve 241 drains to the condenser and maintains flashtank level about -3" below centerline. This valve modulates between wide open at +1" and fully closed at -7". Flow and firing continues to increase flashtank pressure. Flow and firing continues to increase flashtank pressure. When flashtank pressure reaches 120 psi and a level has been established, the steam line block valve, 242, will open. At this point the deaerator steam pegging valve, 231, will control deaerator pressure at 42 psi. With the deaerator pegged at 42 psi by flashtank steam all flashtank drain flow is diverted to the condenser for polishing and water cleanup.

Flow and firing continues as before. When the fluid temperature at the boiler outlet reaches 300 F the boiler pressure is increased on a controlled ramp to 2550 psi. Pressure is controlled by the PSH bypass valve, 202. The SSH bypass valve, 207, will open to a minimum position and control the fluid temperature to 700 F at the PSH outlet. Before exceeding a fluid temperature of 550 F at the PSH bypass, 202, the feedwater iron content should not exceed 100 ppb.

When the flashtank pressure reaches 300 pis the low pressure stop valve, 205, will open to permit approximately 2% of full load steam to flow to the SSH for steam line warming. Since it is a stop check valve, it will close when the superheater pressure is higher than flashtank pressure. Minimum flow through the SSH is established using the turbine stop valve above seat drain, steam to boiler feed pump drains, and the main steam line drain valve, MS-2. After the steam line is warmed, flashtank pressure will continue to rise to its setpoint pressure which is determined by turbine throttle set point and controlled, first by steam control valves to the heaters, and second by the flashtank overpressure control valve which sends excess steam to the condenser.

The high pressure heater steam control valve, 220, is permitted to open when flashtank pressure reaches its setpoint (500 psi). Steam is discharged from flashtank to the "G" high pressure heaters for heat

------------------------------------------------- 18 ------------------------------------------------------

#BoilerManual #BypassSystem #Section7 #Page18

Flashtank level will be established when the temperature of the fluid reaches 298 F. Valve 241 drains to the condenser and maintains flashtank level about -3" below centerline. This valve modulates between wide open at +1" and fully closed at -7". Flow and firing continues to increase flashtank pressure. Flow and firing continues to increase flashtank pressure. When flashtank pressure reaches 120 psi and a level has been established, the steam line block valve, 242, will open. At this point the deaerator steam pegging valve, 231, will control deaerator pressure at 42 psi. With the deaerator pegged at 42 psi by flashtank steam all flashtank drain flow is diverted to the condenser for polishing and water cleanup.

Flow and firing continues as before. When the fluid temperature at the boiler outlet reaches 300 F the boiler pressure is increased on a controlled ramp to 2550 psi. Pressure is controlled by the PSH bypass valve, 202. The SSH bypass valve, 207, will open to a minimum position and control the fluid temperature to 700 F at the PSH outlet. Before exceeding a fluid temperature of 550 F at the PSH bypass, 202, the feedwater iron content should not exceed 100 ppb.

When the flashtank pressure reaches 300 pis the low pressure stop valve, 205, will open to permit approximately 2% of full load steam to flow to the SSH for steam line warming. Since it is a stop check valve, it will close when the superheater pressure is higher than flashtank pressure. Minimum flow through the SSH is established using the turbine stop valve above seat drain, steam to boiler feed pump drains, and the main steam line drain valve, MS-2. After the steam line is warmed, flashtank pressure will continue to rise to its setpoint pressure which is determined by turbine throttle set point and controlled, first by steam control valves to the heaters, and second by the flashtank overpressure control valve which sends excess steam to the condenser.

The high pressure heater steam control valve, 220, is permitted to open when flashtank pressure reaches its setpoint (500 psi). Steam is discharged from flashtank to the "G" high pressure heaters for heat

------------------------------------------------- 18 ------------------------------------------------------

#BoilerManual #BypassSystem #Section7 #Page18

Flashtank level will be established when the temperature of the fluid reaches 298 F. Valve 241 drains to the condenser and maintains flashtank level about -3" below centerline. This valve modulates between wide open at +1" and fully closed at -7". Flow and firing continues to increase flashtank pressure. Flow and firing continues to increase flashtank pressure. When flashtank pressure reaches 120 psi and a level has been established, the steam line block valve, 242, will open. At this point the deaerator steam pegging valve, 231, will control deaerator pressure at 42 psi. With the deaerator pegged at 42 psi by flashtank steam all flashtank drain flow is diverted to the condenser for polishing and water cleanup.

Flow and firing continues as before. When the fluid temperature at the boiler outlet reaches 300 F the boiler pressure is increased on a controlled ramp to 2550 psi. Pressure is controlled by the PSH bypass valve, 202. The SSH bypass valve, 207, will open to a minimum position and control the fluid temperature to 700 F at the PSH outlet. Before exceeding a fluid temperature of 550 F at the PSH bypass, 202, the feedwater iron content should not exceed 100 ppb.

When the flashtank pressure reaches 300 pis the low pressure stop valve, 205, will open to permit approximately 2% of full load steam to flow to the SSH for steam line warming. Since it is a stop check valve, it will close when the superheater pressure is higher than flashtank pressure. Minimum flow through the SSH is established using the turbine stop valve above seat drain, steam to boiler feed pump drains, and the main steam line drain valve, MS-2. After the steam line is warmed, flashtank pressure will continue to rise to its setpoint pressure which is determined by turbine throttle set point and controlled, first by steam control valves to the heaters, and second by the flashtank overpressure control valve which sends excess steam to the condenser.

The high pressure heater steam control valve, 220, is permitted to open when flashtank pressure reaches its setpoint (500 psi). Steam is discharged from flashtank to the "G" high pressure heaters for heat

------------------------------------------------- 18 ------------------------------------------------------

#BoilerManual #BypassSystem #Section7 #Page18

Flashtank level will be established when the temperature of the fluid reaches 298 F. Valve 241 drains to the condenser and maintains flashtank level about -3" below centerline. This valve modulates between wide open at +1" and fully closed at -7". Flow and firing continues to increase flashtank pressure. Flow and firing continues to increase flashtank pressure. When flashtank pressure reaches 120 psi and a level has been established, the steam line block valve, 242, will open. At this point the deaerator steam pegging valve, 231, will control deaerator pressure at 42 psi. With the deaerator pegged at 42 psi by flashtank steam all flashtank drain flow is diverted to the condenser for polishing and water cleanup.

Flow and firing continues as before. When the fluid temperature at the boiler outlet reaches 300 F the boiler pressure is increased on a controlled ramp to 2550 psi. Pressure is controlled by the PSH bypass valve, 202. The SSH bypass valve, 207, will open to a minimum position and control the fluid temperature to 700 F at the PSH outlet. Before exceeding a fluid temperature of 550 F at the PSH bypass, 202, the feedwater iron content should not exceed 100 ppb.

When the flashtank pressure reaches 300 pis the low pressure stop valve, 205, will open to permit approximately 2% of full load steam to flow to the SSH for steam line warming. Since it is a stop check valve, it will close when the superheater pressure is higher than flashtank pressure. Minimum flow through the SSH is established using the turbine stop valve above seat drain, steam to boiler feed pump drains, and the main steam line drain valve, MS-2. After the steam line is warmed, flashtank pressure will continue to rise to its setpoint pressure which is determined by turbine throttle set point and controlled, first by steam control valves to the heaters, and second by the flashtank overpressure control valve which sends excess steam to the condenser.

The high pressure heater steam control valve, 220, is permitted to open when flashtank pressure reaches its setpoint (500 psi). Steam is discharged from flashtank to the "G" high pressure heaters for heat

------------------------------------------------- 18 ------------------------------------------------------

#BoilerManual #BypassSystem #Section7 #Page17

------------------------------------------------- 17 ------------------------------------------------------
Alt = Labeled Fig. 4F Startup -- Turbine synchronized. Image is sideways, of course, with the bottom long the right edge and the top along the left edge, and resembles the others in this series but at this point the system as a whole is involved, with focus on the turbine. Please see the main text for details.

#BoilerManual #BypassSystem #Section7 #Page17

------------------------------------------------- 17 ------------------------------------------------------
Alt = Labeled Fig. 4F Startup -- Turbine synchronized. Image is sideways, of course, with the bottom long the right edge and the top along the left edge, and resembles the others in this series but at this point the system as a whole is involved, with focus on the turbine. Please see the main text for details.

#BoilerManual #BypassSystem #Section7 #Page17

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Alt = Labeled Fig. 4F Startup -- Turbine synchronized. Image is sideways, of course, with the bottom long the right edge and the top along the left edge, and resembles the others in this series but at this point the system as a whole is involved, with focus on the turbine. Please see the main text for details.

#BoilerManual #BypassSystem #Section7 #Page17

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Alt = Labeled Fig. 4F Startup -- Turbine synchronized. Image is sideways, of course, with the bottom long the right edge and the top along the left edge, and resembles the others in this series but at this point the system as a whole is involved, with focus on the turbine. Please see the main text for details.

#BoilerManual #BypassSystem #Section7 #Page17

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Alt = Labeled Fig. 4F Startup -- Turbine synchronized. Image is sideways, of course, with the bottom long the right edge and the top along the left edge, and resembles the others in this series but at this point the system as a whole is involved, with focus on the turbine. Please see the main text for details.

#BoilerManual #BypassSystem #Section7 #Page16

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Alt = Labeled Fig. 4E Startup -- Turbine rolling. As before, this image is sideways with the bottom long the right edge and the top along the left edge and resembles the others in this series with the difference being that valve status has changed, focus is on the turbine, best described in the main text.

#BoilerManual #BypassSystem #Section7 #Page16

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Alt = Labeled Fig. 4E Startup -- Turbine rolling. As before, this image is sideways with the bottom long the right edge and the top along the left edge and resembles the others in this series with the difference being that valve status has changed, focus is on the turbine, best described in the main text.

#BoilerManual #BypassSystem #Section7 #Page16

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Alt = Labeled Fig. 4E Startup -- Turbine rolling. As before, this image is sideways with the bottom long the right edge and the top along the left edge and resembles the others in this series with the difference being that valve status has changed, focus is on the turbine, best described in the main text.

#BoilerManual #BypassSystem #Section7 #Page16

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Alt = Labeled Fig. 4E Startup -- Turbine rolling. As before, this image is sideways with the bottom long the right edge and the top along the left edge and resembles the others in this series with the difference being that valve status has changed, focus is on the turbine, best described in the main text.

#BoilerManual #BypassSystem #Section7 #Page16

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Alt = Labeled Fig. 4E Startup -- Turbine rolling. As before, this image is sideways with the bottom long the right edge and the top along the left edge and resembles the others in this series with the difference being that valve status has changed, focus is on the turbine, best described in the main text.

#BoilerManual #BypassSystem #Section7 #Page15

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Alt = Labeled Fig. 4D Startup -- Steam line warming. This image is sideways with the bottom long the right edge and the top along the left edge and is best described in the main text when it refers to this image. The Secondary Suprheater is now involved.

#BoilerManual #BypassSystem #Section7 #Page15

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Alt = Labeled Fig. 4D Startup -- Steam line warming. This image is sideways with the bottom long the right edge and the top along the left edge and is best described in the main text when it refers to this image. The Secondary Suprheater is now involved.

#BoilerManual #BypassSystem #Section7 #Page15

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Alt = Labeled Fig. 4D Startup -- Steam line warming. This image is sideways with the bottom long the right edge and the top along the left edge and is best described in the main text when it refers to this image. The Secondary Suprheater is now involved.

#BoilerManual #BypassSystem #Section7 #Page15

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Alt = Labeled Fig. 4D Startup -- Steam line warming. This image is sideways with the bottom long the right edge and the top along the left edge and is best described in the main text when it refers to this image. The Secondary Suprheater is now involved.

#BoilerManual #BypassSystem #Section7 #Page15

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Alt = Labeled Fig. 4D Startup -- Steam line warming. This image is sideways with the bottom long the right edge and the top along the left edge and is best described in the main text when it refers to this image. The Secondary Suprheater is now involved.

#BoilerManual #BypassSystem #Section7 #Page14

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Alt = Labeled Fig. 4C Startup -- Pressure and temperature control. The image is, like the others in this set, sideways with the bottom long the right edge and the top along the left edge, and identical to the others in this set except in this one, the Primary Superheater (PSH) is more involved as depicted by the heavy lines drawn to it. Again, it's the main text that describes best what is happening here.
to it. Again, it's the main text that describes best what is happening here.

#BoilerManual #BypassSystem #Section7 #Page14

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Alt = Labeled Fig. 4C Startup -- Pressure and temperature control. The image is, like the others in this set, sideways with the bottom long the right edge and the top along the left edge, and identical to the others in this set except in this one, the Primary Superheater (PSH) is more involved as depicted by the heavy lines drawn to it. Again, it's the main text that describes best what is happening here.
to it. Again, it's the main text that describes best what is happening here.

#BoilerManual #BypassSystem #Section7 #Page14

------------------------------------------------- 14 ------------------------------------------------------
Alt = Labeled Fig. 4C Startup -- Pressure and temperature control. The image is, like the others in this set, sideways with the bottom long the right edge and the top along the left edge, and identical to the others in this set except in this one, the Primary Superheater (PSH) is more involved as depicted by the heavy lines drawn to it. Again, it's the main text that describes best what is happening here.
to it. Again, it's the main text that describes best what is happening here.

#BoilerManual #BypassSystem #Section7 #Page14

------------------------------------------------- 14 ------------------------------------------------------
Alt = Labeled Fig. 4C Startup -- Pressure and temperature control. The image is, like the others in this set, sideways with the bottom long the right edge and the top along the left edge, and identical to the others in this set except in this one, the Primary Superheater (PSH) is more involved as depicted by the heavy lines drawn to it. Again, it's the main text that describes best what is happening here.
to it. Again, it's the main text that describes best what is happening here.

#BoilerManual #BypassSystem #Section7 #Page14

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Alt = Labeled Fig. 4C Startup -- Pressure and temperature control. The image is, like the others in this set, sideways with the bottom long the right edge and the top along the left edge, and identical to the others in this set except in this one, the Primary Superheater (PSH) is more involved as depicted by the heavy lines drawn to it. Again, it's the main text that describes best what is happening here.
to it. Again, it's the main text that describes best what is happening here.

#BoilerManual #BypassSystem #Section7 #Page13

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Alt = Labeled Fig. 4B Startup -- Deaerator pressurization. This image is also sideways with the bottom long the right edge and the top along the left edge, and nearly identical to the previous simplified figures but with a focus on the different valving configuration covered in detail in the main text.

#BoilerManual #BypassSystem #Section7 #Page13

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Alt = Labeled Fig. 4B Startup -- Deaerator pressurization. This image is also sideways with the bottom long the right edge and the top along the left edge, and nearly identical to the previous simplified figures but with a focus on the different valving configuration covered in detail in the main text.

#BoilerManual #BypassSystem #Section7 #Page13

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Alt = Labeled Fig. 4B Startup -- Deaerator pressurization. This image is also sideways with the bottom long the right edge and the top along the left edge, and nearly identical to the previous simplified figures but with a focus on the different valving configuration covered in detail in the main text.

#BoilerManual #BypassSystem #Section7 #Page13

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Alt = Labeled Fig. 4B Startup -- Deaerator pressurization. This image is also sideways with the bottom long the right edge and the top along the left edge, and nearly identical to the previous simplified figures but with a focus on the different valving configuration covered in detail in the main text.

#BoilerManual #BypassSystem #Section7 #Page13

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Alt = Labeled Fig. 4B Startup -- Deaerator pressurization. This image is also sideways with the bottom long the right edge and the top along the left edge, and nearly identical to the previous simplified figures but with a focus on the different valving configuration covered in detail in the main text.

#BoilerManual #BypassSystem #Section7 #Page12

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Alt = Labeled Fig. 4A Startup -- Initial firing. This image is also sideways with the bottom along the right edge and the top along the left edge, and it's like Fig. 3 but with a different valve focus, correspondent to the main text at this point.

#BoilerManual #BypassSystem #Section7 #Page12

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Alt = Labeled Fig. 4A Startup -- Initial firing. This image is also sideways with the bottom along the right edge and the top along the left edge, and it's like Fig. 3 but with a different valve focus, correspondent to the main text at this point.

#BoilerManual #BypassSystem #Section7 #Page12

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Alt = Labeled Fig. 4A Startup -- Initial firing. This image is also sideways with the bottom along the right edge and the top along the left edge, and it's like Fig. 3 but with a different valve focus, correspondent to the main text at this point.

#BoilerManual #BypassSystem #Section7 #Page12

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Alt = Labeled Fig. 4A Startup -- Initial firing. This image is also sideways with the bottom along the right edge and the top along the left edge, and it's like Fig. 3 but with a different valve focus, correspondent to the main text at this point.

#BoilerManual #BypassSystem #Section7 #Page12

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Alt = Labeled Fig. 4A Startup -- Initial firing. This image is also sideways with the bottom along the right edge and the top along the left edge, and it's like Fig. 3 but with a different valve focus, correspondent to the main text at this point.