#section-8 — Public Fediverse posts

#BoilerManual #Ramping #Section8 #Page25

Answers for ramping

1. When load is at 10% and flashtank steam is 500 psi, the ramp is begun.

2. The 205 valve controls flow from the flashtank to the turbine.

3. False.
You must get 700 F and wait until the temperature has stabilized before proceeding with the ramp.

4. The operator sets the megawatt demand station for final load and load rate of change.

5. Early in the ramp, firing rate is based on gas temperature. After the thermoprobes retract, firing rate is based on main steam temperature.

6. The ramp begins at Point C.

7. The turbine is in automatic and megawatt demand is increased to 33% of full load flow.

8. The 202 and 207 valves close to maintain 33% boiler flow as the 201 opens to increase turbine flow. Closing of the the 202 and 207 valves reduce flow to the flashtank to compensate.

9. Since steam flow changes faster than firing rate, the firing must be kept above desired steam flow.

10. The steam temperature at the primary superheater and convection pass outlets are firing rate indicators.

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#BoilerManual #Ramping #Section8 #Page25

Answers for ramping

1. When load is at 10% and flashtank steam is 500 psi, the ramp is begun.

2. The 205 valve controls flow from the flashtank to the turbine.

3. False.
You must get 700 F and wait until the temperature has stabilized before proceeding with the ramp.

4. The operator sets the megawatt demand station for final load and load rate of change.

5. Early in the ramp, firing rate is based on gas temperature. After the thermoprobes retract, firing rate is based on main steam temperature.

6. The ramp begins at Point C.

7. The turbine is in automatic and megawatt demand is increased to 33% of full load flow.

8. The 202 and 207 valves close to maintain 33% boiler flow as the 201 opens to increase turbine flow. Closing of the the 202 and 207 valves reduce flow to the flashtank to compensate.

9. Since steam flow changes faster than firing rate, the firing must be kept above desired steam flow.

10. The steam temperature at the primary superheater and convection pass outlets are firing rate indicators.

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#BoilerManual #Ramping #Section8 #Page24

9. Why is actual firing rate kept above steady state?

10. In this graph, which two temperatures are an indication of firing rate?

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Alt = This chart for question 10 is identical to Fig. 8 on page 18.

#BoilerManual #Ramping #Section8 #Page24

9. Why is actual firing rate kept above steady state?

10. In this graph, which two temperatures are an indication of firing rate?

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Alt = This chart for question 10 is identical to Fig. 8 on page 18.

#BoilerManual #Ramping #Section8 #Page23

8. In this graph the 207 and 202 valves are closing. Why?

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Alt = The top chart on this page is addressed by question 7 on the previous page and the lines is identical to chart 6A of Fig. 6 on page 13 but with all but the line identification markings removed.
The lower chart associated with question 8 on this page is identical to chart 6C of Fig. 6 on page 13, complete with labels.

#BoilerManual #Ramping #Section8 #Page23

8. In this graph the 207 and 202 valves are closing. Why?

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Alt = The top chart on this page is addressed by question 7 on the previous page and the lines is identical to chart 6A of Fig. 6 on page 13 but with all but the line identification markings removed.
The lower chart associated with question 8 on this page is identical to chart 6C of Fig. 6 on page 13, complete with labels.

#BoilerManual #Ramping #Section8 #Page22

Questions for ramping

1. The ramp can be initiated when the unit load is ____% and there is ____ psi steam.

2. What valve controls flow from the flashtank to the turbine?

3. True or False.
With all other conditions met, the secondary superheater ramp may be started immediately after you get 700 F at the primary superheater outlet.

4. Many ramp conditions are automatic. What does the operator set?

5. On what do you base firing rate?

6. The ramp begins after the system has stabilized, the turbine is on _____________ and megawatt demand station is increased to _____________.

7. On this graph, at what point does the pressure ramp begin?

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#BoilerManual #Ramping #Section8 #Page22

Questions for ramping

1. The ramp can be initiated when the unit load is ____% and there is ____ psi steam.

2. What valve controls flow from the flashtank to the turbine?

3. True or False.
With all other conditions met, the secondary superheater ramp may be started immediately after you get 700 F at the primary superheater outlet.

4. Many ramp conditions are automatic. What does the operator set?

5. On what do you base firing rate?

6. The ramp begins after the system has stabilized, the turbine is on _____________ and megawatt demand station is increased to _____________.

7. On this graph, at what point does the pressure ramp begin?

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#BoilerManual #Ramping #Section8 #Page21

Again, the major problem with this ramp was the failure to establish proper pre-ramp conditions at the CP and PSH outlets. Had the proper temperatures been established and the boiler stable, the 207 valve would have been far enough open to compensate for the initial opening of the 201 valves and PSH outlet temperature would not have dropped. The resultant overfiring early in the ramp to raise that temperature could have been avoided.

The overfiring at the end of the ramp could also have been avoided if the firing rte had been reduced rather than increased, as the increasing CP and PSH temperatures indicated it should have been. Graphs in the control room of the proper firing rate, MW, and throttle pressure for each boiler master position certainly would have helped in avoiding this problem. {Such graphs were found in the control room at Baldwin for each unit, plotted out in real time via chart recorders. These gizmos consisted of an overhead ink pen tip touching a rather long scroll of graph paper loaded into them.}

You should now be able to understand the importance of maintaining proper pre-ramp conditions. The ramping process depends on the operation of many valves to maintain proper pressures and temperatures throughout the system for safe and efficient startups. A timely and orderly startup from bypass to ramping requires complete understanding of the operation of each valve and its function with the boiler cycle.

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#BoilerManual #Ramping #Section8 #Page21

Again, the major problem with this ramp was the failure to establish proper pre-ramp conditions at the CP and PSH outlets. Had the proper temperatures been established and the boiler stable, the 207 valve would have been far enough open to compensate for the initial opening of the 201 valves and PSH outlet temperature would not have dropped. The resultant overfiring early in the ramp to raise that temperature could have been avoided.

The overfiring at the end of the ramp could also have been avoided if the firing rte had been reduced rather than increased, as the increasing CP and PSH temperatures indicated it should have been. Graphs in the control room of the proper firing rate, MW, and throttle pressure for each boiler master position certainly would have helped in avoiding this problem. {Such graphs were found in the control room at Baldwin for each unit, plotted out in real time via chart recorders. These gizmos consisted of an overhead ink pen tip touching a rather long scroll of graph paper loaded into them.}

You should now be able to understand the importance of maintaining proper pre-ramp conditions. The ramping process depends on the operation of many valves to maintain proper pressures and temperatures throughout the system for safe and efficient startups. A timely and orderly startup from bypass to ramping requires complete understanding of the operation of each valve and its function with the boiler cycle.

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#BoilerManual #Ramping #Section8 #Page20

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Alt = Simply labeled Fig. 9, but the title at the top reads EXAMPLE: INCORRECT PRE-RAMP CONDITIONS. Like Fig. 6, this is a set of 3 charts with the x axis markings in common.

The y axis on the top chart is marked Valve position --%; it's set in increments of 20, and plot lines for, top down order, 202 valve, 201 valve, then to the left bottom the 207 valve and to the right bottom, the 2000 valve.

The middle chart's y axis is marked thrice over, first in terms of Boiler and firing rate master % next to the axis, incremented by 5s up to 20 and then an unmarked line across; to the left is marked corresponding Megawatts, in increments of 20s; further to the left of that is marked Throttle pressure, in corresponding terms from 500 to 2500 in increments. The lines appear intertwined but are distinguished from each other by type of line drawn.

Firing rate is drawn with alternating dashes and dots; Boiler master is short dashes; MW line is solid but appears intertwined with Boiler master. The lowest line is by itself, in a solid line, marked Throttle pressure.

The bottom chart's y axis is marked twice over, first as Convection pass and PSH outlet temperature, from 620 to 800 incremented in 20s; correspondingly marked to the left of that as SSH outlet temperature, from 800 to 1050 in increments of 50. The lines, in top down order, are PSH (drawn as an alternating dash dot line), SSH (drawn as a solid line), and Convection pass (drawn as a line of short dashes). What's going on is explained in detail by the main text.

#BoilerManual #Ramping #Section8 #Page20

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Alt = Simply labeled Fig. 9, but the title at the top reads EXAMPLE: INCORRECT PRE-RAMP CONDITIONS. Like Fig. 6, this is a set of 3 charts with the x axis markings in common.

The y axis on the top chart is marked Valve position --%; it's set in increments of 20, and plot lines for, top down order, 202 valve, 201 valve, then to the left bottom the 207 valve and to the right bottom, the 2000 valve.

The middle chart's y axis is marked thrice over, first in terms of Boiler and firing rate master % next to the axis, incremented by 5s up to 20 and then an unmarked line across; to the left is marked corresponding Megawatts, in increments of 20s; further to the left of that is marked Throttle pressure, in corresponding terms from 500 to 2500 in increments. The lines appear intertwined but are distinguished from each other by type of line drawn.

Firing rate is drawn with alternating dashes and dots; Boiler master is short dashes; MW line is solid but appears intertwined with Boiler master. The lowest line is by itself, in a solid line, marked Throttle pressure.

The bottom chart's y axis is marked twice over, first as Convection pass and PSH outlet temperature, from 620 to 800 incremented in 20s; correspondingly marked to the left of that as SSH outlet temperature, from 800 to 1050 in increments of 50. The lines, in top down order, are PSH (drawn as an alternating dash dot line), SSH (drawn as a solid line), and Convection pass (drawn as a line of short dashes). What's going on is explained in detail by the main text.

#BoilerManual #Ramping #Section8 #Page19

data shown in Figure 9. There was no stabilization period, which in this case was badly needed.

Convection pass outlet and PSH outlet temperatures were too low to begin the ramp. Since both temperatures were low, the 207 valve was further closed than it normally would be had proper pre-ramp conditions been established.

The initial opening of the 201 valves drove the 207 valve completely closed. The 207 valve could not compensate for the increased flow through the 201 due to the low initial temperatures. This resulted in a flow increase when there should have been merely and exchange. Due to the increased flow, PSH temperature dropped sharply approximately 15 minutes into the ramp. This was aggravated by the fact that the increased flow was from low temperature convection pass steam. Firing rate was increased drastically to offset the low PSH temperature. Convection pass temperature rose sharply 20-25 minutes into the ramp. Furnace circuit temperatures were not taken, but it is possible they were in alarm at this point.

Firing rate was lowered to near normal at 25 minutes and the system began to stabilize. From about 30 minutes on, the pressure ramp was fairly smooth, as convection pass temperature was sufficiently high. 202 and 201 valve actions stabilized, while MW and throttle pressure increased smoothly.

Temperature control was still not good, however. Firing rate was erroneously increased from 50 to 70 minutes at a time when it should have been leveled off as shown by the dotted line. The rising CP outlet and PSH temperatures should have indicated that firing needed to be held steady rather than increased. Main steam, PSH and CP outlet temperatures all went dangerously high, and in all probability, so did furnace circuit temperatures.

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#BoilerManual #Ramping #Section8 #Page19

data shown in Figure 9. There was no stabilization period, which in this case was badly needed.

Convection pass outlet and PSH outlet temperatures were too low to begin the ramp. Since both temperatures were low, the 207 valve was further closed than it normally would be had proper pre-ramp conditions been established.

The initial opening of the 201 valves drove the 207 valve completely closed. The 207 valve could not compensate for the increased flow through the 201 due to the low initial temperatures. This resulted in a flow increase when there should have been merely and exchange. Due to the increased flow, PSH temperature dropped sharply approximately 15 minutes into the ramp. This was aggravated by the fact that the increased flow was from low temperature convection pass steam. Firing rate was increased drastically to offset the low PSH temperature. Convection pass temperature rose sharply 20-25 minutes into the ramp. Furnace circuit temperatures were not taken, but it is possible they were in alarm at this point.

Firing rate was lowered to near normal at 25 minutes and the system began to stabilize. From about 30 minutes on, the pressure ramp was fairly smooth, as convection pass temperature was sufficiently high. 202 and 201 valve actions stabilized, while MW and throttle pressure increased smoothly.

Temperature control was still not good, however. Firing rate was erroneously increased from 50 to 70 minutes at a time when it should have been leveled off as shown by the dotted line. The rising CP outlet and PSH temperatures should have indicated that firing needed to be held steady rather than increased. Main steam, PSH and CP outlet temperatures all went dangerously high, and in all probability, so did furnace circuit temperatures.

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#BoilerManual #Ramping #Section8 #Page18

As the ramp progresses, flow through the SSH is increased and flow to the flashtank is decreased. With the decreased flow to the flashtank, flow is also reduced to the FW heaters and the DA so feedwater temperature will decrease. When flashtank pressure has decayed sufficiently, the heaters and DA will go on extraction steam and the FW temperature will begin to increase by the end of the ramp. The flashtank is kept warm by an interconnection with the deaerator via the 236 valve. Flashtank pressure will float with DA pressure.

EXAMPLE OF A RAMP WITH INCORRECT PRE-RAMP CONDITIONS

The following discussion will indicate the importance of stabilizing the system prior to the initiation of the ramp. The ramp in our example was initiated immediately after the initial opening of the 201 valve for the

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Alt = Labeled Fig. 8 Temperatures during the ramp. It's a chart where only the x axis and the lines for the 201 and 200 are identical to the previous charts. The y axis is marked Degrees F and is arbitrarily incremented in different but ascending spots as 380, 655, 710, 925, 950 and 1000. The corresponding lines drawn from those are, in ascending order, Feedwater temp., Convection pass outlet temperature, PSH outlet temperature, SSH outlet temperature and Gas temperature. Where each of those lines cross the x axis points of B, C, D and E are drawn with vertical dashed lines.

#BoilerManual #Ramping #Section8 #Page18

As the ramp progresses, flow through the SSH is increased and flow to the flashtank is decreased. With the decreased flow to the flashtank, flow is also reduced to the FW heaters and the DA so feedwater temperature will decrease. When flashtank pressure has decayed sufficiently, the heaters and DA will go on extraction steam and the FW temperature will begin to increase by the end of the ramp. The flashtank is kept warm by an interconnection with the deaerator via the 236 valve. Flashtank pressure will float with DA pressure.

EXAMPLE OF A RAMP WITH INCORRECT PRE-RAMP CONDITIONS

The following discussion will indicate the importance of stabilizing the system prior to the initiation of the ramp. The ramp in our example was initiated immediately after the initial opening of the 201 valve for the

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Alt = Labeled Fig. 8 Temperatures during the ramp. It's a chart where only the x axis and the lines for the 201 and 200 are identical to the previous charts. The y axis is marked Degrees F and is arbitrarily incremented in different but ascending spots as 380, 655, 710, 925, 950 and 1000. The corresponding lines drawn from those are, in ascending order, Feedwater temp., Convection pass outlet temperature, PSH outlet temperature, SSH outlet temperature and Gas temperature. Where each of those lines cross the x axis points of B, C, D and E are drawn with vertical dashed lines.

#BoilerManual #Ramping #Section8 #Page17

If for some reason the ramp must be interrupted, the MW demand station can be lowered to match the MW demand thus, stopping the gradual ramped increase in load demand. When the ramp must be stopped, firing rate may have to be manually lowered to near its steady state value, as shown at point X on Figure 7. (Note that for any given steam flow there is only one firing rate which will maintain the correct steam temperature and flow). When the ramp is resumed by raising the MW demand station to 33% of full load firing rate should again be increased.

The curve for the de-ramp is also shown in Figure 7. When de-ramping the unit, firing rate must be below its normal steady state value. Heat stored in the boiler tube metals would tend to make steam temperatures high if the normal steady state firing program was followed.

Plots of several of the more important temperatures are shown in Figure 8. All should be allowed to stabilize at the correct values prior to the initial opening of the 201 at point B. There should be very little change between point B and the initiation of the ramp at point
C.

Gas temperature should increase steadily from point C as firing rate is increased. The thermoprobes will retract when gas temperature reaches approximately 1200 F. At this point firing rate control is based on actual steam temperature. SSH outlet temperature should steadily increase from its initial value to final steam temperature at the end of the ramp.

Both PSH outlet and convection pass outlet temperatures should be relatively constant throughout the ramp and should be used as guides for alteration of the firing rate. Sharp changes in either temperature indicate the need for manual adjustment. Of course, PSH outlet temperature can only be used as an indication of firing rate after the 207 valve is completely closed.

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#BoilerManual #Ramping #Section8 #Page17

If for some reason the ramp must be interrupted, the MW demand station can be lowered to match the MW demand thus, stopping the gradual ramped increase in load demand. When the ramp must be stopped, firing rate may have to be manually lowered to near its steady state value, as shown at point X on Figure 7. (Note that for any given steam flow there is only one firing rate which will maintain the correct steam temperature and flow). When the ramp is resumed by raising the MW demand station to 33% of full load firing rate should again be increased.

The curve for the de-ramp is also shown in Figure 7. When de-ramping the unit, firing rate must be below its normal steady state value. Heat stored in the boiler tube metals would tend to make steam temperatures high if the normal steady state firing program was followed.

Plots of several of the more important temperatures are shown in Figure 8. All should be allowed to stabilize at the correct values prior to the initial opening of the 201 at point B. There should be very little change between point B and the initiation of the ramp at point
C.

Gas temperature should increase steadily from point C as firing rate is increased. The thermoprobes will retract when gas temperature reaches approximately 1200 F. At this point firing rate control is based on actual steam temperature. SSH outlet temperature should steadily increase from its initial value to final steam temperature at the end of the ramp.

Both PSH outlet and convection pass outlet temperatures should be relatively constant throughout the ramp and should be used as guides for alteration of the firing rate. Sharp changes in either temperature indicate the need for manual adjustment. Of course, PSH outlet temperature can only be used as an indication of firing rate after the 207 valve is completely closed.

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#BoilerManual #Ramping #Section8 #Page16

based on flue gas temperature during most of the ramp, then on actual main steam temperature after the gas temperature probes retract.

A typical plot of firing rte is shown in Figure 7. The system is allowed to stabilize from points A to B. At point B, after steady state conditions are reached, the turbine load is manually increased causing thte 201 valve to begin opening. At point C, the turbine is automated and the MW demand station increased, initiating the ramp.

Notice that from point C to the end of the ramp at point E, there are three curves for firing rate.

During a continuous ramp, the system never reaches steady state. This means there is a continuous demand for steam flow and firing rate is being increased at this time. Because the steam flow changes faster than firing rate can change, a drop would develop in steam temperature if corrective measures were not taken. To account for this drop, the firing rate for a continuous ramp must be increased above that required to sustain a steady state condition, as shown by the actual firing rate curve.

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Alt = Labeled Fig.7 Firing rate during ramp. Similar to the previous charts with the same lines for valves 201 and 200 marked. Above those lines is a line similar to the 6A and 6B in Fig. 6, marked Boiler master and Megawatts respectively, at the far left of the chart, but at point C of the x axis, the line diverges into 3 branches, converging again at point E. The top one is a solid line with an arrow pointing rightward, marked Actual firing rate. The middle line is made of short dashes, with an arrow pointing rightward, marked Interrupted ramp. The bottom line is made of long dashes with an arrow pointing leftward, marked Deramp, and it has a vertical dashed line dropping down from its middle to the x axis at a point preceding point D, marked X.

#BoilerManual #Ramping #Section8 #Page16

based on flue gas temperature during most of the ramp, then on actual main steam temperature after the gas temperature probes retract.

A typical plot of firing rte is shown in Figure 7. The system is allowed to stabilize from points A to B. At point B, after steady state conditions are reached, the turbine load is manually increased causing thte 201 valve to begin opening. At point C, the turbine is automated and the MW demand station increased, initiating the ramp.

Notice that from point C to the end of the ramp at point E, there are three curves for firing rate.

During a continuous ramp, the system never reaches steady state. This means there is a continuous demand for steam flow and firing rate is being increased at this time. Because the steam flow changes faster than firing rate can change, a drop would develop in steam temperature if corrective measures were not taken. To account for this drop, the firing rate for a continuous ramp must be increased above that required to sustain a steady state condition, as shown by the actual firing rate curve.

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Alt = Labeled Fig.7 Firing rate during ramp. Similar to the previous charts with the same lines for valves 201 and 200 marked. Above those lines is a line similar to the 6A and 6B in Fig. 6, marked Boiler master and Megawatts respectively, at the far left of the chart, but at point C of the x axis, the line diverges into 3 branches, converging again at point E. The top one is a solid line with an arrow pointing rightward, marked Actual firing rate. The middle line is made of short dashes, with an arrow pointing rightward, marked Interrupted ramp. The bottom line is made of long dashes with an arrow pointing leftward, marked Deramp, and it has a vertical dashed line dropping down from its middle to the x axis at a point preceding point D, marked X.

#BoilerManual #Ramping #Section8 #Page15

increased flow would drop PSH outlet temperature, so the 207 valve is driven closed a proportionate amount in an effort to maintain a constant flow and therefore temperature though the PSH. The amount of 207 valve closure is based on the ratio of 201 to 207 valve port areas. As the total 201valve port area increases, the 207 valve port area must be decreased an equal amount. The initial opening of the 201 and closing of the 207 should provide an even flow exchange. The 202 valve should not have to move significantly to maintain boiler pressure.

Between points B and C, the 201 and 207 valves should stabilize in partially open positions (the 207 valve opening will vary slightly depending on firing rate).

At point C, as the 201 valves are ramped open, the 207 will begin to close entirely. As flow to the turbine is increased, the 202 will close off gradually. Flow to the flashtank will decrease as it maintains boiler pressure. The 202 valves will close entirely with the opening of the 200 valves, taking the entire system off of the bypass.

While the 205 valve has not been shown in Figure 6C, its operation should be mentioned. The 205 valve is a non-return valve. When throttle pressure increases above flashtank pressure, shortly after point C, the 205 valve will close and all steam flow willl be through the 201 valves. Flow to the flashtank through the 202 will he distributed to the feedwater heaters, deaerator and condenser.

STEAM TEMPERATURE CONTROL DURING RAMP

So far we have discussed the bypass system valve operation and the controll of pressure and flow during the ramp. The other major area of concern is the control of steam temperatures. Steam temperature control is achieved by adjustment of the firing rate. The adjustment is

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#BoilerManual #Ramping #Section8 #Page15

increased flow would drop PSH outlet temperature, so the 207 valve is driven closed a proportionate amount in an effort to maintain a constant flow and therefore temperature though the PSH. The amount of 207 valve closure is based on the ratio of 201 to 207 valve port areas. As the total 201valve port area increases, the 207 valve port area must be decreased an equal amount. The initial opening of the 201 and closing of the 207 should provide an even flow exchange. The 202 valve should not have to move significantly to maintain boiler pressure.

Between points B and C, the 201 and 207 valves should stabilize in partially open positions (the 207 valve opening will vary slightly depending on firing rate).

At point C, as the 201 valves are ramped open, the 207 will begin to close entirely. As flow to the turbine is increased, the 202 will close off gradually. Flow to the flashtank will decrease as it maintains boiler pressure. The 202 valves will close entirely with the opening of the 200 valves, taking the entire system off of the bypass.

While the 205 valve has not been shown in Figure 6C, its operation should be mentioned. The 205 valve is a non-return valve. When throttle pressure increases above flashtank pressure, shortly after point C, the 205 valve will close and all steam flow willl be through the 201 valves. Flow to the flashtank through the 202 will he distributed to the feedwater heaters, deaerator and condenser.

STEAM TEMPERATURE CONTROL DURING RAMP

So far we have discussed the bypass system valve operation and the controll of pressure and flow during the ramp. The other major area of concern is the control of steam temperatures. Steam temperature control is achieved by adjustment of the firing rate. The adjustment is

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#BoilerManual #Ramping #Section8 #Page14

The 200 valves begin to open just before D as the 201 reaches 80% open. Since approximately 20% load can be carried by the 201 valve, the 200 valves are pulsed open to provide the additional flow requirements at point E. The pressure ramp is complete with the 200 valves open and the unit at 33% load.

Throttle pressure should not change with the initial opening of the 201 valves. A simple flow exchange takes place. Some of the flow which was initially through the 207 valve to the flashtank will be passed directly from the PSH outlet through the 201 to the turbine. Steam flow from the flashtank through the 205 valve will be reduced by the amount of flow through the 201. MW's will increase slightly, as shown in Figure 6B, to correspond to the manual increase in turbine loading.
the 201's. {sic. This is a stray from I don't know what paragraph--it just sits here in the book, orphaned. I'll take this time to note that as a rule I re-type things as I find them on any given page, but I've made exceptions when I find obvious typos or inconsistencies in punctuation, tab intents and minor grammar issues. Purists should note well that I've also scanned every page of this thing.}

During the actual pressure ramp, both throttle pressure and MW's should increase linearly to normal operating pressure and 33% load at point E. For throttle pressure, this is shown by the dotted line on Figure 6B. Actually, most of the pressure drop across the 200 valves is relieved with their initial opening, and throttle pressure will probably rise to normal levels as shown by the solid line. There may also be a slight increase in MW's above the curve shown to correspond to the increased throttle pressure.

As the 201 valves are opened, flow to the turbine is increased as flow through the boiler is maintained at 33% by the boiler feed pumps. To compensate for the increased flow through the 201's, flow to the flashtank must be reduced. This is accomplished by closing the 207 and 202 valves as shown in Figure 6C.

At the time the SSH pressure ramp is started, the 207 valve opening is programmed off of PSH outlet temperature. With the initial opening of the 201 valves at point B, flow through the PSH will try to increase. An

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#BoilerManual #Ramping #Section8 #Page14

The 200 valves begin to open just before D as the 201 reaches 80% open. Since approximately 20% load can be carried by the 201 valve, the 200 valves are pulsed open to provide the additional flow requirements at point E. The pressure ramp is complete with the 200 valves open and the unit at 33% load.

Throttle pressure should not change with the initial opening of the 201 valves. A simple flow exchange takes place. Some of the flow which was initially through the 207 valve to the flashtank will be passed directly from the PSH outlet through the 201 to the turbine. Steam flow from the flashtank through the 205 valve will be reduced by the amount of flow through the 201. MW's will increase slightly, as shown in Figure 6B, to correspond to the manual increase in turbine loading.
the 201's. {sic. This is a stray from I don't know what paragraph--it just sits here in the book, orphaned. I'll take this time to note that as a rule I re-type things as I find them on any given page, but I've made exceptions when I find obvious typos or inconsistencies in punctuation, tab intents and minor grammar issues. Purists should note well that I've also scanned every page of this thing.}

During the actual pressure ramp, both throttle pressure and MW's should increase linearly to normal operating pressure and 33% load at point E. For throttle pressure, this is shown by the dotted line on Figure 6B. Actually, most of the pressure drop across the 200 valves is relieved with their initial opening, and throttle pressure will probably rise to normal levels as shown by the solid line. There may also be a slight increase in MW's above the curve shown to correspond to the increased throttle pressure.

As the 201 valves are opened, flow to the turbine is increased as flow through the boiler is maintained at 33% by the boiler feed pumps. To compensate for the increased flow through the 201's, flow to the flashtank must be reduced. This is accomplished by closing the 207 and 202 valves as shown in Figure 6C.

At the time the SSH pressure ramp is started, the 207 valve opening is programmed off of PSH outlet temperature. With the initial opening of the 201 valves at point B, flow through the PSH will try to increase. An

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#BoilerManual #Ramping #Section8 #Page13

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Alt = Labeled Fig. 6 The ramping process. The image incorporates 3 different charts, one above the other, marked in top down order, 6A, 6B and 6C. The x axis on all 3 is labeled Time, but none of them is marked out in terms of the clock; they're marked out in terms of sequence of events marked at points A, B, C, D and E. A, B and C are situated to the left of the midsection, and D & E are marked to the right of the midsection.

The y axis on all 3 are in terms of percent, but the middle chart, 6B, is marked Percent and pressure. The lines on the 6A chart, in top down order, are Boiler master, 201 (left end is marked Closed and the right end is marked 100% open) and 200 - pulsed open (a short diagonal line between a bit before point D on the x axis where it's marked Closed, and the other end intersecting with the 201 line where it's 100% open). The line depicting the 201 is the same on all 3 graphs. So is the 201 line. The Boiler master line has 4% marked on its left end, then steps up to 6.5%, then slants upward where, at point E, it's marked as 33%.

Chart 6B has 2 lines above the lines for the 201 and the 200--in top down order, marked Throttle pressure and Megawatts; the Megawatts line looks identical to the Boiler master line in Chart 6A but doesn't have the 4% place marked as such. The Throttle pressure line is marked 500 psi along its left end, increases a little after point C, then shows that it more-or-less achieves Normal operating pressure just before point D.

Chart 6C is all valves, with the standard lines for the 201 and 200 put in. 202 and 207 were added and it simply illustrates what the main text describes.

#BoilerManual #Ramping #Section8 #Page13

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Alt = Labeled Fig. 6 The ramping process. The image incorporates 3 different charts, one above the other, marked in top down order, 6A, 6B and 6C. The x axis on all 3 is labeled Time, but none of them is marked out in terms of the clock; they're marked out in terms of sequence of events marked at points A, B, C, D and E. A, B and C are situated to the left of the midsection, and D & E are marked to the right of the midsection.

The y axis on all 3 are in terms of percent, but the middle chart, 6B, is marked Percent and pressure. The lines on the 6A chart, in top down order, are Boiler master, 201 (left end is marked Closed and the right end is marked 100% open) and 200 - pulsed open (a short diagonal line between a bit before point D on the x axis where it's marked Closed, and the other end intersecting with the 201 line where it's 100% open). The line depicting the 201 is the same on all 3 graphs. So is the 201 line. The Boiler master line has 4% marked on its left end, then steps up to 6.5%, then slants upward where, at point E, it's marked as 33%.

Chart 6B has 2 lines above the lines for the 201 and the 200--in top down order, marked Throttle pressure and Megawatts; the Megawatts line looks identical to the Boiler master line in Chart 6A but doesn't have the 4% place marked as such. The Throttle pressure line is marked 500 psi along its left end, increases a little after point C, then shows that it more-or-less achieves Normal operating pressure just before point D.

Chart 6C is all valves, with the standard lines for the 201 and 200 put in. 202 and 207 were added and it simply illustrates what the main text describes.

#BoilerManual #Ramping #Section8 #Page12

The boiler master is increased at a constant rate set by the operator at the MW demand station. Throttle pressure should increase linearly with time, as should MW's, as the 201 valves are opened.

Initially, we will plot the boiler master position relative to 201 valve demand, as shown in Figure 6A, then reference the rest of our curves to 201 and 200 valve actions. Point A is the initial condition just prior to opening the 201 valves. When all of the pre-ramp conditions are satisfied the boiler control should be placed on automatic to the MW demand station between points A and B.

At point B, the turbine is manually increased to 6.5% of full load. The boiler follows with a slight increase in the boiler master signal and the 201 valves open to their initial position. The time between points B and C is a stabilization period allowing the system time to settle out after the introduction of flow through the 201's. If the pre-ramp conditions are correct the system will see very little change and the period between B and C will be short.

When the system has stabilized at point C, the turbine is automated and the MW demand station increased to 33% of its full load value. This initiates th actual pressure ramp, and linearly increases the boiler master from point C to E.

The 201 valves are opened from their initial value at point C to their full open position at point D. The demand for the 201 valve is non-linear as shown in Figure 6A, with the demand signal increasing faster toward the end of the ramp than it does early in the procedure. This provides good flow characteristics by causing the actual flow through the 201's to be nearly linear.

------------------------------------------------- 12 ------------------------------------------------------

#BoilerManual #Ramping #Section8 #Page12

The boiler master is increased at a constant rate set by the operator at the MW demand station. Throttle pressure should increase linearly with time, as should MW's, as the 201 valves are opened.

Initially, we will plot the boiler master position relative to 201 valve demand, as shown in Figure 6A, then reference the rest of our curves to 201 and 200 valve actions. Point A is the initial condition just prior to opening the 201 valves. When all of the pre-ramp conditions are satisfied the boiler control should be placed on automatic to the MW demand station between points A and B.

At point B, the turbine is manually increased to 6.5% of full load. The boiler follows with a slight increase in the boiler master signal and the 201 valves open to their initial position. The time between points B and C is a stabilization period allowing the system time to settle out after the introduction of flow through the 201's. If the pre-ramp conditions are correct the system will see very little change and the period between B and C will be short.

When the system has stabilized at point C, the turbine is automated and the MW demand station increased to 33% of its full load value. This initiates th actual pressure ramp, and linearly increases the boiler master from point C to E.

The 201 valves are opened from their initial value at point C to their full open position at point D. The demand for the 201 valve is non-linear as shown in Figure 6A, with the demand signal increasing faster toward the end of the ramp than it does early in the procedure. This provides good flow characteristics by causing the actual flow through the 201's to be nearly linear.

------------------------------------------------- 12 ------------------------------------------------------

#BoilerManual #Ramping #Section8 #Page11

9. Set the MW demand station rate of change and increse the station to its final end of ramp position. When the MW demand station is raised, thte ramp will begin. The 201's will be gradually opened to provide a linear increase in throttle pressure. Turbine first-stage pressure increases with throttle pressure and fuel flow is increased to maintain steam temperature.

The following will take place while the unit is ramping:

A. The 201 valves will start opening to pressurize the SSH above 500 psig {Pounds per Square Inch Gauge}

B. When SSH pressure exceeds the flashtank pressure, the 205 valve will close and be interlocked closed.

C. As the 201 valves open, the 207 valve will start closing to maintain the required flow through the PSH.

D. Excess boiler flow continues to be diverted to the flashtank through the 202 valve which is controlling boiler pressure.

E. When the superheater pressure reaches 2000 psi, the 201 valve is wide open. The 200s will start pulsing open to complete pressurization of the SSH.

F. The 202 valve will fully close.

G. Turbine load will increase as pressure and flow increase.

STARTUP VALVES DURING RAMP

To fully understand what happens during the ramp, we will discuss the graphs of several parameters as a function of startup time.

------------------------------------------------- 11 ------------------------------------------------------

#BoilerManual #Ramping #Section8 #Page11

9. Set the MW demand station rate of change and increse the station to its final end of ramp position. When the MW demand station is raised, thte ramp will begin. The 201's will be gradually opened to provide a linear increase in throttle pressure. Turbine first-stage pressure increases with throttle pressure and fuel flow is increased to maintain steam temperature.

The following will take place while the unit is ramping:

A. The 201 valves will start opening to pressurize the SSH above 500 psig {Pounds per Square Inch Gauge}

B. When SSH pressure exceeds the flashtank pressure, the 205 valve will close and be interlocked closed.

C. As the 201 valves open, the 207 valve will start closing to maintain the required flow through the PSH.

D. Excess boiler flow continues to be diverted to the flashtank through the 202 valve which is controlling boiler pressure.

E. When the superheater pressure reaches 2000 psi, the 201 valve is wide open. The 200s will start pulsing open to complete pressurization of the SSH.

F. The 202 valve will fully close.

G. Turbine load will increase as pressure and flow increase.

STARTUP VALVES DURING RAMP

To fully understand what happens during the ramp, we will discuss the graphs of several parameters as a function of startup time.

------------------------------------------------- 11 ------------------------------------------------------

#BoilerManual #Ramping #Section8 #Page10

taken to automate the control system to the point where the 201 valves are opened.

RAMPING PROCEDURE

1. Align firing rate master to the measured variable and transfer to automatic.

2. With the steam temperature master aligned, transfer to automatic.

3. Align boiler master and transfer to automatic.

4. Have the high pressure superheater stop valves, 200, ready for operation with the breakers in.

5. Place the 201 pressure reducing valves in automatic.

6. Unit is now ready to ramp. Have a second polishing demineralizer ready for service.

7. Manually increase boiler load on the turbine slightly above 10% of full load flow. The boiler will follow the turbine and the 201 valves will open to their initial position.

Some transient conditions may develop with the initial opening of the 201 valves. These should be allowed to settle out. All burners which are required to complete the ramp should either be in service or ready for immediate firing. Gas temperature, PSH temperature, CP outlet temperature, and SSH outlet temperature should be stable.

It is extremely important that the 202 and 207 valve positions can be allowed to stabilize. When those conditions are met, the ramp can be initiated.

8. The turbine-generator control should be automated to the megawatt demand station.

------------------------------------------------- 10 ------------------------------------------------------

#BoilerManual #Ramping #Section8 #Page10

taken to automate the control system to the point where the 201 valves are opened.

RAMPING PROCEDURE

1. Align firing rate master to the measured variable and transfer to automatic.

2. With the steam temperature master aligned, transfer to automatic.

3. Align boiler master and transfer to automatic.

4. Have the high pressure superheater stop valves, 200, ready for operation with the breakers in.

5. Place the 201 pressure reducing valves in automatic.

6. Unit is now ready to ramp. Have a second polishing demineralizer ready for service.

7. Manually increase boiler load on the turbine slightly above 10% of full load flow. The boiler will follow the turbine and the 201 valves will open to their initial position.

Some transient conditions may develop with the initial opening of the 201 valves. These should be allowed to settle out. All burners which are required to complete the ramp should either be in service or ready for immediate firing. Gas temperature, PSH temperature, CP outlet temperature, and SSH outlet temperature should be stable.

It is extremely important that the 202 and 207 valve positions can be allowed to stabilize. When those conditions are met, the ramp can be initiated.

8. The turbine-generator control should be automated to the megawatt demand station.

------------------------------------------------- 10 ------------------------------------------------------

#BoilerManual #Ramping #Section8 #Page9

* 207 valve - in automatic with a setpoint of 700 F.

* 220 valve - in automatic and partially open.

* 240 valve - in automatic.

* 200 valves - prepared for operation.

* All other startup system valves should be in automatic controlling flashtank functions.

* Thermoprobes - in automatic.

* Gas temperature - as indicated by the thermoprobe, should not exceed 1000 F. 1000 F is the maximum allowable temperature below 10% of full load steam flow for SSH metal protection.

The emphasis at this point should be on obtaining the correct values of the temperatures listed and insuring that they have stabilized. This will minimize the amount of unnecessary changes that are introduced to the control system. A large percentage of the problems which can be encountered in the ramping process are the direct result of starting out at improper values, often because the system was still in a state of change when the ramp was initiated.

It is particularly important that bothe PSH and CP outlet temperatures be at their proper values and stabilized. With the i nitial opening of the 201 valves, steam from the PSH will be mixed with steam from the flashtank. By maintaining 700 F at the PSH outlet, the enthalpy of the steam resulting from the mixture of the two sources will not be changed.

Convection pass outlet temperature is also important as ai indication that sufficient heat is stored in the boiler to begin the ramp. Along with gas temperature, it should be used as the main indication that firing rate is correct (PSH outlet temperature will not provide this indication since it is controlled by the 207 valve). With the system stabilized, steps can be

-------------------------------------------------- 9 ------------------------------------------------------

#BoilerManual #Ramping #Section8 #Page9

* 207 valve - in automatic with a setpoint of 700 F.

* 220 valve - in automatic and partially open.

* 240 valve - in automatic.

* 200 valves - prepared for operation.

* All other startup system valves should be in automatic controlling flashtank functions.

* Thermoprobes - in automatic.

* Gas temperature - as indicated by the thermoprobe, should not exceed 1000 F. 1000 F is the maximum allowable temperature below 10% of full load steam flow for SSH metal protection.

The emphasis at this point should be on obtaining the correct values of the temperatures listed and insuring that they have stabilized. This will minimize the amount of unnecessary changes that are introduced to the control system. A large percentage of the problems which can be encountered in the ramping process are the direct result of starting out at improper values, often because the system was still in a state of change when the ramp was initiated.

It is particularly important that bothe PSH and CP outlet temperatures be at their proper values and stabilized. With the i nitial opening of the 201 valves, steam from the PSH will be mixed with steam from the flashtank. By maintaining 700 F at the PSH outlet, the enthalpy of the steam resulting from the mixture of the two sources will not be changed.

Convection pass outlet temperature is also important as ai indication that sufficient heat is stored in the boiler to begin the ramp. Along with gas temperature, it should be used as the main indication that firing rate is correct (PSH outlet temperature will not provide this indication since it is controlled by the 207 valve). With the system stabilized, steps can be

-------------------------------------------------- 9 ------------------------------------------------------

#BoilerManual #Ramping #Section8 #Page8

The pressure ramp is an extremely complicated procedure. It relies on the proper operation of numerous valves ond on maintaining the proper firing rate for each steam flow. Steam flow to the turbine is increased to 33% in a relatively short period of time and there is little room for error.

PRE-RAMP CONDITIONS

For the pressure ramp to work properly, it is extremely important that a definite and precise procedure be developed and strictly adhered to for each and every ramp. Conditions prior to initiating the ramp must be the same every time. This point is essential to the success of the ramp and cannot be over-emphasized.

To aid in obtaining stable and consistent pre-ramp conditions, the following guidelines should be observed by the operator immediately prior to initiating each ramp:

* Boiler feed pump - in automatic.

* Feedwater flow - 33% of full load flow (1,400,800 lb/hr).

* Condensate regulator - in automatic.

* Make-up regulator - in automatic.

* Superheater spray valves - reset.

* Primary superheater outlet - fluid temperature should be stable at 700 F.

* Flashtank - should be at 500 psi.

* The turbine valves should be on partial arc and in manual. They should be just below the point where the 201 valves will be opened.

* Bypass system - mode selector switch in startup.

* 202 valve - in automatic.

-------------------------------------------------- 8 ------------------------------------------------------

#BoilerManual #Ramping #Section8 #Page8

The pressure ramp is an extremely complicated procedure. It relies on the proper operation of numerous valves ond on maintaining the proper firing rate for each steam flow. Steam flow to the turbine is increased to 33% in a relatively short period of time and there is little room for error.

PRE-RAMP CONDITIONS

For the pressure ramp to work properly, it is extremely important that a definite and precise procedure be developed and strictly adhered to for each and every ramp. Conditions prior to initiating the ramp must be the same every time. This point is essential to the success of the ramp and cannot be over-emphasized.

To aid in obtaining stable and consistent pre-ramp conditions, the following guidelines should be observed by the operator immediately prior to initiating each ramp:

* Boiler feed pump - in automatic.

* Feedwater flow - 33% of full load flow (1,400,800 lb/hr).

* Condensate regulator - in automatic.

* Make-up regulator - in automatic.

* Superheater spray valves - reset.

* Primary superheater outlet - fluid temperature should be stable at 700 F.

* Flashtank - should be at 500 psi.

* The turbine valves should be on partial arc and in manual. They should be just below the point where the 201 valves will be opened.

* Bypass system - mode selector switch in startup.

* 202 valve - in automatic.

-------------------------------------------------- 8 ------------------------------------------------------

#BoilerManual #Ramping #Section8 #Page7

-------------------------------------------------- 7 ------------------------------------------------------
Alt = Labeled Fig. 5 Ramping -- Normal operation at minimum load. Image is just like the others, sideways with the bottom long the right edge and the top along the left edge, with the focus on the superheaters et al but when the system is operating normally with minimum load conditions. Please refer to the main text for details.

#BoilerManual #Ramping #Section8 #Page7

-------------------------------------------------- 7 ------------------------------------------------------
Alt = Labeled Fig. 5 Ramping -- Normal operation at minimum load. Image is just like the others, sideways with the bottom long the right edge and the top along the left edge, with the focus on the superheaters et al but when the system is operating normally with minimum load conditions. Please refer to the main text for details.

#BoilerManual #Ramping #Section8 #Page6

-------------------------------------------------- 6 ------------------------------------------------------
Alt = Labeled Fig. 4 Ramping -- Completing superheater pressurization. Image is just like the others, sideways with the bottom long the right edge and the top along the left edge, but with the focus on the superheaters et al. Please refer to the main text for details.

#BoilerManual #Ramping #Section8 #Page6

-------------------------------------------------- 6 ------------------------------------------------------
Alt = Labeled Fig. 4 Ramping -- Completing superheater pressurization. Image is just like the others, sideways with the bottom long the right edge and the top along the left edge, but with the focus on the superheaters et al. Please refer to the main text for details.

#BoilerManual #Ramping #Section8 #Page5

-------------------------------------------------- 5 ------------------------------------------------------
Alt = Labeled Fig. 3 Ramping -- Pressurizing superheater Image is just like the one before this one, sideways with the bottom long the right edge and the top along the left edge, but with the focus on the relationship between the superheaters and the flashtank. Please refer to the main text for details.

#BoilerManual #Ramping #Section8 #Page5

-------------------------------------------------- 5 ------------------------------------------------------
Alt = Labeled Fig. 3 Ramping -- Pressurizing superheater Image is just like the one before this one, sideways with the bottom long the right edge and the top along the left edge, but with the focus on the relationship between the superheaters and the flashtank. Please refer to the main text for details.

#BoilerManual #Ramping #Section8 #Page4

-------------------------------------------------- 4 ------------------------------------------------------
Alt = Fig. 2 Ramping -- Opening of 201 valves. Image is just like the one before this one, sideways with the bottom long the right edge and the top along the left edge, but with the focus on the 201 set of valve {there's only one in the drawing.You'd have to go all the way back to the previous section, page 2, to discover that there exists, in series, a 201A valve next to the 201}, following the details laid out in the main text.

#BoilerManual #Ramping #Section8 #Page4

-------------------------------------------------- 4 ------------------------------------------------------
Alt = Fig. 2 Ramping -- Opening of 201 valves. Image is just like the one before this one, sideways with the bottom long the right edge and the top along the left edge, but with the focus on the 201 set of valve {there's only one in the drawing.You'd have to go all the way back to the previous section, page 2, to discover that there exists, in series, a 201A valve next to the 201}, following the details laid out in the main text.

#BoilerManual #Ramping #Section8 #Page3

At this point the most critical step in the startup of a UP boiler begins (Figure 2). When the above conditions are reached the 201 valves are opened slightly. The 207 valve closes a proportional amount in order to maintain a constant temperature through the PSH and some flow is passed directly from the PSH to the SSH for the first time. Total steam flow to the turbine is unchanged. Flow is now divided between the 201 valves and the 205 valve via the flashtank, as opposed to all flow through the 205 valve before the 201's were opened. The bypass system continues to distribute the remaining flow to the feedwater heaters, deaerator and condenser.

The 201 valves are opened based on load demand and will increase pressure in the SSH and flow to the turbine. As flow to the turbine is increased, flow to the flashtank is reduced. When the SSH pressure exceeds the flashtank pressure the 205 non-return valve will close (Figure 3). All flow to the turbine is directly through the 201's . As the 201 valves open, the 207 valve is driven closed and the 202 begins closing to maintain boiler pressure. When superheater pressure reaches approximately 2000 psig, the 201 valve is wide open. To complete the pressurization of the superheater the 200 valves are pulsed open to pass full minimum flow through the SSH to the turbine (Figures 4 and 5). The 202 valves will then close completely, taking the system off the bypass.

This gradual pressurization of the SSH from 500 psi to normal operating pressure and increase of generator output from 6.5 to 33% load is referred to as the SSH pressure ramp. The system is designed to provide a fully automatic ramp. The system is designed to provide a fully automatic ramp. The opening of the 201 and 200 valves are preprogrammed based entirely on the megawatt (MW) load demand. Final load and the rate of load change are set by the operator at the MW demand station. Firing is automatically increased to maintain steam temperature as the flow is increased through the superheaters. During the ramp, control of the firing rate is based on gas temperature as measured by the thermoprobes. When minimum load is reached, firing rate control is based on the actual steam temperature.

-------------------------------------------------- 3 ------------------------------------------------------

#BoilerManual #Ramping #Section8 #Page3

At this point the most critical step in the startup of a UP boiler begins (Figure 2). When the above conditions are reached the 201 valves are opened slightly. The 207 valve closes a proportional amount in order to maintain a constant temperature through the PSH and some flow is passed directly from the PSH to the SSH for the first time. Total steam flow to the turbine is unchanged. Flow is now divided between the 201 valves and the 205 valve via the flashtank, as opposed to all flow through the 205 valve before the 201's were opened. The bypass system continues to distribute the remaining flow to the feedwater heaters, deaerator and condenser.

The 201 valves are opened based on load demand and will increase pressure in the SSH and flow to the turbine. As flow to the turbine is increased, flow to the flashtank is reduced. When the SSH pressure exceeds the flashtank pressure the 205 non-return valve will close (Figure 3). All flow to the turbine is directly through the 201's . As the 201 valves open, the 207 valve is driven closed and the 202 begins closing to maintain boiler pressure. When superheater pressure reaches approximately 2000 psig, the 201 valve is wide open. To complete the pressurization of the superheater the 200 valves are pulsed open to pass full minimum flow through the SSH to the turbine (Figures 4 and 5). The 202 valves will then close completely, taking the system off the bypass.

This gradual pressurization of the SSH from 500 psi to normal operating pressure and increase of generator output from 6.5 to 33% load is referred to as the SSH pressure ramp. The system is designed to provide a fully automatic ramp. The system is designed to provide a fully automatic ramp. The opening of the 201 and 200 valves are preprogrammed based entirely on the megawatt (MW) load demand. Final load and the rate of load change are set by the operator at the MW demand station. Firing is automatically increased to maintain steam temperature as the flow is increased through the superheaters. During the ramp, control of the firing rate is based on gas temperature as measured by the thermoprobes. When minimum load is reached, firing rate control is based on the actual steam temperature.

-------------------------------------------------- 3 ------------------------------------------------------

#BoilerManual #Ramping #Section8 #Page2

-------------------------------------------------- 2 ------------------------------------------------------
Alt = Labeled Fig. 1 Ramping -- Turbine rolling and loading. Image is just like the Figs.4A-F, sideways with the bottom long the right edge and the top along the left edge, but I color-coded the flow paths in sequence. At the lower left I have the numbers 1, 2, 3 in a column written in the colors I used for which was what order in the sequence. 1 is black; 2 is orange; 3 is purple. I have marked the connections from the PSH thru the Convection Pass, Furnace, Economizer and components connected to the two pumps (Boiler Feed and Condensate), but I didn't write that into the key.

The orange bit connects the middle port of the flashtank thru the SSH to the turbine with a dashed line and at the triangle representing the turbine is marked 4 - 6.5% steam flow, which I put in an orange box, but colored around the 6.5% in purple, marking that as partial arc level. There is an orange box around the 500 psi marking at the SSH. The purple bits connect components to the flashtank. Please see the main text for details.

#BoilerManual #Ramping #Section8 #Page2

-------------------------------------------------- 2 ------------------------------------------------------
Alt = Labeled Fig. 1 Ramping -- Turbine rolling and loading. Image is just like the Figs.4A-F, sideways with the bottom long the right edge and the top along the left edge, but I color-coded the flow paths in sequence. At the lower left I have the numbers 1, 2, 3 in a column written in the colors I used for which was what order in the sequence. 1 is black; 2 is orange; 3 is purple. I have marked the connections from the PSH thru the Convection Pass, Furnace, Economizer and components connected to the two pumps (Boiler Feed and Condensate), but I didn't write that into the key.

The orange bit connects the middle port of the flashtank thru the SSH to the turbine with a dashed line and at the triangle representing the turbine is marked 4 - 6.5% steam flow, which I put in an orange box, but colored around the 6.5% in purple, marking that as partial arc level. There is an orange box around the 500 psi marking at the SSH. The purple bits connect components to the flashtank. Please see the main text for details.

#BoilerManual #Ramping #Section8 #Page1

Ramping

INTRODUCTION

The Bypass section of this manual described the sequence of events that occur in the
early stages of startup and touched briefly on the secondary superheater (SSH) pressure ramp. Due to the importance of the pressure ramp it is dealt with in more detail in the following pages.

THE PROCESS

With the UP boiler, a minimum design flow equal to 33% of full load flow must be circulated through the furnace and convection pass enclosure circuits whenever the unit is being fired to prevent overheating of the boiler tube metals.

Early in the startup sequence, when turbine steam requirements are less than 33% flow, all flow is routed through the bypass system where it is distributed to the turbine, deaerator, feedwater heaters and the condenser. The 202 and 207 valves will be controlling flow (33% minimum) to the flashtank, maintaining 2550 psi at the convection pass (CP) outlet and 700 F at the primary superheater (PSH) outlet (Figure 1).

The turbine is synchronized and initially loaded with 500 psi steam from the flashtank via the 205 valve. After the initial loading, turbine load is increased to 6.5% and transferred to partial arc admission. At 10% load on partial arc admission with 500 psi flashtank steam, the turbine control valves will be at the position equivalent to 33% load at full throttle pressure.

-------------------------------------------------- 1 ------------------------------------------------------

#BoilerManual #Ramping #Section8 #Page1

Ramping

INTRODUCTION

The Bypass section of this manual described the sequence of events that occur in the
early stages of startup and touched briefly on the secondary superheater (SSH) pressure ramp. Due to the importance of the pressure ramp it is dealt with in more detail in the following pages.

THE PROCESS

With the UP boiler, a minimum design flow equal to 33% of full load flow must be circulated through the furnace and convection pass enclosure circuits whenever the unit is being fired to prevent overheating of the boiler tube metals.

Early in the startup sequence, when turbine steam requirements are less than 33% flow, all flow is routed through the bypass system where it is distributed to the turbine, deaerator, feedwater heaters and the condenser. The 202 and 207 valves will be controlling flow (33% minimum) to the flashtank, maintaining 2550 psi at the convection pass (CP) outlet and 700 F at the primary superheater (PSH) outlet (Figure 1).

The turbine is synchronized and initially loaded with 500 psi steam from the flashtank via the 205 valve. After the initial loading, turbine load is increased to 6.5% and transferred to partial arc admission. At 10% load on partial arc admission with 500 psi flashtank steam, the turbine control valves will be at the position equivalent to 33% load at full throttle pressure.

-------------------------------------------------- 1 ------------------------------------------------------

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I need to consult confidentially with someone with extensive experience helping people maintain Section 8 housing eligibility in New York.
I'm looking for someone with direct knowledge of "If you do <x>, the government will do <y>" for lots of different scenarios.
I don't want to just do a Google search and call random people; I'm hoping for personal recommendations.
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#Section8 #NewYork