cold startup 1

7/27/2019 Cold Startup 1

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C-1 Ensure that all works permits are cancelled and all men/material are removed. Allmanholes and peepholes are enclosed.

Ensure that

a) A.C. plant is running normal. DAS room tempt is @ 230c and humidity is 70%.

b) UPS is normal

Normal UPS parameters

Inverter voltage - 240 V AC

Amperes - 35 to 40 A

c) Data Acquisition system is available.

d) All the panels i.e. DDC/FSSS/EAST/HP/LP/ bypass system, are charged.

e) 6.6 KV/415V AC supply is normal.

f) DG set is available

g) 220 V DC/ 24 V DC supply is normal

h) Fire fighting system is normal

i) LCR I/II/III/IV supply is normal

J) Intake water supply is normal and one day reservoir level is @ 6.0 M

C-2 Ensure that GS sump level is normal (@ 290 to 290.3 MEL) Ensure that inlet gatefrom CW channel is open. Line up GS pump for OHGS tanks and ensure that GSsystem is ready start the pump. Its discharge valve will open on interlock (if not,open it manually) observe the normalized current (38AC) and discharge pressure5.0 kgl/cm2. Check that GS pump recirculation valve (CW 45/44) are enclosed.Check that GS tank over flow back to channel is established (GS overflow is locateat 0 m level in turbine house). Ensure that GS tan level indication is reset checkthat adequate GS water pressure (i.e. 3.5 to 3.8 kg/cm2) is available at all places.Observe motor winding temperature (


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C-4 Line up CW system. Ensures that CW sump level is slightly higher than the normalvalue while starting the first pump (@ 291 MEL). Open softened water make upvalves (CW 5 & CW 6). Ensure that pump discharge valve is closed. Start the pumpand the discharge valve will open @ 100 for priming the system. After the system isprimed and pressure is built up, the valve will further open to full.

Observe the normalized current (@ 155 A) and pump discharge pressure (@ 1.8kg/cm2) observe the CW inlet pressure to condenser (@ 1.60 to 1.65 kg/cm 2 ) andCW differential pressure across cond. Inlet / outlet (< 0.35 kg/cm 2 ). Watch motorwinding temperature (97%)

Check that selector switch on local panel is in remote. Check that auto selectionswitch for seal oil pump on control desk is in proper position i.e. If seal oil pump Ais running, S/S should be in position 1 and if pump B is running, it should be inposition 3 position 2 indicates that both pumps are on manual. Auto/manual


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selector switch for DC seal oil pump is by passed and pump is always on autoselection. Ensure that isolation valve on control oil line to DPR B is open. Ensurethat one of the seal oil cooler is in service from water side and cooler is primedproperly. Maintain seal oil temperature at @ 400 c.

Ensure that float valves of IOT / SOT are working normal and their by pass valvesare closed. Watch level (@ g.g.) Ensure that pump recirculation valve to SOST is

closed. Check that one of the seal oil / H2 vapor extractors is running. Coolingwater to oil separator of vapor fans should be through.

Check that filter in the seal oil system at the outlet of seal oil cooler is not clogged(which will be indicated by red optical indication on the filter).

Check the seal oil system parameters.

1. Seal oil pump discharge pressure @ 7.0 kg/cm2

2. H2 gas pressure 3.3 3.5

3. Relief oil pressure EE / TE @ 7.0

4. Seal oil pressure after filter @ 6.5

5. Seal oil pressure EE / TE @ 5.8

6. Seal oil flow EE / TE @ 32 / 45 lit / Sec.

7. SOT vacuum 300 400 mm Hg.

(NOTE: - (a) Seal oil pressure EE/TE will vary as per generator casing H2 gaspressure and diff. pressure regulator. The seal oil pressure mentioned at (5) alsoincludes the static head of @ 1.2 kg/cm2. (b) Relief oil pressure is always constant

or varies only if discharges pressure of AOP varies.

C-8 Ensure sufficient MOT level (@ + 350 mm) check the readiness of AOP- I and AOPII. Ensure that MOT basket strainers are cleaned. Check that fire protection shutoff valve is closed and solenoid is reset at turb floor and in MOT room.

Aop can be started manually from PCR or on auto through SLC ON check that subgroup control of oil system is Auto ON.

Watch Aop amperes (@ 110 A) and AOP discharge pressure (@ 7.5 kg/cm2) putSLC ON of AOP-II. Ensure availability of DC LOP by starting the pump & put itsSLC ON. Watch drop in MOT level after AOP started (@ 280 mm). Ensure that oneof the lub oil coolers is in service from oil side. Optical indication (Large red arrow)on cooler change over valve gives the direction of flow of oil indicating the cooler inservice. The small black arrow shows the stand by cooler. Do not adjust anyintermediate position of change over valve. Keep GS water inlet / outlet valvesopen for the cooler in service from oil side. Charge the cooler from water side byproperly venting it. The stand by cooler should be kept drained from water side toavoid deposits on tubes causing corrosive attacks on tubes. Check lub oil flowthrough brg. Pedestals by opening the caps on pedestal outlet pipes.

Watch lub oil temperature at cooler outlet and ensure that it maintains @ 400 - 450

c through temperature control valve, put SLC of oil temperature control ON and

its reference set point at @ 400

- 450

c observe bearing drain oil temperature (>600 c ) at local. Observe journal Babbitt metal temperature / thrust bearingtemperature (>900 c & >1100c respectively) on recorder and DAS-


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Watch MOT level regularly (@ 25 mm) and ensure that there is no suddenappreciable drop in MOT level. Ensure sufficient stock of turbine oil (at least 5barrels). Ensure that at least one centrifuge is available for service and run it atleast 8 Hrs. per day.

Ensure that no filter supervisory alarm (for thrust bearing filter) is present. If

clogged, change over the filter and clean it. Optical large red arrow shows filter inservice and black arrow shows the stand by filter.

Watch the level in dirty oil tank and ensure that high level indication is notpresent on DAS. Following drains are connected to dirty oil tank a) MOT room floordrain b) leak off drains of ESVs, IVs, CVs and LP by pass valves c) H2 vapor fanexhaust pipe drains.

Ensure that one vapor extractor fan on MOT is running and the other fan isstanding by.

Check the following parameters at local / PCR

a) Discharge pressure of AOP @ 7.2 kg/cm2

b) Oil pressure before cooler @ 5.4

c) Oil pressure after cooler @ 4.8

d) MOT level @ + 25 mm

C-9 Start jacking oil pump I on manual and put its SLC ON put ON the SLC of JOP-II(NOTE : JOP will also start if SGC of oil supply system is auto ON). Observe thenormal Current (42 A) and JOP discharge header pressure (@ 120 kg/cm 2). Checkjacking oil pressure at each bearing (The pressure gauges are located inside the

box near each brg.) normally, following readings of pressure are observed.Brg. No.-1-25 kg/cm2, B2 (50 kg/cm2 , B3 50 kg/cm2 , B4 60 kg/cm2,B5 60 kg/cm2, B6 - 60 kg/cm2.

It may be noted that there are two jacking oil lines for brg. No. 1, 2, 6,

Check the freeness of rotor by hand barring. Ensure that barring gear handle isavailable near brg. No.2 Ensure that hand barring gear pin is turned properly inposition (away from the shaft ) and is not touching the shaft.

C-10 Ensure 415 V AC supply to turning gear gate valve. Check that following permissivefor starting turning gear are satisfied a) Seal oil / H2 diff. pressure > 1.0 kg/cm2,b) Seal oil pressure TE/EE > 4.4 kg/cm2, c) H2 gas pressure > 3.3 kg/cm2, d)H2 purity > 97%, e) Liquid in gen not present. Open gate gearing valve andobserve that turb speed increases to @ 110 rpm watch drop in MOT level (@ 45mm) ensure that barring gear handle is available near bearing no. 2 put ON SLCof turning gear.

Check and note down the turbovisory parameters i.e. HP/IP overall expansionsHP/IP/LP diff. expansions, axial shift.

Observe barring gear oil pressure (@ 7.0 kg/cm2) after turning gear is ON AOP

amp. Will increase to @ 125 A from 105 A.C-11 Open hot well make up valve DM 32 / DM 35 to fill up condenser to slightly higher

than normal level (i.e. 2/3 g.g. or @ 900 mm on bar indicator in PCR) check


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discharge valve CD-2/CD-4 of CEPS are operating from PCR. Check that pneumaticvalves CD-14/ CD-19 are operative from PCR. Ensure that AOP (turbine) is alreadyrunning. This is to keep LP bypass spray valves in closed condition. Ensure the lineup for starting CEP. Select the pump for starting by keeping preselection switch inproper position 1 or 2 i.e. if pump I is to be started, keep it in position 1. WhenSLC is made ON the preselected pump will get ON the corresponding dischargevalve will open on auto. Solenoid operated vent valve on CEP discharge line will

open for 20 sec and will again close. Observe the normalized current (@ 30 A) anddischarge header pressure (22 kg/cm2). The discharge valve of stand by pump willopen when the pressure before NRV of running pump develop more than 22 kg/cm 2

check that no abnormal indication is present check thrust bearing temperature(


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pressure (60 kg/cm2) is established. Observe feed water pressure/temperaturekeep close watch on dea level and maintain it at 2300 mm. Maintain hot well levelat @ 830 mm with the help of (CD 14/ CD 19/ DM 32/35).

Observe that BFP suction flow increases by same amount as feed flow to boiler. Asthe level starts coming up in the drum, slow down the feeding rate by low loadvalve (FD-20) and when the level is at Zero on indicator stop feeding water to

boiler. Bring down scoop position such that BFP discharge pressure is (@ 60kg/cm2). Select other BFP for remote / auto operation. (NOTE : (1) boiler fill pumpis lined up for deaerator if CEP is not running. If CEP is running, boiler fill pumpneed not be used. (2) BFP can be used for boiler filling instead of fill pump asdescribed in step ( c .)

C-14 Ensure that both LOPS for air heater guide bearing and for air heater supportbearing are available. Select any one LOP for A.H. guide bearing and any one LOPfor A.H. support bearing through selector on control desk. Put sub group sequenceauto-ON. The selected LOP for guide bearing will start if the guide bearingtemperature is more than 350c. The 2nd stand by LOP will start if the guide bearingtemperature does not drop below 350c within 120 sec. both will remain off if thetemperature is less than 350c.

The selected pump for support bearing will start if the support bearing temperatureis more than 450c. The stand by LOP will pick up if temperature does not dropbelow 450c. Within 120 sec. both LOPS will remain off if the temperature is lessthan 450c.

Ensure cooling water inlet / outlet valves to cooler are open. Check & note LOPdischarge pressure ( kg/cm2). Observe guide / support bearing temperature

on DAS and ensure that they do not exceed 70

0

c. Ensure that oil defector probesare inserted properly and cooling water is established. Check the probes for oilingress in A.H. carry out soot blowing regularly. Observe through glass window forany air heater fire.

C-15 Ensure that inlet dampers of ESPA and ESP B i.e. GD 3A & GD 3B are opened.

Put air heater A/B switchgear selector switch in remote position. Initiate thestarting sequence for air heater (Say A) then following operation will take place.

1) Air heater A flue gas inlet / outlet dampers (GD 1A / GD 2A) closes.

2) Air heater A inlet / outlet sec. air damper (SAD 3A / SAD 4A) closes.3) Air heater A starts.

4) If air heater B is off its flue gas inlet / outlet dampers (GD 1B / GD 2B) andSA inlet / outlet dampers (SAD 3B / SAD 4B) closes.

5) Air heater A SA inlet damper SAD 3A opens.

6) Air heater A SA outlet damper SAD 4A opens.

7) Air heater FG outlet damper GD 2A opens.

8) Air heater A FG inlet damper GD 1A opens.

Observe the normalized current of air heater A (@ 6.0 A)Ensure that Auxiliary motor (DC Motor) is ready. Trip AC motor and check that DCmotor picks up on auto (3.5 A). Restart AC motor.


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In similar way start air heater B (only step 4 will not take place as air heater A isalready running.)

C-16 Start LDO pumps after ensuring its line up. Observe the normalized current(..A)

Adjust the pump discharge pressure to @ 15 kg/cm 2 or as per requirement. Checkthat LDO recirculation valve LO11 (located in OHP near the pump) is functioningnormal. Open isolating valve on line going to either boiler I or boiler II as per therequirement. Check that manual isolating valve on LDO line to package boiler isclosed as it is normally not required. Check that LDO pressure at firing floor beforeLO trip valve is @ 10 kg/cm2 and adjust the oil pressure by LO 11 valve. Put LO 11valve control on auto.

(NOTE: LDO pressure control valve LO 11 is operative from both the PCR-I andPCR-II. The valve accepts the command which is maximum. Hence suitable co-ordination between two PCRS is required when LDO is used)

If LDO is also to be used at CD or EF elevation, ensure that HFO inlet isolatingvalve and HFO return line isolating valves are closed. This is to avoid LDO return toHFO tank. When LDO is to be used at CD/EF elevation, oil temperature Prot. isrequired to be by passed.

C-17 Line up HFO circuit ensures proper functioning of HO-11 pressure control valvelocated in OHP near the pump. Keep the valve open and start the pump. Observenormalized current (@ 15 to 16 A). Ensure that HFO inlet isolating valve at F/F is

open and LDO interconnecting valve is closed. Ensure that isolating valve on HFOreturn line to oil tank is opened.

Open HO recirculation valve Ho 35 (Located at FF) by depressing its open pushbutton. Recirculation valve will open provided a) all nozzle valves are proved closed(i.e. AB 1 to AB 4, CD 1 to CD 4, EF 1 to EF 4) b) HO trip valve (HO 29) is provedclosed. When Ho 35 is open depress HO trip valve open PB. This will open HO tripvalve HO 29 placing HO recirculation system in service at CD / EF elevation.

Adjust the HO pressure at FF as per requirement with the help of HO 11 and put iton auto. Ensure that manually operated by pass valve of HO 11 is closed and alsomanual operated pump recirculation valve (Located in OHP near pump) is closed.

Also manually operated short recirculation valve at FF should be closed (However,it may be adjusted to get required HO pressure.

Start steam tracing if steam is available from nearly running unit. Check that oiltank heating is already in service and tank temperature is @ 500c. If nearby unit isnot running FO tank heating can be started at @ 25 to 30 kg/cm2 drum pressure.Ensure that all steam traps are in service and are functioning normal.

Watch HFO pressure watch HFO temperature which would slowly rise to 1100 /1200c watch HFO flow.

Once the FO temperature is achieved 1200c HO recirculation valve (HO 35) may beclosed from PCR, however after ensuring that its by pass line is in service. Its by

pass line is envisaged with an orifice to maintain minimum return oil flow. HOrecirculation valve (HO 35) is only required during start ups to get the requiredFO/LSHS temperature.


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C-18 Check that FD fan LOPS are ready for service. Select any one LOP A or B forservice through LOP selector. Put sub group sequence of LOP on Auto-ON Thepreselected pump will start. Observe discharge pressure (@ 12 kg/cm2) control oilpressure (@ 10kg/cm2) bearing lub oil pressure (1.2 kg/cm2). Observe that lub oilpressure low and control oil pressure low indications get reset. The stand by

pump will pick up if FD fan is ON and if control oil pressure drops below 5 kg/cm

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or running pump trips.

C-19 Verify line up for starting ID fan. Check that Air heater is running. The fan andmotor bearing temperature of selected ID fan to be run are normal. Ensure thatselector switches on switch gear is in Control Room (CR) position.

Initiate the start sequence of selected ID fan (say A) then followingoperations will take please.

a. Seal Air blower for discharge gate starts.

b. I.D. Fan inlet gate (GD5A) closes.c. I.D. Fan Outlet gate (GD7A) closes.

d. I.D. Fan A regulating inlet vane (GD6A) closes.

I.D. Fan A starts. Observe normalized current (@ 65A) then,

e. I.D. Fan A inlet gate (GD5A) opens.

f. I.D. Fan A outlet gate (GD7A) opens.

g. Operate the inlet regulating vanes to get a furnace draft of 10 mm WCL onnarrow range recorder and on desk indication.

If ID Fan B is off then,h. ID Fan B inlet gate (GD5B) closes.

i. ID Fan B inlet regulating vanes (GD4B) goes to minimum.

Observe motor / fan bearing temperature (


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Observe the normalized current (@35A) The Seal air blower for hot air shut offgates will get ON as soon as FD fan is made ON. Check that they are workingnormal.

C-21 Ensure that A.C. Scanner fan is already running. Prior to starting of FD fan, it istaking suction from atmosphere and its emergency damper is open. When FD fan is

started, emergency damper closes and the scanner fan takes suction from FD fanduct.

Ensure that stand by DC scanner fan is ready for service by taking its trial, keep itstandby. Ensure that it is not rotating in reverse direction. Watch scanner fandischarge pressure and scanner / furnace difference pressure and check that itsfilters are not choked up (


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b) Furnace draft (-5 to -10 mm WCL)

c) Wind box pressure @ 35 mm WCL and furn / WB diff. pressure @ 40 mm WCL

Check that indication air flow less than 30% is reset.

Observe pressure drops in air flow system and flue gas system on DAS. ObserveID/FD fan amperes (120 A / 45 A). Observe FD fan disch pressure, FG diff.pressure across the air heater and ensure that it is within limit.

C-24 Line up aux. steam supply line to SCAPH. Charge steam coil air preheated byadmitting aux. steam by steam supply valve (AS 323). This valve is tobe regulatedsuch that secondary air temperature of @ 800 C is achieved at inlet to air heaters.This temperature rise will also be reflected in secondary air temperature after airheater and in flue gas temperature gradually.

SCAPH can be cut off when flue gas temperature after APH is more than 1200C.

C-25 Verify the line up for boiler light upa) Ensure power supply to FSSS panel

1. + 24 V DC supply

2. 220 V DC supply

3. 110 V AC 1 supply

b) Check that drum level is normal.

c) Air flow is slightly more than 30% (and less than 40%) and the indication airflow less than 30 % trip is reset.

d) AB elevation LO nozzle valves are closed.e) AB/CD/EF elevations HO nozzle valves are closed.

f) LO/HO trip valves are closed.

g) All PA fans are off

h) All coal feeders are off

i) All hot air gates are closed.

j) All scanners show NO flame (both in fire ball and discriminating scanners)

k) No boiler trip command persists.

If all above conditions are satisfied, a yellow purge ready indicating lamp glows.Depress the purge start push button and a five minute purge timer is energized aswhite lamp being ON At the end of five minutes, the boiler trip circuit is resetprovided no boiler trip condition is present. The white purge light goes OFF andgreen purge complete light comes ON

C-26 Check that burner tilt is at horizontal position and its control is on manual. Ensurecorresponding position at local.

Put furnace probe IN and check it at local. Observe furnace temperature atfurnace exit.(Note: Normally furnace probe is not used even though facility is given)


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Check that atomizing steam to HO / LS HS burners is lined up and steam controlvalve is working. Check atomizing steam pressure before control valve (@10kg/cm2 , at local) put the atomizing steam pressure control valve (OS 27) onauto with pressure set point at @ 6.0 kg/cm2 and observe that control valve ismaintaining the pressure. Check that steam traps are in service and workingnormal.Also ensure that atomizing air i e service air is available for LDO and pressure is @

7.0 kg/cm2. Ensure that air is moist free.Check oil guns for correct tip and for proper assembly of nozzles. Check that HEAigniter spark plug is cleaned.Switch ON the EP rapping mechanism and insulator heaters and ash hopper tipheaters well in advance i.e. at least 4 hrs. in advance of boiler light up

Check that rapping cycle is normal field wise i.e.

1st field 12 raps/hr2nd field 10 raps/hr

3rd field 6 raps/hr4th field 2 raps/hr5th field 1 raps/hrEmitting electrodes 10 raps/hr

Check that tip heaters are getting ON/OFF properly to maintain hopper tiptemperature at @ 1200C

Check that rapping motors are moving in correct direction.

C-27 Select LDO at AB elevation after ensuring the following.

1) All LO nozzle valves are closed.2) All HO nozzle valves are closed.3) Atomizing air manual isolating valve is open. Steam atomizing manual isolating

valve is closed and limit switch is acted.4) The oil gun is properly positioned at firing position and oil gun engaged red

indication lamp glows.5) Local oil gun maintenance control switch is in remote position.6) Scavenge valve is closed.7) LDO manual isolating valve is open and LO trip valve is open.8) Boiler is reset.

Ensure inst. air supply to HEA igniter operation.LDO at AB elevation can be selected from the oil console insert by pressing oilselection push button.

(NOTE: LO trip valve opens only when)

a) LO pressure is adequate i.e. > 3.5 kg/cm2

b) Atomizing air pressure is normal i.e. > 3.5 kg/cm2

c) Master fuel trip not operated.d) LO nozzle valves are closed.

C-28 Light up the boiler by pressing the push button for pair start (1-3 or 2-4) on FSSSconsole AB elevation. This will initiate a 90 sec start time trial.


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1) A start command is sent to oil corner 1 (when corner 1-3 is started) or to oilcorner 2 (when 2-4 are started)

2) 15 sec. later, a start command is sent to corner 3 (or to corner 4)

The following sequence of operation is executed for each gun.a) Command is given to open air atomizing hydro motor valve.b) When air hydro motor valve is open, command is given to advance HEA igniter

and operating LO hydro motor.c) When LFO hydro motor opens around 50% command is given to operate HEA

igniter. The igniter gets command for sparking only if it is in advancedcondition, and relevant limit switch is operated and spark tip is clean.

d) For each gun, trial time is fixed as 25 Sec. from opening of oil hydro motor.e) If the safe scan for that particular corner picks up and flame ON indication

appears, the gun will sustain. The gun trips if the discriminating scanner showsno flame.

The LFO pressure goes down very fast as LFO nozzle valve starts opening. Ensurethat LFO pressure is maintained as per required (@ 6.0 kg/cm2 )By LO 11 valve on auto. Other wise, the gun will trip on low oil pressure watch

closely and maintain furnace draft and drum level whenever any heat input toboiler is changed. Check that atomizing air pressure is constant at 6.0/6.5 kg/cm2.Charge ESP fields. Initially keep the current setting low (@ 50 MA ) the fields needto be charged during oil firing to avoid chloride corrosions on emitting electrodes.

C-29 As warning up of the boiler has started the temperature of flue gas and air wouldrise gradually. Steaming would start. Water would swell and drum level would rise.Check that boiler emergency drain valves B 99 B 100 open on interlock of highdrum level to maintain level. Maintain drum level normal with the help of blowdown valves and low load feed control valve FD 20. Check that electrically assistedpressure relief valve (ERV) is in auto mode and is closed as indicated by green

lamp.Watch flame visually frequently. Flame should be bright yellow without anysmoking. If it is smoky, oil pressure may be reduced. If it is too bright and lengthyair pressure may be reduce. If the flame is pulsating with intermittent smoke,burners need cleaning to remove choke up.Observe the drafts at various points on DAS and ensure that they are normal.Watch drum metal temperature on DAS (analytical Para) and ensure that they aresteadily rising. Observe that difference between Top / bottom drum metaltemperature and ensure that it is less than 50 0C while pressurizing the boiler,recommended curve, for boiler pressurizing may be followed. This curve is mostlygoverned by even heating of furnace and limitations of drum metal temperature

difference at Top / bottom. If the temperature difference is more than 500

C, reducefiring rate. Firing rate is to be adjusted such that saturation steam temperature riseis limited to 1100C / hr and maximum flue gas temperature at furnace exit is notmore than 5400C until steam flow through super heater and reheater isestablished.

While boiler is under pressurizing stage, frequent checks should be made for boilerexpansion. Special attention should be given to the expansion of the lower part ofthe boiler relative to steam pressure compare the readings with the previousreadings during commissioning.

Watch the flue gas temperature at air heater outlet frequently. Abnormal increasein gas outlet temperature would indicate that fire has developed in air heater.Observe the air heater through its peephole (glass window) for any fire. Check the


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air heater for any oil ingress by with drawing oil detection probe, carry out airheater soot blowing every 8 hrs. interval.

Adjust the heating / steam flow rate by regulating superheat start up vent. Startup vent not only expels the air but also helps to quickly dry out the super heaters.Initially, flow through super heater is improper due to condensed water; lack ofpressure etc. and as such super heaters are likely to be overheated.

C-30 When the boiler drum pressure reaches 2 to 3 Kgcm 2, close drum vents, superheater vents. Observe saturation steam temperature at drum (@ 120 to 130 0C)and drum metal temperature (130 to 1400C). Before closing the vents, ensure thatsteam is freely coming out through the vents. Check S.H. drain line physically andensure that it is hot.At @ 5.0 kg/cm2 drum pressure throttle the super heater drains and further closeat @ 8 to 10 kg/cm2 pressure.

Charge main steam line by opening the boiler outlet by pass valves (MS 301 A/302 A) prior to this, ensure that line drains MS 202/204, MS 212/214 are open

along with their isolating valves. Throttle the start up vent to regulate steam flow.Ensure that there is no hammering in MS line. Watch MS line steam temperaturewhich should slowly rise.(MSL can be charged at 5 to 6 Kgcm2 drum pressure also)

C-31 As per recommendations of chemist arrange chemical activities i.e. boiler headerblow downs at recommended drum pressure i.e. 10 Kg/cm2, 20 Kg/cm2 as perprocedure. Fire should be killed prior to giving blow down. Reduce total air flow toavoid cooling. Light up boiler after blow down is over.

C-32 When MS line is charged and a constant feed flow through economizer is

established, (i.e. normally after 10 kg/cm2

blow down & MSL charging) closeeconomizer recirculation valve (E -12)

C-33 Increase firing rate, if necessary by inserting two more AB Elevation guns as perprocedure described in earlier paragraphs. Watch oil pressure, furnace draft anddrum level.

C-34 After 20 kg/cm2 boiler blow down is over charge APRDS from self if it is alreadycharged from nearly unit.Ensure that PRDS lined up for charging. Ensure that all the drains are wide open.Check that manually operated valves are full open. Charge pressure control loop by

crack opening the control valve AS 308 (high capacity line). Watch APRDS pressureand temperature which will gradually rise. Ensure that there is no hammering inthe system. Gradually increase the opening of valve AS 308. Once the APRDStemperature reaches 1200C, check APRDS drains for free draining and then closethe drains. Raise the pressure up to 12 to 14 kg/cm2 or as per requirement.(Maximum 16 kg/cm2) and put the pressure control valve on auto. Watch forproper auto functioning.

Select any spray line (either high capacity or low capacity) for service and chargeAPRDS spray so as to maintain temperature at @ 2200C put the spray valve onauto.

Open main boiler outlet valves (MS 301/302) on MS line to get adequate PRDSpressure regulate start up vent to adjust steam flow.Keep the other pressure and temperature control loops in APRDS ready for service.


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steam pressure when start ejector is in service. This valve may be closed whenstart ejector is out off.

Watch vacuum is improving At @ 0.04 kgcm vacuum, admit steam to turbineglands by opening gland seal supply valve (MAW 10 AA01) such that a pressure of0.01 kgcm to 0.015 kgcm is available. Put the controller on auto. The rate ofvacuum pulling will be faster now when gland sealing is established. Keep the drain

valve MAW 10.Crack open observe supply valve opening (@ 30 %)

Observe gland steam pressure at local (100 to 150 mm WCL) and gland steamtemperature

(@ 1800 C)

Observe APRDS pressure & temperature observe and note HPT/IPT/LPT/differenceexpansion, axial shift, LPT exhaust hood temperature.

Start one main ejector by opening its steam valve (AS 02 or AS 03) to speed upvacuum pulling rate. Watch steam pressure & maintain it @ 6.0 kg/cm2

When vacuum is @ 0.80 kg/cm2 cut off start ejector, first by closing air valve (SM16) and then by closing steam valve (AS 04) observe that vacuum is stable.

Note the final value of vacuum at which it stabilizes (@ 0.92 kg/cm2) and noteHPT/IPT/LPT differential expansions.

C-36 Ensure that drum pressure is @ 30 kg/cm2 and firing rate is adjusted accordingly.Check that HP by pass control oil pumps are running. It is better to start them assoon as boiler is lighted up. Check that oil pumps are working normal on auto. Thepump starts at 110 kg/cm2 oil pressure and stops at 150 kgcm2. Check that all (PT L) i.e. supply/ return/ leak off oil lines to HPBP sulzer valves are open and there

is no oil leakage in the system.

Ensure the following.a) HP BP oil tank level in normalb) ESV/IVs are closed.c) Cooling water to HP BP valve steam from CEP is opend) Isolating spray valve before BP valve is open and BD valve is closed on auto.

Ensure that it is not passing.e) All controls of HP by pass inserts are on manual mode and all valves in closed

position.f) HP BP warm up valves are in closed position.

g) Ensure power supply to HP BP panel.1) Control panel 240 V AC, 1From ACDB 1 F 24

2) Oil unit a) 415 V 3 AC from turb. MCC feeder.b) 415 V 3 AC from emergency board

Ensure the following for LP by pass system.a) All manually operated valves behind LPBP control stand are open.b) LP BP control oil pressure is @ 5.5 kg/cm2

Rotate the filters in LP BP system to keep them in healthy conditionc) All manually operated by pass valves of LP BP water injection valves

(V1/V2/V3/V4) in closed position.d) Put LP BP controller on auto and ensure that it is not faulted. Check that

Automatic control interface is on auto.


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Set the fixed set point of LP BP at @ 10 kg/cm2.

Ensure that condenser vacuum is deeper than 0.75 kg/cm2 and condenserdischarge header pressure is @ 22 kg/cm2. Open the following motorized drainsalong with their manual isolating valves.1) CRH drain after HP BP (CR 206)

2082) HRH strainers drain (HR 206)

208

3) LP BP line drain HR 230/232/233

4) LP BP warm up line drain (HR 234)

312Open HP BP warm up valves from local (as they are manually operated) and chargeHP BP for warming up. Ensure that there is no hammering in the system.After adequate warming up say for 15 min, open HP BP valves HP-I and BP-II or @5%. Set the temperature set point at @ 3200C slowly increase opening of HP BPvalves watching drum level. Observe drum pressure close start up vent completely(if not closed so for) and adjust firing to maintain drum pressure at @ 30-32kg/cm2.Set the Pr. Set point of HP BP at @ 5 kg/cm 2 less than MSL pressure and put HP BPon auto. Observe that HP by pass pressure and temperature control loops areworking normal on auto.Check LP BP valves are also working on auto to maintain HRH pressure as per setpoint watch condenser level which will rise when LP BP valves start opening.Observe water injection valves V1/V2 open to maintain the LP BP VALVES STARTOPENING. Observe water injection valves V1/V2 to maintain down streamtemperature water CEP header pressure which may drop when water injection

valves open. Observe condenser vacuum which may improve when HRH system ispressurized.Observe following parameters.1) HRH pressure which will maintain at @ 10 kg/cm2 or as per set point.2) CRH temperature after attemperation which should rise3) HRH/MS temperature should rise.To raise HRH temperature burner tilt may be taken upwards.Close economizer recirculation valve (E-12 if not closed so far.

C-37 Line up stator water system and start stator water pump on recirculation with the

help of recirculation valve and pump discharge valve, adjust stator water flow to @

30 m/hr. observe S/W conductivity (@ 1 to 2 mhos/cm) & (< 5 mhos/cm).Observe the normalized current (@ 16 to 18 A)

Check that gas trap is in service and all the three valve on inlet/outlet return line to

gas trap are open. This is also necessary to vent out air from S/W system at the

time of starting the system. Ensure that there are no gas bubbles in the gas trap.

The gas bubbles in gas trap indicate H2gas leakage in the system.

Ensure that only one S/W cooler is in service. Check that polishing unit is in service

and working normal. Ensure that other S/W pump is ready for service by taking its

trial. Put stand by pump on auto selection (i.e. local/ remote switch at local panelat 4.5 M level on remote and selector on control desk in proper position).


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Check the following parameters in the system.

1. Pump discharge pressure @ 5.5 Kg/cm2

2. S/W pressure before/ after filter @ 4.8/4.5 kg/cm2

3. S/W pressure at inlet to stator @ 3.5 kg/cm2

4. S/W pressure at outlet from stator @ 1.7 kg/cm2

5. Cooling water pressure at inlet tocooler

@ 1.2 kg/cm2

6. S/W temperature at cooler outlet 400C

7. H2 gas pressure @ 3.5 kg/cm2

Ensure that H2 gas pressure > S/w pressure inlet to stator > cooling water

pressure at inlet to cooler.

(Stator water pressure at inlet to stator is measured at @ 10.5 m level. Hence

actual pressure at inlet to stator is @ (3.5 0.5 0 3.0 kgcm).

C-38 Line up H2 cooling water system. Charge H2 coolers one by one. Keep H2 cooler

inlet pressure @ 2.5 kgcm (i.e. less than H2 gas casing pressure). Close the cooler

vents.

Ensure that one of the H2 gas dryer is in service and the other gas dryer is in

reactivation change over gas dryer regularly. Check that dryer heaters are

functioning normal & get switched off at 120 c.C-39 Feed water is being fed to the boiler bypassing HPHs through group by pass valve

FD 16/FD 17. HPHs inlet/outlet valves (FD-7, FD-8, FD-10, FD-11) are closed and

by pass valves FD 9/FD 12 are open.

HPHs group by pass protection scheme consists of the following main elements.

1. By pass inlet valve FD 16

2. Non return valve FD 17

3. Solenoid operated group by pass test valves FD 130 / FD 131

4. Chagrining valves FD 18 / FD 19

5. Vent Valve FD 132

6. Dump Valve FD 125

Now, proceed to charge HPHs from feed side as follows.

1. Close all the drain valves feed water loop lines.

2. Open feed side vent valves (FD 117/FD 118) located on HPH-6 FW outlet.

3. Open feed side inlet / outlet valves of HPHs

HPH-5 Inlet valve FD-7


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HPH-5 Outlet valve FD-8

HPH-6 Inlet valve FD-10

HPH-6 Outlet valve FD-11

(NOTE: If any of the heaters i.e. HPH-5 or HPH-6 is not to be charged, its inlet / outlet

feed valves to be kept closed and by pass valve to be opened)4. Close HPH-5 feed side by pass valves i.e. FD-9 for HPH-5 and FD-12 for HPH-6

(However, refer note in point No. 3)

5. Open shell drains for a while for HPH-5 / HPH-6 and close them subsequently. Close

watch may be kept on vacuum which may drop.

6. Ensure 24 V DC supply to heater group by pass solenoid valves FD 130 / FD 131.

Ensure that inst. Air supply to these valves is also available (FD 130 / FD 131).

Close these valves from PCR and ensure that these valves are closed at site. It will

be indicated by the plunger moved inside.

7. Ensure that manual isolating valves FD 126 / FD 127 before FD 131 and FD 128 / 129

before FD 130 are open.

8. Ensure that inlet valve FD 16 and NRV FD 17 are in de-locked condition. They can be

de-locked by manual hand wheel provided at the top of the valves FD 16/17.

9. Open vent valve FD 132 to charge the control liquid i.e. feed water in the chamber on

the top of servomotor piston in FD 16 / FD 17.

10. Close dump valve FD 125 from PCR.

11. Check that all the drip valves on HPH 5/6 are working normal and put them on auto

(DR2, DR6, DR34, DR11, and DR14)

12. Ensure that various pressure gauges and temperature gauges are available.

13. Check that float switches and gauge glasses are in service.

Float switches for HPH-6

a) Two for very high level.

b) One for high level

c) One for low level

Float switches for HPH-5

a) Three for very high level.

b) One for high level

c) One for low level


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14. Put group by pass proof. on manual selection.

15. Open charging valve FD 18/ FD 19 in initial filling line a inlet to valve FD 16.

While charging HPHs from feed side, care is to be taken to watch feed water

pressure and flow and to maintain them unchanged till charging is over (If so required, by

changing scoop position of feed pump) Warming up of HPH s from feed side has started

and will be indicated by rise in feed water temperature at various points in the system.

Watch the parameters on DAS.

16. Close the vents FD 117/118 when water comes out clearly through them.

17. Close the vents FD 132 when water comes out clearly through it.

18. When down stream pressure of FD 16 reaches 90% of up stream pressure, the group

by pass inlet valve FD 16 and group by pass NRV FD17 start opening. It is full open

when the steam is lifted fully upwards touching the open position limit switch. Red

lamp on HPH group prof. module will glow when valve opens full.19. Ensure that feed water pressure is stabilized.

20. Close charging valves FD 18/19.

Group by pass protection can be tested from PCR in the following manner. Simulate HPH

very high level conditions and following will take place.

1) HPH level very high annunciation will appear.

2) Extraction steam valves Ex 12 / Ex 13 will close (if opened) and drain valve Ex 112

/ 110 will open.

3) Group by pass solenoid valve FD 130/ FD 131 will opens.

4) Dump valve FD 125 in feed line from Gr HP to HP H-5 will open.

5) Feed water by pass valve FD 9/12 will open first and then corresponding

inlet/outlet valves will close.

6) Alternate drip valve (high level) will open full (i.e. DR 14/ DR 34).

7) DR-2 for HPH-5 closes full.

After testing is over, de-energize the solenoids manually and normalize the circuit

for recharging. During testing, watch feed flow and feed pressure which should remain

constant through out the test.

C-40 When boiler fire is killed for 20 kgcm boiler blow down, this opportunity can be

utilized for change over of LDO to FO/LSHS (however changeover can be done at

any time)

1) Change over of LDO to LSHS at CD / EF elevation.

(a) Close isolating valves on atomizing air line loop to steam line.


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(b) Close isolating valves on LDO line loop to HFO line.

(c) Open atomizing steam main isolating valve (before 0S-27)

(d) Open (0S-27) valve and maintain pressure @6.0 kgcm and put the valve on

auto

(e) Open HFO recirculation iso valve at the downstream of (Ho 35) open shortrecirculation valve as per requirement to maintain oil pressure.

(f) Maintain oil pressure as per requirement through (H0 11) valve.

(g) Put FO / LSHS temperature interlock in service (if it is by passed for LDO firing)

(h) Check that Fo / LSHS oil temperature is 110 c.

Try 1 or 2 guns at CD / EF elevations to ensure that proper changeover is carried

out2) Oil changeover at AB elevation.

(a) Take oil guns at CD or EF elevation in service if load is less than 140 MW

(b) Close LDO oil isolating valve (before hydromotor) near each corner

(c) Close air atomizing isolating valve (before hydromotor) at each corner

(d) Open HFO / Steam atomizing isolating valve at each corner

(e) Ensure FO / LSHS temp. @110c and temperature protection is in service

(f) Select LSHS / FO by depressing push button on oil selection console.

Change over is complete. Try 1 or 2 guns and confirm the change over.

C-41 Steam conditioning is in progress through HP / LP by pass system. When

temperature of MS lines. CRH and HRH lines are more than 100c, following drains

can be closed.

MS 202 / 204 / MS 212 / 214, MS 222/224

CR 206/208, HR 206/208, HR 230/232

HR 233/234 HR 311/312

Line up and prepare turbine for rolling.

1. Ensure that turbine lub oil temperature control SLC is ON and is working on auto

set the temperature set point @40 c.

2. Ensure that manually operated test valves of ESVs and extraction NRVs are open.

3. Check that electro hydraulic turbine control is ON and change over from EHC to

hydraulic governor is possible. Normally turbine is controlled by EHC.


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4. Check that TSE is not faulted and TSE disc has not attended any unreasonable

position. Check that TSE influence is ON (Located in EAST panel GJJ02)

5. Check that following valves are in closed position.

ESVs / IVs / HPCVs / IPCVs / CRHNRVs / Extraction NRVS A2 A3 A4 A5 A6.

6. Check that turbine drain valves SLC is ON and all the drains have acquired theirproper position as per the temperature criteria.

(NOTE : During cold rolling, all the drains should be wide open)

Particular Criteria Position

1) Downstream of HPCVs MAL 15/16 (Valve casing temperature Sattemperature of steam)

a) When < 20 c

b) When >50 c

Open

Closed

2) HP Casing drain MAL 22 (HP casing top or bottomtemperature

a) When < 300 c &

Gen load > 2%

b) When > 350c &

Gen load > 5 %

Open

Closed

3) Drain ahead of swing check NRV

MAL 65/66

a) If NRV Closed

b) If NRV Open

Open

Closed

4) Drain before IPCV MAL 31/32 (Valve casing temperature Sat steam temperature)

a) When < 20 %

b) When > 50 %

Open

Closed

5) Drain before IV MAL 26/27 (Valve casing temperature Sat steam temperature)

a) When < 20 %

b) When > 50 %

Open

Closed

6) Extraction line drains

(A2/A3/A4/A5)

If extraction valves closed Open

7) Drains extraction Valve

A5/A3/A2

a) Position < 5 % &

Load > 2 %

b) b) Position > 15 % &

Load > 10 %

Open

Closed

8) Drain extraction NRV (A4) Pressure across NRV

a) If< 100 mm wcl

b) If> 300 mm wcl

Open

Close

9) Drain gland steam MAL 81 Gland steam temperature

a) If > 150 cb) If < 120 c

ClosedOpen

10) Drain before gland steam control Gland steam temperature


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valve, MAW 10

(NOTE : MAW-10 is manually operated drain)

a) If < 190 c

b) If > 200 c

Open

Close

Check and note down following parameters and ensure that they are within limit.

1. (HPT middle Top HPT middle bottom)

Temperature diff< 30 c

2. (IPT front Top IPT front bottom)


3. (IPT rear Top IPT rear bottom)


Check and note down the turbovisory parameters and ensure that they are within limit.

1. HPT / IPT over all expansions

2. HTP diff expansion ( - 4 to + 5.5 mm)

3. IPT diff expansion (- 3.2 to 7.2 mm)

4. LPT diff expansion ( - 7 to + 30.0 mm)

These are trip values

Check that lub oil pressure to turbine oil bearing (i.e. after cooler) is @ 4.8 kgcm and

ensure adequate oil flow to each bearing.

(NOTE: alarm values for exp. HP E + 4.5 / -3, IP E + 6 / -2.2, LPDE + 27/-6.0)

C-42 Observe the steam parameters suitable for rolling from the various criteria given in

characteristic curves on DAS.

Following is the criteria for opening HP Stop valves (ESVS)

a) Criteria x 1Temperature before HP by pass > midwall

Temperature HP Control valve + T1

This criteria ensures that steam temperature before HBP is always more than

midwall temperature of HPCV. Otherwise warming up would not take place.

It is also necessary to ensure that main steam temperature is at least 50 c

superheat than saturation temperature at that pressure.

b) Criteria x 2Saturated main steam temperature mid wall temperature HP control valve + T2

( T2 represents the temperature diff. between 100% and 50% metal temperature


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of HPCVs.) If steam sat. Temperature is selected too high (i.e. if steam pressure is

too high) the surface metal will be heated up to sat. Steam temperature and T2

will increases. If T2 increases machine will be overstressed. It is assumed that

cold metal temperature increase up-to saturation steam temperature.

C) Criteria x 3

Main Steam temperature < Mid wall temperature

HP CV + T3

This criteria ensures that main steam temperature is not too high for warming up.

Normally, the steam parameters required for cold start up are as follows.

a) Live steam pressure @ 32 to 35 kgcm

b) S.H. Steam temperature at boiler outlet 320 c

c) Reheat steam pressure 10 kgcm

d) Reheat steam temperature 320 c

- Check that TSE margin is more than 300 c.

C-43 Once the required steam conditions are achieved and critera are fulfilled for

opening stop valves, proceed to roll the machine. Normally rolling is done through

electro hydraulic governor (EHG)

1) Starting device to be brought to 0%

2) Set speeder gear position to 100% (hydraulic governor)This ensures that turbine is reset. Check that all turbine tripping orders are

cancelled i.e.

a) Over speed trip

b) Thrust bearing temperature trip

c) Electrical trip

Note down the following governing system parameters

a) Control Oil Pressure 6.5 kgcm2 > kgcm2

b) Trip Oil Pressure 6.0 kg/cm2 > kgcm2

c) Start Oil Pressure 6.0 kg/cm2

d) Auxiliary Start Oil Pressure 6.0 kg/cm2

e) Auxiliary Trip Oil Pressure 5.5 kg/cm2

If control oil pressure is less, rotate the filters in governing and ATT circuit toincrease the oil pressure.

(NOTE: Mode of operation of plate type filters use the hard wheel to turn the filtercartridges. The sludge and the dirt removed collects at the bottom. The hand wheelshould be turned through 2-3 turns daily and sludge can be removed during shut

down)By operating the starting device to zero position, control oil is first admitted in thestart up oil circuit and auxiliary start up oil circuit. The auxiliary start up oil furtherraises and builds up trip oil pressure.


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Select TSE in ADMISSION MODE

Raise starting device to more than 42% HP stop valves (ESVs) will open. Checkthat HP stop valves OPEN indication has appeared and CLOSE indication hasdisappeared.

Raise starting device further to more than 56% IP stop valves (IVS) will open.Check that OPEN indication has appeared and close indication disappeared.

(NOTE: When starting device is raised, the control oil is allowed to drain first fromauxiliary start up oil circuit. The auxiliary start up oil pressure goes down to zero.This also indicates that turbine is reset or latched properly. Check that trip oil andauxiliary trip oil pressure does not drop. Further control oil is allowed to drain fromstart up oil circuit. Check that start up oil pressure drops to zero. Then trip oil drainproportionately to open HP stop valves and IP stop valves and are held open underthe pressure of trip oil). Note down the following parameters in governing system.

This has started the warming up of HP stop valves / IP stop valves up-to thecontrol valves. Check that SLCs of AOP I/II, DCLOP are ON confirms the normalcyof the pumps by talking trials. Check the stand by seal oil pump by taking trial andput it on auto.

The warming up is carried out till the turbine stress evaluator upper marginis more than 35. For this purpose. TSE is selected in ADMISSION MODE in whichMSV and MCV are monitored.

During warming up of HPCVs and MSVs, Observe the following

a) Wall Stress Evaluator Recorder1. Vi MSV MS Valve Pt. No. 3

2. Vm MSV MS Valve Pt. No. 4

3. Vi MCV MC Valve Pt. No. 5

4. Vm MCV MC Valve Pt. No. 6

These temperatures should rise continuously. Warming up can be concluded whenabove temperature stabilise. Normally, a period of 40 minutes is sufficient.

C-44 Before the machine is rolled, the following criteria are required to be fulfilled.a) Criteria x 4

Main steam temperature > Main steam

a) Control Oil Pressure 6.5 kgcm2

b) Trip Oil Pressure 5.5 kg/cm2

c) Start Oil Pressure 0

d) Auxiliary Start Oil Pressure 0

e) Auxiliary Trip Oil Pressure 5.5 kg/cm2


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Saturation temperature + T 4

This criteria ensures that main steam is properly super heated (i.e. @50c at least)

b) Criteria x 5

Main steam temperature before HP stop valve >midwall temperature HP shaft T5.

This criteria ensures that steam temperature is above HP shaft metal temperature(@30 c).

c) TSE Margin > 35 k

Now, turbine is ready for rolling.

- Raise starting device to > 90%

And put the tracking device on

- Put TSE selection to Turbine mode

- Set speed reference to 600 rpm. The M/o will start rolling through control valve. Observe thatM/o speed is rising steadily.

CHECK THAT:

- Turning gear gate valve closes at @ 240 rpm.

- JOP I trips at @ 540 rpm.

(If JOP II is running, it is required to be hand tripped at @ 540 rpm

- Check that turbine speed stabilises at @ 600 rpm. Allow the machine to soak at600 rpm for @ 1 hr.

Watch drum level and control it during speed raising. Watch drum pressure andincrease firing rate if required (Normally 6 to 8 LV guns are sufficient at 7 kgcm oilpressure) Maintain drum pressure at @ 35 kgcm.

Observe and note down the following parameters at 600 rpm.

a. Turbine overall and diff. expansions axial shift. All diff expansions shouldmove towards positive.

b. Absolute shaft vibrations (especially HP rear/front) and bearing pedestalvibrations.

c. Bearing metal temperature (


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Observe HPCV and IPCV position (HPCV @ 20% and IPCV just start opening)

Soaking is complete when the above parameters stabilise and TSE uppermargin is achieved @ 35 K (TSE to be selected in Turbine mode which monitors HPshaft and IP shaft). During soaking period, ensure that none of the above parameters

drop drastically. Normally, one hour soaking is sufficient.

g. Observe governing system parameters

a. Trip fluid 5.2 kg/cm

b. Control fluid 6.2 kg/cm

c. Auxiliary trip fluid 5.5 kg/cm

d. Auxiliary secondary fluid 3.8 kg/cm

e. Secondary fluid HP 2.6 kg/cm

f. Secondary fluid IP 1.7 kg/cm

Auxiliary Start up / Start up fluid zero.

C-45 Line up heaters from drip side, ensure that LP heaters are already in chargedcondition from condensate side. Check that LP heaters are properly vented. Put thefollowing drip valves on auto after ensuring that they are operative from PCR. Putthe level set point at @ 0 or slightly less as per requirement.

HEATER Valve No.

LPH-2 DR 21, DR 24

LPH-3 DR 16, DR 19

(NOTE: LPH-1 does not have any level control valve in the drip line) Check that

extraction valves Ex-9, Ex-10, Ex- 11 are in closed position and extraction line

drain valves Ex-101/102 (LPH2), Ex-103 (LHP-3), Ex-113 (LHP-1) are in open

position. (Ex-113 is manual valve)

Check that test valves of extraction NRV actuators are open & 220 V supply to NRV

solenoid is available. Check that red indication showing de energized condition of

that solenoid is persisting. The red indication shows that valves are ready to open.

The green indication shows that solenoids energized and valve can not open.

C-46 Inform GCR staff to close the isolators of generators circuit breaker with proper bus

selection. Ensure that GCB spring is in charged condition and indication to that

effect is available in PCR, Check for semaphore indications of isolators in PCR.

Check 220 KV bus voltage in PCR.

C-46 After soaking the M/C at 600 rpm, proceed to raise the speed further. Raise speed

ref. set point to 3000 rpm (or slightly more is 3040 rpm) Watch that speed is risingcontinuously and steadily at specified rate of 600 rpm/minute. Turbine critical

speeds fall in this zone only. (1545 rpm, 2126 rpm) Watch and note down absolute


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shaft vibrations of HP/IP rear / front respectively and bearing pedestal vibrations

when the m/o is passing through critical speeds. Observe that AOPI trips at @

2800 rpm. Check MOP discharge pressure (@ 9.7 kgcm ) & lub oil pr. After cooler

(@5.5 Kg/cm2)

Observe the following:

a. Turbine expansions and axial shift. Expansions should steadily increase.b. Absolute shaft vibrations (< 140 )

c. Bearing metal temperature (< 100 c)

d. Bearing drain oil temperature (< 65 c) and oil flow

e. HPT T/B, inlet HP casing temperature HP exhaust, IP T/B LP exhaust and vaccum.

LP exhaust may increase. Check that SLC for LP injection valve is ON it opens at 90 c LPexhaust. Observe governing system parameters.

a. Control fluid @ 8.5 kg/cm

b. Trip fluid @ 7.5 kg/cmc. Auxiliary trip fluid pressure @ 7.5 kg/cm

d. Auxiliary secondary fluid pr @ 3.8 kg/cm

e. Secondary fluid pr for HP @ 3.0 kg/cm

Secondary fluid pr for IP @ 2.8kg/cm

f. Prim oil pressure @ 2.3 kg/cm

Observe that temperature after lub oil cooler (@ 40 42 c) and seal oil cooler

(35-40 c) check that lub oil temperature control is working normal.

Observe seal oil/H2 diff. pr and H2 pr (1.5 kgcm and 3.5 kgcm respectively)

Watch and maintain drum level, dea. Level and hot well level during speeding up of

the turbine. Watch drum pressure and slowly allow it to rise up-to 40-45 kg/cm till

the M/C is synchronized. Watch CW inlet temperature and start CT fans (@ 4 Nos)

as per requirement. Check CW inlet temperature (> 30 c) and CW diff. pressure

across condenser (> 0.4 kg/cm) watch hot well temp. (> 420 c) watch flue gas temp. At

furnace exit till the unit is synchronized.

Check that hydraulically operated extraction swing check valves (Except A4) open

as soon as sec. oil pressure reaches @3.0 kgcm (NOTE : The mechanical design of

the valve is such that they are brought into free swinging position by means of trip

oil pressure through actuator & then opened by diff. pressure present. The valves

are actuated in proportion to secondary oil pressure)

Allow the machine to soak at 3000 rpm for @ 15 to 20 minutes.

(NOTE I: When starting device is raised to 90% all CVs start opening in proportion

to secondary oil pressure HP and IP which starts building up.

Maximum Secondary Fluid Pressure 5.0 kgcmMinimum Secondary Fluid Pressure 2.5 kgcm


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The diff between max & min pressure (2.5 kgcm) correspond to 100% valve

opening.

(NOTE II: Influence of TSE margin during rolling. The rate of rise of speed is

controlled by TSE margin is 0 to 30 c K 0 to 600 rpm/min. If the margin is more

than 30 c, the sped increases at constant rate of 600 rpm/min. The rate of

change of speed is directly proportional to TSE margin. If TSE is faulted it blocksthe further raising the speed or load any how between 600 to 3000 rpm while

raising the speed. TSE influence gets bypassed so as to cross the critical speed

smoothly.

(NOTE III: If rolling is required to be done by hydraulic governing, EHG controller

should be kept in max. position. The start up device is operated and at 56% HPCVs

start opening first followed by IPCVs. The speed is kept 600 rpm. For soaking till

TSE margin is achieved 35 k. Further speed is raised by operating start up device

to max. Position. With this the speed can be raised to 2400 rpm.Further speed is raised by speeder gear.

As the M/C is soaking at 3000 rpm, check and line up excitation system. Ensure

that following electrical supply to excitation system is ON

1) 48V DC

Source I and II from 24 V battery charger feeder No 07E/10 F respectively.

2) 220 V DC Main DCDB feeder No.01 D

3) 415 V 3 , AC supply for field flashing Turb MCC (2 KA 15 B)

4) 220 V DC for field flashing Main DCDB 2 FA @ 1A

5) 1 , 240 V AC supply from UPS

- Check that pressurizing fans for thyrister panel room are running normal.

C-49 TA Set is ready for synchronization now.

Check drum pressure (@ 40 42 kgcm). Increase firing rate if required by adding

additional guns. Watch drum level and maintain it slightly on lower side as it swells

very fast after synchronization.

Now proceed to built up voltage & synchronize the set on auto check that,

1) Load control is ON

2) Adjust load limit to suitable valve (@ 30 MW). However, it can be adjusted

as per requirement.

3) Load gradient @ 10% to 12 %

4) Load reference 20 MW

5) HP/IP trimming device ON6) AVR on auto selection

7) Field breaker selection on Remote


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Switch ON field breaker. Field flashing will get (ON automatically check the

semaphore indication of field breaker and Red indication of field flashing on

control desk. Voltage will start building up fast up-to 7 KV and then slowly up-to

15.75 KV. Observe generator field voltage and field current. Check generator

voltage phase to phase and phase to neutral.

Check that GTR cooling oil pump selection switch is on AUTO ON selection andcooling control selection switch on AUTO check that pump selection is also

normal. Check that 415V AC 3 supply (Source I/II) to GT marshalling panel is

available. Check both the isolator switches in marshalling panel are ON and

either of the two control supply switches is ON Check that Supply ON lamp on

unit transformer panel in PCR is glowing.

Select synchronizer selector switch to Check position. Observe the displayed

parameters as follows.

a) Running voltage and incoming voltage. Adjust the incoming voltage by Raise or

Lower push button to the running (grid) voltage.

b) Running frequency and incoming frequency.

Adjust the incoming frequency to running frequency (grid) through key-lock

switch . Observe that needle of sychronoscope by suitably varying the turb- speed

by speed reference. Switch ON synchroscope is rotating slowly in clock wise fast

direction. If this rotation is very fast or anticlockwise or if the needle is stationery,

then speed of the incoming machine is to be adjusted by speed reference such that

the needle is rotating Slowly in Clock wise fast direction.

When proper position of synchronizing is achieved Check synchronizing

indication appears (i.e. the needle is just approaching the mark of correct phase on

synchroscope). Synchronize the set to grid and pick up 5 to 7 MW load with the

help of speed ref. The TSE disc will switch over to load side and will start showing

upper load margin.

(NOTE: If AVR is on manual and voltage is built up on manual mode, Then to put

the excitation control on auto, Adjust the null point to zero on matching voltmeterand put the excitation control on auto).

Auto Synchronizing

1) Keep AVR on Auto

2) Keep synchronizing selector switch on Auto

3) Switch ON auto synchronizer in turbine desk. Synchronizer started andSynchronizer ON lamps will glow.

4) Speed and voltage will be matched on auto.

5) As soon as check synchronizer and auto synchronizer commands match, the setgets a synchronized and @ 5 to 7 MW load will be picked up on auto. Check thatHT cooling oil pump has picked up on auto. Switch off synchronizer selector


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switch and synchroscope on generator desk. Watch drum level and control itcarefully as it has tendency to swell. Watch and maintain drum pressure.Observe and adjust power factor @ 0-85 to 0.9 lagging. Check RMVA observerotor temp. Check HP/IP tracking device is ON. Observe generator current ineach phase. Charge the generator transformer oil cooler from water side.Observe the following parameters of GTR.

a. Winding temperature HV/LV (< 90 c)

b. Oil temperature (< 90 c)

c. Cooling water pressure to GTR before APRV @ 1.0 kgcm

d. Cooling water pressure inlet to cooler @ 0.35 kgcm

e. Oil pressure at inlet to cooler @ 0.7 kgcm

f. Diff pressure between oil / water @ 0.35 kgcm

Check that oil pressure is always more than water pressure. Take out furnace

probe and check its out position at local. Switch off its module from boiler MCC.

Close all the drains on turbine side (i.e. SLC drains) if drains are on manual orcheck that they close on auto as per temperature criteria. Check and note the

following parameters.

a) Turbine expansion and axial shift.

b) Bearing metal temperature

c) Absolute shaft and bearing pedestal vibrations.

d) HP exhaust, LP exhaust, vacuum.

e) Gen slot temperature / core temperature

Let the M/C soak at 5 to 7 MW for @ 15-20 min. or till further margin isavailable. Following are the expected parameters.

Drum Pressure 50 kg/cm

SH Steam temperature 380 C

R.H. Steam temperature 360 C

Check that CRH NRVs have opened and the indication has appeared in PCR (These

NRVs are also operated in proportion to the pressure in secondary oil circuit. The

check valve open fully when main control valves have reached a lift a 5 to 10% of

max. Turbine output. During start up, when the steam pressure upstream of checkvalves is approx 1 bar greater than the down stream and at the same time

secondary oil pressure has not built up to open the valve , the steam pressure

opens the valve & the Open position is indicated in PCR by limit switch.

Charge LP heaters I, II, III one by one by opening their respective steam

extraction valves. (Ex 9, 10, and 11). Check that line drain valves (Ex 113, 102 Ex

101/102) close on auto. Watch the drip levels in LPHS on DAS and on bar

indicators (for LPH 2/3 only) Watch LPHs levels are maintained at normal valve and

note the drip valve positions. Check the extraction steam pressure, condensate

temperature at each heater outlet. Watch drip level in gauge glass and compare it

with levels in bar indicators.


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C-50 Watch TSE upper margin for load and slowly increase the load through speed

reference. Up-till now Speed Control is active. With the help of speed ref. and

load ref. try to put Load Control in service so as to have better load control.

Up-till now, HP/LP bypass is in service. If HP bypass is on auto then valves will

close down to maintain the set drum pressure and if bypass is not on auto slowly

close the valves watching drum pressure and drum level.

LP bypass sliding set point comes into action after synchronization. This set

point is generated from the 1st stage pressure at HP blading. LP bypass valves get

closed on auto. Watch hot well level and CEP discharge pressure in header (If two

CEPs are running, one can be stopped now)

As soon as sliding set point comes into service, LPBP auto interface get off.

Put HP bypass control on auto (If it is not on auto) HP bypass sliding set point

generated from UDC will maintain pressure always 08 to 10 kgcm above MS

pressure, provided.

a) HPBP desk set point is in auto mode.

b) GCB is closed.

c) Boiler MS outlet pressure is less than superheat safety valve setting

pressure. If MS outlet pressure is more than safety valve setting, it will load

to fast opening of HPBP valves.

Desk normal set point will track to auto set point. In case of tripping of

unit, it will automatically switch over to desk set point mode and will

maintain at last valve of pressure. Set HPBP temperature setting at @ 380c (Or at least 50 c higher than CRH temperature but not more than 380

c)

(NOTE: at @ 20% of the load, load reference comes into action and now load can

be raised by load reference. Load ref active indication will appear and Speed ref.

active Indication will disappear).

Slowly raise the drum pressure to @ 70 kgcm and load to @ 35 MW firing rate to

be increased if required. Normally, following parameters can be maintained.

Drum Pr kgcm Load SH temperature LV guns.

50 15 360/370 8

60 20/22 400/410 9

70 30/35 420/430 10

Adjust burner till to maintain reheat temperature. Reheat spray may be avoided

as far as possible. Maintain load at @ 30 MW for 20 mm for soaking and observe

various parameters as per previous steps.

Observe feed flow and check that recirculation valve closes when feed flowexceeds 220 T/hr. observe H2 cold gas temperature (44c) and hot gas


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temperature, stator water temperature at inlet and outlet from generator.

Observe stator water diff pressure across the filters.

When machine is soaked at 3000 rpm. It is better to carry out ATT for protective

device to confirm their healthiners.

a) Over speed test by injection

b) Axial shift trip

c) Low vaccum (hydraulic) trip

d) Remote trip solenoid 1 and 2 Tests b.c. d, are fortnightly test and over speed

testing may be done after a hot trip once in a month

(A) Over-speed Testing :

1. Stand facing towards governing stand.

2. Press left hand side know (i.e. valve KA03) and hold it in the depressedposition.

This isolates aux. trip oil circuit from over-speed trips.

3. Open hand wheel (KA01) till test pressure goes to @ 1.6/1.8 kgcm Operation

of hand wheel moves centre valve downwards and blocks the drain. Now

control oil flows into over-speed trip.

4. Auxiliary trip oil pressure will drop to zero and striker will operate compare the

result with previous one. Any deviation will indicate defect in over speed trip.

Raise test oil pressure further to 2 kgcm.

5. As soon as aux. trip oil pressure drops to zero close the hand wheel (KA01) till

test pressure drops to zero.

6. Press knob on RHS downwards till aux. trip oil circuit pressure builds up-to

6.0 kgcm.

7. Release knob (KA03)

If when knob KA02 is released and aux. trip oil pressure collapses, than KA02

should be held in depressed position for longer time. It is necessary that aux. tripoil pressure must remain steady before KA03 is released.

C-52 As soon as the PRDS is charged and stabilized, start dea pegging by opening dea

steam pressure regulating valve CR 306. Ensure that valve As 365 is open. Open

CR 306 and start deaerating the incoming condensate water. Watch dea

temperature which should rise. Once the dea temperature exceeds @120c the

pressure starts building up. Once the pressure reaches @3.5 kgcm , put control

valve CR 306 on auto. Observe deaerator level and hot-well level. Check that

pressure control by pass valve CR 309 is in closed condition. It is a motorised

inching type valve.


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(NOTE: Variable pressure operation of deaerator has been envisaged in the

system. Under normal conditions, dea is supplied with steam from turb.,

extractions. The dea pressure varies from 3.5 ata at approx 55% load

(i.e. @ 120 MW) to 6.6 ata at 100% load. Minimum 3.5 ata is pressure is always

maintained. At load below 55% the turb extraction pressure is less than 3.5 ata,dea is provided with steam from CRH. When turb extraction is not available during

condition such as load rejection, the pressure decay rate is arrested by modulating

CPV to avoid flashing. During cold start up dea pressure is maintained at 3.5 ata

through pressure control valve (CR 306). The steam is supplied from aux PRDS by

keeping electrically operated ON/OFF control valve AS 365 open and by keeping

motorised valve CR 303 (in CRH line) closed.

When CRH pressure reaches 6 ata, switch PS 201 in CRH line opens the valve

CR 303 and dea pressure is maintained through CR 306. When load exceeds 55%(@ 120 exceeds 3.5 ata, the motorised valve Ex 301 in extraction line (A4) allows

flow of steam to dea Extraction A4 NRV also opens when diff. pressure of 300 mm

WCL is created ahead of NRV)

C-53 When load on Unit is @ 20-25 MW UAT may be taken into service. Total 4

breakers of 6.6 KV for each unit are involved in change over.

a) Unit Boards

1CA and 1CB for Unit I2CA and 2CB for Unit II

b) Station Boards

0 CA/ 0 CB for Unit I

0 CC/ 0 CD for Unit II

The unit boards are supplied by respective unit aux. transformers and

station boards are supplied by Station transformer I (for Unit I) and station

transformer No. II (for Unit II).

Total 8 panels are involved in bus change over (4 far each Unit)

BTS 1 to 4 ( For Unit I)

BTS 5 to 8 (For Unit II)

The system is provided with different selectable modes of transfer through switch

S2 .

a) Manual fast Manually through fast mode and this mode is usually used.

b) Manual slow Manually through slow mode. It will give trip command to pre-

selected auxiliaries.


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c) Momentary paralleling manually by paralleling the two supplies momentarily.

This is not used.

d) Auto Mode : The system would first select fast mode and in the event of any

problem, it will switch over to slow mode.

Charge over can be initiated manually in both direction but automatic

changeover is possible only from UAT to Station bus.

Functions of various actuators and push buttons in the panes.

Designation Legend Function

1 PB I Test Scheme Testing

2 PB II Test Rest For resetting after test operation

3 PB III Lamp Test DF failed For lamp test and if DC fails onbus transfer parameters

4 PB 4 Ready for Transfer Used for all manual change overif all conditions are of bustransfer are fulfilled

5 PB 5 Blocking Reset Used for reseting after transferfailure, conditions are removed

6 S I Switch D Control Supply DC Control supply to the closingcircuit of the bus transfer system

(S-I Switch is located in BTS-I) for Unit No. 1 and BTS-5 for Unit No.2 The aux. DC

Supply is derived from two independent DC supply sources DCDB-I and DCDB-II one of

the source is selected by selector switch S-I with three

1) DCDB-I

2) DCDB-II

3) Off

7 Selector Switch S2 For selection mode of transfer

8 Selector Switch S3 Bus transfer selector switch INposition to carry out change over

Before carrying out change over ensure the following :

1) Unit bus PT5 (ie ICA / ICB or 2 CA/CB), Station bus PTs (OCA/OCB or OCC/OCD)

and incomer PTs are racked in service position.

2) 6.6 KV breakers of Unit incomer tie breaker from station bus to unit bus

(ie on ICA/ICB or 2CA/2CB) in service position with DC supply ON


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3) AC Supply to marshalling panel of unit aux. transformer to be made available and

cooling fans are ready for service.

4) Tap position of UAT is properly selected.

Check the healthiness of all the components involved in change over by pressing

PB-I (Test). This helps in checking the operations of concerned circuit breakers for

continuity. Fictitious indications I/o breaker CB I close (Test mode and Tie breaker

CB-2 open (Test mode) will appear without actually operating the breakers. During

test following indications will appear.

a)

b)

After test, push PB-2 to reset the after test indication. Check that ready for fast

change over indication is glowing. This will be available only if.

a) Aux. D.C. supply is ON (i.e. switch S-I ON)

b) I/o breaker CB-I trip supply ON (Trip circuit supervision I/c breaker CB-I actual)

indication will be persisting.

c) Tie breaker CB-2 trip supply ON (i.e. trip circuit supervision tie breaker CB-2

actual) indication will be persisting.

d) I/c breaker and tie breaker closing supply ON (Closing circuit supervision CB-1

and tie breaker CB-2 actual) indication will be persisting.

e) Over current relay on I/c breaker and tie breaker should be reset.

Push the push button PB-4 and supply change over will take place. I/c breaker

CB-1 close actual and tie breaker CB-2 open actual indication will appear and

remain persisting.

Observe that load has actually transferred which is in dictated by the respective,

ammeters, MW meters. Check the voltage of unit boards. Check UAT oil winding

temperature. Check that cooling fans start at proper temperature.

C-54 Check that drum level control is properly working with low load line valve FD 20.

Up-to 30% load i.e. 70MW low load line may be continued. Single element drum

level control is working only. During this, FD 20 may be put on auto and level to be

controlled by scoop on manual. Line up main feed lines (i.e. FD 21 and FD 22) and

ensure that they are ready for service.

C-55 Line up preferably lower most coal cycle A or B.

Start the first seal air fan after ensuring the following


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a) Suction filter is clean and diff. pressure across filter is normal is @35 mm WCL

b) FSSS supply is OK

c) Seal air dampers to mills and feeders are open

(SLD for mills and SLD for feeder)

Start the fan and observe normal current (50A to 150A variation)

Ensure that other fans are also ready for service.

Ensure that the C/o to be started is lined up. Check that all permissives for starting

PA fan are available. The PA fan ready amber lamp will glow only when, following

permissives are fulfilled.

1) Seal air blower diff pressure is OK (> 200 mm WCL) is at least one seal air fan isrunning and seal air damper to mills is open.

2) Hot air gate closed

3) No MFR trip

4) Inlet damper PAD 5 in min. position

5) Pulveriser ignition permit (i.e. at least 3 oil guns of associated elevation arealready in service) ]

6) Cold air damper PAD2 is open more than 5%

Start PA fan and observe the normalized current (@ 22A)

Check that following permissives are available for starting the coal mill.

1. Lub oil permissive, Lub oil pressure OK will be available only when.

a) Lub oil pressure is not low (> 1.5 kgcm)

b) Oil sump level is normal (If not, pumps will not start)

c) Sump oil temperature normal (> 15)

d) Lub oil filter is clean and diff pressure across filters is less than 1.5 kgcm check that one lub oil pump is running and other is auto load.

2. Seal air blower p > 200 mm WCL is seal air fan running and seal air damper to mill is open

3. Pulveriser discharge valve (i.e. MBV) open

4. Pulveriser outlet temperature < 94 c

5. Associated PA fan ON

6. Ignition permissive is associated guns in service

7. Feeder inlet gate open (This interlock is by passed. But it is necessary to check thatfeeder inlet knife gate (at least one out of two) is open.

8. Cold air gate open

9. Trap iron hopper (i.e. Reject gate valve open. This interlock is by passed. Hence itis necessary to check it physically.

10. All burner gates open (Not included hence necessary to check at site)

11. Pulveriser / feeder start permissive


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12. No auto pulveriser unsuccessful start. (This is also by passed)

Check that feeder inlet rod gates are open and bunker level in normal. Start mill from PSSS contacts(Say 1). Watch furnace draft and drum level and maintain it carefully. Observe till normalized current(22A). Open hot air shut off gate. Check that seal air blower starts on auto or otherwise start theblower.

Now open hot air and cold air dampers and manipulate their openings in such a way that primary flow

to the mill is @ 75 T/hr.. The temperature at mill outlet gradually rises to @ 77c. Watch furnacedraft. Observe PA discharge pressure. (@700 to 750 mm WCL) and PA temperature at mill inlet(@180 to 200 c) Observe total air flow and gradually bring it down to original valve with the help ofFD fans. Watch furnace draft.

Check that fuel air damper control is on auto (If control is on manual open the associated dampermanually after 50 Sec of start of feeder to max 20%) Start raw coal feeder. Observe feeder current(8A) Raise the feeder speed as per requirement watch furnace draft and drum level and maintain itwatch mill loading and feeder loading (@ 10 to 12 A). As mill gate loaded (@ 25A) the mill temperaturestarts dropping. Maintain mill temperature @ 77 c by modulating hot / cold air damper keeping PA flowto mill constant @ 55 T/hr. Observe blower diff pressure (@ 200 t0 250 mm WCL) and maintain it.

Now, the fire ball scanners will sense the flame and will be indicated by red lamp on desk. Ensure thatflame stable. Check the scanner intensity in FSSS panel and ensure that it is > 40%.

As the coal cycle has come in service, the steam parameters (pressure/temperature) will start rising.Raise the load production-etely and allow pressure to rise to 80 kg/cm by adjusting coal feeding andreduce oil pressure suitably to conserve oil.

Watch and maintain drum level hot well level, deaerator level. Observe gradual rise in flue gastemperature, air temperature and steam temperature.

Following are expected parameters.

Drum pressure (kg/cm) Load (MW) Steam temperature (c)

80 35 420 / 430

90 40 430 / 440

100 50 440 / 450

110 70 480 / 490

Observe feed-flow and check that recirculation valve closes when feed flow exceeds 220 T/hr. Raise

the load to 40 / 45 MW watching TSE margin and maintaining drum pressure as above. Let the

machine soak for some time (@ 20 min.) at 40 / 45 MW till load margin is available.

Slowly raise the load to 70 MW in a period of 50 min. and soak the machine for @ 30 minutes. Watch

steam temperature and pressure as far as possible, SH spray and HH spray is not required.Watch furnace draft (- 3mm WCL) drum level (0 on recorder) dea level (@ 1900 mm), hot well level

(850mm). Watch DM make up on DAS and make up valve opening DM 32/35 on desk. Watch OH RM

CST, levels and maintain them. Observe gradual rise in flue gas temperature and air temperature at

different points. Watch draft ganges at various points. Observe sup & R/H metal temperature

(< 550c).

As boiler load is being raised, air flow should be adjusted proportionately with steam flow (air / steam

ration approx 1.2) Check that oxygen percentage at air heater outlet is @ 4.5% (NOTE : Approximate

air quantity required for various loads as calculated from the curve given is as follows.

Load MW up-to 80 MW Total air flow T/hr.

300 T/hr.


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90 320

100 360

120 440

130 492

140 532

150 563

160 603

170 643

180 682

190 714

200 754

210 792

C-56 Line up attempt perator circuit from S.H. and R.H. Ensure that isolating valves

before / after spray control valves are open and attemperation line drains are

closed. Check that both main / stand by lines are ready for service. Check that SH

spray block valve (S 52) and RH spray block valve (R 7) are operative from PCR.

Ensure that 220 V DC supply to RH block valve solenoid is available.

S.H. spray can be cut in and / or burner filt position can be varied. When so

required by manual control of spray valves (S67, S68 or S70 & S60, S61 or S58 for

superheat. R16 or R10 and R22 & R25 for reheater)

Observe SH atlemperation flow (L/R) when spray is given and burner tlt position

when it is varied.

Reheat temperature is controlled by tilting the burhers, thus shifting the fire ball up

or down to increase or decrease the heat transfer in reheat zone. As a back up,

spray in reheater is used. When tilt comes down (-10c) or below and reheat

temperature is still more than set point (540c) both CVs come into operation (if

on auto) to maintain the temperature. However, whenever the tilt is above.

-10 position & control is on auto, then RH spray valves remain closed on auto.Observe SH temperature before / after attemperation. Check that steam

temperature after attemperation does not drop below the saturation temperature

corresponding to drum pressure. This is to avoid the quenching of steady.

Ensure that there is no diff. between LHs / RHs steam temperature.

C-57 Gradually raise the load to @70 MW and soak the M/o for @ 20 minutes. Observe

steam parameters. Observe generator currents in all phases. Observe generator

transformer winding temperature (HV/LV) and oil temperature. Observe generatorrotor temperature.


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Proceed to put S/H and R/H spray water controls and burner tilt control on auto.

Set the desired temperature of S.H. steam with the help of set point setter.

Observe deviation in desired temperature at SH outlet. Bring deviation to zero by

raise / lower push button, and then put the system on auto. Put burner tilt and RH

spray on auto similarly.

The set points of SH and RH temperature control is to be slided up as perrequirement such that desired temperature at boiler outlet is achieved. If settler is

put on auto the sliding set points as per drum pressure / load will come in service.

C-58 Put the available next coal cycle in service (Preferably consecutive) as per the load

requirement and when the running coal feeder reaches feeding @80% i.e.

(700 rpm). When 2nd coal cycle is proven in service, equalize coal feeder feedings.

The oil guns need to be continued in service until the feeder ratting of the two

feeders exceed 50% of the maximum i.e. 600 rpm each. (NOTE : If the adjacentcoal cycle is not available for service, place coal cycle serving the next closest

elevation in service. Do not remove the oil support till two adjacent coal cycles are

in service with coal feeding on each more than 50% i.e. 600 rpm)

C-59 When coal cycle is taken in service, the steam parameters will start rising and

hence load should be increased accordingly to maintain required steam

temperature and pressure.

C-59 When load on machine stabilises at @ 85 to 90 MW, HPH-5 may be charged from

steam side and when load stabilises at 100 / 110 MW HPH-6 may be put in service.

Ensure that HPHs are already charged from feed side. Proceed to charge HPHs

from steam side as follows.

Ensure that drip valves DR-2, DR-34, DR-11 are in neutral position and air supply

for their operation is available. Check that these valves are operative from PCR.

Check that manual iso, valves before after the valves are open. Check that

motorised valves DR-36, DR-312, DR-304 are available for service and are inclosed position.

DR 2 Drip of HPH 6 to HPH 5

DR 36 By pass of DR-2

DR 14 Drip of HPH-5 to flash-box

DR 11 Drip of HPH-5 to dea.

DR 34 Drip of HPH-6 to flash box

DR 6 Drip of HPH-6 to dea.

DR 312 By pass of DR-6


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for service. Ensure that other full load line is also available. After changeover, put

the control valve and scope on auto and select diff pressure mode for auto.

(NOTE : Normally, it is better to keep valve on manual and operate it as per

requirement to get sufficient p for spray i.e. 3 element control to be used)

C-61 Load is gradually raised as per TSE margin as coal mill capacity. When the load is

@100 MW proceed to start the 2nd air cycle if only one air cycle is running.

Line up ID / FD fans to be started IF fan selector switch to be selected carefully.

This key selector switch is provided on boiler desk I

a) ID Fan selector switch

When key selector notch is vertical the

1) ID Fan B will trip (i.e. it also means ID fan A is selected to run)b) When key selector notch is vertical the

1) ID Fan A will trip (i.e. it also means ID fan B is selected to run)

Now it may please be remembered that whichever fan is started, the selector

switch should kept Trip position of that particular fan to be started.

If initially i.e. in the beginning ID fan A is started, then keep selector switch in

vertical position so that ID fan A is selected to run and ID fan B can be startedwhen ever required.

cold startup 1

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