Main Turbine Lube Oil System Flashcards
which pump supplies the oil system during normal turbine operations?
the main shaft oil pump
What is the motive force for the main shaft oil pump?
the main turbine shaft
which pump supplies oil to the bearings of the turbine generator shaft?
main shaft oil pump
which pump normally supplies oil to the suction of the main turbine shaft oil pump?
booster oil pump located in the oil reservoir
What provides the motive force for the booster pump?
the oil driven turbine which receives force from the discharge of the main turbine shaft oil pump
pressure is reduced by the booster nozzle and baffler valves
which oil pump provides oil to the turbine while it is on the turning gear?
turning gear oil pumps
which oil pumps provides oil pressure during emergency situations or while coming up to speed?
the emergency bearing oil pumps
how many lube oil coolers are there?
2
what provides the cooling medium for the lube oil coolers?
turbine cooling water
how is rate of cooling controlled in the lube oil coolers?
water flow rate is automatically adjusted to maintain temperature.
what provides suction for the shaft oil pump until the turbine reaches 90% speed?
suction pump until the booster oil pump takes over at 90%
what controls the oil flow through or around the oil driven turbine?
two baffler valves
what controls oil flow through the oil driven turbine?
the booster nozzle baffler valve
what controls flow around the oil driven turbine?
the booster bypass baffler valve
what is the main shaft oil pump suction to be maintained at?
15 psig
what maintains the bearing header pressure at 25 psig?
bearing oil header relief valve auto adjusts
what is the power source for the emergency oil pump?
NKN-M46
what provides purification for the main lube oil and feed pump lube oil system?
centrifuge
how is oil transferred to/from the storage tanks/reservoirs
transfer pump
where is the lube oil reservoir located?
in the LO room in the 140’ of the turbine building
where is the main shaft oil pump located?
it is a gear driven pump from the HP turbine shaft. located in the HP turbine housing on the 176’ of the turbine building
what is the power source for the motor driven centrifugal suction pump used while turbine speed is increased?
NH
describe the turning gear oil pump
centrifugal with a flexible coupling
what causes the turning gear oil pump to start when the switch is auto?
when the main shaft oil pump discharge pressure is low (190 psig) or the bearing oil pressure low signal (15 psig)
what is the purpose of the emergency bearing oil pumps?
supplies for for shutting down in the event of a simultaneous low discharge pressure on the main shaft and turning gear oil pump
describe the location of the Lube Oil Coolers
vertically mounted inside the LO reservoir
U-tube design
what side of the HX is the turbine cooling water on?
tube side
How is the cooling water flow controlled?
automatically controlled at the cooler outlet by throttling the turbine cooling water control valve (TIC-32)
What is the purpose of the “double handwheel” cooler inlet valve?
one wheel selects the cooler to be placed in service (upper wheel) the other is for locking the valve stem in place (lower wheel)
Where is the vapor that is extracted with the oil in the vapor extractor directed?
to the oily waste system through a floor drain.
discharges the filtered air to atmosphere
where is the vapor extractor and oil mist eliminator located?
176’ of the turbine building
how is the vapor extractor controlled?
a local handswitch
which bearings have an interlock to stop the lift oil pumps if the control room switch is in AUTO and the turning gear motor is running.
bearing 7 and 10
describe the bearing oil headers?
high pressure oil inside the low pressure drain header
what happens to the plant in the event of a loss of the LO system?
the main turbine will trip when the main shaft oil pumps drop below 110 psig
also trips when the bearing header pressure drops below 12 psig
what must the control room do if the main turbine LO is 110F or more?
they must ensure the turning gear is in “PULL TO LOCK”
