Main Turbine Lube Oil (MTLO)

Question 1

What is the purpose of the MTLO system?

Answer 1

provides lube oil to the main turbine and generator bearings

provides lube oil to the lift oil pumps’

supplies oil to the generator seal oil system

Question 2

what is the heat sink for the MTLO coolers?

Answer 2

TC

Question 3

What system powers the ESOP and EBOP?

Answer 3

NKN-M46

Question 4

The MTLO system is a backup oil supply for what system?

Answer 4

Generator seal oil when both the main and emergency seal oil pumps fail

Question 5

What system purifies the MTLO system?

Answer 5

OS - Lube oil storage and transfer

Question 6

What is the capacity of the LO reservoir and what is normal level?

Answer 6

Capacity of 11200 gallons
Normal level of 8550 gallons

Question 7

What is the main shaft oil pump rated for?

Answer 7

1500gpm and 235psig @ 3600rpm

Question 8

What is the motive force used to drive the booster pump?

Answer 8

Oil driven turbine where a portion of the main shaft oil pump discharge is routed to the inlet of the turbine

Question 9

What provides the motive force for the Main shaft oil pump and where is it located?

Answer 9

Gear driven from the HP turbine shaft and is located in the HP turbine housing on the 176’

Question 10

What pump is used if the booster pump output is insufficient to drive the oil driven turbine?

Answer 10

The motor suction pump will be used to supply the Main shaft oil pump suction

Question 11

What is the purpose of the motor suction pump?

Answer 11

To provide the main shaft driven oil pump with a source of oil to its suction when the turbine speed is less than 90%

The booster pump will have sufficient capacity when the turbine speed is greater than 90%

Question 12

What is the motor suction pump rated for?

Answer 12

1500 gpm @ 15psig

Question 13

What is the purpose of the turning gear oil pump?

Answer 13

To provide bearing oil to the turbine bearings while the turbine is on the turning gear or when it is coming up to speed

Question 14

What is the turning gear oil pump rated for?

Answer 14

1275gpm @ 43psig

Question 15

What signals would cause an auto start of the turning gear oil pump?

Answer 15

Main shaft oil low discharge pressure @ 190psig

Low bearing oil pressure @ 15psig

Question 16

How often is the auto start tested on the turning gear oil pump and where are the pushbuttons for the tests?

Answer 16

Weekly? (double check this)
4 buttons, 2 in the control room and 2 at the main lube oil reservoir

Question 17

What is the purpose of the emergency bearing oil pump?

Answer 17

To supply oil for shutting down the turbine should there be a low discharge pressure on the main shaft oil pump and the turning gear oil pump

Question 18

What is the emergency bearing oil pump rated for? (EBOP)

Answer 18

110gpm @ 15psig

Question 19

What would auto start the emergency bearing oil pump?

Answer 19

Low voltage on NGN-L14 (Power supply to the turning gear oil pump

low discharge pressure of the main shaft oil pump @ 180psig AND turning gear oil pump low discharge pressure @15psig

Question 20

how often is the EBOP auto start tested and where are the pushbuttons?

Answer 20

Weekly? (double check this)
2 buttons, one in the control room and 1 in the MTLO room

Question 21

What flows on the shell side of the lube oil coolers?

Answer 21

Oil Shell
TC Tube

Question 22

How is turbine cooling water flow controlled thru the cooler?

Answer 22

Automatically at the cooler outlet by the turbine cooling water control valve (TCN-TV183)

Question 23

How is the “Double handwheel” cooler inlet valve operated?

Answer 23

Lower handwheel is used to lock the valve stem into position and the upper handwheel is used to select which cooler is in service

Question 24

how can I tell if the cooler is full?

Answer 24

By opening the bypass valve and observing oil flow from a constant vent on the cooler that can be seen by lifting a hatch on the reservoir

Question 25

What is the purpose of the vapor extractor?

Answer 25

Pulls air, oil vapor, hydrogen and moisture from the MTLO reservoir thru the lube oil mist eliminator adjacent to the extractor

Question 26

How do we prevent oil vapor from leaking out past the bearing oil deflector?

Answer 26

Pressure on the pedestal side of the oil deflector is less than outside

Question 27

What is the mist eliminator comprised of?

Answer 27

5 fiberglass filters mounted in parallel inside a cylindrical cylinder

Question 28

Where is the vapor extractor located?

Answer 28

176’ of the turbine building outside

Question 29

Where do I operate the vapor extractor?

Answer 29

Handswitch located by the vapor extractor

Question 30

What is the purpose of the bearing lift oil pumps?

Answer 30

To reduce the torque requirements of the turning gear motor. Supports the shaft

Question 31

What would auto start a bearing lift oil pump?

Answer 31

High discharge pressure on the turning gear pump

Question 32

What would stop the bearing lift oil pumps?

Answer 32

low suction pressure

Electrical protection signal

Question 33

What is the interlock associated with bearings 7 and 10 and the lift pumps? what is the purpose?

Answer 33

When the following conditions are met the lift pumps for 7 and 10 will stop:
Bearing oil lift pump hand switch in control room in auto
Turning gear motor is running
Turbine rotor speed is less than 2 RPM

This prevents the turbine gear from disengaging during turbine shaft pulses

Question 34

What portions of the header supply use pipe within pipe arrangement?

Answer 34

Piping near hot turbine pipes

Question 35

What main shaft oil pump discharge pressure will trip the main turbine?

Answer 35

100psig

Question 36

what bearing header pressure would trip the main turbine?

Answer 36

below 12psig.