Lub Oil System

7/31/2019 Lub Oil System

1/20

May 24, 2012 PMI Revision 00 1


2/20


Purpose of lubrication system.

Components of lubrication system.

Lub Oil circuit

Specification of oil


3/20


Importance of the lubrication system

To reduce the wear and tear of the rotating elements.

To maintain the temperature of the bearings.


4/20


Purpose of Turbine oil system

Lubrication of turbine.

Cooling of bearings

Sealing medium in Hydrogen cooling system

Turbine barring gear operation.

Working fluid in Governing system


5/20


Main oil Pump.

Auxiliary oil pump

Emergency oil pump

Jack oil pump

Main Oil Tank


6/20


Oil coolers

Oil Filters

Oil Injectors

Centrifuge

Vapour Extractors


7/20


Injector

IPT LPTHPTGen

MOP

JOP

Oil cooler

Filter

AOP

EOP

MOT

Vap. Ext


8/20



9/20


In case of AC failure ( Black out ).

EOP will startExtend the DG supply to the emergency MCCStart AOPStart JOP.

Rotate turbine with Barring gear.


10/20


Specific Gravity 0.852 @ 50 0C Kinematic Viscosity 28 cs

Flash point 2010

C (Min)Pour Point - 6.6 0C (Max)Mechanical Impurities Nil

The recommended turbine oil Servo prime-46 of IOC.


11/20


MAIN OIL PUMP(MOP)

LOCATION: This pump is mounted in the front bearingpedestal. It is coupled with turbine rotor through a gear

coupling.

Oil suction from MOT Through two number of injectors

connected in series.

Takes over when turbine speed > 2800 rpm.

Supplies oil for turbine bearing lubrication as well as for

the turbine governing system. .


12/20



13/20


AUXILIARY OIL PUMPS(AOPS)

Two in number, AC motor driven Vertical one stage rotory pump with radial impeller & spiral casing.

Supplies oil during turbo-set starting and stopping when the turbine

is running at speed lower than 2800 rpm supplies oil to governing

system as well as to the lubrication system. It also serves as standby to main centrifugal oil pump.

Submerged pump body


14/20


EMERGENCY OIL PUMP(EOP)

This is a centrifugal pump, driven by D.C. electric motor.

Vertical

Centrifugal submerged

This automatically cuts in when ever there is failure of A.C. supply

at power station and or the lub oil pressure falls below a certain

value. This pump can meet the lubrication system requirement

under the conditions mentioned above.


15/20


JACKING OIL PUMPS(JOPS)

JOP1 & JOP2 Both pumps are AC driven but in some of the plants one

of the JOP is DC driven also.

To lift the rotor assembly during TG start up and shut

down.

Suction from MOT.

delivers a pressure of 120kg/cm2 for lifting of rotor.


16/20


OIL COOLERS

To cool the lubricating oil

Consists of tube nest, inner & outer shell & water boxes

The cooling medium for these coolers is circulating water.

The pressure of the cooling water is kept lower than that of oil toavoid its mixing with oil in the event of tube rupture.

OIL TEMP. CONTROLLER for maintaining the lub oil temp atrated value by controlling the flow through the coolers.


17/20


VAPOUR EXTRACTION SYSTEM

Two Vapour Extractor fans

Exhaust fans

Maintains -ve pressure inside MOT Removes oil fumes from the MOT.


18/20


OIL Filter

Basket type filter inside the oil tank

For thrust bearing

Duplex filter Filter changeover required after choking.


19/20


Main Oil Centrifuge

Required for removing moisture from the turbine oil.

A portion of oil is continuously circulated through the centrifuge to

remove the moisture from the oil.


20/20


Documents

Lub Oil System