Turbine Lube Oil

8/13/2019 Turbine Lube Oil

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PPROV L ISSU

Module 234 1

Course 234 _ Turbine and Auxiliaries ModuleNOT S R F R N S

THE TURBINE LUBRICATINGOIL SYSTEM

OBJECTIVES:After completing this module you will be able to:10.1 a Explain how the bearing inlet oil pressure is controlled whenthe oil is supplied by each the following pumps:

i Main oil pump;ii Auxiliary oil pump:iii Emergency oil pump;iv Jacking oil pumps.

b Describe the adverse consequences/operating concerns causedby the following upaets:i Lube oil pressure too low 3 :ii Jacking oil pressure too low 2 :iii LubelJacking oil pressure too high 2 .

c State four protective actions initiated by dropping bearing inletoil pressure.

d State three features used in the turl ine lube oil system to protectit g inst overpressure10.2 Describe the adverse consequences/operating concerns caused byeach the following upsets:

a Bearing inlet oil temperature too low 3 ;b Bearing inlet oil temperature too high 2 .

10.3 a For each the typical lube oil impurities listed in the table onthe next page. describe the indicated numberof:i Sources:ii Adverse consequences/operating concerns caused by itspresence in the oil;iii Means o its removal.

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~ g e s 5

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~ g e s 5 6

~ P a g e 7~ P a g e 8~ g e 9 4

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Course 234 Turbine and Auxiliaries Module 10 PPROV L ISSU REFERENCES

ges 9-11 > ges ·]2 > ges 12-13 > ges 3·]4 >

ges ]4 5 >

ges 15- 6 >

ge 6 >

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Number ofMeans ofImpurity Source Consequences remov

Ware:r 4 2 3Oxidation products 2 3 3Gases 3 3 3Abrasiveparticles 4 1 3

b) Describe two general operating pra


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APPROVAL SSU Course 234 Turbine and Auxiliaries Module 10NOTES REFERENCESLUBE OIL PRESSURE CONTROL UPSETS NDPROTECTIVE ACTIONS

Control Obj 1 1 When o l is supplied by the main oil pump the bearing inlet oil pressure iscontrolled by tbe lube oil relief valve The valve operates by spillingt surplus oil bsck to the lube oil t nk wben the oil pressure exceeds a pre-set level The same valve also provides overpressure protectionIn some stations the same valve controls the bearing inlet oil pressurewben the oil is supplied by tbe auxiliary oil pump In the other stations,this pump has its own regulator The regulator operates the same way asthe lube oil reliefvalve: when the pump discharge pressure is too high, theregulator spills the surplus oil back to the lube oil tank. Typically, the pressure setpoint of this regulator is below that of the lube oil relief valve suchthat t latter remains closed.The emergency oil pump is sized to supply bearing oil at a pressure only ahout 40-60 of its normal value. At such low pressure, the lube oilrelief valve is closed, of course. Note that under the emergency cin:umstances when this pump is used, the fact that the bearing inlet oil pres·sure is not controlled is unimportant. What really counts is that all the oilcin:ulated by t pump is supplied to the turbine generator bearings in an attempt to nutintain their inlet oil pressure at a safe level. n practice, in orderto miniIJijze chances for bearing damage the turbine would be tripped andt pump would nutintain adequate bearing lubrication and cooling to allowsafe shutdownThe jacking ifting) oil pressure at the bearing inlet is also no t con·trolled. Recall that the jacking oil pumps r positive displacement type,and for such pumps, their discharge pressure depends only on the dischargeline resistance to flow assuming that the pump and its driver are strongenough). Hence, the jacking oil pressure rises until the turbine generatorrotor is lifted enough to allow oil to flow through the bearings at the rateforced y the pumps. As in any other positive displacement pump, themaximum discharge pressure is limited for overpressure protection pur-poses - by a pressure relief valve installed in the discharge line of each jacking o l pump.UpsetsMaintenance of proper oil pressure at the bearing inlet is extremely important for safe and trouble·free operation of the turbine generator. Discussedbelow r t r cases of improper o l pressure.

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Course 234 Turbine and Auxiliaries Module 10 PPROV SSU REFERENCES Too low pressure the lubricating oil:

May cause turbine generator damage as follows:a The bearing s whose inlet oil pressure is too low may get dam-aged due to inadequate cooling and lubrication

When the bearing inlet oil pressure decreases so does the oil flowthrough the bearing. This impaits bearing cooling and fotmation ofthe o l wedge in the bearing. The resultant overheating and possiblerubbing can damage the bearing babbilllining. More infonnation onthe damage mechanisms is provided in module 234-14.

b) T he whole macbine may snffer a large scale damage if loss of oilhas damaged many bearings.Severe damage to many bearings can cause large vibtation of the turbine generator rotor. This can lead to rubbing damage to turbineseals and possibly blades, further.amplifying the vibtation. Thegenerator hydrogen seals can so fail even seal o l is available), the generator bearings are destroyed. This may result in a generator hydrogen fire.

Should cause a turbine trip to prevent or at least minimize turbinegenerator damage.This action, although absolutely necessary, results in loss of produc-tion.

In tum too low jacking oil pressure: May damage tbe affected turbine generator bearing s due to inadequate lubrication.

This can happen when turbine speed is too low for adequate hydrodynamic lubrication nf the bearings. The resultant rubbing in the bearing s)can wipe oU the babbilllining.

2. May result in unavailability of tbe turning gear.When jacking oil pressure is too low the turning gear may become una-vailable due to:- an interlock in the gear motor control circuit disconnecting

power supply to the motor, or- the motor tripping on overload as loss of jacking oil makes turning

the turbine generator rotor more difficultRecall that unavailability of the turning gear causes certain adverse con-sequences and operating concerns For example it can lead t exces-sive rotor hogging while shutting own the turbine. Or, it can force adelay during turbine startup, resulting in loss of production. It must be

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APPROVAL SSU Course 234 - T ur bi ne a nd Auxi li ar ie s - M od ul e 10stressed that these consequences. as much as they are unwelcome, arefar more preferable than the very likely damage to poorly lubricatedbearing s).

The major concern caused by t oo high pressure of lubricating or jack-ing oil is that it ,increases the risk of system overpressure failure the relief valve s) failed to operate. The resultant oil lea < causes operatingconcerns such as:A r r hazard the oil comes in contact with a hot turbine casing orstearn pipeline;Loss of oil pressure the leak is large enough;An environmental hazard as the leaking oil can contaminate viafloorsumps the station effluent.

Protective actions

NOT S R F R N S

c Obj 1 1 c)F rom the above, you can seethat some of these consequences can be quite serious.This applies particularly toloss of lube oil pressure. Toreduce the risk of possibleequipment damage, properprotective actions shownin Fig. 10.1) are performedautomatically upon droppingbearing inlet oil pressure.Due to station specific differences, the diagram is simplified, and therefore the sequence and the type of theprotective actions in your station may differ somewhat.

Fig. 0.1. U utolnll a P:f OteotIu m:Iona andropping bMring Inlet olII MU ....Overpressure protectionThe following features are employed in the turbine lube oil system for overpressure protection:I. A lube oil relief valve installed in the common discharge piping of theoil pumps.

This protection is particularly important in those units where the main oilpump is a positive displacement type. However, even when the mainoil pump is centrifugal, it can produce excessive oil pressure in the eventof abnorntally high turbine overnpeed*.

c Obj 1 1

• R ec al l t ha t di sc ha rg epressure of a centrifugalpump increases quicklywith rising pump speed.

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Course 4 Turbine and Auxiliaries Module 10 PPROV L ISSUES REFERENCES

infonnation isovided on page 12.

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2. One pressure relief valve in each jacking oil line.This protection is necessary because the jacking oil pumps, being posi-tive displacement type can generate excessive discharge pressme whenthe oil line is blocked.

3. he explosion door s in the lube oil t nk cover.This fearure protects the tank against damage due an explosion of theatmosphere inside .

SUMM RY THE KEY ON EPTS• When oil is supplied by the main oil pump, the besring inlet oil pressureis controlled by the lube oil reliefvalve. Tbe valve operates by spillingthe swplus oil back the tank when the pressure reaches a certain level.• When oil is supplied by the auxiliary oil pump, the bearing inlet oilpressure is also controlled by spilling the surplus oil the tank. De-pending on the station, this is performed eitherby the lube oil reliefvalve or by the auxiliary oil pump regulator.• When the emergency oil pump supplies oil, its pressure at the bearinginlet is nOl controlledbecause it is well below the setpointof the lube oilreliefvalve. Under emergency conditions, it is important supply allavailable oil the besrings in an attempt maintain their oilpressure ashigh as possible.• Thejacking oil pressure at the besring inlet is not controlled. sthe oilis supplied by apositive displacement pump, its pressure rises until the

bearing resistance to the oil flow is overcome. This happens when theturbine generator rotor is lifted off the bearings.• Low lube oilpressure can damage turbine generator bearings due to in-adequate cooling and lubrication. When many bearings have failed.other parts of the turbine generator can also suffer damage due to highvibration and rubbing. n automatic turbine trip should occur pre-vent/minimize damage.• Low jacking oil pressure can damage·turbine generator bearings whenturbine speed is low for adequate hydrodynamic lubrication. Alsothe turning gear roay become unavailable.• Too high oil pressure increases the risk of overpressure failure in thelube oil system.• The following protective aetlons listed in the orderof dropping pres-sure) should occur in response to low bearing inlet oil pressure: the aux-iliary oil pump is started up, an annunciation Is given, the emergency oilpump is started up and finally, the turbine is tripped.


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Course 234 urbine nd Auxiliaries Module 10 APPROVAL ISSUER F R N S

Obj 10 2 b

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When the bearing inlet oil is too hot the following adverse consequencesand operating concerns result: Increased risk of bearing damage due to:

- Ovemeating - as the hot oil cannotkeep the bearing metal temperature at th safe level;Metal-to-metalcontact between the shaft and the bearing lining;- Increasedvibration levels.

The last two effects are caused by reduced oil viscosity due to increasedtemperature resulting in a thinner oil wedge in th bearing. To understand it, note that it is th viscosity forces between the oil and the spinning shaft surface which force the oil into the wedge gap underneath thshaft Without these forces no oil wedge would be fonned. Thuswhen these forces decrease so does the oil wedge. Obviously its re-duced thickness increases the risk of robbing between the shaft and thebearing lining. It also reduces dampening rotor vibration which leadsto increased vibration levels. Note that the bearing oil wedge is one ofthe most significant sources of rotor vibration dampening. This isachieved much the sameway as hydraulic shock absorbers dampen vibration the car suspension.

2. Loss of production due to forced protective adionsAs mentioned above, high bearing metal temperature or vibration canforce turbine unloading or a trip, resulting in a loss of production whichcan be attributed to inadequate oil temperature control.

SUMM RY OF THE KEY ON EPTSo When temperature decreases too much, oil in the bearing becomes soviscous that it clings to th shaft surface which drags it around the bearing. This makes the oil wedge in the bearing los its stability. The pulsatingwedge excites high rotor vibration referred to as oil whip or oilwhirl.• Too low temperatme and hence too large viscosity the bearinginlet oil causes the bearing oil flow to decrease due to increased frictionin the oil supply piping. The reduced oil flow may be too small for adequate cooling, causing bearing overheating and possible damage.• When bearing oil is too hot it cannotm int in the bearing metal temper-ature within its safe range. Bearing damage due to overheating may result.o Reduced viscosity of hot oil impairs the formation of an oil wedge in thebearing. As the wedge becomes thinner, turbine vibration levels mayrise due to reduced dampening, and the risk of robbing in the beating increases.


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APPROVAL ISSUE Course 234 Turbine and Auxiliaries Module 1• Through high bearing vibration or metal temperature. improper bearinginlet oil temperature may force protective actions resulting in a loss of

productionYou can now work on assignment questions 1 5.

LUBE OIL IMPURI11ES n this section. you willieam about the four major impurities turbine lu-bricating oil: water oxidation products. gases. and abrasive particles. Theadverse consequences/operating concerns major sOurces and means moval each these impurities are described. Two general operatingpractices used to ensure the proper purity of the oil are also discussed.W TERSources Absorption of atmospheric moislore.

During turbine operation atmospheric air which always contains somewatervapour enters the oil system via the bearing oil seals. The in-leakage happens because: The shaft surface velocity is too large to allow for contact betweenthe shaft and the seal. Thus. a leak path is open. Slightly subatmospheric pressure is maintsined inside the bearinghousing and its drain line by the vapour extraction fans installed onthe lube oil tank cover. Why is this pressure maintsined? First. tprevent oil mist from escaping past the bearing oil seals into the tur-bine hall. Second. to prevent accumulation hydrogen and oil va-pour in the lube oil tank atmosphere which could create an explo-sion hazard.Some otherpossible leak paths include poorly fitring or missing gasketsin the drain lines or lube oil tank coverDuring turbine shutdown the oil tank may be open for inspection. re-sulting in a large contact area between the oil in the tank and the humidair in the turbine hall. Because during shutdown the oil in the tank canbe relatively cool condensation of moisture is promoted.

A leaking turbine gland seal.When a gland seal is leaking steam the humidity of the sunounding airis increased. The humid air enters the adjacent bearing. as describedabove. This is promoted by a very small distance between turbine bear-ings and the adjacent gland seals.

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Course 234 _ Turbine n Auxiliaries Module 10 PPROV SSU R F R N S 3. A leaking oil cooler.

Since water is used for oil cooling a leaking cooler may result in con-tamination oil with water. nmost stations this is prevented duringnormal operation by maintaining the oil pressure above the cooling w -ter pressure. However even in these stations. water in leakage can oc-cur during a turbine shutdown when the oil is not pressurized.Note that this ammgement - where during nonnal operation oil pressure is maintained. above cooling water pressure can result in oi l leakinto the cooling water n with it into the environment. To minimizepollution prompt actions must be taken to locate and stop the leak. e-tails re left for the station specific training.

4. Makeup additions nf contaminated oil.Adverse consequences nd operating concernsThe typical adverse consequences/operating concerns caused. by the pres-ence of water in lube oil are: Degraded oil properties due to

Fonnation o emulsions whose lubricative properties are lower thanthose of pure oil;- Washing out of special oil additives ego rust inhibitor;- Accelerated oxidation of the oil and its additives.2. Promoted corrosion and scale formation in the equipment to whichthe oil is supplied.These consequences result in accelerated wear equipment such asbearings and generator hydrogen seals. Evenmally bearing or seal failuremay occur forcing a unit outage. The potential for serious damage is in-creased in the units where turbine oil is used as a hydraulic fluid in the tur-bine governing system. Recall from module 234-7 that poor quality of thisfluid can cause massive destruction of the turbine generator and the nearbyequipment if the turbine valves failed to operate s required upon a load re-jection or turbine trip.RemovalWater is removed from the oil by: he lube oil purifier.

Depending on the station the purifier is of either the centrifugal or thevacuum treatment type. The fonner removes free water due to the dif-ference berween the oil and water densities but cannot separate emulsified. or dissolved. water. Vacuum purifiers available in new stations donot have these limitations.Page 10


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APPROVAL SSU Course 234 _ Tw bine ancl Auxiliaries - Module 10NOTES REFEREN ES2 The vapour extraction fans.

The fans installed in the lube o tank cover, remove water vapour thatis released from the surface of the hot oil in the tank3. Drainage from t he bott om of th e oil tank

This ca n be done during a long outage when water, being heavier thanoil, collects at the tank bottom.

SUMM RY OF THE KEY CONCEPTS• Water gets into turbine lube oil due to absorptioo of humid air A leaking turbine gland seal or oil cooler, or makeup additioo of contaminatedoil can be other sources.• Water degrades oil properties as it forms emulsions, washes out oil ad-ditives and accelerates oxidation. Water also promotes cOITOSion and

scale formation in the equipment through which the oil is circulated.Accelerated equipment wear and possible failure may result• During normal operation, water is removed from the oil by the oil purifi

er and the vapour exttaetioo fans. During a long outage, water can alsobe drained from the bottomof the lube oil tankOXID TION PRODUCTSSourcesNonnally. oxidation products are formed th e oil itself due to complexchemical reactions between the oil, air, water and metals. The rare of oxidation increases quickly with rising temperature. Water and some metals likecopper are also known to accelerate oil oxidatioo. The final products areresins, sludge and organic acids.Oxidation products can also be a dd ed t o th e system when contaminatedmakeup oil is used.Adverse consequences and operating concernsThe presence of oxidation products n the oil results in the following adverse consequences/operating concerns:I Degradation of th e oil lubricative properties by sludge and resins.2. Accelerated corrosion of the s ys te m c om po ne nts msinly by acidic compounds.

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APPROVAL ISSUE oune234 - Turbine and Auxiliaries - Module 102. Accelerated oil oxidation and system corrosion due to the presence oiair and carbon dioxide*.3. Possible oil foaming which worsens the lubricating and cooling properties of the oil and may impair pump perfonnance, to name a few possi

ble consequences.As described in the previous sections, accelerated corrosion and degradedoil properties result in faster equipment wear and possibly failure.RemovalOases are removed from the oil by:1 The vapour extraction fans wmen connnuouS y vent me 011 taI1K toatmosphere and maintain slightly subatmospheric pressure in the tank;2. The hydrogen detraining tanks and, in some stations, the seal oilvacuum treatment plant in the generator seal oil system; 3. The oil purifier it is of the vacuum treatment type. Here, de-gassing occurswhen the solubility of gases in the oil is greatly reducedby a combined effect of highvacuum and elevated temperature .

SUMMARY OF THE KEY CONCEPTS• r enters the lube oil systemdue to slightly subatmospheric pressure inthe lube oil tank Hydrogen and carbon dioxide dissolve in the oil flowing through the generator hydrogen seals. Oil vapour is produced in theoil tank and bearing drain lines which are only partially filled with hoto l• Amixture of hydrogen, oil vapour and air in the oil tank atmospherecreates an explosion and fire hazard. r and carbon dioxide in the oilresult in accelerated oil oxidation and systemcorrosion. Gases in the oilcan cause foaming• Oases are removed from the o l by the vapourextraction fans, hydrogendetraining tanks and (where installed) the seal oil vacuum treatment plantin the generator seal oil system.

ABRASIVE PARTICLESSourcesTypical sources of abrasive particles in lube oil include:I. Normal equipment wear and corrosion which generate tiny metalparticles, fibres from the gaskets in the system, flakes of paint and rusl,etc. Equipment breakdown eg failure of the main oil pump impeller)can also produce largerdebris.

NOlES R F R N S Recall that carbon dioxid- when combined with w

te r - creates corrosive Cabonie aeid.

• About 5·10 kPa(a) and70-80·C.

Obj 1 3 cotttlttued

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Course 234 urbine and Auxiliaries Module 10 PPROV L ISSU R F R N S

Obj 10 3 b >

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2 Dirt in the air which is sucked into the subatmospheric part the sys-tem as described earlier3. LeRovers aRer maintenance under dirty conditions followed by in-

adequate system flushing. Makeup additions of dir ty oil.Adverse consequenceThe major adverse consequence caused y abrasive particles in the oil is thatit accelerates wear and promotes failure the equipment served bythe oil. For inslance the beating babbitt surfaces shaft journals and gener-ator hydrogen seals can get scratched by large particles. Vcry fine particlescan over relatively long periods time lap journals causing waviness. the oil is used in the tmbine governing system abrasive particles can causesystem rnalfunction and possibly catastrophic failure as described in mod-ule 234 7.RemovalAbrasive particles are removed by strainers filters and the oil purifier.

SUMM RY OF THE KEY CONCEPTS• Abrasive particles are formed in the oil system due to normal equipmentwear and conosion and occasionally due to equipment failure. Theycan be brought into the system with the air leaking into the subatrnos-

phetic part of the system. r maintenance workmanship and makeupadditions of dirty oil are other possible sources.• Particles in the oil accelerate wear and promote failure the equipment

served y the o• Particles are removed from the oil by strainers filters and the oil purifier.GENER L OPER TING PR CTICES USED TOENSURE S TISF CTORY PURITY OFLU RIC TION OIL1 Proper operation the oil purification equipment as required or

recommended in the operating manual. For example: The oil purifier should be used continuously. Even during turbine

shutdown the purifier should not be down for more than one weekunless the lube oil system is in the drained state. Otherwise absorp-tion atmospheric moisture can result in excessive water content inthe oil. For best results purifier operation should be monitored.


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APPROVAL SSU Course 234 - Turbine and AuxiliarieJ - Module For instance, proper vacuum and temperamre should bemaintainedin the vacuum treatment type purifier.

- The pressure drop Ap across filters should be monitored, and thecartridges changed when the Ap is too high cartridge plugged ortoo low cartridge ruptored or missing .

- Propervacuum should be msintained in the oil tank to prevent accumulation of water and gases.

Routine analyses of the oil and, appropriate corrective actions ifnecessary. Important points are:- Strict adherence to the oil sampling procedure is extremely impor-tant, because improper sampling yields misleading results which

can lead to serious operational problems;- Proper corrective actions mustbe taken when the analysis results in

dicate abnormal levels of impurities. For instance, turbine glandseals and oil coolers should be checked for leaks when high watercontent in the oil has been found.

In recent years, gaining popularity are wear-particle analyses. Performed inaddition to the traditional chemical analyses, they monitor the quantity, sizeand type of particles in the oil. This valuable tool of preventive msintenancecan provide an early warning of upcoming failure, and usually can pinpointthe location s of abnormal wear. Typically, these analyses are done by offsite specialized laboratories.

SUMM RY OF THE KEY CONCEPTS• To ensure satisfactory qualityof turbine oil, the purification equipmentmust be operated properly. In addition, oil purity is monitored by taking routine samples for analyses. Strict adherence to the sampling pr -cedure is very important to avOid misleading analysis results.

OIL TANK LEVEL UPSETSAdverse consequences and operating concernsThe major adverse consequence/operating concern caused by too low tanklevel is impaired pump performance due to cavitation and possibly vapourlocking or gaslocking.The lower the oil level, the smaller the suction head of the pumps in thetank. Pump cavitation and eventually vapourlocking can result. Thelowered level can also lead to ingress of gases from the tank annosphereinto the pump suction piping, and then the pump itself. n excessive aceu

NOT S R F R N S

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Course 234 urbine nd Auxiliaries Module 10 APPROVAL SSU R F R N S

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Pages 19 22 ¢

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mulalion of gases in the pump can decrease its capacity and fmally resultin pump gaslocking.Severe pump cavitation and entrainment of gases not to mention vapour-and gas locking accelerate pump wear and may result in failure.When the pump performance is severely impaired. the bearing inlet oilpressure is decreased. The attendant adverse consequences and operat-ing concerns have been descnbed earlier in this module.Too high tank level increases the risk of tank overfill The resultantoil spill has its own adverse consequences such as an environmental hazardCausesUnder the assumption that the level instrumentation is fine typical causes ofoil t nk level alarms are as follows:I A low level a arm can e caused by an oil leak ego through a bearing

seal or in a cooler2 A high level alarm may result from:

Excessive addition of makeup oil; Large water in leakage in an oil cooler; Large quantitiesof oil descending into the tank from other parts the system when it is being shut down

SUMM RY OF THE KEY CONCEPTS• Too low lube oil t nk level can resUlt in imp ired performance and accel-erated wear of the operating oil pumps possibly leading to loss of oilpressure The upset can be caused by an oil leak in the system• Too high oil t nk level increases the risk oil spill due t t nk overfill.This level upset can be caused by excessive additions makeup oil or

large water in leakage in a cooler. Drainage oil into the t nk when thesystem is being shut down is another possible causeYou can now work on assignment questions 6·10.


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Course 234 Turbine and Auxiliaries Module 1 PPROV SSU R F R N S c The major operating concern caused y too high oil pressure is

3. Dropping beating inlet oil pressure results in the following auto-matic protective actions,listed in the order of decreasing oil pres-sur

iliiiiv

b The turbine lubricating oil system is protected against ovetprOs-sure by:i

l

4 no action is taken and operation is continued improper bearing inletoil t mp r tur can result in equipment damage as follows: the oil is too cool, damage cao occur due to:

il

b oo hot oil cao cause damage through:iliii

5. When temperature rises, oil viscosity decreases / increases .b Oil whip refers to flow pulsations in the lube oil system due topoor pump performance. False / true

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PPROV L ISSU Course 234 Turbine and Auxiliaries Module

c Too low bearing inlet o l temperature can result in very high vibration the turbine generator referred to as _

The vibration is generated as follows:

d Excessively cool oil at the bearing inlet can cause bearing overheating due t _

e Too hot o l at the bearing inlet impairs its lubrication because

the bearing oil is too hoI turbine generator vibration can in-creasebecause _

6 Typical sources lube oil impmities are as follows:a Water:

iiiiiiIv

b Oxidationproducts:iii

NOT S R F R N S

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Course 34 urbine nd Auxiliaries Module 10 PPROV L ISSU REFEREN ES c Gases:

iii

d Abrasive particles:iii

Iv6 The presence of impurities in lube oil causes the following adverseconsequences operating concerns:

a Wateriii

b Oxidation productsiii

c Gases:iii

d Abrasive particles:

8 Lube o l impurities are removed by the following meansa Water:

iii

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PPROV L ISSU Course 234 Turbine and Auxiliaries Module 1NOT S R F R N Sb Oxidation products:

iii

c Gases:iii

d Abrasive particles:iii

9. o ensure satisfactory purity of lube oil, the following generaloperating practices are used:i

ii

b During a turbine shutdown, there is no need to use the oil putifi-er. False truec n oil fllter cartridge may have to be replaced when thepressuredrop across the fllter is abnonnal1y low. False trued Strict adherence to the oil sampling procedure is very important

ec use

10. oo low lube oil tank level can impair pump perfonnance due to

The resultant adverse consequences operating concerns are:iii

b This upset can be caused y _

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Course 1 34 _ TUrbine and Aux111anes MOdule 1U PPROV L ISSU R F R N S c Abnonnally high tank level can result in _

d A high lube oil tank level can be caused by:iil

Before you move on to the next module review the objectives and makesure that you can meet their requirements

by: I ENIDRevised by: 1 Jung ENTD

Revision date: June 1994

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PPROV L ISSU Course 234 - TutbiI. 4ld Auxiliaries - Module 10

AUXILIARY 1 L.....OIL PUMP IREGULATOR

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