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ENERGY RECOVERY FOR

GAS PROCESSING

Recovery of the hydraulic energy in liquid-basedgas processes has always held promise for improv-ing the economics of plant operation. However, noenergy recovery turbine (ERT) has combined the sim-plicity, low cost,and reliability of the PEITurboChargerTM.

Pump Engineering, Inc. has developed a revolu-tionary energy recovery device that will be equallyappreciated by the OEM and the end user; the Hy-draulic TurboChargerTM or TURBOTM.

With three U.S. patents and other patent applica-tions pending in the U.S. and other countries, theTURBOTM represents advanced technology in en-ergy recovery.

PROVEN AROUND THE WORLDHundreds of TURBOsTM are operating around theworld in services similar to gas processing. Loca-tions include the United States, Middle East, Carib-bean, Canary Islands, and East Asia.

DEFINITION OF TERMSPSI Pounds per Square InchPSIG Pounds per Square Inch GaugeGPM Gallons per MinuteHP HorsepowerkW KilowattERT Energy Recovery Turbine

EXTENSIVE SELECTIONPump Engineering offers a complete line of TURBOsTM

suitable for flows from 20 to 4,000 gpm per unit.

TABLE OF CONTENTS

Background........................................ 2Features.............................................. 3TurboCharger Application.................... 4Performance Calculation...................... 5Calculating Turbo Boost....................... 6Feed Pump Considerations...................7Contactor Pressure Control..................7Centrifugal pump / Turbo Example........8Positive Displacement Pump/Turbo.......9Plant Capacity Increase Example..........10Installation.......................................... 11Starting, Operation, Maintenance..........12

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With just one moving part, no seals togenerate drag, and virtually 100%volumetric efficiency, the TURBOTM isinherently efficient. In fact, its efficiencyhas set new standards for centrifugalfluid machinery.

SafetyThe Turbo’s rotor is entirely containedwithin the casings, hence there are noshaft penetrations of the pressureboundary and no shaft mechanicalseals. The Turbo is “zero emissions”and inherently safe. This is expeciallyimportant when handling gas-processing fluids that can releasehydrogen sufide or other dangerousgases into the environment.

MaintainabilityThe TURBOTM is designed to beoverhauled in one to four hours,depending on size, using only handtools.

ReliabilityElimination of shaft seals andseparate lube systems (theTURBOTM is lubricated by thepumpage), as well as single stagedesign means that there are veryfew parts to fail. Use of high gradematerials such as second generationduplex stainless steel, titanium, andceramics add to reliability.

This manual describes several waysthe TURBO

TM can be used in gas

processing plants to obtain energysavings, reduced capital costs, andincreased plant reliability.

Applications presented in thismanual should be considered asguidelines. Always confirm thefeasibility of a condition change withthe equipment suppliers involved.

DesignThe TURBOTM is an integral turbine-driven centrifugal pump. The unit isdriven by the high pressure fluid passingthrough the turbine section. The turbineis a single stage radial inflow type(similar to a reverse running pump).The pump is a single stage centrifugaltype with its impeller mounted on theturbine shaft.

Two styles of TURBOsTM are offered.The smaller units use a one piece centerbody that houses both the turbine andpump sections. Larger units (seeFigure 1) use a separate pump casingto permit interchangeability of casingsizes for greater hydraulic range.

EfficiencySince the unit is not mechanicallydriven by a motor, the rotor freelyseeks a running speed that maximizesefficiency.

Designed specifically for hydraulic energy recovery, the TURBOTM addresses the major issues facing the gasprocessing designer and user including design simplicity, efficiency, reliability, maintainability, ease of fieldrepair, and versatility.

Figure 1 HIGH PRESSURERICH AMINE

HIGH PRESSURELEAN AMINE

LOW PRESSURERICH AMINE

LEAN AMINE

PUMP IMPELLER

PUMP BEARING

CENTERBEARINGSHAFT

TURBINEIMPELLER

THRUST BEARING

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FEATURESCasingsVolutes are machined in both the pumpand turbine casings of each Turbo. Thenozzle connecitons are ANSI 600#class flanges. For models HPT-150and above the pump casing is radiallysplit for easy assembly/disassemblyinspection and attached to the turbinecasing by heavy hex nuts. Themaximum operating pressure is 1500psi.

RotorThe turbine and pump impellers areclosed, radial flow design for optimumhydraulic performance and efficiency.The pump side impeller is keyed to theshaft and mounted with a shrink fit againsta shoulder. The turbine impeller is castintegral with the shaft. The complete rotoraassembly is dynamically balanced toISO G 4 precision. All shaft surfacesthat are in contact with journal or thrustbearings have a plasma sprayed ceramiccoating of chrome oxide.

BearingsThe turbo utilizes two journal bearingsfor radial rotor positioning and onehydrostatic thrust bearing to carryunbalanced axial thrust. All bearings aremade of aluminum oxide and arelubricated by the pump liquid. For gasprocessing, product lubricated bearingsoffer the following benefits:• No grease or oil inventory• Elimination of periodic maintenance• No oil or shaft seals• No possibility of operation without

lubrication

Immunity to Ambient ConditionsThe TURBOTM does not have shaftpenetrations or external bearings. Thus,the TURBOTM can operate in the hottestdesert environments, extreme dust, watersprays, etc. (the TURBOTM can operateeven fully submerged in water). In short,the TURBOTM can handle virtually any

external environment.

Flexible InstallationThe TURBOTM may:• be mounted in any orientation• be located anywhere in the system

including next to the absorber toreduce fluid piping costs

• discharge fluid against abackpressure.

Flow ControlThe Turbo can be equipped with anoptional auxiliary turbine nozzle andcontrol valve that allows amine flowand pressure to be adjusted tomaintain proper liquid level in thecontactor. All of the amine passesthrough the TURBOTM for maximumenergy recovery efficiency. For moreinformation on flow control see page7.

Low NoiseSince the TURBOTM is entirely self-contained and uses journal bearings,its noise level is lower than other flowmachines of comparable capacity and pressure differential. On lower pressureapplications, often the only way to verify that the Turbo is operating is to observethe pressure guages for the Turbo boost pressure. Since the Turbo dramaticallylowers the size and power of the high pressure pump, the overall noise levelassociated with this pump and its driver is also significantly reduced.

Customized Design and ManufacturingEvery TURBOTM is designed and manufactured to meet the customer’s spe-cific hydraulic conditions. A set of proprietary computer programs developedby PEI calculates the required dimensions of the hydraulic passages and auto-matically generates the CNC (Computer Numerical Control) programs to con-trol the machine tools in the production process.

Advantages of custom machining includes:• a perfect hydraulic match every time• smooth hydraulic passages for added efficiency• minimized lead times as PEI need keep only a few types of castings in

inventory to cover a broad hydraulic range.

Compact Size and Light WeightA unit able to handle 100 gpm (22 m3/hr) of amine can be held in one hand.The light weight combined with the flexibility described above insures the low-est cost and most convenient installation possible.

HPT-50

HPT-1200

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STRIPPER

CONTACTOR

LEANAMINE

RICHAMINE

STRIPPER

CONTACTOR

LEANAMINE

RICHAMINE

Figure 2 illustrates a simple liquid ab-sorbent system. For the purpose of de-scription, the term “amine” is used todesignate any liquid absorbent. Theprinciples described hold equally true forany absorbent.

High pressure amine passes through thecontactor where it absorbs carbon diox-ide and hydrogen sulfide from the gas. Theamine, now called “rich amine” passesthrough a pressure reduction (throttling)valve. The depressurized amine is admit-ted to a stripper where the contaminantsare removed from the amine. The “lean”amine is then pumped back into thecontactor thus completing the process.

The required flows and pressure differ-entials are often high enough to makepumping energy a major cost factor.Most of that pumping energy, however,is lost in the pressure reduction valve.A large savings is obtainable if the hy-draulic energy normally lost in the re-duction valve can be recovered and “re-cycled” in the process.

Figure 3 shows the TURBOTM actingas a pressure booster in the lean aminestream. The rich amine passes through theturbine section where it gives up its hy-draulic energy. The feed pump boosts theamine pressure to typically about 35-50%of the contactor pressure. The amine thenpasses through the pump section of theTURBOTM where it receives the final pres-sure boost.

The TURBOTM is entirely engergized by the high pressure richamine. The pressure reduction valve has been eliminated, and thesize of the high pressure feed pump has been reduced. As will beshown later, the TURBOTM provides a significant reduction in pump-ing equipment costs. The savings may exceed the cost of theTURBOTM thus making the TURBOTM a zero or even negative-cost component.

Figure 2

Figure 3

10 stage pump

5 stage pump

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Performance Calculations

An energy recovery turbine is usuallyrated as having a certain efficiency basedon the conversion of hydraulic power intomechanical shaft power. However, the liq-uid absorbent gas purification processrelies on a varying absorbent pressure.Therefore, the most appropriate use ofthe recovered energy is to repressurizethe amine. Thus, the ERT shaft output ismechanically transmitted to the feedpump which then converts that powerback into hydraulic power in the aminestream.

A better measure of ERT efficiency is theratio of the hydraulic energy returned tothe lean amine to the amount of hydraulicenergy available in the rich amine. Thisratio, the hydraulic transfer efficiency,or nte, is defined as:

nte = Hout / Hin [1]where Hout = Hydraulic energy

transferred to the leanamine

Hin = Hydraulic energyavailable from the richamine

In the case of a reverse running pump ERT,nte is calculated by:

nte =(nert) (nmd) (np) [2]Where nert = ERT efficiency

nmd = mechanical powertransmission efficiencybetween ERT and feedpump

np = feed pump efficiency.

Assume an amine system uses a multistagefeed pump rated at 74% efficiency at theoperating point. The system also employs amultistage reverse running pump as an ERTthat displays an efficiency of 70% at theoperating point. The two units are coupledby a double extednded shaft motor. The datais summarized as:

nert = 70% or 0.70nmd = 100% or 1.00 (no loss)np = 74% or 0.74

Substituting the above values into equation[1] yields an energy transfer efficiency, nte,of 0.52 or 52%. That is, 52% of the hydraulicenergy in the rich amine is converted into

hydraulic energy in the lean amine. Therest of the energy is lost as heat.

Unlike conventional ERT’s, the energytransfer efficiency of the TURBOTM is in-dependent of the feed pump efficiency.Thus, Figure 2 can be used to find theapproximate hydraulic energy transfer ef-ficiency for the TURBOTM.

Knowing nte makes calculation of theTURBOTM pressure boost, ∆Ptc, verysimple:∆Ptc = (nte) (Rr) (Pri - Pro) [3]where Rr = rich flow / lean flow

Pri = Rich amine pressureentering TURBOTM

Pro = Rich amine pressureleaving TURBOTM

The amine pressure drop, ∆Pr, is definedas:

∆Pr = Pri - Pro [4]

Note that Rr is typically equal to 1.0 thusequation [3] simplifies to:

∆Ptc = (nte) (Pri - Pro) [5]

Figure 4

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$131,062 PER YEAR COST REDUCTION *163kW SAVED

NATURAL GAS PROCESSING ENERGY RECOVERYFOR

HYDRAULIC TURBOCHARGER HPT 450

RICH AMINE READY FOR STRIPPINGRICH AMINE EXITING CONTACTOR AT HIGH PRESSUREADDITIONAL PRESSURE INCREASE PROVIDED BY TURBOLEAN AMINE PARTIALLY PRESSURIZED BY MOTOR DRIVEN FEED PUMPLEAN AMINE LEAVING STRIPPER

COMMENTS

* - $0.10/kW/hr, 8000 hr PER YEAR OPERATION

LOCATION

50054321

500500500500

FLOW(gpm)

60

PRESSURE(psig)

98099546120

ADJUSTMENT OF

TM

NOZZLE VALVE.AUXILIARYTHE TURBO

BY AUTOMATICIS MAINTAINEDAMINE LEVELNOTE:

12

3

4

5

The following example illustrates howto calculate the pressure boost gener-ated by the TURBOTM. In this ex-ample, the flow and pressures are asfollows:

Q = 350 gpm (amine flow)Pri = 980 psig (rich amine

pressure to TURBOTM)Pro = 60 psig (flash tank pressure)Plo = 995 psig (contactor pressure)

For 350 gpm of feed flow, nte is readfrom Figure 2 as 58%.

Calculating Amine Pressure Boost

Substituting the above data into equa-tion [5] yields:

∆Ptc = (.58) (980-60)=534 psi

The feed pump discharge pressure Pliequals the contactor pressure, Plo mi-nus the TurboTM boost ∆Ptc or

Pli = (995-534) = 461 psi

Assumming the inlet pressure to thepump is 20 psig then the pump differ-ential pressure is only 441 psig.

A more accurate analysis would ac-count for pipe and fitting pressure lossesas well as changes in elevation. Also,the specific TURBOTM model would beselected to permit a more precise de-termination of the efficiency.

As will be shown later, the large re-duction on the required pump differen-tial pressure has a very positive and sub-stantial impact on the cost and type ofpump and motor selection.

Figure 5

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CENTRIFUGAL AND

POSITIVE DISPLACEMENT FEED PUMPS

Since the TURBOTM is a self-containedunit, it can be used in conjunction with anytype of feed pump such as:

• vertical turbine• horizontal split case• power (reciprocating)

However, the characteristics of the feedpump can influence the TURBOTM installa-tion.

Reciprocating Power FeedPumps

Positive displacement (PD) pumps deliveressentially a constant flow rate regardlessof discharge pressure (assuming a con-stant-speed driver).

When used with a Power Pump, theTURBOTM simply reduces the Power Pumpdischarge by an amount that equals theTURBOTM boost pressure of the lean aminestream.

The implications are many, including im-proved service life of:

• plunger packing• valves and seats• crosshead and crank bearings.

Also, the power end will run cooler due toreduced frame loading. Likewise, the mo-tor will run cooler and increased bearinglife can be expected.

Note that the Power Pump can be sized todevelop the full pressure so that if theTURBOTM were not in service, the plantcan be operated normally.

The TURBOTM can also improve the per-formance of gas-charged pulsation damp-eners. The reduced feed pump dischargepressure permits a reduction in the damp-ener charge pressure which makes thedampener “softer” thus better able to at-tenuate pressure pulsations in the fluidstream.

Centrifugal Feed Pumps

These pumps deliver a flow rate equal tothe capacity at which the system resistancecurve crosses the head-capacity curve ofthe pump.

Use of the TURBOTM can have a dramaticeffect on pump selection. The very largepressure boost reduces pump dischargepressure such that:

• many fewer pump stages are needed• much smaller motor and switchgear• extended shaft seal life can be expected

In fact, the feed pump pressure is reducedto such an extent that a single stage feedpump is often sufficient. The greatly re-duced capital and maintenance costs canoffset the cost of the TURBOTM severaltimes over.

CONTACTOR PRESSURE CONTROL

Every HPT is equipped with a flow control valve called the Auxiliary Nozzle Valve. Thus, the contactor pressure valve normally usedin amine plants is replaced by the HPT. Flow and pressure adjustment can meet typical gas processing requirements. Contact PEI ifthe contactor pressure can vary more than 25% at a constant flow. Note that the entire rich amine flow passes through the turbineimpeller regardless of the valve setting, thus ensuring maximum energy recovery.

A conventional reverse running pump requires two (2) pressure control valves. One valve adds flow resistance to the rich aminestream when the contactor pressure requirement exceeds the system resistance of the turbine (i.e. the operating point is above thehydraulic curve in the following figure.)

The other valve is used to bypass rich amine when the desired contactor pressure is below the curve. In either case, the energyrecovery of the ERT is reduced. The broad operating envelope of the TurboTM discounts these problems using one auxiliary nozzlevalve.

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Starter$16,000

nert = 70%np = 74%

nm = 93%

500 hp TEFC Motor & Multistage API Pump

nm = 93%

np = 75%

Starter$8,000

HPT-600$49,055

nte = 61%

200 hp TEFC Motor & Pump Engineering’s HPG Pump

MEDIUM-CAPACITY SYSTEM

This example compares a feed pump - TURBOTM package with a feed pump - reverse running pump package. TEFC 3600 RPM(60 Hz) motors are assumed. Data are based on manufacturer’s published performance data, published prices and estimates.Electricity cost is assumbed to be $.10/kw-hr.

TURBOTM

Total equipment costs = $97,555Electrical power consumption = 134 kW

Flow (gpm) Pressure (psi)1 600 302 600 3883 600 8704 600 8505 600 60

Total equipment costs = $151,000Electrical power consumption = 164 kW

Energy Recovery Turbine

Note: For this example,the overall efficiency isNte= (0.074)(0.70) = 0.52

Flow (gpm) Pressure (psi)1 600 302 600 8703 600 8504 600 60

TURBOTM Benefits• The TURBOTM saves $68,000 in capital costs AND $33,300 per year in energy costs over the ERT

• The feed pump used with the TURBOTM is less expensive to install and overhaul

• The smaller starting electrical load will permit reduction in transformer and generator capacity

• Other cost savings include reduced foundation size

Figure 6

Figure 7

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The TURBOTM makes energy recovery cost effective even on small systems. This example calculates cost savings fora small system using a positive displacement feed pump.

SMALL AMINE SYSTEM

Reciprocating Feed Pump with TURBOTM

Total Equipment Costs = $33,684Power Consumption = 23 kWEnergy Savings =21.5 kW x $0.10 kW-Hr x 8000 Hr/year = $17,200

Reciprocating Feed Pump - No Energy RecoveryTotal Equipment Costs = $23,000Power Consumption = 44.5 kW

Flow (gpm) Pressure (psi)1 90 302 90 5243 90 9504 90 9305 90 60

TURBOTM Benefits• $17,200 Saved in electricity. ($0.10 kW-hr electricity cost) Payback: 9.5 months• Lower pump maintenance costs and higher reliability due to reduced pump discharge pressure.

HPT-100$13,684

Nm = 92%

Np = 88%

nte = 51%

30 hp TEFC Motor & Recip. Pump$18,000

Flow (gpm) Pressure (psi)1 90 302 90 950

Starter$2000

60 hp TEFC Motor & Recip. Pump$20,000

Starter$3000

Np = 88%Nm = 92%

Figure 8

Figure 9

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STRIPPER

CONTACTOR

LEANAMINE

RICHAMINE

CAPACITY INCREASE BY HIGHER FEED FLOW

In this design option, the objective is to increase the production in an existing plant using the original centrifugal pumpand motor. A TURBOTM will be placed in series with the existing feed pump. The two untis will display a much greaterhydraulic range than the feed pump alone. The increased hydraulic range permits greater amine flow thus allowing theaddition of new contactor and stripper capacity for greater gas throughput.

• Pumping capacity increased 60% using the existing feed pumps andmotors

• Energy consumption per gallon of amine pumped reduced by 60%• Minimized disruption to the existing plant

Areas to be Evaluated

Several areas need evaluation before usingthis approach.

• Contactor and stripper capacity needto be evaluated.

• The NPSHR of the feed pump mustbe satisfied

• Feed piping and headers must handlea higher flow

• Feed pump motor rating must not beexceeded

• Feed pump suitable for highercapacity

In this example, the plant owner wishes to increase thecapacity of the high pressure amine pumping system. Theplant uses a 7 stage centrifugal feed pump. The NPSHRcurve shows that the pump capacity can be increasedfrom the present 500 gpm to 800 gpm without theNPSHA falling below the NPSHR.

Next, the TURBOTM boost is calculated near the 800gpm rate. The combined feed pump - TURBOTM pres-sure is far higher than needed. At this point a decisionneeds to be made; should the TURBOTM be derated toproduce less boost or should the pump be destaged thussaving pumping power.

Assume the owner wishes to save energy as well as in-crease capacity. A combined destaged pump -TURBOTM curve is then drawn based on removing three(3) stages (see Figure 10).

Figure 11

∆ NewCapacity

ContactorPressure

Destaged Pumpwith TurboTM

7 Stage Pump

OriginalCapacity

4 Stage Pump

Figure 10

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INSTALLATIONCharacteristics of the TURBOTM that affectinstallation are described below:

Compact Size and Low Weight

The compact size permits installation invery confined spaces. A unit able to handle100 gpm (23 m3/hr) can be carried in onehand. A unit rated for 1,800 gpm weighs520 lbs.

Flexible Installation

• mountable in any orientation• supportable by the supply piping

(HTC-25 thru HTC-100 only)• locatable anywhere in the system

ANSI raised face flanges are standard.

The TURBOTM does not require shaft align-ments or heavy foundations. Installationusually requires only simple pipe work,only the larger sizes require a modest foun-dation.

Low Noise and Smooth Flow

An operating TURBOTM is usually inau-dible over the noise of the feed pump. TheTURBOTM can reduce overall machinerynoise by virtue of the reduced size of thefeed pump and motor.

The TURBOTM does not generate pressureor flow pulsation in the fluid streams.

Pressurized Discharge

The TURBOTM can discharge the richamine against any level of backpressure.There is never a need for a booster pump.

Other Factors

• Material selection should bebased on specific experience. Standardmaterial for the TURBOTM is alloy 2205steel (a second generation duplex stainlesssteel).• A pressure gage should be in-stalled near the feed inlet to the TURBOTM.Another pressure gage should be installednear the feed outlet of the TURBOTM.These gages permit measurement of the

amine pressure boost to verify normal op-eration.

Two-phase flow

There will be a release of gas as the amineis depressurized within the TURBOTM. TheTURBOTM is designed to handle levels ofentrained gases typical in liquid absorbentsystems.

Requirements

• Discharge pressure pulsationdampeners should always be used withreciprocating feed pumps. The dampenershould be set for proper operation at thedischarge pressure of the feed pump. Also,the dampener should be located betweenthe feed pump discharge and the inlet tothe TURBOTM.• Perform all pipe flushing beforeinstalling the TURBOTM. Debris such aswelding slag or mill scale can cause prema-ture failure of the bearings.

See the PEI Installation and MaintenanceManual for further information and recom-mendations.

Flow Control and Energy Recovery in anAmine Gas Processing Plant UtilizingPositive Displacement Pumps

Many amine systems use positive displace-ment pumps (PD pumps) for the high-pres-sure charge service. Because of the con-stant flow output of theis type of pumpflow control can be achieved in two ways,variable speed drives (VFD) or recircula-tion of flow through a high-pressurethrottle valve back to the pump suction.VFDs have high capital cost and introduceadditonal mantenance requirements andalsthough they save energy at the pump,they donot recover any energy that is con-sumed by the pump motor. Flow recircula-tion requires a relatively costly throttlevalve and has the highest energy consump-tion.

The Turbo offers an elegant solution toPD pump flow control requirements. Asseen in Figure 5 the total PD pump leanamine flow enters the pump side of the

Turbo where it is boosted to contactor pres-sure. To control contactor level, a portionof the flow is diverted through a bypassvalve directly to the rich amine flow fromthe contactor. The merged flow then en-ters the Turbo, therby providing energyrecovery to 100% of the high-pressurepump output.

Flow Control and Energy Recovery in anAmine Gas Processing Plant UtilizingCentrifugal Pumps

When using centrifugal pumps as the high-pressure charge pump, recirculation ofpump flow back to suction is not neces-sary as with PD pump driven systems.However, to control contactor level, thepump discharge is throttled to vary thecapacity of the system. The amount ofdownturn can be significant, which resultsin energy losses by the pump running offdesign in a lower efficeincy range and bypressure lost through the throttle valve.

The use of the Turbo with centrifugal pumpdriven gas processing plants provides theoptimum sulution to flow control and en-ergy recovery. Like with the PD systemthe total flow at the pump duty point (whichshould be a t or near the pump’s Best Effi-ciency Point) enters the pump section ofthe turbo where the flow is boosted tocontactor pressure. Lean amine flow notrequired by the current operating condi-tions of the contactor is diverted throughtthe bypass valve as seen in Figure X to bemerged with the rich amine flow comingfrom the contactor. The merged flow en-ters the turbine section of the Turbo, therbyproviding energy recovery for 100% of thehigh pressure pump flow.

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STARTING AND OPERATION

Response Time

A question occasionally asked about the TURBOTM

is its response time to changes in flows and pressures,especially during startup of the system.

Figure 12 shows the measured pressure duringstartup of a triplex reciprocating power pumpequipped with a model HTC-150 TURBOTM. Notethat the TURBOTM feed discharge pressure lags theinlet pressure by only about 0.1 seconds. This re-sponsiveness insures easy control of the system.

For complete starting and operation data refer tothe PEI Installation and Operation Manual.

System Startup

Since the feed pump is downsized to take advan-tage of the TURBOTM boost, it can not generateenough pressure to establish flow through a fullypressurized contactor.

Since the TURBOTM comes up to speed quickly,simply precharging the contactor with a smallamount of amine before pressurization will provideenough high pressure liquid to develop fullTURBOTM boost.

If the above is not possible, then a bypass line witha valve connecting the TURBOTM lean amine outletto the rich amine inlet can be used to briefly direct highpressure amine to TURBOTM turbine inlet (see figure5). After a few seconds the valve can be closed as thevalve to the contactor is opened.

MAINTENANCE

The Turbo’s bearings are full fluid film lubricated andwill have a long operating life, however rates of wearwill depend on the cleanliness of the liquid. If it be-comes necessary to replace the bearings, an overhaul isa very simple and quick procedure. A turbo overhaulconsists of removing the TURBOTM from the piping,

removing the end cap and pump casing, removing the pumpimpeller and then replacing the rotor and sleeve bearings.An overhaul can be done in one to four hours depending onthe size of the TURBOTM.

The radial bearing is a sleeve type and thrust bearing isa hydrostatic type. The bearings are mounted in O-rings with a “slip fit” with the casing. Removing theold bearings and installing new bearings is a simplemanual procedure.

No LubricationPumpage-lubricated bearings eliminate a range of prob-lems such as contaminated oil, improper maintenanceof oil level, oil seal failure, bearing cooling failure, etc.

No Shaft SealsShaft penetrations to the atmosphere, with the atten-dant shaft seals, don’t exist with the TURBOTM. Shaftseals require periodic maintenance and can catastrophi-cally fail resulting in emergency shutdowns.

Figure 12