ELECTRICAL SUBMERSIBLE PUMP-!HANDBOOK

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SAFETYi Section 1

SWITCHBOARD SAFETY TIPS1.1

LIsted below are several safety tips that should be followed Inaddition to any local safety requirements. When working with

switchboards always remember:IHIGH VOLTAGE CAN KILL!

Stand to the right side of a switchboard when stanlng orstopping a unit. The door can blow open In case ofexplosion.

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I2. If checking high voltages. make sure proper meters and

safety gloves are being used.IAlways check a switchboard for proper grounding.3.

I II unusual or loud noises are coming from a switchboard. calla qualified electrician.

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5. If arcing noises are present, wear proper safety gloves untilsource of arcing Is located and fixed. ,

leave voltages alone If untrained or nervous. Have 8qualified electrician ~heck a switchboard If necessary.

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MONITOIRING AND REPORTING

Monitoring is the key to efficient ESP opera tions. Usted below are

some da1:a to be monitored:..

Dally amp chartsUnusual operating characteris ics

Auid levelsCasing and tubing pressureGauges (tubing & casing)Tear-down reportsCause analyses

IDaily Monitorina

Sufficient records should be kept to allow the engineer or foremanto get an overview of the pump's operation and well performance.Any out of the ordinary operating characteristics should be noted Inthe well's file. Amperage charts should be maintained and used asa daily monitoring procedure (see Trouble Shooting Amp Charts).Seven day or daUy charts should be used. If electronic datagathering systems are used then a hard copy should be keptperiodically so the entire pump life can be examined. Propermaintenance and calibration of the recording devices shouldalso be done. Section 4.2 shows a Standard OpArating Procedureused by Sacroc to monitor well performance.

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I Rangley Shuttle Valve

A second alternative Is the shuttle valve developed InRangely, Colorado. and Is similar to a check valve. The maindlHerence Is when the ESP shuts down, the check valvedrops. preventing "uld !rom flowing through the ESP, andexposes a side opening which allows the tubing 'and annulusto equalize. The side opening will allow chemicals to bepumped down the tubing, but not through the ESP. Whenthe ESP Is restarted the check valve rises and seals the side

opening.

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EQUIPMENT2.3

TI,e ESP system can be divided Into subsurface and surfacecomponents. rhe major downhole components Include an electricmotor. seal section. muill-siage cenlrifugalpump wilh an Intake anddischarge. and power cable. Optional downhole equipment mayIllclude a bottomhole pressure/temperature sensor. check and drainvalves. motor shroud. and a gas separator. The surface componentsillclude a 'unction box. switchboard. and transformers. A typical ESPIllstalialion Is shown in Figure A. A description of each componentI~ given below ,beginning downhole and moving up the well.

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..ISubsur1ace EoulDment

I Motor

ESP motors are two-pole. threEt-phase, squirrel cageInduction motors which operate at fl nominal speed of 3500rpm at 60 Hz. Voltages range from 480 to 4,125 volts, whOeamperages range from 14 to 143 amps. Horsepower IsIncreased by Increasing motor length for a given diameter

size or motor series. Large horsepclwer requirements usuallyrequire two or more motors, commonly referred to as

tandem motors.

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I Molors.. are lilled with a nonconductlve oil with a highdieleclr!c strength which provkJes lubrication lor bearings

and good thermal conductIvity. Produced fluid moving pastthe outside 01 the motor carries heat away; cooling the motor(minimum recommended fluid velocity Is I ft/sec). lIthe fluidveloclty'\s nor sufllclenllo coollhe motor, or if Ihe motor Islocated below the per1orations, 0 shroud should be placed

around'the motor.

Seal~ Pro'ec'or, Equalizer

The seal section (also known a!i a protector or equalizer) Islocated between the motor and lIuld Intake 01 the pump. Theseal sery~s live main junctions: ;"

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eliliained In Ihe cable 10 escape 10 Ihe almOsphE!re beforereaching Ihe switchboard. The junction box also provideseasily accessible test points for electrically checkingdownhole equipment. [fa be used wilh pac.,-off typesubpump hangar. Not necessary with EFT (Electronic FeedThrough) hangar.

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ISwitchboard

Switchboards (motor controllers) consist of a motlor starter,relays for over1oad and under1oad protection, a circuitbreaker, time delay relays, and a recording ammeter. Theswitchboard also features a lIghted display so that a pump's

operating condillon can be seen from a distance.IOverload and underload relays protect the ml)tor trom

drawing excessive amperage and Insufficient simperage,respectively A system does not automatically ~:11f It goesdown on overload. Time delays are used to aliolN enoughtime to pass after a shutdown betore a restart attempt Ismade; the time delay should be long enough to alli)w nuld Inthe tubing to equalize wilh the annular fluid. Time jjelays arealso used with external control devices, such as tank levelcontrols or line pressure switches. Excessive cyciling Is not

recommended due to the high amperage occ:urrlng at

start-up.

The ammeter records the amperage drawn by thel motor ona 24-hour or 7-day amp chart. Amp charts are a vital means01 ESP diagnostics. They give Indications 01 powernuctuations. gas locking, pump-a", false starts, cycling,undercurrent loads, overload, debris, and normal conditions(see Trouble Shooting Amp Charts).

Variable Speed Drive (Optional)

ESPs are relatively Inllexible In their production range whenoperated at a fixed frequency. Variable speed dri'/es (VSOs)allow an operator to vary the frequency. and thus the flowrate, to bener match well conditions. However. '/SOs havehigh Initial and maintenance costs. Most ESP comlpanles rentVSO's lor testing.I

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L.z TREATING (ACID, SCALE)

!!JatinG PartiallY PluGGed ES~

Occasionally, ESPs become partially PlUgged!with scale. wax orasphaltenes. reducing pump performance and i creasing lifting cost.Suggested treating is as tollows. .

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Wax

I Wax can build up in the upper secti nl of the productiontubing as in a rod pump well. These pr blems can often beremedied by hot oiling or hot watering down the tubing ordown the annulus through the pump. he following is a key

point to consider:

Pump hot oil or water down t; ! tubing if possible.

Excessively hot fluids down the nnulus could exceed

the ESP cable temperature ratin .I

I Scale

It well bore scale problems are presen in your field. you will

likely have scale build up in your ESP. Frequently you can

treat the pump for scale by pumping t e recommended acid

tor your type ot scale through the pu p. The following are

some points to consider:

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Try to pump the acid down th; tubing instead of the annulus. This oHers bener co Irol over the treatment

and the acid will nol contact t ,armored cable.

ICorrosion inhibitors can be ad ed to acid treatments

to protect the steel armor a ound the cable. (Becareful! Corrosion inhibitors c r\ cause emulsions that

could be damaging to the for' tion) Not to mention

tormation plugging trom tines eleased from scale.

Asphaltenes

I II you diagnose an asphaltene problem, aromatic solvents(such as xyiene and toluene) must be used to disperse the

asphaltenes. breaking them up so they can be removed.Chemical manufacturers have additives to hellp Improvesolvent penormance. Be sure to ~ ~ the ~~manufacturer ~ Dumolng solven~ to be sure what allectthey will have on elastomers (rubber material) Ilrl the cableand pump.

If asphaltenes are suspected a wlreline knife can be used to

cut material loose In the tubing. This material can be

analyzed. If It proves to be asphaltenes. the propl!r treatmentcan be applied before the pump becomes Irreversibly

plugged.

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Hat all

I If a check valve exists above the ESP, the hot 011 must be

pumped down the annulus. Otherwise, the hot 011 can be

pumped down the tubing. It Is more desirable to IPump downthe tubing In order to prevent exposing the cable to the hotall. Cable may be damaged If the temperature of the 011

exceeds the cable's temperature rating. Good rules of thumb

awe:

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When pumping down the tubing, use two tubingvolumes at 80% to 100% 01 the lormatlon tlemperature.

I When pumping down the annulus, use one and a hall

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Hlot Watering

Th~ procedure lor hot watering Is the same as hot oilingexcept Droduced water is used. The advantage 01 using waterI~i that It holds heat longer than oil, thereby rE!qulrlng lessvolume and lower temperatures.IHot watering wililrequently have better results thiin hot oilingC;oncerns about scaling. corrosion, bacteriel, formationclamage. and emulsion problems can be overcome by usingI

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annular volumes at 80% to 100% of the formation

temperature.

Iappropri"te chemical additives. Rules 01 thumb lor hot

I:atering lare the same as lor hot oiling.

~Cid Selection

t he type of scale present will determine the type of acid

equirecJ. All large acid supply companies will analyze aproouced water sample from the well to predict the type of

S cale present Once the type of acid and corrosion Inhibitorsre selected, the volume and strength of acid required can be

""determined by the quantity of scale present. Good rules of

Ihumb are:

I. U~e a 5% solution 01 appropriate acid with goodc:orrosion inhibition additives.

U~e 2 bbls/ I 000 leel 01 lubing.

Always use a larger volume and weaker solution, rather thant smaller volume and stronger solution, because the bottom

ortlorl 01 the cable and some cable bands will unavoidablycome In contact with the acid. II the acid is weaker the

~orroslve ellects are lessened.

8r,eatlng

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T! The al:idizing procedure lor a seized ESP Involves a linedIfpressllre truck with a lined or nonreactive pump. The acid

shoul(]1 be thoroUGhly mixed orior to pumping down theItubin~11;'~ suggested acid procedure is as lollows:

Rate

(bbls/mln)Description

1 Pump until acid Isabove the ESP. Thefirst '/. tubing volume01 ack1 Is used up, orspent. as It dissolvesscale Irom the tubing

2. Pump the V. tubingvolume 01 spent acidInto the annulus andthe next '/. tubingvolume of acid Intothe ESP.

Volume

11ublngvolume of

acid

I'h tubing

volume ofacid

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3. Allow a 15soak lime10 work.

4. Pump a Iresh,unspent Y. tubingvolume 01 acid Intothe ESP.

y. lubingvolume 01

acid

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5. Let soakapproximately sixhours.

6. Turn on the ESP andproduce the spentacid down theflowline.

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The final Y. tubing volume 01 acid Is not pumped Ihrough theESP because II will be diluted by tile nuid used 10 displaceIhe acid (usually waler)

Acldlzlng Asphaltenes

Asphaltic crudes are sensitive to the presence ollerric iron

during acidizing operations. The iron acts to crosslink the

asphallene molecules, lormlng added.oil sludges. Iron

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minutelor the acid

I Treallng

The asphaltene removal procedure lor a seized ESP Involvesa pressure truck with a pump containing tenon seals. Thesolvent Is thoroughly mixed prior to pumping It Is then

pumped down the tubing A typical asphallene removalprogram is as follows:

Description Volume RIle(bbls/mln)

1 1 tubing

volume 01

solvent

1Pump untH solvent Isabove the ESP. Thefirst Yo tubing volume of

solvent Is used up, or

spent, as it removes

asphaltene from the

tubing

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I ~ tubingvolume 01

solvent

~2. Pump the Y. tubingvolume 01 spent solventInto the annulus and thenext Y. tubing volume 01solvent Into the ESP.I

3. Allow a 15 minute soaklime lor the solvenl towork.I

-4 Pump a fresh, unspentV. tubing volume ofscjvent Into the ESP.

'I. tubingvolume of

solvent

!-iI5. Let soak approximately

six hours.

6. Turn on the ESP andproduce the spentsolvent down thenowtine.

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sequestering agents are IneHective at preventing ackt-oUsludging since the sludges are formed before thesequestering agents function. These sludges can best becontrolled by a prenush of aromatic solvent/asphaltenedispersant which removes any existing asphaltene depositsplus acts as a spacer between the acid and oil. The aromaticwill also clean the tubing and ESP. Improving theeHectiveness of the acid.

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Most miscible flooding operalions will have asphallene

deposition In the well during Initial stages 01 gasbreakthrough. A good rule 01 thumb lor treatment volumesIs 1 bbl/IOOO leet ollubing 01 aromatic solvent/asphallene

dispersant as a preflush to the acid.

Solvent-Rubber Reaction

Solvent Is usually pumped down the tubing and rarely downthe annulus. II solvent Is pumped down the annulus at lullstrength, h will come in contact with the cable and destroy

the Integrity 01 Its nuld jacket. Most fluid jackets arenltr~e-based and most solvents will swell nitrite 25 '0 50%. II

this happens the cable armor may burst and/or an electricalshort will occur.

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ICheck with the ESP manufacturer before pumping any

solvents through an ESP. Some manufacturers use nitritebushings in the pump. and these will swell and seize the ESPif they are contacted by a solvent.

Solvent Selection

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The Iwo most common and eHective aromatic solvents arexytene and toluene. Both are equally eHectlve at repetizingasphaltenes. The various chemical manufacturers havesur1actants and dispersants which will Improve the perfor-mance 01 these aromatic solvents. Chemical companies willtest a sample 01 asphaltene and determine which Is the bestlormula lor the sample given. This Is usually done quickly,but the testing Is extremely biased. For complete. unbiasedtesting, send a sample to COFRC. The testing time Is longerbut the recommendations will be nonbiased.

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The volume of solvent will be determined by the quantity of

asphallene present. A good rule of thumb Is IIC) use 2bbls/ I 000 feel of tubing.

II the tubing or ESP Is plugged solkj and pumping clown the

tubing Is impossible, a coiled tubing unit can be used toclear the plug In the tubing and/or squeeze solvent throughthe ESP Plugging can be avoided by implemer1tlng the

monitoring program described below.

Aeduclna Treatment CQl1J

ICheck Valve VI. No Check Valve

Check valves are Ihe mosl common melhod of prevenllngnuid from passing Ihrough Ihe pump. The advanlages areIhal check val\/es are inexpensive. prevenl sand or particlesIn Ihe fluid fr,Qm plugging pump during shuldown.' allowImmediale reslarting, and Immedlale producllon upon reslart-Ing. The major dlsadvanlage is Ihat check valves do norallow clrculallon down Ihe tubing; reverse circulating downIhe annulus can be done inslead.

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Back Spin Relay

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PUMP OFF

~roblems.Unit 100 large

Solutions.Redesign syslem with smaller pump (currenl syslem 100 large).Stimulate well

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FALSE STARTS

Problem~.Auto restart delay not of sufficient lenglh to allow adequate

fluid build-up.

SolutIOQ~.Increase restart delay

.Redesign ESP

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Transformers

Transformers are used to convert primary line volta'ge tomotor voltage requirements. Three types of transformers usedIn conjunction with ESPs are: banks 01 three single-phase

transformers. three-phase sta~ard transformers. arKithree-phase auto transformers. The transformers are oill-filledand self-cooling. For oHshore platiorms where oil-filledtransformers might be prohibited. dry type transformelrs areavailable. The transformers are equipped with taps to providemaximum flexibility In voltage outPut.

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TROUBLE SHOOTINGSection 3

3.1 TROUBLE SHOOTING GENERAL

Check the switchboard's indicator lights 10 see it ihe unit isrunning If down. check to see it it is down due 10 IJnder1oad

or over1oad. :1

Check the amp chart 10 see if any unusual lines or blips arepresent. For help in Inlerpreling amp charts see TroubleShoaling Amp Charts.

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3. Check Ihe murphy switch or the eX1ernal switches 10 see IiIhey are coni rolling the switchboard.

4. II down due 10 an over1oad condition, call an electrician tocheck lor a shan downhole before anempting to reslan.

5. Check primary fuses to see If they are open. These Ituses willopen when there is a surge of power on one leg.

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6. Visually inspect transformer hookups.

7 Insure the electrician checks the unit downhole I:rom thelowest point of connection.

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Problem #2: Unil shuls down due to undercurrent.

Possible Causes Possible Corrective Actlcinl

Low well productivity -

pumped-oN condition.Check amperage downhole

.Shoot fluid level. Pump water down

backside II no fluid levElllsavailable. \I there Is lIullj In the

well, consider pump ctllange.I

IPlugging of pump Intake .Check to see if pump Is pumping

fluid.

.Pump acid down tubin!) andthrough pump II tubing Is open topump discharge. (see 13ectlon 2,Treating)

.Pump acid down backside andspot around pump Intake.

I .Change out pump. Have the pumpackilzed and tested beliore sendinglor repair. This may avoid the

unnecessary cost of repairing ascaled pump.I

Underioad set too high .Check amperage dowrlhole on allthree phases and comlpare with

nameplate amperage 01 motor.Reset under1oad lilt Is above 80%01 nameplate amperage. Do nol gobelow 60% 01 molar arnperage.

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Broken shah In unit

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.Compare downhole amperage withIdle load amperage (typically45-55% 01 nameplate amps).Reverse unit In switchboard bychanging two downhole leads.

Check amps again; they should bewithin :t 10% of lirst reading.Reverse leads again. Pump water

down backside if available. Start

unit again. " amperage Is constantthrough this procedure. a brokenshaft exists and the unit must be

pulled.

.Pump water down backside tobreak gas lock.

~Pump

Is gas locked

.Vent casing to flowline II possible

.Check setting depth to see if unit

can be lowered closer to

perforations.

.Install shroud or gas separator.

.Check pressure control circuit or

other auxiliary that could cause

shutdown.

Faulty remole conlrols 10

switchboard

.Check all valves to make sure the',are open. Check pressure onwellhead and lIowline. Check tosee it pu~p is pumping fluid.

Flowline restrictions

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8rOb'em #51: Unit will not restart atter underload shutdown.

[prOblem #6: Unit will not shut down with HOA switch. =

II Possible Causes Possible Corrective Actions

C II Control relay stuck

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I Problem #7: Unit will not shut down by underload or overlclad.

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Possible Cause. Possible Corrective Ac:tlonl

Undercurrent shutdown .Check downhole arTlperage. II

~or~al~ust setting.Remote controls haveopened and shut unitdown

.Check for open or closed contactson remote circuits and clean or

repair as necessary.

Unit starts but shuts downwithIn 5 seconds

.Check remote contclcts and cleanor repair as neces~lry.I

.Check lor correct phasing oncontrol power Irans10rmer.Change II necessarf.I

.Check CT phasing. Change 3.5.710 controller If necessary.

Unit will not tlme-olf .Check remote circuits. Unll will nolslart In lime-oil II relmole contactsare open.I

.Underload Is set too low. "underload Is set pa,st the lowest

se"lng mark, timer sequence Is not

operational. Check CT ratio 8~adjust underload as needed.

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I FIGURE A

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4

5.

Connects the drive shalt of the motor directly to the

pump shattoAbsorbs the axial thrust from the pump.Protects the motor oil from contaminalion by the wellfluid.Allows pressure equalization between Ihe well annuluspressure and the molar internal pressure.Provides a reservoir for volume changes as the motoroil heats up and cools down.

I Seals contain a labyrinth chamber with a blacking fluidbetween the well fluid and motor ail. The blocking fluid iscommonly the same ail used In the motor. It may also be ahigh density fluid for special applications. Seals may alsocontain a positive elastomeric barrier, or BAG. In combinationwith a labyrinth chamber. Several operators have Increasedrun lives using tandem seal sections as an added means of

protection.

~Ie~~Gas Separators (optional)

Gas reduces the efficiency of ESPs; therefore. gas separatorsmay be Installed between the seal and pump to reduce theamount of tree gas entering the pump. Both reverse flow androtary separators are available with the latter being moreefficient at gas separation. Some operators run tandem gasseparators In high GaR wells 10 more effectively remove gastrom the pump intake. Gas separators QQ !:!Q! handle

significant volumes of free gas efficiently.

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Pump

The submersible pump Is a multi-stage centrifugal pump;each stage consisting ot a rotating Impeller and a stationarydiffuser, that produces a given amount ot head for a givenvolume. Impeilers may be either floatinq or fixed. Aoatingimoellers, which are the most common, move axially alongthe shaft and are tree-floating when the pump is operatingwithin the recommended capacity range (see Figure B).However. jf the pump is operating ~ (to the left of) therecommended capacity ~, the impeller will be in adownthrust condilloQ. Conversely. if the pump is operating~ (to the right of) the recommended capaCity~ the

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impeller will be in an u~Ihrust condition Both downthrust andupthrust can cause excessive wear and can be detrimentalto the pump.

f:lxed Impeller.

I Fixed Impellers are directly connected 10 the pump shalt and

cannot move axially. Allhough this saves impeller and diHuserwear. fIxed Impellers may allow lor a high axial thrust to bedeveloped which must be absorbed by the thrust bearing In

the seal.I

Impellers are classified as either radial flow or mixed flowtype. For 8 given diameter pump. radial flow Impellers will

have higher head pressure but slightly lower rate capacity

than mixed now Impellers.

Impellers may be made 01 dl"erent materials. The mostcommon is a melal alloy called NI-Resist which Is composedmainly 01 iron and nickel. Other Impellers are made 01 aplasllc called Ryton. Ryton Is advantageous in scaly orcorrosive envlronmenls since scale does not lorm on theRyton. and since corrosion does not affect plastic. NI-ReslstIs belter for deep wells, high temperatures. and abrasive

fluids.

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Check and Drain Valve. (Optional Equipment)

A check valve, located two to three joints above the pump;prevents the pump trom rotating In the reverse directionwhen the unit shuts down. This reverse rotation occurs whenthe fluid In the tubing tails back aher the unit has stopped.An attempt to start the system while the pump Is rotatingbackward could result In a twisted shalt. The check valve, ifnot plugged open by debris, will keep the fluid trom tailing,

thus protecting the pump trom reverse rotation.

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IA drain valve, located one loint above the check valve.prevents pulling a wet tubing string. Drain valves also allowcirculation ollhe wall when a check valve is run. Drain valvesare not required unless a check valve Is used.

Power Cable

Electric cable strapped to the tubing Supplies power from the

switchboard to the motor. The cable Is made up of three

copper conductors. either solid or mullistrand Theconductors are Individually Insulated: various Insulallons areavailable depending on well fluids, temperature. andpressure. A jacket material surrounds the Ins~atedconductors for protection against mechanical damage andthe environment. A metal armor Is wrapped around the/acketlor further protection against mechanical damage. The metalarmor also helps prevent swelling when gas or liquid

permeates the jacket material at high pressures.

Cables are available In round or "at configurations a~ Invarious sizes. Flat cables are used where clearance betweenthe unh and casing Is small The most common conductor

sizes are No.1 (largest), No.2, No.4, and No.6 (smallest).General amperage ratings for the diHerent cable sizes are:

#8 -up to 37 Imps#4 -38-57 Imp.#2 .58-65 amps#1 -66+ amps

I As B general rule. voltage drop within the Installed length of

cable, corrected for boltomhole temperature. should notexceed 30v /1000 It.

I Motor Flat Cable

A motor "at cable, connected 10 the lop 01 the motor, Is runalong the length 01 the ESP syslem and spliced Into the mainpower cable lust above Ihe pump. The molar fiat Is necessarydue to the lack 01 clearance belween the ESP and casing

Sul1ace Eaulcmenl

Junction Box

I A vented junction box is located between the wellhead arid

switchboard. In high pressure wells, gas may permeate tilecable and migrate to the surlace. The 'unction box allows gas

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+ -ANA L Y Z E PBQ~L -.EMI Section 4

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EQUIPMENT TESTING

I When ESP equipment Is pulled from a well its disposition may varyi from running h back Into a well, to sending it to the manufacturer toi be rebuilt, to having h tested by a manufacturer or testing company.

I lf the equipment was pulled for some reason other than a failure, a, well site Inspection may be adequate to determine whether it Is

suitable lor rerunning. However, if the equipment Is not going to bererun Immediately, or If there is doubt as to hs condition, It is

I recommended that it be tested. Testing Is an Inexpensive means ofdetermining the condition of used equipment. In the motor testing

program, expensive repair costs can also be reduced as much asI 90%. Sending equipment to be tested Is of particular Importance

when equipment has been subjected to a hostile well environment(high water cut, COl, HJS, etc.). The cleaning of equipment and

I preparation for storage that Is Included In the testing procedure, is asImportant. if not more so, than the testing Itself. Pumps. in particular.left stored on the rack without flushing can "lock down. and become

Inoperable.

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PumR Tesllng

Each section 01 a pump should be Inspected lor problems,such as a twisted shah, hole in the housing, or any problemthat would require h to be sent lor repairs rather than testing.

2. The pump should be steam cleaned Inside and out 10 removeparaffin and well fluids. Olher chemical washes are alsoavaUable 10 remove sulfate scale. gyP. paraffins. and

asphaltenes.

3 HCL containing an Inhibitor and dispersant should be

pumped through the pump lor a minimum 01 two hours. orunlU acid reaction Is complete. if scale is present.

4 The pump should be flushed with clear water prior 10 lesli"g.

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8.

9.

Molar Testlo.g

a. Check the phase-la-phase (lead-to-lead) resistance IIshould be balanced among all leads.

b. Check the phase-to-ground (lead-to-housing)

resistance. Typically, h should be more than 2000

megohms on a megohm meter with no pressuredevice.

c.

.IROUBlE ~HOOTlt~G AMMETER CHARTS

rnalyzing ammeler charts Is one of Ihe best ways to diagnose a.~ulllber of problems. LIsted on the next few pages are examples of

ammeter charts lor various operating conditions. These charts arereprinted from the .Submerslble Pump Handbook" with permission

Ilroin Centrilift.

Comparing these amp charts to your amp chart may give anB Indication 01 the type 01 problem you have.

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I NORMAL.Under normal conditions the ammeter should draw a smooth

symmetrical curve near nameplate current. S'plkes at start-up

are normal.

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POWER FLUCTUATIONSProblems.Fluctuation of Primary Power Supply (Start-up of large HP

motors Injection pumps etc.)

SolU1lons.Investigate Power Fluctuations.10 causes 01 fluctuations (Start-up of larget HP mott

Injection pumps).Call power company

-::°. ' "

Cle~n molor

Sleam clean body to within one foot of motor head.

Do not steam head.I a

Solvent wash molor head and lill valve areasb.

T"8 nXltor oil should be drained and checked lor bronze content

(Indicator 01 bearing wear), water content:,varnish/epoxy content, and melled babbit contenl (silver In oil'l.

All boll holes and pothead cap a.rings should be checked lor

damage. The lead washers on Iill valves should always tie

replaced. The motor should be lIushed Irom top down while

qurning rotor stack occasionally. Check oil during Ilush lor

obvious Indicators 01 nXltor problems. Flush the oil unit the

discharge is clear. Dielectric strength 01 the 011 should be atlealst

25KV. Once Ilush Is co~lete, cap nXltorwhile It Is still lull 01 oil.

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~The P .1. lleakage) oflhe molar should be calculated and havea grealer value than 2.0. The hi-pot lesl should be run al a'

vollage which can be calculaled by the following equalion:(NPV) x 1.5 + 1.7. (NPV) = Narneplale Voltage) ,:

t:O.II' .",r~r.;.,,.''tI;

The phase-to-ground megohms trom the hi-pot test should be

greater than 5,000 megohms.

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17 The spin test Is per1ormed by running the motor at NamePlate Voltage until the temperature reaches 100°F. The motorthen coasts down alter running. Coast time should be smoothand last 6 to 8 seconds. Spin testing should be per1orl1nedtor both the clockwise and counterclockwise directions.I ,

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I ., \I \he motor does no\ mee\ \he above cri\eria, it c'Duld i

) possibly be salvaged by sending it \hrough a "mini dryIDu\." fThis procedure Involves placing \he mo\or in an Insulated ~

~ compartment and applying DC current to the stator until the :1 lJ tempera\ure reaches 250°F. While the motor Is cooling it Is ~.~~i(~!!~~j~l~i~;i~.~;~. --" ::~\;~::;r.\:~. :..:.~ ;;;.1.!~~1-:~":=~.:1

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purged with nitrogen After the dryout. the motor is retestedas previously described. Replacement 01 the motor Insulationblock In the terminal head Is recommended as part 01 any"mllli dryou.".

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~I 2 STANDARD DOE RATING ORDCEDURE

11h' loll~,", lo,m' w", g,o",'ed hV , SACROC O",II'V A,"oo

T"m "","",o"V""d'05AC'OC"""5"oo"dOO""""O""d,,' 10' d"',rno, '00 ,ed""o,", ,"hm,""" o"mp'

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IGAS LOCKING

~.Lowering fluid 'e~el

.Gas e~oI~es In pump

.S-Q!Y1!~.Lower pump.Choke production back

.Put on \imer

.Redesign pump

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WORKOVER AJrnFlClAL UFT SELECll0Nn.ta Sheet. Inltl.1 ~uipment Selection

w. rn-wo nul. unit

D n. c.lia, PnllUrt ..Comm..u

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(F't

v. Commt8U: 8~, 1111 m8pr roalldtnllt081 lor ~alpmtDIItI«kd:

VI. W.. tqUlpm'8' fWlllb. 18m. ..orillD811, mlled for! (YIN!If 80, II" brirf r'pl.a8uoD:

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Do.. WO c..pIoW:

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WORKOVER DATA

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VII. Poll Workower Tell 0818

CO1~GVBW80D4TE

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VIII. POll Work ower fluid lAwell

CASINGPRESS.

fllnDu:vEl COMMENTSDAn:

IX. Resl" Dall

Equip.RUD

Equip.Pulled osRUIODDale

Up/D-Up/D..Up/D..Up/D..Up/D..

X. Comments:

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"I DESIGN! "-

Capital and operating costs, well conditions, reservoirperlormance, equipment and service performance. and ease of

..opera~ing and maintaining the equipment are key considerations'e when designing an ESP.

I An IBM PC computer program called ESPO (Electric SubmersiblePump Optimization' is available from COFRC for ESP design.ESPO selects the most economic system for each manufacturerconsidering both capital cost and power cost. Although computer

I programs make the technical task of ESP design easier. theyshould not preclude your engineering judgement and experience.Contact W. H. (Bill' Ford at COFRC for more information about

-ESPO, or to obtain a copy of the program.

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DECISION At~AL YSIS ECONOMICS

Decision analysis can help you make Ihe best economic artificial lift

decision. Merek. whict! utilizes many lools of decision analysis. Is agood program to base your economic decisions.

TI19 foundation 01 good decisions Is historical data.

go~ recordslPlease keep

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I P UL 1Jl':/J G A~ T ABI: UPSsction 6

IINSTALLATION/PULLING PROCEDURES

Pre-Job Checklist

listed In this section are tips that will hopefully lead to fewer failures.For complete running and pulling directions please consult API RPIIR.

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Eaulcment ReQuired Ogtlonal EglliPJillll!'. Motor .Gas Separator

.Seal Section .Check Valve.Pump .Drain Sub.Cable Motor Flat .Motor Shroud.Switchboard .Variable Speed Driver.Round Power Cable.Junction Box

.Transformers.ESP Tubing Hanger with Tubing Head.Tubing PUP (2'-6')

Services Required

.Cable Reel (54" or larger!

.Cable Bands and Bander (Hand band with precut bandsor power band with reel 01 stainless steel bands!

.Electrician (lor disconnecting and connecting ESP andtestIng cable!

" Subpump SeNlce Technician (on 10catlof1lor length 01lob) !

.Chevron Representative (coordinale Iplacement 01equipment, timing 01 deliveries. and supeNislon 01 theinstallation!.

00 NOT RUSH. Preolannina is an investment for success.IWellbore PregaraliQn

Run a bit and positive scraper set to drih diameter at least100 leet below nllmn !;Rnlnn npnlh A ~Ip~n ntillrin t)plnw IhA

bottom perforation Is recommended If cost ellectlve. Note

any past and present "tIght spots.,

Eaulcment Handling

When unloading ESP equipment, use a spreader bar with achain allached near each end of the box. Never pick-up Inthe middle!

If the equipment Is dropped. damaged. or appears already

damaged. II should be checked by the service technician onlocation.

Note: Slightly more than 50% of III ESP failures InChevron Ire cable failures, so speclll care must betaken In handling the cable.

Never pick the cable reel up by the cable.

Never let any load be placed on the cable during loading,unloading, or storing.

Any rotation of the cable will cause damage.

~gJRunnlna Eaulomeot

Hold a safely meeting 10 discuss the scope of work 10 be

performed. Note any special problems or concerns.

Suggested personnel on location:

-2 Roor Hands

-Derrick Man1 Operator

-2 Cable Reelers (if by hand)

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1 Service Technician

1 Chevron Supervisor

Handle equipmenl as recommended by the subpumptechnician.

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Clble ReellnQ/BandinglRunnlng

Reeling

Reel size should be 54" or larger.1

2.

Reel should be located 75-100' 'rom service rig.

Cable guide on rig should be no more than 30' above

ground.

3.'

4. Always have slack between the cable reel and guidewheel.

5. Always have the cable reel In the operator's line 01

sight.

6. Use cable stands to prevent cable from draggingthrough the dirt.

Banding

It Is very Important that the cable be run straight upthe tubing.

2. Band squarely across the cable. Tubing band shouldbe at right angles to the tubing with the cable vertical.

3. Band flat cable and flat guards straight up the side ofthe seal sectlof11 and pump. Start Immediately abovethe pothead with a section of flat guard which has thebonom end slightly tapered. Continue with the flatguard to lust below the "at cable-round cable splice.

4. Stainless steel bands are recommended (025 x .75(31655)) as minimum. Where conditions warrant (holedeviations. doglegs. scale. etc..) larger bands (.035 X1 25 (31655)) should be used.

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5.

Cable band should slightly deform cable armor. A

power bander should use about 125 psla.

6. Install two bands per 30' loint; one midway on thelolnt. and the other 18" above the collar. If using leadsheathed power cable, additional bands may berequired In consideration of the cable weIght.

7, STOP and contact a service technician if the cable Is

damaged.

8. Extra care should be laken In runnIng cable Inlo a wellwhere an ESP has nol been Installed before.

Splices

IWell conditions and field experience will dictate what type 01

splice Is appropriate. Good splices are the key to reducingcable related failure. Quality control of the splicing

procedures and materials determine the success of splice.The person making the splice has the greatest Innuence overIt. Cleaniness of the tapes, cables. and the splicer's hands Isa must. Tapes if used. must be smoothly wrapped and tight.The cable and conductors should not be manhandled or

sharply bent during the splicing procedure. The lob shouldnot be rushed because the care and time taken here wUI be

recovered In longer run times lor your systems. Specific

procedures and recommendatIons can be obtained from theRangely oHlce.

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IRunning/Pulling Cable

1 QQ1!Ql apply tension to the cable. This could elongatethe cable and destroy the protective Insulation Avoidsharp edges and rubbing 01 the cable during runningQQ.!!Q! allow the tubing to rotate.

'"1I II!

I 2 Clleck cable and molar every 2000' going in the hole(ulecllical conlinuilY and j'lsulalion resistance checks).

I Check \he cable visually and electrically coming out 01IIle hole.

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STOP and have a service technician Inspect the cableIf the cable Is broken, or the Insulation or armor isdamaged (Remember: most cable fallurea reaultfrom mishandling.) (Note depth of damage to cable)

4

I Keep slips In good condition with sharp dies ofnon-rotating type Be sure the swivel lock on the hook

Is latched and that the hook Is not free to swivel-

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6. Run and pull pump between 1000' and 2000' per hourNever pull the cable 'rom tile reel.

7 All slops and slarts should be as smoolh as possi~e.

Always use lihlng subs lor raising or lowering ESP

equipment.I B.

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START-UP PROCEDURES62

Load tubing before slart-up if possible.

Install proper amp cllart2.

I 3 Set overload amperage at 110-120 percent of motor

nameplate amperage.

Sel underload amperage al 80 percenl 01 running amps.4.

Set time delay for a minimum 01 30 minutes.5.

6. Check all valves between the wellhead and lank battery toInsure they are In their proper position.

7. Set the seleclor 5wilch to the "Hand" or "Auto" posilion andstart the pump.

8.

If pump falls to start, consult a service technician orelectrician.I

9. Make sure the load voltage Is within 10 percent 01 therequired surface voltage.

10. Once the amps have stabilized after start-up do the following:

a.

b.

c.d.8.

Observe the ammeter and flowline pressure during

start-up. Low amperage and long pump-up time mightIndicate reverse rotation.Insure that the restart time delay Is set for a minimumof 30 minutes.Install pressure gauge in tree and record pressure.Send 8 record of equipment to the well file.Check amp charts frequently and turn used charts Into supervisors when charts are changed.I

11, Use 24-hour charts for first three days alter ESP Installation(may go to 7 -day charts alter).

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GASSYProblems.Gas Is being produced through the pumpSolutions.Lower pump (use shroud if pump lower than lowest peri).Install gas separator

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EXCESSIVE CYCUNG

PrQblem~.Detrimental to ESP motors.Too large a Unit.Plugged TBG.Tubing leakSolutions.Obtain a nuid level alter shut-down.Check lor high TBG pressure -

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UNDERCURRENT lOADP.!.g~.No /luki In hole.Failure of timing relay

~~.Lower Undercurrent settings (by ESP specialist).Remedial ackJ.

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UNDER CURRENT BELOW NO LOAD

Problem~.Unit oversized

.Under current set below Idle amperage

Actions.Shut well In

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ICONTROLSEroblems.Controlled shut down

(By tank level, elc)

~.Set auto start delay timer above thirty minutes.Use HOA switch to delay start.Check controls

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OVERLOADProblems.Increase In nuld viscosity. sand production, emulsions. or

mechanical problems (lightning), motor overheat or worn

equipment~ctions.Have electrician check out unit

.Do not restartI

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I DEBRIS

Proble~.Debris (scale, sand, muds)

SolutlQll~.Use clean workover lIuids.Clean well prior to ESP installation.See treating

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IEXCESS RESTARTSProblems.Power problemsSolulions.Have unit ctlecked out by an electrician

.Do not restart

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ERRATICProblems.Mechanlcallallure (locked pump. burn motor. blown fuses)

.Change In suriace pressures.Change In specific gravitySolutions.Do not restar1 until unit Is checked out.

--he lollowing tWo pages are Ilow chans generated by Chevron's

~angeIY, Colorado oHice to help in trouble shoaling.

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