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Copyright Rike Service, Inc., 2007 1
Submersible Pump Major Components
Copyright Rike Service, Inc., 2007 2
Copyright Rike Service, Inc., 2007 3
Transformer Bank
One or more transformers providing proper surface power
Copyright Rike Service, Inc., 2007 4
Motor Controller
One motor control panel housing the necessary switchgear and surface controls necessary for operation
Copyright Rike Service, Inc., 2007 5
Length of three-conductor special power transmission cable to link power from switchboard to motor
Copyright Rike Service, Inc., 2007 6
Motor
One or more (in tandem) electrical submersible three-phase two-pole constant speed induction motors
Copyright Rike Service, Inc., 2007 7
Seal Section
One motor to pump-bore fluid isolation section
Copyright Rike Service, Inc., 2007 8
Pump
One or more (in tandem) submersible centrifugal pumps
Copyright Rike Service, Inc., 2007 9
Submersible Lift Components
Copyright Rike Service, Inc., 2007 10
Typical Pump Stage
Copyright Rike Service, Inc., 2007 11
Pump Stages
Rotating Impeller
Fluid enters at eye near hub
Thrown into diffuser at impeller periphery
Pad where impeller rides on top of diffuser
Hub connects stages together
Copyright Rike Service, Inc., 2007 12
Pump Stages
Diffuser (Stationery)
Brings fluid back to eye of next stage
Provides bore for the impeller hubs
Pumped fluid provides lubrication, impeller to diffuser
Copyright Rike Service, Inc., 2007 13
Pump StagesImpeller is pressure balanced at peak efficiency
Overload causes upthrust wear
Underload causes downthrust wear
Usually can operate at 75% to 125% of peak successfully
Volume proportional to speed (usually 3475 RPM)
Copyright Rike Service, Inc., 2007 14
Pump Stages
Head/stage in ft =
U2 (velocity at periphery, fps)2g (gravity constant)
Head is independent of fluid density
Output press = H x S x 0.433
Copyright Rike Service, Inc., 2007 15
Pump Stages
Stages added in series to provide required head
Head must cover vertical lift, friction pressure, and surface back pressure
Volumes of 20 BPD to 25,000 BPD and higher
Copyright Rike Service, Inc., 2007 16
Pump Stages
Sizing must be correct
Over or under capacity shortens thrust bearing life
Pumping off causes cable or motor failure due to heat
Copyright Rike Service, Inc., 2007 17
Motor
Two pole, three phase, squirrel cage, induction type
3475 RPM on 60 Hertz 230 to 5,000 volts 12 to 110 amps Not synchronous, slip
increases with load only slightly
Efficiency, 80% to 90%
Copyright Rike Service, Inc., 2007 18
Motor
Cooled by passage of produced fluid by external case
Requires velocity of about 1 fps
Viscosity and density changes can affect cooling
Copyright Rike Service, Inc., 2007 19
MotorPressure balanced to the well fluids Lubricating oil inside motor Isolation achieved with
dense lubricant at bottom of U-tube
Well fluids contact dense lubricant on one side of U-tube
Provides for expansion of lubricant when hot
Copyright Rike Service, Inc., 2007 20
Motor
Sized in 4" to 7" diameter
BHP = Q x H x Sp. Gr.
Eff. x 3960
Copyright Rike Service, Inc., 2007 21
Protector or Seal Section Connects pump to motor,
both outer housing and drive shaft
Houses the pump thrust bearing
Seals power end of motor housing from wellbore fluids and provides pressure balance or communication
Provides volume necessary for oil expansion at operating temperature
Copyright Rike Service, Inc., 2007 22
Protector or Seal Section:Important Requirements
Clearance in the casing to allow flat cable operating temperature
All thrust load must be transmitted to thrust bearing
Thrust bearing requires good alignment
Oil viscosity very important to thrust bearing life
Vibration and misalignment will destroy oil film
Copyright Rike Service, Inc., 2007 23
Cable Characteristics
Copper or Aluminum Round stranded cable in
major portion Flat cable where clearances
are small Resistance drops voltage
according to length
Copyright Rike Service, Inc., 2007 24
Sizing Cable
Chosen for current carrying ablity: Example, No. 1 Cu carries up to 110 amp
Ohms per 1,000 ft. indicates voltage drop, E = 1R
Insulation indicative of voltage service available
Voltage drop/Amp/1,000 ft. range: 0.3 to 4.0 +
Copyright Rike Service, Inc., 2007 25
Insulation and Armor
Temperature seriously affects some insulation
Armor affected by abrasion and corrosive fluids
Some operators attribute more than half of submersible pump problems to the cable
Copyright Rike Service, Inc., 2007 26
Key Components of Controller
Motor StarterOverload Breaker (fast acting)
Need only ½ second forhigh current start up
Copyright Rike Service, Inc., 2007 27
Key Components of Controller
Underload Breaker Important because of need
for cooling motor Usually has automatic restart
Copyright Rike Service, Inc., 2007 28
Key Components of Controller
Manual disconnect Time delayRecording ammeter
(important diagnostic tool) Fuses for short circuit
protection (fast acting) Sometimes includes surface
read out of BHP and BHT
Copyright Rike Service, Inc., 2007 29
Key Components of Controller
External Controls Tank hi-lo switches Line pressure switch
Copyright Rike Service, Inc., 2007 30
Key Components of Controller
Good settings and proper maintenance of controls are often the key to successful or unsuccessful operation