• Author / Uploaded
• Carlos Valdivieso

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Example 7

FloSystem User Course

ESP Design and Analysis

ESP Design and Analysis Modes Design Mode 

Entering a Setting depth, max. OD, Op. frequency, Wear factors and Efficiency.



A selection of the Pump/Motor is made



Selection is made from a internal database of five manufacturer’s data

Analysis Mode 

The Pump/Motor (ESP) has been selected



Performance of the ESP can be analysed running sensitivities : 

Pump variables e.g. Operating Frequency



Reservoir parameters e.g. Water cut

ESP Design Mode 

Open ESP.WFL - Review Reservoir, Deviation, and Equipment Data



The completion string contains an ESP at the bottom of the tubing (i.e. 14632 ft)



Select ‘Data Preparation - ESP Data...’



Revise the ‘Pump Environment’ box : 

Note the Measured depth is the pump depth



OD and ID are chosen considering the casing ID



Operating frequency is a typical value



Upstream temperature used only in manual mode calculations (leave as default)

ESP Data... : Design Mode only

ESP Data... : Design Mode only 

Revise the values of Wear factors/Efficiency box  Note

the wear factor are set to 1 for the pump and motor (i.e. no wear assumed)  The efficiency of the gas separator is 100% i.e. no free gas through the pump 

Revise the Calculations options box  The



viscosity and gassiness are switched on

The Analysis equipment box can not be edited in this mode

ESP Design... :

ESP Design Rate : Liq. = 450 stb/day 

Select ‘Analysis - Operating Point...’



Select Calculate, Results and Plot



Note Operating Pressure = 3547 psia and Liquid rate = 110 stb/day (very low for this well)



Select Analysis - Pressure Drop





select Edit Rates... and set the design rate of 450 stb/day. Select calculate, results and plot



note that the pressure at pump depth is 3226 psia

Select ‘Analysis - ESP Design...’ 

Note the Design liquid rate is set at 450 stb/day



Verify with Choose ESP... that the list is empty



Revise the Correlations... options

ESP Design... Box 

Select Calculate and then Choose ESP...

ESP Design: Choose Pump 





Revise the suitable list of Pump - Motor Choose Pump T4-500, motor T5 Series from manufacturer ESP Inc. and Cable #2 Select Plot to obtain the ESP performance

ESP Pump Performance

ESP Optimisation Pump Performance 

Select Optimise... to optimise the configuration in terms of  Frequency,  Number

of stages or  Three performance criteria (minimum, maximum flowrate, or most efficient operating Cable sizepoint) power losses will be included in the Electrical Power results

ESP Optimisation Pump Performance 





Frequency: design calculations repeated to obtain optimum number of stages and flowrate Number of Stages: the new operating frequency is estimated by reiteration (equations not shown) Performance: the operating frequency and number of stages are computed by iteration such that the operating rate (P and T from mid-point of pump depth) corresponds to the minimum, maximum or best efficiency value

ESP Optimisation Pump Performance 

As exercise optimise using the following parameters:   



70 Hz reduce the number of stages to 103 change the performance to best efficiency

Review the impact of these changes on other design parameters

ESP Design Install...

ESP Analysis Mode 



 

Note that the switch ‘Design mode only’ is switched off indicating that the ‘Analysis mode’ is on The Analysis equipment box is now editable and displays the pump and motor parameters installed Select OK if satisfied with pump selected. Select Analysis - Operating Point (Edit rates Fill)  Note

that the new Operating Pressure is 3240

ESP Analysis

ESP Analysis: Sensitivity Studies 



Once optimum parameters: Setting depth, Tubing size, FHTP and a Pump/Motor has been selected Check sensitivity to  Changing

Reservoir Pressure  Increasing watercut 

Check Sensitivity to  Increase

no of stages to increase flexibility if required  Operating frequency

ESP Analysis: Op. Frequency (VFD) 



Return to Analysis - Operating Point and select Sensitivities... Note that Sensitivity 2 is set to Operating frequency with values: 30, 45, 60, 75 and 90 Hz

ESP VFD Sensitivity

ESP VFD Sensitivity minimum rate best efficiency rate

maximum rate

ESP Analysis : WaterCut Sensitivity 



Return to Analysis - Operating point and select Sensitivities... Note that sensitivity one is set to water cut with values : 0, 25, 50, 75, 99 %

ESP Analysis : WaterCut sensitivity

99% Water cut

0 % Water cut

ESP & Simulation VFP Tables 

After all sensitivity runs have been done select ‘Analysis - Export VFP file...’ to input VFP tables to a simulator. Following are typical requirements: Rate FTHP w.c. GOR Frequency b/d psia frac MSc/bbl Hz 100 50 0.0 0.49 30 200 100 0.1 45 300 200 0.25 60 500 300 0.5 75 750 500 0.75 90 1000 750 0.99 6 x 6 x 6 x 1 x 5 = 1080 runs

ESP Design: Manual Intervention 

Manual Calculations required for :  Packer

Selection  Protector Design  Tubing Stresses  Junction Box, transformers, switchboard