Improving artificiallift system performance

Phoenix Artificial LiftDownhole Monitoring

Optimized performance Phoenix* artificial lift downhole monitor-ing systems enable optimized productionand lift system performance in wells withan electrical submersible pump (ESP), aprogressing cavity pump (PCP), a beam(rod) pump, or a gas lift completion. Real-time monitoring tools and accurate datareduce the need for operator intervention,improve well integrity, and maximize pro-duction and ultimate recovery. Phoenix

systems can protect assets and help ensureboth the reservoir and completion deliverto their full potential.

Proactively identifying problems resultsin substantial cost reduction when thereare prompt and effective remedial actions.Good data eliminate the guesswork that canresult in ineffective and costly interventionstrategies. With accurate downhole informa-tion, operators can make better decisionsto optimize well production.

Applications■ Lift system and completion

performance monitoring

■ Wells with potential startupor instability problems

■ Wells with changing productivity and sandfaceconditions over time

■ Reservoir drainage and depletion monitoring

Benefits■ Reduced deferred production

through longer lift systemrun life

■ Lower operating costs throughbetter lift system management

■ Reduced early well-life failures

Features■ Optimization of pump and

production performance

■ Optimized well interventionplanning

■ Family of instrumentationadaptable to any lift system or application

■ Accurate, continuous monitoring of multiple keyparameters

■ Compatible with supervisorycontrol and data acquisition(SCADA) systems usingModbus protocol

■ System operation independentof pump power

■ Continuous data stream viaRS232 and RS485 ports onsurface equipment

■ Programmable trip andalarm relays for all parameters monitored

■ Analog outputs and inputs

■ Onsite historical data storageusing data logger

■ Selectable rapid samplingrate for reservoir monitoring

Monitoring System Parameters

Parameters MultiSensor* MultiSensor Select Select Select Select SelectMeasured XT Type 0 XT Type 1 CTS LITE Standard Advanced† Reservoir

Current leakage • • • • • • •Discharge pressure • • • • •Discharge temperature • • • •Discharge vibration • • • •Intake pressure • • • • • • •Intake temperature • • • • • • •Intake vibration •Motor temperature • • • • • •Motor vibration • • • • • •Motor Y volts • • • •Sandface pressure •Sandface temperature •Sandface vibration •Temperature rating (°F [°C]) 257 [125] 257 [125] 302 [150] 302 [150] 302 [150] 302 [150] 302 [150]Pressure accuracy (psi [kPa]) ±10 [69] ±10 [69] ±5 [34] ±5 [34] ±5 [34] ±5 [34] ±3 [21]

† Phoenix Select Advanced gauge measures pump intake pressure at the pump, allowing detection of blocked intakes.

SCADA

TRIP

1 2 0 0 P i P S I2 2 0 0 P d P S I1 2 1 . 9 T i C

A L A R M M O R E Remote real-time data surveillance and controlCurrent leakage

Intake pressure

Intake temperature

Intake vibration

Sandface pressure

Sandface temperature

Sandface vibration

Onsite data logging

Motor temperature

Motor vibration

Y-point voltage

Discharge pressure

Discharge temperature

Discharge vibration

Available measurements from the Phoenix Select* monitoring system configured for an ESP completion.

Systems to suit your artificial lift needsWhatever your artificial lift method,Schlumberger provides a Phoenixdownhole monitoring system for yourapplication: the Select digital gauge—configurable for all lift systems—andthe MultiSensor XT analogue ESPmonitoring tool.

Monitoring System Applications

Monitoring System ESP PCP/Beam pump/Gas lift/Jet pump

MultiSensor XT •Select • •

Improving ESP and well performance

ESP artificial lift systems are effectivefield-proven completion systems particu-larly suitable for wells with low bottom-hole pressure, low bubblepoint, high watercut, and high volumes. ESP systems oftenreplace gas lift when there is insufficientgas to sustain the flow. Either the PhoenixSelect or MultiSensor XT monitoringsystems can monitor ESP and well performance. Careful monitoring willextend pump run life and contribute toimproved production. Together this helpsreduce your total lift system costs.

Achieving optimum performance from PCP systems

PCP systems produce high efficiencies,are a low-capital investment, and reducemaintenance and operating expenses.When effective data are used, PCP wellsachieve significant improvements. Anextensive database and experienceenable Schlumberger to recommendthe right Phoenix gauge for the job.

Optimizing production in gas lift wells

Catastrophic failures in many artificial liftsystems are abrupt. Production immediatelydeclines—or drops to zero—and the causesare often obvious. A failing gas lift system,however, may not be noticed for weeksor even months. While some of the effectsof the failure appear as lower productionrates, these rates could also be easilyattributed to conditions other than a failingor inefficient gas lift system. Consequently,a loss of production can rapidly add upto tens of thousands of barrels.

Monitoring and protection for beam pump systems

Pressure data taken below the beampump helps monitor drawdown and canprevent the unit from pumping off.Vibration monitoring gives warning ofpump wear or pounding. In addition,buildup surveys using real-time pressure

measurement below the pump are con-ducted without pulling rods and runningslickline memory gauges.

Measurement flexibility

The Phoenix Select and MultiSensor XTmonitoring systems offer a broad rangeof downhole measurements for multipleartificial lift system types and manufac-turers. With flexibility in the configurationof your downhole monitoring system,you can be confident in selecting theright system for your application.

A technician verifies Phoenix gauge quality during manufacturing.

Phoenix Warning Measurements in ESP Applications

Measurements Application

Current leakage Alarm protects electrical system from deterioration from high pump heat, breakdown of winding insulation, and phase-to-ground insulation loss.

Discharge pressure High-pressure alarm and trip protect the pump from closed-valve shut-ins and heavy fluid slugs.

Discharge temperature High-temperature alarm and trip protect the pump from overheating.Intake pressure Low-pressure alarm and trip protect the pump from low-fluid level, pump-off

due to blocked intakes, and gas locking.Intake temperature High-temperature alarm and trip protect pump from high-temperature intake

recirculation and elevated production fluid temperature.Motor oil or winding temperature High-temperature alarm and trip protect motor from low-flow conditions, high

motor load, and poor cooling because of scale.Motor and pump vibration Vibration alarm protects pump from mechanical damage from high-solids

production and excessive mechanical wear resonance frequency.Y-point voltage Motor Y-point voltage alarm detects imbalance in the electrical system downhole.Sandface pressure Pressure measured remotely from the ESP facilitates accurate transient analysis

of build surveys for well performance monitoring.Sandface temperature Well temperature is measured away from the ESP, unaffected by its heating.Sandface vibration Vibration measures remotely from the ESP providing early indication of solids

production.Pressure differential Low- or high-pressure alarm and trip protect the pump from upthrust in high-flow

conditions and downthrust in low-flow conditions.

Phoenix Warning Measurements in PCP Applications

Measurements Application

Discharge pressure High-pressure trip protects the pump from closed-valve pressure buildups and accidental shut-ins.

Pressure differential High-pressure alarm and trip protect the pump from running out of head range.Intake pressure Low-pressure alarm and trip protect the pump from low-fluid level, pump off,

and damage from high gas volumes.Temperature protection High-temperature trip protects pump from high-temperature conditions.Pump vibration Vibration alarm protects pump from mechanical damage from high-solids

production and excessive stator wear and resonance frequency.

Phoenix Warning Measurements in Beam Pump Applications

Measurements Application

Intake pressure Low-pressure alarm and trip protect the pump from low-fluid level, pump-off, and damage from high gas volumes.

Pump vibration Vibration alarm protects pump from mechanical damage from high-solids production and excessive mechanical wear and pounding.

Phoenix Warning Measurements in Gas Lift Applications

Measurements Application

Annulus pressure Sensor system automatically detects and warns of injection pressure change and pressure instability downhole.

Tubing pressure System warns of increasing weight in the tubing column from poor injection orincreasing water cut.

Reliability built inSchlumberger has a history ofhigh-quality, reliable downholemeasurements and has beenproducing downhole gauges forover 60 years.

The accelerated life testingapproach is now standard forSchlumberger downhole tools.This process is adapted fromthe aerospace and automobileindustries and applied to theunique demands of the oil field.Emphasis is placed on testingearly in the development cycle bythe application of stress cyclesin excess of the operationallimit. Schlumberger productsare submitted to temperaturecycles, shock cycles, andvibration testing.

Field applications Phoenix monitoring systems protect yourartificial lift system. Each measured param-eter can be programmed with a shutdownthreshold and linked directly to the lift drivesystem, protecting your assets againstdamaging conditions. The units, in combina-tion with a SCADA or remote surveillancesystem, warn instantly when a well’s operat-ing performance changes. The operator, or acontrol system, can then take quick andeffective remedial action to restore optimumoil production or system performance. Inaddition, a normally operating artificial liftsystem can be continuously optimized toreact to changes in operating conditions.

The Phoenix system also providesvaluable information about productivityand reservoir performance, includingopportunities for pressure transient analy-sis, inflow performance monitoring, and productivity trending. The Phoenix data isa powerful complement to the operator’sreservoir performance-monitoring program.

Compatibility and integrationWith a high level of control and protection,Phoenix systems are SCADA-ready. TheModbus remote terminal protocol portprovides remote monitoring and control.Both the RS232 and RS485 port optionsare onboard for a continuous data streamas required. In fields with multiple artificiallift systems, Phoenix technology meansone data acquisition and communicationsplatform for all wells.

The UniConn* universal site controllerprovides operators with a single commonplatform for protection, control, and dataacquisition (both local and remote) forall ESP applications—fixed speed orvariable speed.

Phoenix systems are also designed forcompatibility with real-time remote systems.Schlumberger offers the espWatcher*surveillance and control system for ESPs.

Pressure testing the Phoenix MultiSensor XT downhole gauge.

Select system for PCP. Select system forgas lift.

Select system for beam pumps.

Reliability and experiencePhoenix sensors have been helping oper-ators manage their artificial lift operationssince 1992. The MultiSensor system wasthe world’s first multiparameter ESP gaugeand has now been installed in more than2,000 wells worldwide. Additionally,Schlumberger has been the industryleader in downhole permanent monitoringsystems since they were first introducedin the early 1980s. Significant experienceand success have continually improvedthe quality and reliability of our downholesensors. The same commitment anddedication have enabled Schlumbergerto deliver the latest generation of sensorsin the Phoenix Select system.

The value of dataDownhole measurement data fromPhoenix Select and MultiSensor systemsare used for in-depth analysis, diagnostics,and remediation planning in wells andfields on artificial lift. The productionincreases for one operator, shown below,are the result of analysis and recommen-dations from the LiftPro* optimizationservice utilizing Phoenix gauge data.

ESP performance monitoring using the espWatcher service.

0200400600800

1,0001,2001,4001,6001,800

1 2 3 4 5 6 7 8 9 10

Net

oil,

BLP

D

0

500

1,000

1,500

2,000

2,500

3,000

Cum

ulat

ive

net o

il, B

LPD

Production prior to analysisProduction after recommendation

Cumulative gains

Wells

Results of effective use of data. Significant production gains using Phoenix monitoring and LiftPro optimization.

MultiSensor XT system for ESP.

A systems approachextending to thereservoir Schlumberger has developed amodular systems approach toimproving artificial lift wellperformance. Our approachdeploys high-quality, reliable liftproducts, such as REDA* ESPand Camco* gas lift systems,instrumented with Phoenixmonitoring equipment. Next,the espWatcher surveillance andcontrol system and the LiftProoptimization service make fulluse of instrumented downholelift systems to optimize systemand well performance.

This systems approach canbe extended to include fieldoptimization studies that evaluateand provide the following:

■ well performance modeling

● data validation

● fluid and reservoir inflowconditions and performancecharacterization

● completion design, diag-nostics, and matching thecompletion to existing wells

● individual well performancecurve development

■ field system modeling

● flowlines, pipelines, andmanifolds modeling

● well performance curves

■ integration of episodic meas-urements and interventions

● production tests and pressure transient tests

● PVT* pressure-volume-temperature software andsampling data incorporation

● integration of other surfacemeasurements or ad hocproduction logging

● integration of well stimula-tion or treatment services.

espWatcher serviceThe Schlumberger espWatcher surveil-lance and control service for ESP systems features remote data acquisition; datatransmission, alarms, and alerts via satellite;remote pump startup and speed control;and remote resolution of certain pumpproblems. The espWatcher service isenabled by InterACT* real-time monitoringand data delivery. Remote connectivity andviewing of REDA ESP systems, variablespeed drive (VSD) controllers, and Phoenixartificial lift monitoring systems contributeto improved production and lift systemperformance.

The espWatcher service can help improvethe operation of submersible pumps andwell production in a number of ways:

■ surveying pump performance againstpump curve models

■ surveying well performance against well models

■ comparing VSD operating plans toupdated models of the pump and completion

■ detecting early changes in reservoir and sandface properties

■ maintaining formation integrity and controlling water coning

■ making pressure transient tests.

Supported by Schlumberger Data &Consulting Services, the service is an end-to-end data acquisition and managementservice to ensure minimized risk and ahigh level of performance.

The flexibility of the espWatcher servicemakes it suitable for mature fields with alarge number of producing wells, remoteenvironments where physical access isrestricted or difficult, or in fields whereSCADA is limited or unavailable.

Analysis and interpretation The key to any meaningful performanceanalysis is synchronized and validateddata. Phoenix systems form an integralpart of the LiftPro service to identify andremediate underperforming artificial liftwells. This rigorous four-step optimizationprocess relies heavily on the right data todeliver more oil and a longer well life.

LiftPro serviceApproximately two out of three artificiallylifted wells have the potential for signifi-cantly improved operation and increasedproduction. The LiftPro service baselineperformance goal is to tune a well’s opera-tion for a 10% increase in net oil production.The LiftPro service

■ identifies an underperforming artificially lifted well

■ uses the appropriate technology toidentify why the well is underperforming

■ provides recommendations and implementation

■ validates results.

The Schlumberger LiftPro service consistsof these four steps:

Acquire

■ Candidate selection is an importantpart of the optimization process. Onlywells with a high potential for gain are targeted.

Analyze

■ Artificial lift and well testing expertiseis combined with advanced well diag-nosis tools, such as LiftPro XP artificiallift system analysis software.

Execute

■ The sensitivity of well performance for various parameters can be preciselypredicted.

Evaluate

■ A complete dataset, available ondemand at the wellsite or deliveredremotely, enables operating personnelto test settings efficiently and accurately.The result is prompt before-and-afterwell production results with a very shortturnaround to improved well operation.

The LiftPro service uses a proven array of permanent and temporary data acquisitionsystems, such as Phoenix monitoring sys-tems, Sensa* fiber optics, and PhaseTester*multiphase periodic well testing equipment.

Production optimization through espWatcher and LiftPro services.

POCKET

04-AL-075 ©Schlumberger

March 2005 *Mark of Schlumberger

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