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Beam Pumping Workshop Houston, Texas October 4 - 7, 2005. Total Well Management. Lynn Rowlan. Analysis STEPS to Apply the Concept of Modern Total Well Management:. Analyze the well’s inflow performance to determine if additional production is available.
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Beam Pumping Workshop Houston, Texas October 4 - 7, 2005 Total Well Management Lynn Rowlan
Analysis STEPS to Apply the Concept of Modern Total Well Management: • Analyze the well’s inflow performance to determine if additional production is available. • Determine the overall efficiency to identify wells that are candidates for improvement. • Analyze the performance of the pump. • Analyze the performance of the down hole gas separator. • Analyze mechanical loading of rods and pumping unit. • Analyze performance of prime mover. • Design modifications to existing system. • Implement changes and verify improvement.
ACOUSTIC SURVEYS ANSWER THE FOLLOWING WELL PERFORMANCE QUESTIONS: • What is the depth to the top of the liquid? • Does liquid exist above the pump? • Does the liquid in the casing annulus restrict production? • What is the maximum production rate available from the well? • What is the casing-head pressure? Does it restrict production? • What is the percentage of liquid in the annular fluid column? • Is gas flowing up the annulus? At what rate? • What is the gas gravity? • Are there any restrictions or anomalies in the annulus?
SINGLE and MULTI- SHOT ACOUSTIC TESTS • SINGLE SHOT ACOUSTIC TESTS DETERMINE THE LIQUID LEVEL DEPTH , BOTOM HOLE PRESSURES AND WELL INFLOW PERFORMANCE AND THE MAXIMUM PRODUCTION RATE. • MULTI-SHOT PRESSURE TRANSIENT TESTS DETERMINE THE PERFORMANCE OF THE FORMATION, SKIN DAMAGE AND RESERVOIR PRESSURE. • MULTI-SHOT ACOUSTIC LIQUID TRACKING TESTS PERMIT LIQUID LEVEL TRACKING IN WORKOVER AND DRILLING OPERATIONS.
Acoustic Time to Well Depth Relationship 1. TheDepthfrom the gun to an anomaly in the casing annulus is directlyproportionalto thetime, RTTT,for the acoustic pulse to travel from the gun down the casing to the anomaly and reflect back to the microphone. 2. Microphone housed in the gas gun detects the blast from the shot and reflected sound from collars, liners, perforations, liquid level, plus other obstructions in the annulus.
LIQUID LEVEL ANALYSIS Depth to Down-Hole Anomaly
LIQUID LEVEL ANALYSISAutomatically Count Collars to Liquid Level Other Methods: Acoustic Velocity Downhole Marker
LIQUID LEVEL ANALYSIS Measure Annular Gas Flow Rates • Test casing-pressure-buildup by closing the casing valve while the well pumps and gas flows for a short time into the annulus. • The rate at which casing pressure increases is measured. • Accurate annular gas flow rate & %liquid can be determined from a casing pressure buildup test. Measurement of small pressure changes require precision instrumentation.
DYNAMOMETER SURVEYS ANSWER THE FOLLOWING QUESTIONS: • Is the well pumped off? • What is the pump intake pressure? • What is the pump fillage? And pump displacement? • What is the current pumping speed? • Are the traveling and/or standing valves leaking? • Are the maximum and minimum rod loads within limits? • What is the polished rod and pump horsepower? • Is the gearbox overloaded? Is the unit properly balanced? • What movement of the counterweights will balance the unit? • Is the downhole gas separator operating effectively?
Dynamometer Analysis: • Surface Dynamometer cards for designing and diagnosing surface problems. • Rod String • Pumping Unit • Pump Problems • Excessive Friction • Pump card for analysis of downhole problems. • Unanchored Tubing • Tubing Leak • Pump Problems • Excessive Friction Surface Card Pump Card
Are Traveling And Standing Valve Load Tests OK? Traveling Valve Test Traveling Valve Load Testshows load loss during valve check due to the diametric clearances (0.008” above) between the pump plunger and barrel.
Well Starts up With Low Pump Fillage After Being Down 10 Minutes Indicating A Poor Downhole Gas Separator System Efficiency is 39% mainly due to a poor gas separator
After Installation of a Good Gas Separator, Well Starts Pumping with Complete Pump Fillage After Being Down 10 Minutes • After gas Separator Pumped Off 37 Full Strokes System Efficiency increased from 39 % to 54%
Measurement of Instantaneous Power TWO CURRENT SENSORS THREE VOLTAGE SENSORS
MOTOR POWER SURVEYS ANSWER THE FOLLOWING QUESTIONS: • What is the overall electrical efficiency of the pumping system? • Is the overall electrical efficiency above 50%? • What is the power consumption, $/month, $/BBL, and power demand, KW? • What is the motor current? Does the motor overheat? • Does the motor generate electricity at some time during the stroke? Is credit allowed for generation? • Is the gearbox overloaded? • Is the pumping unit properly balanced? • What movement of counterweights required to balance unit?
OVERALL SYSTEM EFFICIENCY • OVERALL SYSTEM EFFICIENCYIS DEFINED AS THE AMOUNT OF THEORETICAL WORK REQUIRED TO LIFT THE LIQUID FROM THE NET LIQUID LEVEL DEPTH TO THE SURFACE DIVIDED BY THE AMOUNT OF POWER SUPPLIED TO THE MOTOR • RESERVOIR PERFORMANCE ANALYSIS • MOTOR INPUT POWER MEASUREMENT
Motor Power and Electrical Cost Analysis Cost $ Power System Efficiency
PRESSURE TRANSIENT SURVEYS ANSWER THE FOLLOWING WELL PERFORMANCE QUESTIONS: • What is the reservoir pressure? • What is the producing bottomhole pressure? • What is the liquid/gas annular flow after the well is shut in? • Is there any wellbore damage? How much Skin? What's the Permeability? • Does the formation need treatment? • Is the well fractured?
Buildup Test: Bottom Hole Pressure vs. Time Original SBHP estimate
Goal is to answer the WELL PERFORMANCE QUESTIONS Time Requirement is about 45 minutes per well. Analyze collected data at the well. Make recommendations to fix any problems discovered. Record work necessary to fix problem as notes in the comments text box. When recommended changes completed, new data should be collected once the well stabilized Notice if well performance changed as planned. Follow-up on recommendations to learn from successes and failures Role changes from a data collector to a knowledgeable well analyst and problem solver. Artificial Lift Analyst Function:
AN OPERATOR TO ANALYZE THE PERFORMANCE OF WELLS IMPROVE OPERATIONS LESS TIME AND EFFORT EXPENDED INCREASE OIL AND GAS PRODUCTION REDUCE THE OPERATING EXPENSE. MODERN TOTAL WELL MANAGEMENT OF ARTIFICIAL LIFT WELLS PERMITS: