ESP Gas Lock Detection and Flushing Control
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Solution Overview
Problem
Conventional electrical submersible pump assemblies (ESPs) face inefficiencies and premature failure due to gas locks, which are difficult to resolve without shutting down the system, leading to lost production and potential damage.
Innovation Solution
A device and method that automatically detect gas locks by monitoring motor torque or current, maintaining operating speed to allow gas separation, reducing speed for flushing trapped gas, and returning to normal operation without shutdown, using a data monitoring and control system to optimize pump performance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the pump is stopped when gas lock is detected, then motor damage is prevented, but production time is lost due to shutdown and wait time
Solution Approach 1:
The system performs preliminary actions by maintaining pump speed temporarily after gas lock detection to allow gas separation, and then executes a controlled speed reduction to flush gas before returning to normal operation. This preliminary sequence of actions prevents the need for complete shutdown while still protecting the motor from damage.
Solution Approach 2:
The system dynamically adjusts pump operating speed based on gas lock detection and resolution stages. Instead of a static stop-start approach, the pump speed is modulated through different phases (maintenance phase, flushing phase, recovery phase), allowing continuous operation with optimized speed profiles that prevent motor damage while minimizing production loss.
2Measurement precision
If a low current threshold is set to detect gas lock, then gas lock can be identified, but false shutdowns or missed detections occur with unsatisfactory thresholds
Solution Approach 1:
The system uses feedback mechanisms by continuously monitoring motor current and comparing it against dynamically adjusted thresholds. The detection algorithm incorporates historical data and system responses to refine threshold settings, reducing false positives and negatives while maintaining reliable gas lock detection and operational stability.
3Reliability
If the pump waits for fluid column dissipation before restart, then gas lock is resolved, but production efficiency decreases due to wait time
Solution Approach 1:
The system maintains continuous useful action by keeping the pump running at maintained speed during the gas separation phase, rather than stopping completely. The pump continues to move fluid and maintain pressure while gas bubbles rise and separate, eliminating idle wait time and maintaining production efficiency throughout the gas lock resolution process.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
Enables reliable detection and resolution of gas locks without operator intervention, maintaining production efficiency and preventing system shutdown, thereby extending pump lifespan and reducing downtime.
Implementation Method 1
allows the well fluid to remain above the pump in a static condition and allows the gas bubbles in the fluid to rise above the fluid, facilitating a separation of gas and liquid above the pump
Data Source
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AI summary
A device, method, and program product detect and break an occurrence of gas lock in an electrical submersible pump assembly in a well bore based upon surface or downhole data without the need for operator intervention. The system provides the ability to flush the pump and return the system back to production without requiring system shutdown. In addition, the system provides an algorithm for controlling a pump operating speed of the electrical submersible pump assembly to maximize production from the well bore.