Downhole Rod Pump Control for Gas Interference and Fluid Fillage
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Downhole pump inefficiencies due to incomplete fluid fillage, gas interference, and excessive stress on pumping components lead to component failures, increased operating costs, and reduced production efficiency in oil and gas wells.
Innovation Solution
An autonomous control method for the down-hole pump surface unit that adjusts pump operation characteristics such as dwell time, polished rod travel, compression ratio, and pump cycle rate based on weight transfer position, rate of weight transfer, and stretch factor to minimize gas interference and optimize production.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If the downhole pump operates with incomplete fluid fillage or gas interference, then the pump can continue running, but excessive stress and strain are inflicted on pumping components leading to failures
Solution Approach 1:
The system performs preliminary detection of fluid fillage and gas interference conditions before they cause component damage. By monitoring weight transfer position and rate of weight transfer in advance, the control system can adjust pump operation parameters proactively to prevent excessive stress on components, thereby maintaining both operational continuity and component reliability
Solution Approach 2:
The system continuously monitors downhole conditions through weight transfer measurements and uses this feedback to dynamically adjust pump operation characteristics. The feedback loop enables real-time optimization of dwell time, polished rod travel, compression ratio, and pump cycle rate to prevent harmful conditions while maintaining productive operation
2Adaptability or versatility
If the traveling valve travels excess distance before contacting resistive fluid level, then the pump can handle variable fluid levels, but energy is wasted and fluid pound occurs causing shock loading
Solution Approach 1:
The system dynamically adjusts the polished rod travel distance and pump cycle parameters based on real-time detection of fluid level position and weight transfer characteristics. This dynamic adaptation allows the pump to accommodate variable fluid levels while optimizing the travel distance to minimize energy waste and prevent fluid pound shock loading
Solution Approach 2:
The control system changes operational parameters including dwell time, compression ratio, and pump cycle rate based on detected downhole conditions. By adjusting these parameters in response to fluid level variations, the system maintains adaptability while improving energy efficiency and preventing excessive shock loading
3Productivity
If the pump compression ratio is increased to force traveling valve open, then fluid transfer improves, but excessive stress is applied to downhole components
Solution Approach 1:
The system performs preliminary detection of traveling valve status and fluid fillage conditions before initiating high-compression cycles. By identifying conditions that require forced valve opening in advance, the system can apply compression ratio increases only when necessary, improving fluid transfer while minimizing unnecessary stress on components
Solution Approach 2:
The system uses feedback from weight transfer position and rate measurements to continuously optimize compression ratio settings. This feedback control ensures that high compression ratios are applied only when needed to force the traveling valve open, thereby improving fluid transfer efficiency while minimizing excessive stress on downhole components
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
Reduces gas interference, increases production efficiency, and decreases maintenance and operation costs by autonomously adapting to downhole conditions, ensuring optimal fluid transfer and component longevity.
Implementation Method 1
The polished rod string assembly has an inherent stretching and compressing natural tendency as it operates the downhole pump in motion being lifted and lowered by the surface unit
Implementation Method 2
As the polished rod string is lowered it must compress and pressurize the pump intake fillage volume from previous intake stroke now trapped within the working barrel and above the standing valve
Implementation Method 3
The energy creating the 'pound' is generated from the falling kinetic energy made up of the polished rod string plus fluid column load multiplied by its velocity multiplied by its distance traveled in a given time frame, all of which is suddenly forced to stop and release or transfer some of this falling energy
Data Source
AI summary
A method for the autonomous control of a surface unit of an oil well or gas well down-hole rod pump to provide for a reduction of gas interference and an increase in production, the method providing for autonomous adjustment of one or more pump operation characteristics, including one or more of dwell time, polished rod travel, compression ratio, and pump cycle rate, and the method including autonomous determination of a weight transfer position, autonomous determination of a rate of weight transfer, determination of a stretch factor of the polished rod, and autonomous adjustment of one or more of the pump operation characteristics for successive pump cycles of the down-hole pump installation based upon the weight transfer position, the rate of weight transfer, and the stretch factor.