Why conduct integrity assessments of wells?
Integrity assessments of wells evaluate the structural condition of the well and its ability to provide a competent, stable wellbore to access the target formations.
In addition, the design evaluates the serviceability of the wellbore in providing pressure containment and preventing the migration of liquids to overlying formations or to the surface.
This becomes especially important as industry and entrepreneurs propose to repurpose shut-in or abandoned wells for various new applications.
These new applications include:
- underground storage of hydrogen,
- carbon sequestration, geothermal energy production, and;
- lithium production.
Threats to Well Integrity
Well integrity can be compromised by several different threats including:
- Corrosion and cracking of the well casing
- Chemical or thermal degradation of the well cement
- Reservoir compaction and surface subsidence caused by reservoir pressure depletion
- Seismic activity
- Rod-tubing wear from reciprocating or rotating rod strings that are part of some artificial lift systems
- Operations in adjacent wells such as hydraulic fracturing or fluid injection as part of enhanced oil recovery (EOR) or underground storage operations
- Well intervention operations that cause extreme pressure cycles (surge/swab) or prolonged rotating or sliding in deviated intervals resulting in wear
Well integrity is typically assessed by running a suite of logging tools to identify defects such as wall loss, cracking of the casing and cement, parting of casing connections, leaks and casing deformations that can impair well access.
C-FER Yourself – Helping Improve Well Integrity
Testing
- Testing the performance of casing inspection logs in a full-scale simulated well with both natural and machined defects including cracks, external and internal corrosion, annular channels, deformations, and parted connections. These tests help well operators determine the resolution and accuracy of both conventional and thru-tubing logging tools and helps inspection service companies calibrate their tools to known well defects.
- Testing the performance of alternative cement formulations to determine suitability for thermal well operations or long-term underground storage operations
Calibrations
- Calibrating noise logs to identify the rate and composition (liquid or gas) of downhole leaks through casing.
- C-FER constructed a test well in the Deep Well Simulator with multiple, controllable leak ports where gas or water can be injected at different rates and locations to simulate a wide range of leak scenarios.
Software
- Developing WellXplore® software that uses multi-finger caliper or ultra-sonic casing inspection log data to construct three-dimensional images of deformed casing and tubing. The results identify pipe deformation mechanisms such as shear, buckling and collapse that can be used to guide and benchmark structural models of the interaction among the casing, cement and surrounding formation.
Quantitative Risk Analysis
- Calibrating noise logs to identify the rate and composition (liquid or gas) of downhole leaks through casing.
- C-FER constructed a test well in the Deep Well Simulator with multiple, controllable leak ports where gas or water can be injected at different rates and locations to simulate a wide range of leak scenarios.
Explore Our Laboratory
Laboratory
Overview
Explore our laboratory
equipment overview
Load Frames Overview
A variety of large-scale servo-hydraulic load frames to simulate complex loading scenarios representative of field conditions.
Deep Well Simulator
Develop and test a wide range of systems and products under precisely simulated downhole service conditions.
Contributor
Brian Wagg, MSc, PEng.
Director, Testing Services
With over 35 years with C-FER, Brian Wagg’s current focus is on applying C-FER’s analytical and full-scale testing capabilities to projects in clean energy including CCUS, hydrogen, geothermal and small modular nuclear reactors.
