Title : From lab to field: Designing high-temperature metallic seal solutions for sustained casing pressure remediation
Abstract:
Objective:
Sustained Casing Pressure (SCP) is a significant integrity challenge in oil and gas wells. A portion of these wells are in high-temperature environments. The industry continues to seek solutions that enhance long-term sealing performance under high pressure and high temperature downhole conditions. This study brings together materials science and field application to develop a high-temperature metallic sealing material engineered for casing pressure remediation
Methodology:
The development of the downhole metallic alloy involved two distinct phases. The first phase consisted of a lab-scale evaluation of the alloy’s performance under simulated downhole conditions. The sealing alloy was designed and fabricated in the laboratory, with its melting point determined and key properties—such as tensile strength, compressive strength, ductility, microstructure, crystal structure, and thermal expansion—characterized at room temperature. These mechanical properties were further evaluated at elevated temperatures, reaching up to 150°C.
The second phase involved testing a full-scale setup that closely mimics actual downhole conditions, including realistic casing weights and grades, maximum melting temperatures of 200°C, and pressures up to 5000 psi. The sealability of the alloy was assessed using differential hydraulic pressure tests across the solidified alloy, aiming to plug the SCP source. The results of these tests established the foundation for direct field application, ensuring the alloy plug performs reliably in high-temperature gas environments while maintaining both structural integrity and sealing efficiency.
Results:
By combining fundamental materials science with specific oil and gas applications, we established a robust workflow for material discovery and optimization. Transitioning from detailed material performance testing to upscaled testing under extreme downhole conditions enabled the progression from a 2-gram laboratory test to a 400-kilogram field-scale test. This comprehensive dataset guided the engineering of a next-generation sealing material optimized for high-temperature SCP remediation. Early results indicate acceptable thermal stability, controlled expansion properties, and strong mechanical performance, validating the material’s potential for field implementation.
