Wellbore plugs are critical subsurface barriers used to isolate permeable formations, prevent fluid and gas migration, and ensure long-term well integrity during temporary suspension and permanent abandonment. Plugging performance has increasingly been challenged by cyclic pressure–temperature loading, complex well architectures, and evolving regulatory expectations, particularly in underground natural gas storage and hydrocarbon storage wells, where repeated injection–withdrawal cycles impose sustained mechanical and hydraulic demands on barrier systems. At present, guidance on plugging...
Wellbore plugs are critical subsurface barriers used to isolate permeable formations, prevent fluid and gas migration, and ensure long-term well integrity during temporary suspension and permanent abandonment. Plugging performance has increasingly been challenged by cyclic pressure–temperature loading, complex well architectures, and evolving regulatory expectations, particularly in underground natural gas storage and hydrocarbon storage wells, where repeated injection–withdrawal cycles impose sustained mechanical and hydraulic demands on barrier systems. At present, guidance on plugging materials, design principles, verification methods, and regulatory requirements remains fragmented across standards, jurisdictions, and technical literature, making it difficult for practitioners to consistently design, evaluate, and justify reliable barrier systems.
This document provides an integrated review of wellbore plugging systems, synthesizing regulatory frameworks, industry practices, material technologies, and governing mechanical and hydraulic principles. It surveys temporary and permanent plugging applications, reviews cementitious and non-cementitious materials, examines key design parameters influencing sealability and durability, and summarizes integrity testing and verification techniques. Emerging materials and innovative plugging approaches are discussed alongside established cement systems, and persistent knowledge gaps are identified with respect to cyclic loading, interface mechanics, and long-term performance assessment. The review is structured to connect regulatory requirements with engineering design logic and material behavior, providing a coherent framework for understanding plug performance across operational contexts
The target audience includes petroleum engineers, well integrity specialists, regulators, and researchers involved in well design, operation, suspension, and abandonment. Practicing engineers can use this document to inform plug selection, design justification, and integrity verification strategies under site-specific conditions. Regulators and policymakers may use it as a reference to compare regulatory approaches and assess performance-based criteria. Researchers can leverage the identified gaps and mechanistic discussions to guide future experimental and modeling studies aimed at improving the reliability of wellbore barrier systems.