Integrity Analysis of Casing Premium Connection under High Compression Load

Abstract

With the increasingly harsh conditions of complex oil and gas wells such as high-temperature and high-pressure deep wells and long-distance horizontal well, the integrity of casing string puts forward higher requirements for compression performance of premium thread connections. The requirements of high compression resistance of connection is complicated, including ensuring the integrity of structure and sealability for thread at the same time under high compression load being equal to the bearing capacity of casing body, and considering the structural fatigue, environmental fracture and seal failure caused by the weakening of thread bearing performance under cyclic load. Based on the failure cases of some casing connections, laboratory tests and finite element analysis results, this paper discusses the key technical points in the above mentioned problems, and provides the suggestions for the performance optimization of high-performance casing premium connections based on failure prevention.