Crossover of integral-ring buckle arrestor: Computational results

Deepwater pipelines are susceptible to catastrophic collapse as a result of the propagating buckle phenomenon. To limit the damage inflicted on the pipeline, stiffeners known as arrestors are placed at certain intervals along the pipeline. A computational technique for the analysis of the ''integral-ring'' arrestor (also known as the heavy walled arrestor), which appears to be most efficient, is presented in this paper. In an attempt to understand the dynamics of arrestor crossover, both the quasi-static and dynamic crossover pressures are computed and compared for a pipe-arrestor combination that has been tested by Johns et al. (1978). In agreement with experimental findings, the computational results indicate only a small difference between quasi-static and dynamic crossover pressures for this pipe-arrestor combination. Furthermore, it is shown that the interaction between the pipe and the pressurizing fluid may account for an increase in the dynamic crossover pressure above the quasi-static value.