Experimental and Numerical Study of Lateral Indentation for Pipe-in-Pipe Structures

Pipe-in-pipe (PIP) flowlines have been widely arranged in offshore oil and gas fields for transportation, to achieve a significant thermal insulation capacity outstanding resistance external loads. However, the lateral indentation mechanisms of these multilayer pipelines are more complicated than those single-layer pipelines. In this paper, change deformation laws PIP structure were studied by experimental numerical methods, three stages behavior during observed. The effects diameter wall thickness inner outer pipes on relationship between load also studied, which provided reference design analysis structures.