Method for measuring relative slippage of spiral component of marine flexible pipeline based on DIC

Abstract

The invention discloses a method for measuring relative slippage of a marine flexible pipeline spiral component based on DIC, and relates to the field of marine flexible pipeline structure response analysis, and the method comprises the steps: determining the position of the cross section of a pipeline; peeling off the outer skin of the pipeline in the smooth curvature area of the pipeline, and exposing the outermost spiral component layer; respectively marking a pipeline cross section loop line and an outer curvature axial straight line; marking mark points on the outer surface of each spiral component; recording absolute displacement vectors of all mark points based on a DIC technology; serving the mark points located on the outer curvature axial straight line as reference points, and obtaining relative displacement vectors of other mark points relative to the reference points through calculation; and mapping all mark points except the reference point to the same phase of the outer surface of the spiral component where the reference point is located, so that the problem that the sliding response of the marine flexible pipeline spiral component relative to the internal component cannot be directly measured is solved, and the method has the advantages that a test piece is not damaged, and the method is not in contact with the surface of a pipe body.

Description

technical field [0001] The invention relates to the field of structural response analysis of marine flexible pipelines, in particular to a DIC-based measurement method for the relative slippage of helical components of marine flexible pipelines. Background technique [0002] Offshore flexible pipelines are an important type of transportation equipment in the development of deep-water oil and gas resources. They are usually composed of multi-layer metal helical members with winding layers and non-bonded composites. The most complicated form of stress is the tensile helix located on the outermost member. When the pipeline is subjected to axial tensile load and transverse bending at the same time, due to the large friction between the layers, the helical member presents a typical stick-slip shape, that is, as the curvature gradually increases, the single helical member The slip morphology changes of the internal cylindrical components will be significantly different, which wil...

AI Technical Summary

Problems solved by technology

But in reality, the inner component is wrapped by the outer helical member and the gap between the helical members of the same layer is very small, so it is impossible to mark the mark point on the surface of the inner component, so how to measure the spiral by only marking the mark point on the surface of the helical member The slip pattern of the component relative to the internal components is a key problem to be solved

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