Quick evaluation method for tensile performance of multi-layer non-sticking flexible pipe

Abstract

The invention provides a quick evaluation method for tensile performance of a multi-layer non-sticking flexible pipe. According to the quick evaluation method, the structural parameters of the multi-layer non-sticking flexible pipe are measured through a dedicated measuring tool; the mechanical parameters of materials used by all functional layers of the multi-layer non-sticking flexible pipe are determined through a material tensile test; a three-dimensional geometry model of the multi-layer non-sticking flexible pipe is subjected to grid partition by aid of finite-element pre-processing software; and frictional contact in each layer and between the layers are considered, a flexible pipe three-dimensional finite-element model is established, calculation is conducted through non-linear finite-element analyzing software ABAQUS, and the stress characteristics, under the axial tensile load effect, of the multi-layer non-sticking flexible pipe are obtained. On the basis of the von Mises stress peak values of all the functional layers and the corresponding material yield strength of all the functional layers, the safety coefficients, under the condition of the current load working condition, of all the functional layers are calculated and determined, the minimum values of the safety coefficients of all the functional layers serve as the basis, and the propose of tensile performance evaluation of the multi-layer non-sticking flexible pipe is achieved. The quick evaluation method has very important significations on recognizing the stress distribution characteristics of the multi-layer non-sticking flexible pipe under the axial tensile force effect, clarifying tensile performance of the multi-layer non-sticking flexible pipe and ensuring safe operation.

Description

technical field [0001] The invention relates to the technical field of oilfield drilling, in particular to a method for quickly evaluating the tensile performance of a multilayer non-bonding flexible pipe. Background technique [0002] Unbonded flexible pipelines are essential equipment in the exploitation of offshore oil and gas resources. With the continuous advancement of human beings into the deep sea, the marine environment they face is becoming more and more harsh, and the axial tension on flexible pipes is also increasing. Big. In order to ensure that flexible pipe can meet the harsh service environment, its tensile properties should be evaluated before use. [0003] Full-scale physical experiment is a reliable method to evaluate the comprehensive mechanical properties of flexible pipes. However, it is expensive, takes a long time, and cannot intuitively reflect the internal force characteristics of flexible pipes under complex loads. Using numerical simulation to e...

AI Technical Summary

Problems solved by technology

However, the structural analysis of unbonded flexible pipes is very complicated. The models used by most researchers either greatly simplify the model, or do not consider the characteristics of frictional contact between layers, so there is a certain gap between the obtained results and the real force characteristics of flexible pipes.

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