Session: 04-01-03 Flexible Pipes III

Submission Number: 180145

Analysis of the Influence of Sensitive Parameters on Deep-Sea Non-Metallic Unbonded Flexible Multiphase Pipe 

This paper addresses the technical issues of non-metallic unbonded flexible multiphase pipes in the field of deep-sea mining. From a theoretical perspective, it systematically explores the overall scheme design, the coupling mechanism of multi-physical fields, and the evolution law of structural strength. Aiming at the wind, wave, and current environmental conditions in 6000-meter deep-sea mining areas, research on the hydraulic lifting system of flexible multiphase flow pipes for deep-sea mining was conducted. Based on the flexible pipe transportation principle and the Bernoulli equation for two-phase flow, basic parameters such as pump station type, layout scheme, buoyancy block arrangement, and relay cabin were determined, and the overall scheme design of the deep-sea mining flexible multiphase flow system was carried out. A multi-body coupling dynamic model of the mining vessel - flexible multiphase flow pipe - pump station system - relay cabin was established. The dynamic characteristics of the ultra-long flexible multiphase flow pipe coupling system under complex environmental effects were analyzed, and cyclic optimization was carried out. The dynamic response characteristics of the ultra-long flexible structure under complex marine environmental loads were analyzed, and the influences of sensitive factors such as top tension load characteristics, bending radius, and mining vehicle displacement were studied. The effects of various parameters on the pipe strength performance were quantified, providing theoretical support and a scientific basis for the optimal design of deep-sea flexible multiphase  pipes.

Presenting Author: Liwei Li CNOOC Research Institute Ltd.

Presenting Author Biography: She has long been engaged in the design of deepwater subsea pipelines and deepwater risers. She has conducted research on the overall scheme for the flexible riser scheme in deep-sea mining, and carried out analysis on multiple sensitive parameters such as top tension and bending radius.

Authors:

Liwei Li CNOOC Research Institute Ltd.
Lusheng Jia CNOOC Research Institute Ltd.
Zijun Song CNOOC Research Institute Ltd.