Flexible Pipe Armour Layout for Lower Mass Under Deepwater Loads

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

The existing flexible pipes used in offshore oil exploitation face challenges with high mass due to metal tensile armor, which limits their capacity to handle both compressive forces at great depths and tensile forces, leading to increased weight and reduced efficiency.

Innovation Solution

A flexible pipe design incorporating both metal and composite tensile armor plies, where the composite tensile armor is positioned outside the metal armor with separation means to maintain radial and circumferential clearance, allowing for axial compression compensation and reduced mass.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If metal tensile armor plies are used to withstand compressive forces at great depths, then the pipe can resist external pressure, but the mass of the pipe increases significantly

Engineering Contradiction:

Improveresistance to compressive forcesVSAvoidmass of the flexible pipe

Core Design Contradiction:

StrengthVSWeight of moving object

Solution Approach 1:

The patent applies composite materials by combining metal tensile armor plies with composite tensile armor plies in a multi-layer configuration. The composite material layers (such as carbon fiber reinforced polymers) provide high specific strength and stiffness while having lower density than metal, thereby reducing the overall mass of the pipe while maintaining or improving its ability to withstand compressive and tensile forces at great depths.

Inventive Principle:

Principle #40Composite materials

Solution Approach 2:

The patent segments the tensile armor into distinct metal and composite layers, with metal plies positioned to handle compressive loads and composite plies positioned to handle tensile loads. This segmentation allows each material to be optimized for its specific function, with metal providing compression resistance and composite materials providing tension resistance with lower weight, thereby resolving the contradiction between strength and weight.

Inventive Principle:

Principle #1Segmentation

2Productivity

If the pipe structure is optimized to reduce mass, then the efficiency improves, but the capacity to handle both compressive and tensile forces may be compromised

Engineering Contradiction:

Improveefficiency of the flexible pipeVSAvoidcapacity to handle compressive and tensile forces

Core Design Contradiction:

ProductivityVSStrength

Solution Approach 1:

The patent applies local quality by assigning different material properties to different layers of the pipe structure. Metal tensile armor plies with high compression strength are positioned in specific layers to handle compressive forces, while composite tensile armor plies with high specific strength are positioned in other layers to handle tensile forces. This localized optimization of material properties allows the pipe to maintain high load-bearing capacity while minimizing overall mass, thereby improving efficiency without compromising strength.

Inventive Principle:

Principle #3Local quality

Data Source

PatentEP3601862B1Flexible pipe with layers of metal armour and layers of composite armour

Publication Date: 2022.05.11 IFP ENERGIES NOUVELLES

Figure 1~2
Figure 3

AI summary

Flexible pipe comprising a mechanical reinforcing element (4) and a pressure sheath, the mechanical reinforcing element (4) comprising at least one layer of metal traction armour sections (6) and at least one layer of composite traction armour sections (7) and the layer of composite traction armour sections (7) being arranged outside the layer of metal traction armour sections (6), separation means (8) being provided to separate the composite traction armour sections (7), while maintaining radial clearance and circumferential clearance for the composite traction armour sections (7).