Foldable Mudmat Layout for Subsea In-Line Pipeline Accessories
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current marine pipelaying techniques face challenges in integrating large in-line accessory structures into pipelines, particularly due to space constraints on pipelaying vessels and the need for stable mudmat foundations on soft seabeds, which limits the size and stability of accessories that can be deployed.
Innovation Solution
The design of an in-line accessory structure with inclined branches and foldable mudmats that can be compactly stored and expanded on the seabed, allowing for reduced size and lower center of gravity during deployment, enabling stable support of heavy accessories and accommodating larger mudmat areas for enhanced load-bearing capacity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If large in-line accessory structures are integrated into pipelines onboard a pipelaying vessel, then the pipeline can be fabricated with operational flexibility and field layout capabilities, but the space constraints on the vessel limit the size and complexity of accessories that can be accommodated
Solution Approach 1:
The in-line accessory structure is divided into separate modular components: the accessory itself (valve, connector, or other subsea structure), the support frame, and the mudmat foundation. These segments can be assembled in different configurations and sizes depending on vessel space availability, while still achieving the desired pipeline operational flexibility when deployed.
Solution Approach 2:
The mudmats are designed to expand from a compact stowed configuration during vessel transport to a fully deployed configuration on the seabed. This dimensional transformation allows the structure to fit within limited vessel space while providing adequate foundation area on the seabed to support large accessories and maintain pipeline operational flexibility.
2Reliability
If heavy accessories are supported by mudmat foundations on soft seabeds, then the accessories and attached pipe remain stable without excessive settlement, but the mudmats require sufficient area to prevent overturning and excessive lateral movement
Solution Approach 1:
The mudmats are designed with movable connections to the support frame, allowing them to transition from a compact state during transport to an expanded state when deployed on the seabed. This dynamic configuration enables the mudmats to provide sufficient foundation area for stability while minimizing the space required during vessel operations.
Solution Approach 2:
The support frame and mudmats are pre-assembled in a compact configuration that can be handled and transported by the vessel's equipment. Once positioned on the seabed, the mudmats are deployed to their full area to provide the necessary foundation stability, eliminating the need for complex on-seabed assembly operations.
3Ease of operation
If the in-line accessory structure is designed with a compact configuration for vessel transport, then it can be integrated into the pipeline firing line, but the structure must be expanded on the seabed to provide adequate support area
Solution Approach 1:
The structure incorporates movable mudmats that can transition between compact and deployed configurations. During vessel operations, the mudmats are held in a compact stowed position that allows the entire assembly to pass through the firing line. Once on the seabed, the mudmats are deployed to provide adequate foundation area, simplifying the operation while managing structural complexity.
Solution Approach 2:
The structure is segmented into the accessory, support frame, and mudmat components with standardized connections. This segmentation allows for easier assembly and configuration management, reducing operational complexity while maintaining the ability to transition from compact transport to deployed support configurations.
Data Source
Figure 1
Figure 2~3
Figure 4
AI summary
An in-line accessory structure for a subsea pipeline comprises: at least one mudmat that is movable relative to the frame from a compact stowed state into an extended deployed state; a frame attached to the mudmat; an elongate pipe section supported by the frame, the pipe section being arranged to be integrated into the subsea pipeline; and a branch in fluid communication with the pipe section. At least one mudmat and at least one branch are disposed in longitudinal succession along the pipe section on each side of the pipe section, the mudmats on opposite sides of the pipe section being offset longitudinally from each other to define longitudinally-extending recesses with opposite longitudinal offset that accommodate the branches on opposite sides of the pipe section.