Seafloor Pipeline Burying with Float Support Devices
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for laying and burying pipelines at the seafloor, such as co-trenching and post-trenching, face challenges including pipeline deformation or collapse due to stress from uneven excavation, requiring multiple small-depth passages that lengthen the operation time and increase the risk of damage.
Innovation Solution
A group and method utilizing a trenching machine with float devices connected to the pipeline to support it during excavation, reducing stress and allowing deep excavations in fewer passages, using a series of float devices with hooking and sliding mechanisms to maintain pipeline stability and control the excavation process.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If co-trenching or post-trenching methods are used to bury pipelines at the seafloor, then the pipelines are protected from local factors such as fishing, navigation, and wave-motion, but the pipelines are subjected to stress that causes deformation or collapse
Solution Approach 1:
The patent applies preliminary action by positioning support devices on the seafloor before the trenching operation begins. These support devices are placed at predetermined locations along the pipeline route, creating a support structure in advance that will be engaged by the pipeline during trenching, thereby preventing stress-induced deformation before it occurs.
Solution Approach 2:
The patent introduces support devices as intermediary elements between the pipeline and the seafloor. These devices act as mediators that transfer and distribute the loads from the pipeline to the seafloor, preventing direct stress concentration on the pipeline during the trenching operation, thus maintaining pipeline structural integrity while still achieving burial protection.
2Strength
If successive small-depth passages are used during excavation to reduce pipeline span, then pipeline deformation is reduced, but the overall operating period is lengthened
Solution Approach 1:
The support devices are positioned in advance along the pipeline route before trenching begins. This preliminary placement allows for deeper, more efficient excavation passages since the support structure is already in place to prevent pipeline span issues, eliminating the need for multiple small-depth passages and reducing overall operating time.
Solution Approach 2:
The support devices are designed to be dynamically engaged during the trenching operation. As the trenching machine progresses, the pipeline naturally engages with the pre-positioned support devices, allowing for adaptive support that maintains pipeline integrity throughout the excavation process without requiring multiple incremental passes.
3Ease of manufacture
If pre-trenching is used on compact seafloors, then the pipeline can be laid in a prepared trench, but a much larger excavation than the pipeline dimension is required
Solution Approach 1:
The support devices are pre-positioned at specific locations along the pipeline route rather than excavating a continuous wide trench in advance. This selective preliminary placement allows for more efficient excavation that is closely matched to the actual pipeline dimensions and support requirements, reducing unnecessary excavation volume while still facilitating easy pipeline laying.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
Enables pipeline positioning in situ with reduced stress, allowing for deep excavations in fewer passages, thereby shortening the overall laying and burying time while minimizing pipeline damage.
Implementation Method 1
a plurality of float devices (14) connected to the digging device (11) and constrainable to the pipeline (15)
Data Source
Figure 1~2c
Figure 3
Figure 4
AI summary
A device includes a digging device to cut the seafloor and with a device for hooking onto a pipeline and for sliding over the same. The device includes at least one float device constrainable to the pipeline for supporting it in span, connected to the back of said digging device with respect to the direction of the movement. The method includes excavating the seafloor by a digging device, collecting a float device from a storage base and transporting it to said pipeline, constraining the first float device to the pipeline behind the digging device and connecting the first float device to the digging device, when at least one portion of pipeline is in a suspended configuration, and when the portion of suspended pipeline increases, collecting a subsequent float device and constraining it to the pipeline and connecting the same to the float device previously constrained.