Flexible Pipe End Fitting for Hydrostatic Seal Pressure Equalization
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The design and manufacturing of flexible pipes for the oil and gas industry are complex and costly due to the need to withstand high internal and external pressures, and existing testing methods are cumbersome and prone to user error.
Innovation Solution
The development of an end fitting for flexible pipes that includes a fluid communication passageway pressure-resistant to high pressures, allowing for the differential pressure approach in design and enabling the communication of local hydrostatic pressure to internal regions of the end fitting.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If conventional design methods are used to withstand high external hydrostatic pressure, then the flexible pipe structure must be large and heavy, but this increases material costs and logistical complexity
Solution Approach 1:
The invention changes the pressure parameter distribution within the end fitting by introducing a fluid communication passageway that equalizes pressure between the external port and the seal chamber. This parameter change allows the seal elements to experience differential pressure rather than full external hydrostatic pressure, enabling a lighter structural design while maintaining strength requirements.
Solution Approach 2:
The fluid communication passageway acts as an intermediary mechanism that transfers external hydrostatic pressure from the external port to the seal chamber. This intermediary allows indirect pressure equalization, enabling the seal elements to function under reduced pressure differential while the external structure can be optimized for weight.
2Reliability
If conventional testing methods are used to test seal integrity, then complex hydro test procedures are required, but these are time-consuming and prone to user error
Solution Approach 1:
The invention enables self-testing capability by allowing external hydrostatic pressure to automatically communicate through the fluid communication passageway to the seal chamber. The system uses the surrounding seawater pressure itself to test seal integrity, eliminating the need for complex external hydro test equipment and procedures.
Solution Approach 2:
The invention uses hydraulic principles by utilizing fluid (seawater) communication through the passageway to transmit pressure for testing purposes. The hydraulic connection between the external port and seal chamber allows pressure-based testing without mechanical test equipment.
3Reliability
If overestimation of environmental conditions is used in design, then the flexible pipe can meet reliability requirements, but this requires complex and costly manufacturing processes
Solution Approach 1:
The invention changes the pressure distribution parameters within the end fitting to achieve more efficient stress utilization. By equalizing pressure through the fluid communication passageway, the design can use actual environmental conditions rather than overestimated values, reducing manufacturing complexity while maintaining reliability.
Solution Approach 2:
The invention introduces a dynamic pressure equalization mechanism that adapts to actual external hydrostatic conditions. The fluid communication passageway allows the internal seal chamber pressure to dynamically match external pressure, enabling the structure to be optimized for actual rather than worst-case conditions.
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
This solution allows for a smaller, lighter flexible pipe structure for given internal design pressures, reduces material and logistical costs, and provides a more efficient method for testing seal integrity without the need for complex hydro tests.
Implementation Method 1
a fluid communication passageway, pressure resistant to at least about around 9652.67 kPa (1400 psi), extending between the external port and the inner port for communicating pressure between said external port and said inner port
Data Source
Figure 1
Figure 2
Figure 3A
AI summary
A flexible pipe, a method of testing a seal and an end fitting are disclosed. The flexible pipe comprises a segment of flexible pipe body comprising a first pipe body end and a further pipe body end and at least one end fitting comprising at least one external port and a corresponding fluid communication passageway extending between the port and a location between a pair of spaced apart seal elements sealed against at least one internal fluid retaining layer of the flexible pipe body. The fluid communication pathway is pressure resistant to at least about around 1400 psi for communicating pressure between the external port and the location between the pair of spaced apart seal elements.