Passive Pressure Sealing With Compensator Devices
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing sealing systems between rotating and stationary elements in drilling operations face challenges in preventing fluid leakage, withstanding high pressures and speeds, and maintaining ease of use and repair, especially in configurations involving drill pipes and washpipes.
Innovation Solution
A sealing system with at least three sealing elements arranged in series, utilizing a barrier fluid arrangement with compensator devices that have a pressure difference created by varying cross-sectional areas of pistons, and a filling mechanism to provide barrier fluid at a given pressure, ensuring passive sealing and minimizing external fluid lines.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional sealing systems are used in drill pipe connections, then the system can maintain simplicity and ease of repair, but the system cannot effectively prevent fluid leakage under high pressure and high speed drilling conditions
Solution Approach 1:
The sealing system is divided into multiple sealing elements (at least three) arranged in series between the process fluid and environment. Each sealing element handles a portion of the sealing function, allowing the system to effectively prevent fluid leakage under high pressure while maintaining a modular structure that is manageable and repairable.
Solution Approach 2:
A barrier fluid is introduced as an intermediary substance between the sealing elements. This barrier fluid creates a protective layer that enhances the sealing capability, preventing process fluid from leaking through the sealing elements while the compensator devices manage the barrier fluid pressure to maintain optimal sealing conditions.
2Stress or pressure
If hydrodynamic seal lubrications with multiple pressure retaining seals are used to withstand high pressure, then the pressure resistance is significantly improved, but the device complexity and number of components increases
Solution Approach 1:
The compensator devices automatically adjust the barrier fluid pressure in response to process fluid pressure changes. The system uses the process fluid pressure itself to drive the compensators, which then maintain appropriate barrier fluid pressure to keep sealing elements properly lubricated and sealed, eliminating the need for external control systems or complex pressure management mechanisms.
Solution Approach 2:
The cross-sectional area of the piston in the compensator device is specifically designed with a difference between the two sides. This geometric parameter change creates a pressure differential that allows the compensator to generate the necessary barrier fluid pressure to maintain sealing effectiveness under high process fluid pressure conditions.
3Reliability
If multiple compensator devices with different pressure requirements are used to divide process fluid pressure, then the pressure distribution is optimized for sealing, but the assembly and filling process becomes more complex
Solution Approach 1:
The sealing system is designed to be filled with barrier fluid through filling means before active use. This preliminary filling action ensures that all compensator devices receive the barrier fluid at the appropriate pressure in advance, establishing the correct pressure distribution across the sealing elements before the system begins operation, thereby simplifying the overall assembly process.
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
The system effectively prevents fluid leakage, withstands high pressures and speeds, and simplifies maintenance by dividing process fluid pressure between compensator devices, reducing wear and enhancing operational efficiency.
Implementation Method 1
the pressure in the process fluid is acting on one side of a piston in the compensator device and the pressure in the barrier fluid is acting on the opposite side of the piston
Implementation Method 2
There is a difference in the cross sectional area of the two sides of the piston and this difference varies between the at least two compensator devices. This gives that with a given compensator device there is a given pressure difference between the pressure in the process fluid and the pressure in the barrier fluid
Data Source
AI summary
A sealing system between a relatively rotating element and a stationary element has at least three sealing elements arranged between the rotating element and the stationary element and arranged in series between a process fluid and an environment, and a barrier fluid arrangement to provide a barrier fluid to spaces formed between the sealing elements. The barrier fluid arrangement has at least two compensator devices where under use the pressure in the process fluid is acting on one side of a piston in the compensator device and the pressure in the barrier fluid is acting on the opposite side of the piston. There is a difference between cross sectional areas of the two sides of the piston and the difference varies between the at least two compensator devices.