Fluid-Energized Metal Hanger Seal for Damage-Free Retrieval
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing tubing and casing hanger seals require mechanical force to engage and are difficult to disengage, leading to potential damage to the housing and hanger during removal.
Innovation Solution
A hanger sealing system with a flow passage connected to an annular space, at least one seal chamber that expands when pressurized, and a metal surface encapsulating the seal chamber, allowing for pressurization to engage the seal and subsequent depressurization for removal without damage.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If mechanical force is used to energize the seal, then the seal can be engaged and seal the annular space, but the seal becomes difficult to disengage and may damage the housing and hanger upon removal
Solution Approach 1:
The patent replaces the traditional mechanical force-based sealing system with a fluid pressure-based system. Fluid is introduced into the seal chamber to expand the seal element, creating the sealing force needed to seal the annular space. This substitution allows the seal to be engaged through fluid pressure rather than mechanical force, making disengagement easier by simply releasing the fluid pressure.
Solution Approach 2:
The patent uses fluid pressure (pneumatics or hydraulics) to energize the seal. A seal chamber is provided that receives fluid under pressure, causing the seal element to expand and engage with the housing and hanger. The fluid pressure can be easily controlled and released, allowing the seal to be engaged when needed and disengaged for retrieval without damage.
2Reliability
If mechanical force is used to energize the seal, then the seal can be engaged, but excessive mechanical force may damage the housing and hanger
Solution Approach 1:
The patent replaces direct mechanical force application with fluid pressure application. The fluid pressure expands the seal element uniformly, distributing the sealing force across the seal surface rather than concentrating it at specific mechanical contact points. This reduces the risk of damaging the housing and hanger during seal engagement.
Solution Approach 2:
The patent changes the parameter of force application from mechanical (direct contact force) to fluid pressure (distributed force through fluid medium). This parameter change allows for more controlled and uniform application of sealing force, reducing peak stresses that could damage the housing and hanger while maintaining effective sealing.
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 seals the annular space with minimal mechanical force, allowing for easy disengagement and reduced risk of damage to the hanger and housing during removal.
Implementation Method 1
The at least one seal chamber can expand when pressurized
Data Source
AI summary
An annular hanger seal for sealing a tubing or casing hanger comprising a flow passage, at least one seal chamber, and a metal surface. Pressure can enter the hanger seal through the flow passage causing the at least one seal chamber to expand. Expansion of the at least one seal chamber can cause sealing contact between the metal surface around the at least one seal chamber and the housing, the hanger, or both surfaces. The seal can later be punctured or otherwise depressurized to break sealing contact for removal of the hanger from the annular space.