Floating Apparatus Bonding Material Micro-Annulus Seal
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current floating equipment used in cementing operations experiences leakage due to micro-annulus formation between the cement and the outer sleeve or valve, leading to contamination and failure in maintaining hydraulic pressure, which is exacerbated by increased performance testing requirements.
Innovation Solution
A floating apparatus with a bonding material applied to the inner and outer surfaces of the outer sleeve and valve housing, respectively, to create a resilient bond with the cementitious material, preventing micro-annulus formation and enhancing both hydraulic and mechanical retention.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If cementitious material is used to bond the valve to the outer sleeve, then the bond strength is improved, but micro-annulus formation occurs due to cement shrinkage during curing
Solution Approach 1:
The patent uses a composite bonding system combining cementitious material with a bonding material (such as epoxy or other adhesive materials) to bond the valve to the outer sleeve. This composite approach allows the cement to provide compressive strength while the bonding material compensates for shrinkage effects and prevents micro-annulus formation, thereby maintaining both bond strength and sealing integrity.
Solution Approach 2:
The patent modifies the bonding process by introducing a separate bonding material layer between the cementitious material and the valve/outer sleeve interfaces. This additional layer changes the bonding parameters, allowing for compensation of dimensional changes during cement curing while maintaining strong adhesion and preventing leakage paths.
2Force
If conventional float equipment is used to reduce casing weight, then the equipment lowering stress is reduced, but leakage occurs through micro-annulus allowing cement to re-enter casing
Solution Approach 1:
The bonding material (such as epoxy) creates a composite sealing system that works in conjunction with the cementitious material to provide both mechanical support and hydraulic sealing. This composite approach ensures that the float equipment maintains its weight-bearing function while preventing cement leakage through the annulus, thereby improving reliability.
Solution Approach 2:
The bonding material acts as an intermediary layer between the cementitious material and the valve housing/outer sleeve interfaces. This intermediary prevents direct contact between cement and the annular space, blocking the leakage path while allowing the cement to continue providing compressive bond strength.
3Strength
If high compressive strength cement is used to affix the valve, then the bonding strength is improved, but shrinkage during curing causes micro-annulus and leakage
Solution Approach 1:
The patent combines high compressive strength cement with a flexible bonding material that can accommodate shrinkage. The cement provides the necessary compressive strength for bonding, while the bonding material (such as epoxy) fills and seals the gaps created by shrinkage, preventing micro-annulus formation and subsequent leakage.
Solution Approach 2:
The patent converts the harmful effect of cement shrinkage into a beneficial outcome by using the bonding material to actively seal the gaps created during curing. Rather than trying to prevent shrinkage, the design accepts it and uses the bonding material to compensate, thereby eliminating leakage paths while maintaining bond strength.
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 solution provides a reliable, leakproof seal that withstands differential pressures and cyclic loading conditions, improving the integrity of the cementing process by preventing fluid contamination and ensuring the cement remains in place without requiring costly removal.
Implementation Method 1
A floating apparatus with a bonding material applied to the inner and outer surfaces of the outer sleeve and valve housing, respectively, to create a resilient bond with the cementitious material
Implementation Method 2
Over a period of time, the cement poured between the valve and the outer sleeve shrinks slightly as it cures
Data Source
AI summary
A floating apparatus for use in a casing string is provided. The apparatus includes an outer sleeve having a valve centrally positioned therein. A cement body is affixed to the check valve and the housing by use of a bonding material.