Packer Extension Premium Thread Metal-to-Metal Seal
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing packer extension designs with two-step threaded connections experience axial play, leading to loss of metal-to-metal seal contact under tension, resulting in reliance on chevron seal stacks alone, which fails to meet regulatory requirements for dual seals.
Innovation Solution
The design replaces the anchor sub with an external premium thread on the production string that directly engages the packer extension, eliminating the need for a seal stack and ensuring a metal-to-metal seal in both tension and compression, and includes a left-hand square thread for retrieval.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If a two-step threaded connection is used to connect the production string to the packer extension, then the connection can be made, but axial play occurs causing the metal seal to lose contact under tension
Solution Approach 1:
The invention extracts and eliminates the intermediate anchor sub and seal stack components, directly connecting the production string to the packer extension through a single premium threaded connection. This removes the source of axial play while maintaining the sealing function through the premium thread's metal-to-metal seal capability.
Solution Approach 2:
The invention merges the connection function and sealing function into a single premium threaded connection. The VAM or tapered thread provides both the mechanical connection and the metal-to-metal seal simultaneously, eliminating the need for separate anchor sub and seal stack components.
2Strength
If the metal seal loses contact due to axial play and tension, then the connection remains intact, but only the chevron seal stack remains as the sole seal, failing regulatory requirements
Solution Approach 1:
The premium threaded connection acts as an intermediary that eliminates axial play between the production string and packer extension. By providing a rigid, play-free connection, it ensures that both the metal-to-metal seal and chevron seal stack remain engaged and functional simultaneously, satisfying dual seal requirements.
3Reliability
If a seal stack and seal bore are used with the anchor sub, then sealing is provided, but device complexity increases and cost increases
Solution Approach 1:
The invention extracts and removes the seal stack and seal bore components from the system. The premium threaded connection's inherent metal-to-metal sealing capability replaces the need for these additional sealing components, simplifying the overall device structure.
Solution Approach 2:
The premium threaded connection serves multiple functions simultaneously: it provides the mechanical connection between production string and packer extension, creates a metal-to-metal seal, and eliminates the need for separate seal stack and seal bore components. This multi-functionality reduces device complexity while maintaining sealing reliability.
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 provides a reliable metal-to-metal seal in all conditions, meets dual seal regulatory requirements, and offers cost savings and improved performance by eliminating the need for a seal bore and seal stack, while allowing for optional seal bore usage and efficient packer retrieval.
Implementation Method 1
a metal to metal seal results and the seal stack is eliminated
Implementation Method 2
Another adjacent left hand square thread is provided in the packer extension for removal of the packer after the packer is released
Data Source
AI summary
A production sting has a premium thread preferably VAM or similar for threading into a packer extension without the need for a seal stack to engage a seal bore in the extension. The seal bore use becomes optional and a metal to metal seal is provided by the premium thread whether the string is in compression or tension. Another adjacent left hand square thread is provided in the packer extension to land accessory tools or for removal of the packer after the packer is released in a variety of known ways. Either the premium thread or the left hand thread can be in the uphole position on the packer extension.