Releasable Retrieving Tool Lug Slot Connection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for retrieving equipment from a blocked subterranean wellbore are inefficient due to the inability to conveniently separate and reconnect with lodged equipment, particularly in horizontal wellbores, leading to substantial delays and increased costs.
Innovation Solution
A dual-purpose apparatus comprising a housing tubular with lugs and a fishing tubular with corresponding slots, connected by shear pins, allowing for easy disconnection and reconnection to retrieve stuck equipment, designed to withstand the torques applied during drilling operations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If threaded safety joints are used to separate the drill string, then the uphole string can be salvaged, but many rotations are required and large forces are applied to the drill string causing damage
Solution Approach 1:
The separation tool is divided into distinct functional segments: a housing tubular, an inner tubular, shear pins, lugs, and slots. This segmentation allows the tool to perform multiple functions (separation and retrieval) through modular components that can independently execute specific tasks, eliminating the need for complex threaded joint operations
Solution Approach 2:
The invention changes the separation mechanism from threaded rotation to shear pin failure based on force parameters. The shear pins are designed to fail at specific force thresholds, enabling separation through controlled parameter change rather than multiple rotational cycles, thereby reducing operational complexity and protecting drill string integrity
2Productivity
If dedicated retrieval equipment is used after separation, then the lodged equipment can be recovered, but separate tools are required for each operation increasing time and cost
Solution Approach 1:
The separation tool is designed with dual functionality: it can both separate the drill string from lodged equipment and retrieve the equipment. The inner tubular can be disconnected to fish out the lodged equipment, and then reconnected to retrieve it, eliminating the need for separate dedicated retrieval tools and improving operational efficiency
Solution Approach 2:
The invention merges the separation function and retrieval function into a single integrated tool assembly. The housing tubular, inner tubular, lugs, and slots work together to provide both separation capability and equipment retrieval capability, reducing the total number of tools needed and streamlining the operational process
3Strength
If conventional fishing tools are used to reconnect with lodged equipment, then retrieval is possible, but the tools cannot withstand the torques applied during fishing operations
Solution Approach 1:
The lugs and slots are pre-configured in the housing tubular and inner tubular to provide reinforced connection points before fishing operations begin. This preliminary structural preparation ensures the tool can withstand the torques and forces encountered during fishing operations without failing
Solution Approach 2:
The tool assembly combines multiple components (housing tubular, inner tubular, lugs, slots, shear pins) made from materials selected for their ability to withstand specific stresses. The composite structure provides enhanced strength and durability during high-torque fishing operations compared to conventional single-purpose tools
Data Source
AI summary
Apparatus and methodologies for recovering equipment from a subterranean wellbore are provided, the apparatus operative to both disconnect uphole equipment from downhole equipment that has become lodged in the wellbore, salvaging the uphole equipment, and then to reconnect with the downhole equipment to fish the equipment from the wellbore. More specifically, the apparatus and methodologies comprise a modified fishing tool having two tubular portions that can be easily and efficiently be disconnected and reconnected with one another.