Cavity Shot Tool Liquid Propellant Initiation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current explosives used in cavity shot systems for plug and abandonment (P&A) operations are restricted, dangerous to handle, and can be unintentionally initiated, making them unsuitable for cost-effective and safe P&A operations.
Innovation Solution
A downhole cavity shot tool featuring a housing with a reactive propellant material and an initiator assembly with a high explosive initiator, which ignites the propellant to create an explosive shockwave, collapsing casings and formations to form a cavity without the need for hazardous materials or handling.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If traditional explosives (nitroglycerine dynamite) are used in cavity shot systems, then the cavity shot can create effective barriers for P&A operations, but the explosives are restricted for transport, dangerous to handle, and can be unintentionally initiated
Solution Approach 1:
The patent changes the chemical state of the propellant from solid (dynamite) to liquid form, which fundamentally alters the safety parameters. Liquid propellants are not subject to the same transportation restrictions as solid explosives, can be handled more safely, and cannot be unintentionally initiated by extraneous energy sources. This parameter change resolves the contradiction by maintaining the explosive functionality while eliminating the safety and availability problems associated with traditional solid explosives.
2Productivity
If traditional explosives are used for cavity shot, then the barrier creation is effective, but the cost and complexity of handling and transporting hazardous materials increases
Solution Approach 1:
The patent extracts the hazardous aspects from the cavity shot system by removing traditional explosives and replacing them with liquid propellant. This extraction eliminates the need for special handling procedures, safety protocols, and restricted transportation arrangements, thereby reducing operational complexity and cost while maintaining the cavity shot's effectiveness in creating barriers for P&A operations.
3Reliability
If safer alternatives to traditional explosives are used, then handling safety improves, but the effectiveness of creating the explosive shockwave may be compromised
Solution Approach 1:
The patent employs a composite approach by combining liquid propellant with a booster charge in a staged initiation system. The liquid propellant provides safe handling characteristics, while the booster charge ensures reliable and powerful initiation. This composite material strategy resolves the contradiction by maintaining the safety advantages of liquid propellants while ensuring the shockwave generation capability required for effective cavity shot operations.
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 tool provides a safer, more accessible, and cost-effective means for creating a natural barrier in wellbores during P&A operations, reducing the risk of accidental initiation and environmental hazards.
Implementation Method 1
initiation of the high explosive initiator ignites the reactive propellant material, creating an explosive shockwave
Implementation Method 2
ignites the reactive propellant material, creating an explosive shockwave, collapsing casings and formations
Data Source
AI summary
A method and apparatus for providing a cavity shot tool into a wellbore in a plug and abandonment application, containing liquid propellant within propellant bags, initiated by an RF-Safe modular initiator, igniting the liquid propellant above a casing plug to collapse the casing, wellbore and/or formation onto itself, to create a natural barrier that is then sealed with cement.