Downhole Packer with Nested Piston Activation for Controlled Perforation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for perforating downhole well casings are often unreliable and lack control, particularly in tight formations where limited hydraulic working area restricts the force available for operating tools, and there is a need for a more controlled and efficient method to fracture formations for oil and gas production.
Innovation Solution
A perforating tool with a body and moveable cutter blocks, activated by a system of pistons in pressure chambers, which uses fluid pressure to deploy cutter blocks for controlled perforation and can be used in conjunction with a packer apparatus to provide an annular seal for hydraulic fracturing, allowing for increased force and compact operation in small diameters.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If explosives are used to perforate well casing, then perforation can be achieved, but the method is unreliable and lacks control
Solution Approach 1:
The patent replaces the explosive mechanical system with a controlled mechanical cutting system. Cutter blocks with cutting edges are driven outward by pistons to mechanically cut through the casing, providing reliable and controllable perforation without using explosives. The activation member moves the cutter blocks between retracted and deployed positions under control of the activation system.
Solution Approach 2:
The patent employs a hydraulic activation system where fluid pressure is applied to pistons to move the activation member, which in turn deploys the cutter blocks. The bore is filled with fluid under pressure, and this hydraulic force is transmitted through the activation member to reliably drive the cutters outward for controlled perforation.
2Adaptability or versatility
If downhole tool diameter is reduced for tight formations, then tool can access small diameter casings, but hydraulic working area and available force are reduced
Solution Approach 1:
The patent implements a nested configuration where multiple pistons are arranged concentrically within the activation member bore. The first piston is disposed within the bore, and a second piston is disposed within the first piston, creating a compact nested arrangement that maximizes the number of pistons and available force within a small diameter tool body.
Solution Approach 2:
The patent transitions from a single-dimensional linear arrangement to a multi-dimensional concentric arrangement of pistons. By stacking pistons in concentric circles within the bore, the system increases the total piston surface area and available hydraulic force without increasing the external diameter of the tool, enabling operation in small diameter casings.
3Force
If multiple pistons are added to increase force, then available hydraulic force increases, but tool complexity increases
Solution Approach 1:
The patent reduces complexity by nesting multiple pistons concentrically within the single bore of the activation member. This unified structure allows multiple pistons to be controlled by a single fluid pressure source and a single activation sequence, avoiding the complexity of multiple separate hydraulic systems while still providing increased force through the combined action of multiple pistons.
Data Source
AI summary
A packer apparatus usable in a downhole well casing or an open borehole to provide an annular seal in the well casing or borehole. The packer apparatus includes an activation member disposed in body wherein the activation member is moveable relative to the body to deform an elastomeric packer element outwardly relative to the body to form an annular seal in a well casing in use. A plurality of pistons is arranged to move the activation member relative to the body, each piston being disposed in a respective pressure chamber arranged to be filled with fluid in response to an increase in fluid pressure in the body.