Telescopic Stage Cementer Packer Sleeve Mechanism
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing single-stage cementing process for subterranean wells often fails to effectively cement the entire wellbore, making it impractical in some cases, and thus a multi-stage cementing process is employed using staging tools within the casing string to facilitate cement flow and annulus diversion.
Innovation Solution
A stage cementing tool with a mandrel, compression set packer, and movable sleeves that transition through distinct positions to align cement flow ports with the annulus, allowing cement to flow from the casing to the wellbore annulus, ensuring complete cement placement.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If a single-stage cementing process is used, then the process is simple and quick, but it is impossible or impractical to cement the entire wellbore effectively
Solution Approach 1:
The wellbore is divided into multiple cementing stages or zones, with each stage addressed by a separate cementing operation using staging tools. This allows the cementing process to be broken down into manageable sections that can be completed effectively, ensuring complete cementation of the entire wellbore while maintaining operational efficiency
2Reliability
If multi-stage cementing with staging tools is employed, then complete cementation of the wellbore is achieved, but the device complexity and operational difficulty increase
Solution Approach 1:
The staging tools are designed with nested or telescopic structures where components are housed within one another. The sleeves contain cement flow ports that can be exposed or covered by movable components, and the entire staging tool assembly is integrated within the casing string. This nesting reduces the overall device complexity while maintaining the multi-stage cementing capability
Solution Approach 2:
The staging tool is designed to perform multiple functions: it serves as both a cement diversion device and a flow control mechanism. The same structural components (sleeves, ports, packers) are used to both divert cement into the annulus and control the timing and location of cement flow, reducing the need for separate specialized components
3Manufacturing precision
If staging tools with movable sleeves and ports are used, then precise cement flow control is achieved, but the operational steps and time required increase
Solution Approach 1:
The staging tool is pre-configured with sleeves containing cement flow ports in specific locations along the casing string. The tool is installed in the wellbore with the ports initially covered, and the exposure of ports is triggered automatically by predetermined conditions such as pressure differentials or mechanical activation during the cementing process. This preliminary configuration reduces operational time by eliminating the need for manual positioning or activation of each port during the cementing operation
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
Enables efficient cement distribution and placement across the wellbore, overcoming the limitations of single-stage cementing by ensuring thorough cementation in sections, thereby enhancing wellbore stability and integrity.
Implementation Method 1
a compression set packer movable from an unset to a set position
Data Source
AI summary
A stage cementing tool has a mandrel defining a central flow passage and a plurality of cementing passages in a wall thereof. A packer is disposed about the mandrel. A closing sleeve is detachably connected to and movable relative to the mandrel. An opening sleeve defining a plurality of fully open cement flow ports therethrough is telescopically movable relative to the closing sleeve and movable relative to the mandrel. The opening sleeve is movable to move the packer to the set position, and thereafter movable to open a cement flow path between the central flow passage and an annulus defined by the stage cementing tool and the wellbore.