Whipstock Assembly for Milling-Free Wellbore Side-Tracking

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing wellbore side-tracking methods require cement plugs, ledges, and milling operations, which are time-consuming, complex, and pose safety risks, often resulting in poor window formation and excessive junk in the wellbore.

Innovation Solution

A whipstock assembly is used with a casing sub-assembly, incorporating packers and external anchors, to orient a drilling bottom hole assembly, eliminating the need for cement plugs and milling, and forming a window by fracturing the tubular body of the casing sub-assembly.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If conventional whipstock placement methods are used (requiring cement plugs and ledges), then the whipstock can be securely positioned, but the operation time increases and safety risks increase

Engineering Contradiction:

Improvewhipstock positioning reliabilityVSAvoidside-tracking operation time

Core Design Contradiction:

ReliabilityVSLoss of time

Solution Approach 1:

The invention extracts and eliminates the cement plug and ledge from the whipstock placement process. The whipstock assembly is directly placed in the wellbore without requiring these additional components, removing the time-consuming cementing and ledge-drilling operations while maintaining secure positioning through the whipstock's own engagement mechanism with the wellbore wall

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The whipstock assembly is designed with pre-integrated engagement features that allow it to be securely positioned upon direct insertion into the wellbore. The engagement surfaces and anchoring mechanisms are prepared in advance during manufacturing, eliminating the need for preliminary wellbore preparation steps such as drilling ledges or placing cement plugs

Inventive Principle:

Principle #10Preliminary action

2Ease of manufacture

If milling operations are used to create the window, then the window can be formed, but excessive junk is generated in the wellbore

Engineering Contradiction:

Improvewindow formation capabilityVSAvoidmilling junk in wellbore

Core Design Contradiction:

Ease of manufactureVSObject-generated harmful factors

Solution Approach 1:

The invention replaces the mechanical milling process with a fracturing mechanism. The window is formed by fracturing a tubular body using controlled mechanical forces applied to the casing sub-assembly, which breaks the tubular material into manageable pieces that can be easily removed or disposed of, rather than generating fine metallic junk through abrasion and grinding

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The invention changes the physical state and form of window formation from gradual material removal (milling) to sudden material fracture. By applying concentrated mechanical forces to exceed the fracture strength of the tubular body, the window is created instantaneously with minimal debris, changing the operational parameter from continuous cutting to discrete fracturing

Inventive Principle:

Principle #35Parameter changes

3Ease of operation

If multiple preparation steps (cementing, ledge drilling, milling) are performed, then the whipstock can be installed, but the operational complexity increases

Engineering Contradiction:

Improvewhipstock installation easeVSAvoiddrilling and completion operations complexity

Core Design Contradiction:

Ease of operationVSDevice complexity

Solution Approach 1:

The invention merges multiple separate operations (cement plug placement, ledge drilling, window milling, whipstock installation) into a single integrated operation. The whipstock assembly with its integrated engagement features and the fracturing mechanism for window formation are combined into one deployable unit that accomplishes all functions simultaneously upon insertion and actuation

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The whipstock assembly is designed as a multi-functional device that simultaneously performs positioning, anchoring, and window formation functions. The same assembly that positions the whipstock also contains the mechanism for fracturing the tubular body to create the window, eliminating the need for separate specialized tools and operations for each function

Inventive Principle:

Principle #6Universality (Multi-functionality)

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 approach reduces the time and complexity of wellbore drilling, improves safety, and ensures a high-quality window formation, avoiding issues like milling-induced junk and irregular shapes that can hinder later operations.

Implementation Method 1

forming a window by fracturing the tubular body of the casing sub-assembly

Methodology Applied

Scientific EffectFracture: Fracture Mechanics

Data Source

PatentUS12467318B2Side-tracking a wellbore

Publication Date: 2025.11.11 SAUDI ARABIAN OIL CO

AI summary

A whipstock assembly and a method for side-tracking a wellbore. The whipstock assembly includes a casing sub-assembly. The casing sub-assembly has a first rotating collar, a second rotating collar, and multiple bars. The bars are movable from a first position spaced apart from the first and second rotating collars to a second position extending between the first rotating collar and the second rotating collar. The bars are rotatable from the second position to a third position to open a window in the bars and form a ramp oriented toward the window.