Tri-Axial Shock Absorber Sub for Drillstring Vibration Coverage
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing drillstring vibration dampening tools are not effective in reducing vibrations in all dimensions and are not readily tunable to address the specific vibration modes of a particular drilling operation, leading to accelerated fatigue and sub-optimum drill rates.
Innovation Solution
A tri-axial shock absorbing sub with a tubular main stem and integrated axial, torsional, and lateral shock absorbing assemblies, utilizing spring systems and hydraulic dampening mechanisms to absorb vibrations in multiple dimensions, and can be tailored to specific vibration frequencies through adjustable spring constants and fluid dynamics.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If multiple separate dampening tools are used to address different vibration dimensions, then vibration dampening coverage is improved, but device complexity increases
Solution Approach 1:
The patent combines axial, lateral, and torsional dampening assemblies into a single integrated shock absorbing sub that can be inserted into one drillstring component. The main stem houses multiple spring systems and dampening mechanisms that operate simultaneously across all three vibration dimensions, eliminating the need for multiple separate tools and reducing overall device complexity while maintaining comprehensive vibration coverage
Solution Approach 2:
The shock absorbing sub is designed as a universal component that performs multiple dampening functions simultaneously. The single device addresses axial vibrations through axial springs, lateral vibrations through lateral springs with wedge inserts, and torsional vibrations through torsional springs with helical cam surfaces, making it a multi-functional solution that replaces multiple specialized tools
2Ease of manufacture
If fixed dampening characteristics are used, then manufacturing simplicity is improved, but adaptability to different vibration modes deteriorates
Solution Approach 1:
The dampening characteristics are made adjustable through dynamic configuration options. Spring constants can be modified by changing wire diameter, coil density, or active coil count. The number and arrangement of springs in each assembly can be adjusted to match specific vibration frequencies and amplitudes, allowing the same basic device structure to be tuned for different drilling conditions and vibration modes
Solution Approach 2:
The patent enables parameter adjustment of the dampening system by varying spring physical properties such as wire diameter, mean coil diameter, and number of active coils. These parameter changes allow customization of the spring constant to match specific vibration frequencies encountered in different drilling operations, providing adaptability without requiring complete redesign of the device
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
Effectively dampens vibrations across multiple axes, reducing drillstring fatigue and improving drilling efficiency by absorbing vibrations at resonance and high excitation levels, allowing for tailored frequency responses to match drilling conditions.
Implementation Method 1
A spring system is positioned to resist movement of the reaction collars away from the activator ring, whereby lateral movement of the main stem causes the wedge inserts to move the reaction collars against the spring system
Implementation Method 2
A spring system configured to resist axial movement of the load collar relative to the sub housing
Implementation Method 3
A spring system positioned to resist movement of the first and second helix sleeves away from one another; whereby rotational movement of the main stem causes the first and second helical cam surfaces to move (i) the first and second helix sleeves apart, and (ii) at least one of the first or second helix sleeves into engagement with the spring system
Data Source
AI summary
A downhole shock absorbing sub which includes a tubular main stem extending through a sub housing and a lateral shock absorbing assembly positioned within the sub housing. The lateral shock absorbing assembly includes an activator ring positioned around the main stem, the activator ring including a plurality of wedge inserts positioned around a perimeter of the activator ring. A reaction collar is positioned on each side of the activator ring with the reaction collars including ramp surfaces engaged by the wedge inserts. A spring system is positioned to resist movement of the reaction collars away from the activator ring, whereby lateral movement of the main stem causes the wedge inserts to move the reaction collars against the spring system.