Cam-Driven Downhole Vibration Assembly Against Bit Whirl
Solution Overview
Problem
Existing downhole drilling technologies face challenges with excessive friction and torque, leading to increased drilling tool temperature and wear, as well as damaging effects like lateral vibration, bit whirl, and stick slip, which negatively impact drilling efficiency and tool longevity.
Innovation Solution
A vibration assembly is integrated into the drilling tool, comprising an axial assembly with a pulser and shock tool, and a radial assembly with expanders, which generate axial and radial movements to offset these damaging effects by vibrating and pulsing against the wellbore wall, thereby centralizing the tool and increasing rate of penetration.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional drilling is performed without vibration assembly, then drilling tool can maintain stable position, but excessive friction and torque occur leading to increased temperature and wear
Solution Approach 1:
The patent applies mechanical vibration through a vibration assembly that generates axial and radial vibrations during drilling operations. These vibrations reduce friction and torque between the drilling tool and wellbore wall, thereby decreasing heat generation and extending tool life without compromising drilling stability
2Productivity
If drilling tool operates continuously without vibration, then drilling progress can be maintained, but damaging effects like lateral vibration, bit whirl, and stick slip occur
Solution Approach 1:
The vibration assembly operates periodically, generating controlled axial and radial vibrations at specific frequencies. This periodic action counteracts harmful drilling effects such as lateral vibration, bit whirl, and stick slip by introducing beneficial vibrational cycles that reduce friction and improve drilling efficiency
3Reliability
If vibration assembly is added to drilling tool, then friction and torque are reduced extending tool life, but device complexity increases
Solution Approach 1:
The vibration assembly is integrated into the existing drilling tool structure by combining axial and radial vibration mechanisms within a unified housing. This merging approach extends tool life through reduced friction and torque while minimizing the increase in device complexity through consolidated design
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 vibration assembly effectively reduces damaging drilling effects, increases drilling efficiency, and extends tool life by minimizing friction and torque, allowing for more effective wellbore penetration and stabilization of the drilling tool.
Implementation Method 1
The vibration spring may be a Bellville spring. The vibration assembly may also include a mandrel spring thereabout to urge the mandrel to a retracted position
Implementation Method 2
The mandrel may have a cam surface thereon to engage the expanders as the mandrel moves about the housing whereby the expanders are radially extendable and retractable thereabout
Implementation Method 3
a radial vibrator operatively connectable to the expanders to vibrationally move the expanders against the wall of the wellbore whereby movement of the downhole tool is altered during drilling
Data Source
AI summary
A vibration assembly of a drilling tool for drilling a wellbore penetrating a subterranean formation is disclosed. The downhole drilling tool includes a drill string, a bottomhole assembly and a drill bit. The vibration assembly includes a housing (334a) operatively connectable to the bottomhole assembly, expanders (122) positionable in the housing and radially extendable and retractable thereabout, and a radial vibrator (comprising mandrel (446), enlarger spring (48), cam portion (458) and vibration spring (570) operatively connectable to the expanders to vibrationally move the expanders against the wall of the wellbore whereby movement of the downhole tool is altered during drilling.