Tri-cam Linkage for Gripping Tool Stroke and Load
Solution Overview
Problem
Existing gripping tools for tubular running tools in oilfield applications have limitations in accommodating a wide range of work piece sizes due to restricted radial size and stroke capabilities, which restrict their utility in handling various tubular sizes effectively.
Innovation Solution
A tri-cam linkage system with bi-rotary to axial stroke activation and cam pairs that separate bi-rotary activation into two cam pairs, allowing for greater axial and radial stroke capabilities, enabling the tool to grip a wider range of tubular sizes by using a drive cam pair and a driven cam pair with distinct rotational inputs.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If a single cam pair is used for bi-rotary activation, then the device complexity is reduced, but the radial stroke and axial stroke capabilities are limited, restricting the range of tubular sizes that can be gripped
Solution Approach 1:
The single cam pair is segmented into two separate cam pairs: a drive cam pair and a driven cam pair. Each cam pair handles specific rotational inputs (right-hand and left-hand rotations respectively), allowing independent optimization of axial stroke and radial stroke capabilities. This segmentation enables the gripping tool to accommodate a wider range of tubular sizes while maintaining manageable device complexity through modular cam pair design.
2Adaptability or versatility
If the radial stroke is increased to accommodate larger tubular sizes, then the adaptability improves, but the mechanical stress and load capacity requirements increase
Solution Approach 1:
The cam pairs are designed with dynamic load distribution characteristics. The drive cam pair and driven cam pair work in sequence during bi-rotary activation, dynamically adjusting the mechanical stress distribution. This dynamic design allows the system to accommodate larger tubular sizes with increased radial stroke while managing load capacity requirements through progressive engagement of the cam pairs during the gripping cycle.
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 tri-cam linkage system enhances the operational range and load capacity of the gripping tool, allowing it to accommodate larger tubular sizes and providing improved grip force distribution, thus improving the efficiency and versatility of tubular running tools in oilfield operations.
Implementation Method 1
The cam linkage comprises: a drive cam body which receives rotational input tending to urge rotational movement, a driven cam body which receives rotational input solely from the drive cam body; a drive cam pair acting between the drive cam body and the driven cam body, such that rotational input is transmitted by the drive cam pair from the drive cam body to the driven cam body.
Data Source
Figure 1
Figure 2A~2B
Figure 3~4A
AI summary
An improvement in a gripping tool having a grip surface carried by movable grip elements and cam linkages to radially move the grip surface from a retracted to an extended position. The improvement involves a tri-cam linkage with cam pairs supporting bi-rotary to axial stroke activation and further cam linkages to cause radial stroke of the tool grip surface as a function of axial stroke.