Pre-installed Anti-rotation Key for Tubular Connectors
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current anti-rotation key designs for large diameter pipes in hydrocarbon drilling require complex tools and rig time for installation, often result in permanent deformation of connector members, and may not provide sufficient resistance against unscrewing, especially in larger diameter applications.
Innovation Solution
A pre-installed anti-rotation key system with a recess in one of the tubular members and grooves in the other, where the key ratchets along the grooves during make-up and is retained by a fastener, providing resistance primarily in the circumferential direction, eliminating the need for on-site installation tools and reducing axial load.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If traditional anti-rotation keys are installed on-site using specialty tools or explosive guns, then sufficient anti-loosening protection is achieved, but installation complexity and rig time increase significantly
Solution Approach 1:
The anti-rotation key is pre-installed in the pin connector at the factory before the pipe string is shipped to the drilling site. This preliminary installation eliminates the need for complex on-site installation tools and procedures, while ensuring the anti-rotation mechanism is properly positioned and functional when needed.
2Reliability
If anti-rotation keys with teeth that bite into connector members are used, then rotation prevention is effective, but axial compressive load and permanent deformation occur
Solution Approach 1:
Instead of relying on axial biting forces, the invention uses a circumferential engagement mechanism where the anti-rotation key's outer surface engages with a circumferential groove in the box connector. This transfers the anti-rotation function from the axial dimension to the circumferential dimension, eliminating permanent deformation while maintaining rotation prevention.
3Reliability
If drilling a hole for the locking member after pipe connection is made up, then anti-rotation capability is achieved, but metal shavings fall down the pipe string and create issues
Solution Approach 1:
The anti-rotation key and its circumferential groove are pre-configured in the connectors at the factory, eliminating the need to drill holes after pipe connection. This prevents metal shavings from falling into the pipe string while maintaining the anti-rotation capability.
4Reliability
If anti-rotation keys requiring on-site installation are used, then sufficient locking capacity is achieved, but valuable rig time is consumed
Solution Approach 1:
The anti-rotation key is pre-installed at the factory, transforming a time-consuming on-site installation process into a pre-prepared component. This eliminates valuable rig time while maintaining sufficient locking capacity through the pre-positioned key and groove engagement mechanism.
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 solution allows for efficient installation by the manufacturer, reducing rig time and axial load, while effectively preventing rotation of tubular members during unscrewing, thus enhancing the stability of threaded connections in hydrocarbon production operations.
Implementation Method 1
A biasing member urges the anti-rotation key into the grooves to provide resistance when rotating the connection in an unscrewing direction
Implementation Method 2
A recess in one of the pins or boxes allows the anti-rotation key to ratchet along grooves of the other of the pin or box as the connection is rotated in a make-up direction
Implementation Method 3
Normally, the operator relies on the friction of the made-up joint to prevent the threaded connectors from loosening while running the string into the well
Data Source
AI summary
A tubular member connection system includes a pin having a central axis, external pin threads, and an annular pin lip at a shoulder surface. A box has internal box threads and an annular box lip at an end surface of the box. The box threads are shaped to mate with the pin threads to releasably secure the pin to the box. A recess is formed in an outer diameter surface of the pin and extends in an axial direction from the pin lip. An anti-rotation key is located within the recess and has a row of teeth along an outer edge. A fastener retains the anti-rotation key in the recess. A circumferentially extending series of grooves on the box lip are sized to engage the teeth and resist a rotation of the pin relative to the box in an unscrewing direction when the pin is releasably secured to the box.