Segmented Coiled Tubing With Ball-and-Socket Joints
Solution Overview
Problem
Traditional drillstrings face limitations in combining the strength of thick-walled rigid pipe with the rapid deployment and flexibility of thin-walled coiled tubing, as they require complex unwinding and bending operations and have material constraints on spool winding.
Innovation Solution
The self-assembling segmented coiled tubing system uses spring-loaded spherical 'ball-and-socket' joints to connect short, rigid pipe segments, allowing for flexible assembly and disassembly, similar to coiled tubing, while providing the strength of rigid pipe, and optionally using a snap ring for permanent locking.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If thick-walled rigid pipe is used, then strength is improved, but deployment complexity and time increase
Solution Approach 1:
The drillstring is divided into multiple short rigid segments (e.g., 6-8 inches long) connected by spherical joints, allowing the assembly to be coiled and deployed like flexible tubing while maintaining the strength of rigid pipe. The segmentation enables rapid deployment without requiring complex unwinding operations.
2Productivity
If thin-walled coiled tubing is used, then deployment speed is improved, but strength decreases
Solution Approach 1:
The system uses multiple short rigid segments connected by spherical joints, combining the strength of thick-walled pipe with the flexibility needed for rapid deployment. Each segment maintains sufficient wall thickness for strength while the segmented configuration enables coiled tubing deployment speeds.
Solution Approach 2:
The spherical joints provide dynamic flexibility between rigid segments, allowing the drillstring to be coiled and deployed rapidly while maintaining structural integrity. The joints enable the rigid segments to move relative to each other during deployment, providing the flexibility of thin-walled tubing without sacrificing the strength of thick-walled pipe.
3Strength
If traditional jointed pipe is used, then strength is improved, but device complexity increases
Solution Approach 1:
The spherical joint design replaces complex threaded connections with a simple ball-and-socket mechanism. The spherical geometry allows for easy assembly and disassembly while providing the necessary strength and flexibility. The curved spherical surfaces enable smooth relative movement between segments during coiling and deployment.
4Volume of moving object
If coiled tubing is wound tightly on spool, then space efficiency is improved, but deployment force increases
Solution Approach 1:
The segmented configuration with spherical joints allows the drillstring to be wound tightly on the spool while maintaining ease of deployment. The joints act as flexible connections that reduce the deployment force required compared to continuous tubing, while still allowing tight winding for space efficiency.
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 design enables a single system to transmit mechanical loads and torques efficiently, reducing deployment forces and extending the range of bending rates and mechanical load transmission, while maintaining the strength and flexibility of both traditional systems.
Implementation Method 1
spring-loaded spherical 'ball-and-socket' type joint
Data Source
AI summary
Self-assembling segmented coiled tubing is a concept that allows the strength of thick-wall rigid pipe, and the flexibility of thin-wall tubing, to be realized in a single design. The primary use is for a drillstring tubular, but it has potential for other applications requiring transmission of mechanical loads (forces and torques) through an initially coiled tubular. The concept uses a spring-loaded spherical ‘ball-and-socket’ type joint to interconnect two or more short, rigid segments of pipe. Use of an optional snap ring allows the joint to be permanently made, in a ‘self-assembling’ manner.