Riser Joint Coupling with Cam-Actuated Locking Segments
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In offshore drilling operations, connecting and disconnecting riser joints is hazardous and time-consuming, especially in deep water, due to the need for manual handling of bolts and screws, which exposes workers to injury and incurs high costs for moving and storing the riser.
Innovation Solution
The design features a riser joint with a pin and box configuration, where a cam ring moves axially to engage locking segments with a profile on the pin, creating a preloaded connection without the need for bolts or screws, and is operated by a handling tool that automates the locking and unlocking process.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If manual handling of bolts and screws is used to connect riser joints, then the connection can be made with simple tools, but workers are exposed to injury risk and the process is time-consuming
Solution Approach 1:
The patent replaces the manual mechanical fastening system (bolts and screws requiring wrenches) with an automated cam-actuated locking mechanism. The cam ring, when rotated by the handling tool, actuates cam surfaces that force locking segments into engagement with the pin profile, eliminating manual bolt tightening and associated safety risks.
Solution Approach 2:
The locking segments are designed to automatically engage with the pin profile when the cam ring is actuated. The cam surfaces guide the locking segments into their locked positions without requiring manual adjustment or multiple steps, making the system self-actuating once the cam ring is rotated.
2Strength
If multiple bolts spaced around the circumference are used to connect flanges, then the connection is secure, but the making-up process is time-consuming and labor-intensive
Solution Approach 1:
The patent merges the function of multiple circumferential bolts into a single integrated locking mechanism. Instead of tightening individual bolts around the circumference, a single cam ring actuation simultaneously engages multiple locking segments that distribute the connection force around the pin, achieving both secure connection and operational efficiency.
Solution Approach 2:
The connection system is segmented into multiple locking segments spaced around the circumference, each independently engageable with the pin profile. This segmentation allows the load to be distributed across multiple engagement points while being actuated by a single cam ring, combining the strength of multiple bolts with the efficiency of a single operation.
3Adaptability or versatility
If riser joints are pulled and stored in deep water, then the rig can be moved to new locations, but the cost increases significantly
Solution Approach 1:
The handling tool is designed to quickly actuate the cam ring and engage the locking segments before the riser joint needs to be pulled. This preliminary locking action ensures that the connection is secure and ready for immediate retrieval, minimizing the time the riser is in a vulnerable unsecured state and reducing the overall cost of relocation operations.
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 solution reduces the risk of injury to workers, speeds up the connection process, and lowers the cost of riser management by eliminating the need for manual handling and reducing the expense of moving and storing the riser in deep water.
Implementation Method 1
The locking element has an outward-facing cam surface, and the ring has an inward-facing cam surface that slides against the cam surface of the locking element as the ring moves axially to force the locking element to the locked position
Data Source
AI summary
An offshore riser system has riser joints, each having a pin and a box. The pin has an external grooved profile that is engaged by a locking element carried by the box of another riser joint. An actuating ring engages with the locking element to move it into the locked position. A retractable spider supports the string of riser while the new joint is being made up. A makeup tool on the riser deploying floor moves the ring relative to the locking element, causing the locking element to move to the locked position.