One of the key elements of working with dynamic subsea cables is installing it onto a winch. This can be done in various methods, however, it is of utmost importance to execute the process correctly to prevent any potential damage. Your cables play a vital role in your operations, and safeguarding them from harm will help you avoid significant costs and minimize downtime.
In this blog post, we cover what is necessary to during the installation process to ensure the longevity of your cables. This piece serves as a follow-up to our previous piece on 5 Costly Mistakes to Avoid When Handling Subsea Cables, which is dedicated to preserving the integrity of your cables. Discover valuable insights on handling subsea cables to achieve optimal performance.
Preparing the Cable and Winch Setup
Before beginning the installation, make sure to check that the cable ends are free from any entanglement or obstruction. Align the winch with the cable drum, keeping the pulling angle within 2 degrees. If space is limited, you can cautiously exceed this angle while minimizing the load. For armoured cables, spool them under tension. When setting up the drums, ensure the cable is wound from the top of one drum to the top of the other, paying attention to the lay of the outer serving of armour wire.
Connecting and Testing
Securely attach the termination to the drum before winding the cable onto the winch. When unwinding the cable, do so without applying tension until it reaches the winch, supporting the termination to prevent damage. Make sure the cable is properly supported by the drum barrel, avoiding exceeding the minimum bend radius or getting it pinched against any part of the winch structure. Attach the cable clamping arrangement and secure the cable tails to the winch. Double-check all connections for tightness and security. Test the winch to ensure proper functionality.
During the cable installation process, there are three key goals to focus on for ensuring longevity:
Goal 1: Resistance from Crushing by Following Layers
Eliminate gaps between coils and prevent crossovers or riding coils during cable winding. This ensures even distribution and proper support for the cable. Avoid compression and maintain alignment to protect the cable's integrity throughout its lifespan.
Goal 2: Good Structural Support for Following Layers
Apply sufficient tension during cable deployment to securely bed each coil down. Use approximately 10% of the cable's ultimate tensile strength (UTS) for tension after the first three coils of the first layer. This approach provides proper support and minimizes the risk of damage.
Goal 3: Minimizing Cable Slip during Deployment
Follow your comprehensive guide on "Reeling & Installation Instructions" provided by DeRegt Cable to minimize the risk of cable slip. If you have not received this guide, or have misplaced yours, don’t hesitate to reach out to the De Regt team to receive another copy.
Step 4: Control the Deployment, Tension & Inspection
To further enhance the longevity of your subsea cable, keep these instructions in mind whenever working with your cables:
- Deploy the cable in a slow and controlled manner, allowing it to extend to its full length under self-weight to minimize tension and stress.
- Set the winch to operate at normal operating tension after the cable is fully deployed to provide optimal support and control throughout its operational lifespan.
- Regularly inspect and adjust winding guides during the first deployment and subsequent recoveries to ensure proper alignment and identify any potential issues early on.
Key Takeaways
The longevity and performance of your cables are reliant on how well they are handled throughout their lifetime. By focusing on the steps outlined above, especially the fundamental goals, you can protect your investment and avoid costly repairs or replacements. Incorporating additional recommendations during the initial cable deployment will further enhance the lifespan of your subsea cables. if you suspect you may have damage, or need any guidance regarding your cables, don’t hesitate to contact a De Regt consultant. We are dedicated to helping you achieve success in your subsea projects.
