Asset type: Mobile Offshore Drilling Units (MODUs)
Project scope: Joint project to fit fibre optic sensors directly to the load bearing cylinders of Marine Riser Tensioners (MRT) to measure axial and bending loads in order to fully meet the requirements of API16Q.
Clients: Transocean (client) and Micron Optics (vendor and fibre optics consultant)
In a joint collaborative project between Transocean, Micron Optics and LR Energy, fibre optic sensors were spot welded directly to the cylinders of marine tension risers to measure axial and bending loads. The project, set up to help Transocean better meet the requirements outlined in the update of API16Q, or more accurately the API16Q Rf value (reduction factor), has produced real-time data results with the goal of reducing NPT due to unplanned maintenance.
Before fibre optic sensors were chosen as the definitive method, Transocean identified the following requirements:
- Obtain real time loads
- Obtain historical operational baselines
- Realise trends that point to potential failure
- Reduced non-productive time (NPT)
Following a series of meetings between Transocean, Micron optics and LR Energy, it was soon realised that the fibre optic sensors would be the most suitable solution as they are not only intrinsically safe (suitable for use in potentially explosive environments) but are easily installed and unobtrusive, allowing for minimal downtime during installation. They were then installed in September 2012 by LR Energy and commissioned in May 2013.
Since the sensors were implemented, Transocean has had access to a wealth of information including the ability to compare the previous hydraulic system parameters against the loads acquired from the fibre optic sensors allowing them look at trends and predict and implement maintenance plans accordingly.
The data acquired is more representative of the loads compared to previous methods, with Transocean commenting that “these types of load measurements have never been made before. We are extremely pleased with the performance of the system and the data we are obtaining”. This data has not only helped potentially reduce NPT on the rig, but also paved the way for Transocean to adopt a condition based maintenance and monitoring programme.
This project has since gone on to be nominated for this the Innovation Award at the ONS 2014 conference and paves the way for future projects utilising fibre optics to provide accurate, real-time measurements of other components both on offshore platforms and in various other industries.
You can find out more about this project and the technical specification in Technology Insight, our regular update on technology leadership.