Condition Performance Monitoring for Subsea: Experience and Value documentation From the Gjoa Field
Authors: Soosaipillai Clarence , Roald Per Kristian , Alfstad Dag , Aas Torgrim , Smith George , Bressand Jean-Yves 
Published: May 2013

On the Gjøa oil and gas field, the operator, GDF Suez, has installed a Subsea Condition and Performance Monitoring (CPM). The CPM system is designed to maximize production uptime and maximize asset availability. Access to qualified and continuously-updated knowledge about integrity of the subsea assets are of utmost importance for making the right decisions at the right time in terms of maximizing profitability of the reservoir development.

The CPM system collects all subsea data, both process and housekeeping data, in real time. It takes integrity monitoring beyond traditional key performance indicators (KPI) by taking a holistic approach and utilizing all available data and information, where design parameters, criticality, system experience and operating philosophy is modeled and built into what is defined as Technical Condition Index (TCI).

The TCI enables the user to detect problems from the large amount of subsea data available, and to determine how severely it impacts production and system availability. The technology utilizes existing instrumentation. By modeling each TCI, assigning weights, building the hierarchic model and defining the aggregation rules, the CPM system and service is encapsulating the in-depth knowledge about the subsea production facility, making CPM an excellent tool for decision making. Finally, both Operators of the field and the support team of the subsea contractor will, through online access to the same tool, jointly be able to take the best decisions for the maintenance of the field.

GDF Suez will explain the positive impact and their experience of using the CPM on the daily operations of the Gjøa field in the North Sea in terms of costs, technology understanding and productivity. Operational examples will be shared where the CPM played a key role.

Introduction

Condition and Performance Monitoring (CPM) is a system and service developed by FMC Technologies to meet the requirement for operational and maintenance excellence. A subsea system is a complex arrangement of components where the effect of faults may be difficult to trace back to the root cause. The location subsea makes any fault costly and difficult to correct. The limited availability can also be due to harsh environment which on the other side can be the reason for being subsea in the first place. It is also a fact that the subsea system provides a lot of information through instrumentation, flow and response during operation. This presents a unique opportunity to monitor and assess component health throughout the life of the field.

The CPM system combines continuous monitoring of the system with a historic database that will enable trends and deviations to be identified. The system will mainly provide the operator with a warning when components start to deteriorate but are still operating. This in turn will allow pinpointing problems and enable corrective action to be planned resulting in minimum disruption to the production. A remote functionality enables the operator to receive qualified support from FMC about potential need for maintenance.