A Feasibility Study on Condition-based and Predictive Maintenance at Ula Gas Upgrade: Status mapping, analysis of potential and framework for implementation

Abstract

The oil and gas operators across the Norwegian Continental Shelf have entered a phase where over 50% of the fixed installations offshore have passed their expected lifetime. With aging facilities and extended life of production comes a higher demand for maintenance. Today, many of the older installations lack data to forecast maintenance, technical competence has been lost over the years regarding old equipment and new standards and regulations are affecting the operational requirements. The Ula asset, operated by Aker BP ASA, is one of the assets that has passed the expected lifetime limit. Ula is an old asset and is believed to have little to zero predictive maintenance associated with the equipment on the offshore installation. Therefore, it would be interesting to explore possible condition-based and predictive maintenance opportunities at Ula, more specifically at the Ula Gas Upgrade (UGU) module.

In this thesis, the purpose is to get a clearer picture of the current opportunities for an increase in the use of condition-based and PdM programs in the UGU module. UGU was selected since this module is one of the newest ones installed at Ula and is believed to have the highest potential for implementation of condition-based and PdM technologies. Therefore, a complete overview of 6,599 UGU tags has been reviewed including current maintenance, existing condition monitoring and potential future PdM. Several Excel models have been developed during the mapping process to present the different equipment categories with associated equipment groups. The collected data presented in the Excel models are obtained from Workmate and reviewed in one-to-one workshops with discipline experts. The project group have also compiled a proposed systematic framework for digitalization for an offshore oil and gas asset, with a simplified step by step approach.

From the mapping process and workshops, a total of 20 potential use cases for condition-based and PdM has been identified and created. The findings indicate that the maintenance performed at UGU today, is mainly condition-based and consists largely of different degrees of manual condition monitoring and assessments within fixed calendar-based intervals. Nevertheless, an unexploited potential of condition-based maintenance at UGU still exists regarding implementation of measures which allows condition assessments to change from being manual to automatic. This includes the use of automatic condition monitoring to reduce the need of manual condition assessments and maintenance. Apart from the use of predictive methodologies used by the inspection department, UGU does not have any further predictive maintenance possibilities today.