The application of subsea technology to reservoir development has been accepted as a valid production solution despite the known effects on facility availability and on ultimate recovery. The primary causes of the reduced availability for subsea tree-based solutions are directly related to the differences between the facility designs. A topsides drilling unit provides simple and direct access to the well for purposes of well logging and other data acquisition, and well interventions to replace equipment.
Other benefits of surface tree solutions are related to ease of well testing and chemical treatments. These in turn simplify the hardware maintenance because the facilities can be inexpensively directly accessed. In essence, the surface access solution gives increased well recovery because maintenance and diagnostic investigations are based on existing infrastructure (a permanently mounted drilling rig).
The subsea industry shares a common feature with other, more traditional, industries like Energy and Rail: the occurrence of unplanned outages results in increased costs and reduced revenues in each of these industries; a condition-based planning approach is the more desirable solution. Rail and Energy industries have successfully evolved to solutions based on the use of contractual frameworks aimed at guaranteeing equipment availability and efficiency.
This paper will examine the applicability of condition-monitoring technologies to subsea infrastructure in the oil production industry. The paper will present relevant case studies from the Energy and Rail transport industries. It will describe data and information handling which are required to enable the full development of a qualified predictive maintenance tool for the oil industry, with the view of taking the oilfield towards a paradigm of a contractually managed asset with the goals of improving service life and availability.