Subsea Hydraulic Leakage Detection and Diagnosis

The motivation for this thesis is reduction of hydraulic emissions, minimizing of process emergency shutdowns, exploitation of intervention capacity, and reduction of costs. Today, monitoring of hydraulic leakages is scarce and the main way to detect leakage is the constant need for filling of hydraulic fluid to the Hydraulic Power Unit (HPU). Leakage detection and diagnosis has potential, which would be adressed in this thesis. A strategy towards leakage detection and diagnosis is given. The strategy defines three approaches, define an approach, explore the approach and propose a solution. Relevant instrumentation, both existing and additional instrumentation is discussed. Relevant methods towards leakage detection and diagnosis are presented. An overview of a bewidering amount of methods is given, and basics towards application. An example from pipelines of state-of-the–art leakage detection and diagnosis is also given. A solution proposal for a simple and available leakage method with fair detectability and limited diagnostics is proposed. There tends to be a connection between performance of application and complexity. For today’s solution it would be preferable to scarify some overall performance for simplicity, considering the alternative