Condition monitoring for subsea processing plant

Abstract

Subsea implies unmanned work, harsh environmental conditions for the equipment operation and access difficulties in case maintenance or repair is necessary. Therefore operational conditions of subsea equipment should be monitored. Condition monitoring practice is widely used at onshore and offshore production facilities. Conditional monitoring of subsea assets is quite a fresh area. The way how the signal from the subsea sensor is transferred topside to the computer screen differs from the common practices. The main aim of this thesis report is to review condition monitoring techniques which are used in today’s subsea installations and propose reliable design of condition monitoring system for the subsea plant. Condition monitoring methods like vibration monitoring, sand monitoring for wellhead equipment and subsea separators, leakage detection, corrosion, erosion, water quality and process parameter monitoring are studied in this paper. Afterwards the design of conditional monitoring system is proposed including main subsea and topside equipment which participate in signal transfer from subsea sensor to the topside automation system. Design has to be reliable so that it would work under different circumstances. Moreover topside control system should incorporate condition monitoring functionality for more effective maintenance planning.