Verifying Regasification Plant
Availability For FSRU
The supplier delivers a regasification plant to be installed on an FSRU (Floating Storage Regasification Unit) vessel. As part of the contractual terms, the supplier needs to prove that the regasification plant can be expected to meet the strict availability requirements for the vessel. As a major source for FSRU downtime, the availability of the regasification plant is of outmost importance for the vessel operator to meet its contracted gas rates, thus avoid costly penalty fees.
RAM analysis is recognized as valid documentation of expected system availability, and the client requested Lloyd’s Register to do the work.
What Was Done
For the reliability modelling in Miriam RAM Studio, the supplier provided the necessary documentation (PFDs, P&IDs, functional descriptions etc.) of the regasification plant to be installed on the FSRU. The input on failure rates were largely based on industry sources (such as OREDA), that were further adjusted and agreed on with the supplier.
The study also considered the effect of spare part philosophy on downtime, as certain components can be very expensive and have a long lead time. If required, the model can be used to compare the effect on the availability on the FSRU of various design options of the regasification trains (for example 3x50% vs 3x33%) in order to increase availability or reduce capital expenditures.
Main result of the RAM analysis was a solid documentation of the expected system availability of the regasification plant and ranking of the major contributors to unavailability.
The regasification plant got an expected availability well within the contractually required 98%. Also, the breakdown showing which items contribute to system unavailability (below shown per item and per item class), was a crucial input to the spare parts analysis, comparing CAPEX with failures’ consequence in system uptime.
Furthermore, the FSRU operator later expanded the study to also include other critical equipment installed on the vessel. The obtained information about the expected production volume and downtime was then further used in contract negotiations between the FSRU operator and their client. In addition, the expected number of equipment failures allowed for effective spare parts planning and optimizing the operational expenditures.
This study was performed for a client by Lloyd's Register (www.lr.org).