RLWI （Riserless Light Well Intervention） technology has the advantage of utilizing a special subsea lubricator to perform intervention activities in water depths of up to 1,200 m without the need for the marine rise...RLWI （Riserless Light Well Intervention） technology has the advantage of utilizing a special subsea lubricator to perform intervention activities in water depths of up to 1,200 m without the need for the marine risers. Utilizing the technology, oil companies have been able to save up to 50% on the intervention costs. However, in the last five years, it has seen up to 25% downtime due to waiting on weather （wow）. Thus, in this manuscript, it is attempted to identify the critical elements of the module deployment system and analyze their significance in the objective of raising the operational weather limit. Critical failure modes were found to be failure of crane wire due to excess loading, failure of the lower cursor system due to the impact loading and clashing of the module with the moonpool walls. Analysis of the module deployment system against these failure modes was ensued by using Orcaflex. The results showed the moonpool sea state to be the defining parameter. Although, changing moonpool dimensions affect hydrodynamics positively, however it＇s significance is small due to dependency on the vessel＇s breadth. Based on these results and the available data for the analysis, a recommended system particular was tested. Significance improvement, in lowering the risk of failure was observed.展开更多
文摘RLWI （Riserless Light Well Intervention） technology has the advantage of utilizing a special subsea lubricator to perform intervention activities in water depths of up to 1,200 m without the need for the marine risers. Utilizing the technology, oil companies have been able to save up to 50% on the intervention costs. However, in the last five years, it has seen up to 25% downtime due to waiting on weather （wow）. Thus, in this manuscript, it is attempted to identify the critical elements of the module deployment system and analyze their significance in the objective of raising the operational weather limit. Critical failure modes were found to be failure of crane wire due to excess loading, failure of the lower cursor system due to the impact loading and clashing of the module with the moonpool walls. Analysis of the module deployment system against these failure modes was ensued by using Orcaflex. The results showed the moonpool sea state to be the defining parameter. Although, changing moonpool dimensions affect hydrodynamics positively, however it＇s significance is small due to dependency on the vessel＇s breadth. Based on these results and the available data for the analysis, a recommended system particular was tested. Significance improvement, in lowering the risk of failure was observed.
