Lloyd’s Register’s FOBAS (Fuel Oil Bunkering Analysis and Advisory Service) issued an alert warning that recent bunker samples in port of Houston, ordered as ISO-F-RMG380 grade, showed viscosity significantly above the specified limit of 380 cSt.
Specifically, the viscosity results ranged from 781 cSt to 818 cSt.
This follows another same warning earlier in October, concerning several bunker samples at port of Antwerp, ordered as ISO-F-RMK700 grade, for which, however, viscosity also significantly exceeded the specified limit of 700 cSt. The viscosity results of these fuel samples range between 750 to 765 cSt.
The use of high viscosity fuel depends on the ships’ machinery systems’ capacity to achieve the required temperatures for correct transfer/ injection viscosity. Fuel injection temperature, however, should not be allowed to rise above 150 deg C. Above average CCAI would mean additional attention should be given to the engine settings for optimum combustion performance.
“If your ships are planning to bunker at this port we recommend that suppliers are advised of your concerns regarding the viscosity of the fuel and that they provide you with additional reassurance that they will meet the ISO 8217 requirements for the grade ordered,” FOBAS advised.
Additional attention should be given to the collection of the bunker samples. It should be ensured that all parties have witnessed the sampling process and that the supporting documentation includes records of all the samples considered representative of the fuel as loaded.
