Considering fuel oil system, annual surveys of machinery spaces include verification of integrity of jacketed high pressure fuel injection piping systems and shielding of flammable oil piping system together with examination of remote operating of quick-closing valves, fuel/transfer pumps and ventilation fans. Spot testing of functions is included. Stand-by start of pumps will be tested. //DNV-RU-SHIP Pt.7 Ch.1 Sec.2.3

During renewal surveys performance test of fuel piping may be required. Internal examination of fuel/diesel oil tanks in engine room/machinery spaces is mandatory for at least one tank after third renewal survey (age of ship 10 and above). For fuel/diesel oil tanks located outside machinery spaces the internal examination requirement starts at second renewal survey (age of ship 5 years) and increases with the age of vessel. //DNV-RU-SHIP Pt.7 Ch.1 Sec.4.2.1
Settling tanks and daily service tanks for fuel oil shall be confirmed cleaned during the 15 months prior to the renewal survey. This may be credited based on relevant documentation provided. Opening up of tanks may be required as found necessary by the surveyor. //DNV-RU-SHIP Pt.7 Ch.1 Sec.4.3.3.1.12

Structural testing of fuel oil tanks is part of the renewal scope. I.e. head of liquid shall be at the highest point where the liquid will rise under service conditions and the tank boundaries will be inspected externally for leakage and deformations. A pressure test confirmed by master may be accepted as well. //DNV-RU-SHIP Pt.7 Ch.1 Sec.4.2.1

Heat exchangers are subject to visual inspection by opening up fully or partly as deemed necessary by attending surveyor. Visual external examination with performance test and verification of last overhaul is accepted for pipes, valves, filters, pumps and pump drivers is sufficient. Opening up can be required by attending surveyor if any deemed nec-essary. //DNV-RU-SHIP Pt.7 Ch.1 Sec.4.5
Note that additional class notations such as Clean, E0 and different fuel type related notations will give additional survey requirements.

Last modified: Thursday, 13 April 2023, 11:50 AM