21 October 2016 | C16032
Following a recent Port State Control (PSC) inspection, four deficiencies have been imposed that resulted in the detention of the vessel. Dromon wishes to draw attention to these detainable deficiencies to avoid re-occurrence.
Ship Owners / Managers / Operators | Surveyors
Oil Mist Detector for Main Engine found inoperative
Following the PSC inspection it was noted that the oil mist detector for main engine was inoperative. The vessel’s oil mist detector is fitted to detect the oil mist concentration in the crankcase and to give early warning. It is designed to prevent the primary explosion and its alarm setting is 2.5% of the lower flammable limit.
It is important to carry out routine maintenance of Oil Mist detectors to prevent false alarms. The sensitivity of Oil Mist Detector should be checked on a regular basis as per below checklist:
- Daily check alarm system.
- Check for any abnormal alarms in the panel.
- Detector head cleaning.
- Make sure fans is working.
As all the samples contain a small amount of mist, the lenses and mirrors tend to get dirty and thus require periodic cleaning. The extractor fan and the rotating valve should be checked to avoid chocking of a particular sampling tube. The sampling tubes that connect cylinders to the OMD should not have any loops and also shouldn’t be of length more than 12.5 meters.
How will you take action when oil mist detector alarm is on?
Step 1 – Inform to chief engineer
Step 2 – Inform bridge, take the permission to stop the engine
Step 3 – Gradually reduce the engine and then stop.
Step 4 – Cool down the engine.
Step 5 – Check the inside parts of the crankcase inspection.
Step 6 – Make necessary repair
Step 7 – Reset Oil Mist Detector and start engine
Engine room ventilation not as required
During the PSC inspection it was noted that the ventilation gratings of engine room were found damage and/or holed. Special attention should be paid to the engine room ventilation in order to ensure trouble free operation of all equipment.
Engine room ventilation systems consist of both intake fans, which insert combustion air and cooling air, and exhaust fans, which pull out cooling air only. In case the temperature in the engine room rises, the exhaust fans start to pull out cooling air. Consequently, the resulting depression in the engine room ramps up the intake fans.
Proper condition of engine room ventilation system
Emergency lighting not properly maintained
It was noted that the emergency lighting at every boat station on deck and oversides were found in bad condition. Some lights were found broken, one heavily damaged and some other blocked. It is important that regular checks and periodic servicing and maintenance is carried out on board and any defects to be repaired and/or replaced.
Upon check and test, all safety lighting units will have a visual indicator which, when functioning normally, will be illuminated. This indicates that the unit battery is receiving a constant electrical charge from the mains. This indicator lamp should be checked daily for operation. Any defects should be reported immediately for corrective action.
Jacketed high pressure lines and oil leakage alarm for main propulsion engine found inoperative
Regardless of the system selected, little additional maintenance or periodic inspection is required to keep the jacketed fuel lines in proper working order. However, jacketed pipes should be inspected regularly and any drainage arrangement which may have been disconnected for maintenance purposes should be refitted on completion of the task.
The general condition of the system will be checked during annual surveys with special attention to be paid to any possible leaks from the high pressure pumps.
Proper condition of high pressure lines
Sample of jacketed pipe
The leakage collector lines are often located behind the fuel pump covers and leaks may be difficult to detect. In cases where the appearance of the engine indicates a fuel-oil leakage, it should be verified that the fuel-oil collector lines are in place, connected and open. Since it is highly likely that the leak-off lines leading to the tanks will be clogged with sludge from minor oil leaks, it is extremely relevant to check these and verify that they are clear in order to facilitate safe containment in the event of a leak.
Verifying the jacketing of high-pressure fuel pipes and testing the leakage alarm are important elements of annual surveys, and the crew must at this time demonstrate the fuel-oil leakage alarm. Any deficiency must be rectified before leaving port.
If there is any doubt as to whether the relevant pipes are double-walled or not, part numbers can be verified against drawings available on board and/or space parts can be checked.
Surveyors must take note on the above detainable deficiencies and give special attention during forthcoming class and statutory surveys, irrespective of scope.
Ship Owners / Managers / Operators are encouraged to inform Masters and take corrective actions if necessary. For further assistance please contact DBS Head Office.