The majority of the cases involved engine breakdowns – some with subsequent grounding or collision and the more severe also leading to pollution or even total loss of the vessel. The risks involved in some repair or maintenance operations are not always readily identifiable. Potential risks may be overlooked due to the apparent simplicity of the work due to be carried out and the consequences may be that proper preparations are not made and the necessary precautions not always implemented.
The purpose of this circular is therefore to highlight the importance of proper planning, co-ordination and follow-up before, during and after a period of repairs.
There can be several reasons for a vessel suffering an engine breakdown shortly after a period with engine repairs. Some of the most common factors seen by Gard have been a lack of co-ordination and follow-up meetings on the progress of the repairs by the shipowner and the yard’s ship repair manager, poor workmanship and qualifications of the repairer, e.g. when using sub-contractors, and unclear allocation of responsibilities and contractual issues between the shipowner and the yard.1 Time pressure from the owner or charterer, reuse of old spare parts together with long delivery times of new spare parts or the fact that spare parts have not been ordered at all, have in many instances had a negative impact on the end result.
Modification of the lube oil system
In one Gard case the lube oil system to the main engine had been modified by the shipyard. It was later revealed that the inside of the new piping had not been treated by acid pickling and flushing to remove scale and welding remnants. Debris from the inside of these pipes was deposited in various bearings when the engines were started upon departure from the shipyard. Increasing the engine load destroyed the bearings, and caused the crankshaft pins and bearings of the main engine to overheat. The modification work was an additional task and was not part of the detailed repair specification made available to the yard prior to the dry-docking. This resulted in unclear instructions to the yard and basic elements of the installation process were overlooked. The vessel suffered an engine shut down and almost drifted ashore.
Malfunction of the thruster
In another Gard case a vessel experienced problems with the pitch on one of its thrusters. Hydraulic filters were checked and a gel-like substance was found. During analysis of the substance, plastic materials were discovered. It later became evident that the cause of the damage could be traced to the previous dry-docking period where the thruster had been serviced by the manufacturer. When the shipyard fitted the lower unit of the thruster, the protective plastic wrapped around the exposed blank steel was not removed. Over time the plastic loosened and was ground between the moving parts to small pieces of plastic which penetrated all lines and controls causing a malfunction. The incident resulted in another off-hire period in dry-dock rectifying the problem.
Fire in the engine room
In a third case the fuel pumps of the vessel’s auxiliary engines were dismounted and brought ashore for overhaul. During a routine inspection after the vessel was put to sea, the duty engineer discovered a fuel leak from one of the fuel pumps. The load was taken off the generator from the main switchboard and a normal stopping operation was carried out. During the automatic switching process from HFO to MDO the corrosion plug in the leaking fuel pump exploded, which in turn led to MDO being flushed over the exhaust channel and igniting. The burning MDO spread across the upper platform and thereafter under the floor plating. After completion of casualty inspections it was discovered that the yard had not replaced new corrosion plugs as required. No follow-up meetings on the progress of the work and quality checks had been performed during the stay at the yard.
The time available to prepare the vessel following a period of maintenance, and get her back in operation can be limited, and the refitting of removed insulation mats or spray shields is often left for the crew to complete during the voyage. According to SOLAS Ch.II-2/Reg. 4.2.2, all surfaces above 220° Celsius must be insulated or protected in order to prevent ignition by flammable liquids.2
Preparing a vessel for a period of repair or dry docking involves quite a lot of work and co-ordination for those on board, as well as for shore based staff such as fleet managers, superintendents and purchasing department. Preparation in the form of planning as well as follow up during and after a period of repair are key factors in a successful dry docking or yard stay, particularly in connection with major engine overhauls.
We would like to emphasise the following recommendations :
The risks involved in specific repair or maintenance operations are not always readily identifiable and potential risks may therefore be overlooked due to the apparent simplicity of the repair work. It is therefor recommended that a proper risk assessment is carried out prior to the repair work to ensure that sufficient preparations are made and necessary precautions are implemented.
Properly brief the engine room crew about the type and scope of maintenance to be carried out and their respective duties before entering the yard to ensure that everyone has a common understanding of the scope of work, including special challenges, critical measurements to be collected, how to correctly perform the measurements and interpret the results. Where the engine crew has not been briefed it is very difficult, if not impossible, to follow up the work carried out.
The vessel’s crew should have a certain “ownership” of the repairs and overhauls to ensure the required and sufficient quality. Regardless of who is carrying out the repair or overhaul (yard, sub-contractor or manufacturer) there should be at least one responsible person from the vessel following up each and every job.
Use the engine’s manufacturer to conduct major overhauls of main or auxiliary engines during a yard stay. Should it be necessary to use sub-contractors or the yard’s own repair teams, it is preferable to use the engine manufacturer’s representative to supervise the overhaul.
Allow sufficient time to carry out test runs or sea trials after the completion of any engine repairs. It is much more cost effective and saves time to discover problems before leaving the yard, than if a breakdown occurs once the vessel has left the yard.
To avoid misunderstandings, ensure that all involved parties have a common understanding of the contractual agreements between the repair yard and the shipowner.
Dry docking and any major repairs to a vessel are expensive for the shipowner. Many of the costly incidents and time consuming disputes could have been avoided if proper planning and preparations had been carried out prior to the period of repairs, and if the necessary test runs or sea trials had been carried out after completion of repairs.