QSHE Bulletin Vol.26

Accidents, Causes & Preventive Measures Volume 26 9 31st March 2014 Spring Wires parted due to Rough Seas Boiler tripped M/E Starting Failure What happened? As a vessel conducted a try-out of Emergency Local Manoeuvring system, the M/E failed to start on air. On investigation, it was found that one of the Control Air Lines was punctured due to vibration, between a pipe and a supporting brack-et. The pipe was replaced with a new fabricated pipe. Cause: The pipe material was worn out due to gen-eral wear and tear caused by sustained vibration. Countermeasures: All control pipe lines with sup-porting brackets were checked for any damage and proper tightness. Lead plates were inserted be-tween the supports and pipes wherever needed. What happened? During a cargo discharging oper-ation the No.1 Aux Boiler, which was running on IGS mode supplying IG, was tripped on the Second Air Pressure Low. Immediately the IG mode was changed over to No.2 Aux Boiler, while the No.1 boiler was firing on the Slave Mode with a low load below 25 per FO flow. A few hours later, as the load on boiler was in-creased, the No.1 Boiler crossed the 25 per FO flow line, and tripped once more. During a trouble-shooting investigation, which took place after the boiler had been restarted, it tripped again. Although the remaining cargo work finished without another trip of the boiler, 4 hours after completion of the work the No.1 Aux Boiler tripped again during re-starting at 15 per FO flow. Eventually, the No.1 Aux Boiler was shut down. Cause: A small amount of water was found in the transmitter line of the differential pressure transmit-ter, which issued the secondary air pressure to the Aux Boiler. Countermeasures: The connection lines for differ-ential pressure transmitter are to be regularly air blown during boiler routine mainte-nance. What happened? An LPG Carrier engaged in dis-charging cargo operation, alongside with the pier with 4 head/stern lines, 2 breast lines and 2 spring lines on the starboard side. Due to a wave and strong swell the ship rolled and pitched vigorously, and that momen-tary excessive strain parted two of the forward lines. Cause: The forward springs were stressed as the tide was going up, then a strong wind, of force 8 to 9, swayed the vessel, resulted in the excessive strain on the mooring wires. The proper care and attention to the forward spring lines’ tension in such going-up tide would have prevented the occurrence. Countermeasures: Extra cautions, such as to syn-chronise the cargo operation progress with the tidal information sheet, to keep 20 cm slack at one time for avoiding excessive stress, and to check the line ten-sion during the patrol, etc., are required according to the weather condition in port. The company circulated this incident report across the fleet to remind the im-portance of keeping adequate tension of mooring wires (lines) when the vessel is alongside port. Tail-rope side Drum side Mooring Line severed What happened? During the mooring operation at a discharging port, a VLCC sent out the head line (a dyneema rope) for No.1 Mooring Buoy to a mooring boat. The rope became tangled with the propeller of the mooring boat, thus unable to proceed. The vessel sent another line to another mooring boat, in order to carry on the operation, and fortunately the mooring operation was completed without delay. However, they couldn’t loosen the rope from the propeller, it was sev-ered by the order of the berth master. Cause: The rope, partially floated on the sea, was blown by the wind. Although the vessel’s crew was sending the rope following instructions from the crew on the mooring boat, it might have been sent out too long. Countermeasures: All deck staff were reminded to carry out the mooring operation following the instructions of terminal staff. However, if they detect anything doubt-ful or unsafe in those instructions, it shall be immedi-ately reported to the master and the work shall be sus-pended until the safety is confirmed. In the pre-operation meeting, all conditions including weather, terminal’s requirements and their procedures, shall be duly confirmed by all deck officers and crew.