The vessel is equipped with Windlass cum Mooring winches make PUSNES, type 220 HW & type 245 HW.
Customer reported that the Port forward windlass claw coupling had cracked and that the bearing bushes of the main shaft of Port & STBD mooring winches were damaged.
In-order to carry out this major windlass repair, usually shipyard facilities and yard crane is needed, among others to lift the main shaft (estimated weight 5 ton) so that the bushes can be replaced.
ALATAS has been informed by our customer that the vessel is on a tight schedule and cannot berth at a shipyard. Instead, the job has to be carried out at anchorage, at OPL (Outer Port Limit), and the time available is 3 days only. Normally we would have used the floating crane. But, since the floating crane rental cost is high if it is arranged at OPL, we proposed an economically viable solution. i.e. to lift-up the main shaft by using a ALATAS designed and specially constructed and modular A-frame, that can be assembled on board without lifting aid.
Following was the job scope carried out by our experienced deck machinery repair team:
All the tools, equipment and A- Frame items were shifted from midship location to windlass.
Assembled and Placed A-Frame on top of Fwd STBD mooring winch location.
Instructed ship crew to remove the wire rope from the STBD mooring drum.
Fabricated the special tools and jacking out the capstan using hydraulic jack and ‘A’ frame.
Removed winch end frame and mooring winch drum using ‘A’ frame, bushes were found to be totally damaged.
Cleaned and inspected the main shaft, drum housing and capstan.
Machinist brought the new bushes on board.
Alatas Machinist measured the main shaft and carried out machining of the new pre-fabricated bushes to final size
Installed the fabricated new bushes and mounting frame, and adjusted the alignment using filler gauge.
Installed back the capstan as well as the dismantled parts to the main shaft
Applied the grease to all greasing point.
Carried out function test and alignment check in the presence of superintendent, Chief Officer and Chief Engineer. The STBD windlass finally found to be in sound condition without any abnormal noise and vibration.
Thereafter, Proceeded to the Port side anchor windlass to replace the bushes and claw coupling.
Shifted the ‘A’ frame and tools to the port side windlass.
Upon dismantling the drum, found that claw coupling was fully cracked.
Removed the cracked coupling, cleaned main shaft and installed the new claw coupling.
Our machinist measured the main shaft and carried out machining of the new pre-fabricated bushes to final size and followed by installation of mooring drum.
Installed back the capstan and other dismantled parts to the main shaft.
Applied the grease to all greasing point and carried out function test in the presence of Superintendent, Chief Officer and Chief Engineer.
PORT windlass operation found to be satisfactory with smooth operation, there are no abnormal noise and no vibration.
Dismantled A – Frame, tools and other materials, arranged them properly for offloading.