Windlass Repairs with Mobile A-Frame as Lifting Aid
The tanker ship is equipped with a combined mooring and anchor windlass, make Pusnes, windlass type HDU 30-03/ HDU 30-3, with a pulling capacity of 44.8 ton x 9m/min. The forward windlasses at port & starboard side had broken down due to damage to the claw coupling and worn out bearing bushes at the mooring winch main shafts. They were vibrating heavily and in urgent need of repairs.
ALATAS was requested to carry out this major deck machinery repair at anchorage, i.e. at OPL (outer port limit) in Singapore waters as afloat repairs. We were to completely strip down the mooring winch capstan, fabricate and supply new mooring winch drum bushes and replace them on both the Port and Starboard windlass,
The job was carried out completely without hot work and ALATAS own lifting aid was utilized. It is a modular constructed and mobile A-frame, suitable for a trolley & chain block with a lifting capacity of 5.0t. The A-frame was assembled on board and brought into position to lift the winch components via chain blocks & slings.
Following work was carried out:
Attended the vessel at Singapore anchorage and sailed with vessel to the OPL anchorage. Upon attending to the vessel, discussed with Technical Superintendent regarding the windlass problem and the tasks which need to carry out.
1. Prepared the tools and equipment and shifted to the FWD STBD windlass.
2. Assembled ‘A’ frame using by mid ship crane and shifted to the FWD STBD windlass.
3. Informed ship staffs to remove the mooring wire rope from the winch drum.
4. Fabricated the special tools and jacking out the capstan using by hydraulic jack and ‘A’ frame.
5. Removed winch end frame and mooring winch drum using ‘A’ frame, Found bushes were totally damaged.
6. Cleaned main shaft, drum housing and capstan and inspected.
7. Found main shaft diameter (ID 179mm) and pre-machine brass bushes (ID 200) were not match due to maker drawing shown that Shaft diameter 200mm and actual dimension was 175mm.
8. Informed Chief Engineer and Superintendent for the further discussion.
9. Alatas machinist arrived on board vessel together with new bushes.
10. Machinist carried out necessary measurement and fabricated new bushes (ID 179.70 mm and OD 200.70 mm).
11. Installed the fabricated new bushes and mounting frame, and adjusted the alignment using by filler gauge.
12. Installed back the capstan to the main shaft and all removed items. Applied the grease to all greasing point.
13. Carried out function test and alignment check in present of superintendent, Chief Officer and Chief Engineer. Found satisfactory with no noise, no vibration.
14. Proceeded to the Port side anchor windlass to replace bushes and claw coupling.
15. Shifted the ‘A’ frame and tools to the port side windlass.
16. Upon dismantling the drum, found claw coupling was fully cracked. Removed the defective coupling, clean main shaft and installed the new claw coupling.
17. Alatas machinist fabricated the new bushes and replaced the bushes. Installed back all parts as per original manner.
18. Applied the grease to the all greasing point and carried out function test in present of Superintendent, Chief Officer and Chief Engineer. Found satisfactory with smooth operation, no noise and no vibration.
19. Dismantled the ‘A’ frame and carried out housekeeping on the working area. All tools and Equipment were prepared for off- loading and transport back ashore.
Note: Used metal plates to shim the foundation instead of Chockfast.
Tanker Vessel in need of Windlass Repairs
Stbd winch drum
Stbd windlass view
Port anchor winch brake band
Modular A-frame on deck
A-frame shift to the FWD anchor windlass
After removing mooring winch brake band
Port winch claw coupling cracked
Mooring Drum removal, using studs, strong-back & hydraulic jacking
Port winch removing capstan
Pulling out the capstan
Port winch foundation choke fast base found broken