fisherman
Well-known member
They needed a crane in the bottom of the dry dock. I'm surprised they didn't use a dock crane (to drop the small crane in)
Crane a crane
- Thread starter fisherman
- Start date
fisherman
Well-known member
To pull the tailshaft apparently
sarabande
Well-known member
Gee, just to think of getting the alignment correct over that length ! Crane driver is earning his money !
andsarkit
Well-known member
Some people like to show off.
Farmer Piles
Well-known member
Those cranes at the docks don't have a very high lift capacity - around 10t I think. I would imagine the mobile crane is considerably heavier than that.
LittleSister
Well-known member
We have cranes in Norfolk!
wonkywinch
Well-known member
I always thought the national bird of Singapore was the crane!
rogerthebodger
Well-known member
The Blue Craane is the national bird of South Africa as seen dancing above
Refueler
Well-known member
19,000MT P Class Shell tanker, Hamburg Dry-dock..... 1978. I was 3rd Mate on her ...
She had failure of the Lignum Vitae sternseal and we limped at 4kts from West Africa to Hamburg for repairs.
Instead of removing rudder - they removed the prop ... dismantled the aft part of the steam turbine to shaft. Dismantled the shaft bearing holders at intervals along shaft (shaft runs through 2 large bearings set at positions along shaft).
They then cut a hole in hull side plating level with shaft ... pushed shaft FORWARD and to one side of turbine casing ... then back out through the hull plating hole. Once enough shaft was sticking out - like a gun out of Victory gunport - they welded the plating to the shaft !
Built gantry round it .. then ground the shaft where new sternseal would be installed ...
I did have a photo - but its been lost over the years ...
She had failure of the Lignum Vitae sternseal and we limped at 4kts from West Africa to Hamburg for repairs.
Instead of removing rudder - they removed the prop ... dismantled the aft part of the steam turbine to shaft. Dismantled the shaft bearing holders at intervals along shaft (shaft runs through 2 large bearings set at positions along shaft).
They then cut a hole in hull side plating level with shaft ... pushed shaft FORWARD and to one side of turbine casing ... then back out through the hull plating hole. Once enough shaft was sticking out - like a gun out of Victory gunport - they welded the plating to the shaft !
Built gantry round it .. then ground the shaft where new sternseal would be installed ...
I did have a photo - but its been lost over the years ...
Refueler
Well-known member
Ships shafts usually run in intermediate bearings along their length - not just supported at engine / sternseal ends. Its also of note that shafts only stay stationary when maneuvering (STOP command on Telegraph) or in Dry Dock. Usually even when moored / anchor - they engage turning gear which very slowly revolves the shaft to avoid it suffering sag ... if you see a light ship alongside - watch the prop and you will notice the very slow rotation ..
Its actually a significant issue after a ship comes out from layup. Many ships are restricted in RPM if not worked on to make sure shaft is OK. The seals also can be affected. I've sailed on ex-lay-ups - some were restricted to 70 - 75% shaft speed.