Replacing Hull Plating - Insitu? 1

[kjunedi]

All,
There are some leakings found on the hull plating of our FPSO (The leaking are due to severe local corrosion and located in the splash-zone area). We have plan to use MOBDOCK to do the refurbishment. However, before mobilizing MOBDOCK, I would like to ask to everybody in forum the following:
1. Is there any other alternative method for repairing/replacing hull plating insitu?
2. What about safety precaution for doing this job?
3.Is there any standard/regulation/Guideline from ABS for doing this kind of job?
Thanks

 

[netherhay]

The publication Marine Engineers Review published by IMarEST May 2005 contains an article on a Sandwich Plate System that might be of interest.

Try the IMarEST website:

http://www.imarest.org

 

[BrianBT]

It is very unlikely that ABS will get involved with the method of repair. There interest will only be in the quality of the finished product. ABS are unlikely to accept doubling even when fishplated.

You need to have a realistic assesment of the structural impact of the damage and the effects removal of plate sections will have. For this you should be in close cooperation with a Naval Architect.

It appears that you wish to do this afloat and are not considering the use of a drydock- this would of course expedite the repair and increase the safety factor significantly.

Is it possible to ballast the ship to give trim and/or list giving clearance above the water level. Indoing this it may be possible to stage the area so long as suitable arrangements are made against possible flooding

 

[ssreese1500]

1. what is the material of the hull

2. what is the size of the section to be replaced

3. how far from the water is it, and how do you plan to access both sides?

 

[liviebudgie]

Done this more than once because of battle damage.
We build a coffer dam with rubber seals around the edge, fabricated to the curve of the hull.
water pressure helps hold the dam in place although this can be helped with canvas and ropes.
Pump out the dam with suitable pumps and leave open tooped for ventilation.
This can be used for welding and or GRP.
To get you home a plate can be "nailed" to the hull with a seal sandwiched between. Ramset nail gun helps here.
Bets repair is still dry dock as preservation determines lenght of repair life as much as quality of welds, poor painting means rust in days.

 

[MASE81]

How about a report back on what system you ended up using?

 

[seatrendgokhan]

kjunedi

Could you please clarify the followings asked by;

ssreese1500 (Marine/Ocean) 8 Nov 05 16:07
1. what is the material of the hull

2. what is the size of the section to be replaced

3. how far from the water is it, and how do you plan to access both sides?


GOKHAN
Naval Arc.& Marine Eng.