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Belzona® 1212 Seals Propulsion Shaft Flange



Marine (MRNE)



Valves, Pipes and Fittings (VPF)


Customer Location:

Alaska, USA


Application Date:

January 2016


Application Situation:

Oil leaking from the flange when the propulsion shaft is spinning.



This flange is not designed to retain oil, but since there is a hose inside the propulsion shaft leaking oil, the need to seal off the flange to keep oil from being sprayed all over the engine compartment is very important for many reasons including personal safety. The second part of this problem is that the supply tank is over 40' above the shaft and cannot be shut off. This means the oil leak had to be stopped while under pressure.



Belzona 1212 

Belzona 9341 (Reinforcement Sheet)





Application Method:

The repair was carried out following a modified version of Belzona Know-How System Leaflet VPF-11. A hand grinder was used to clean and prep the steel. Belzona 1212 was mixed and most of its working life allowed to pass prior to application in order to stop the oil leak.


Belzona Facts:

Belzona 1212 is the perfect solution to this problem. There were limited abilities for surface prep, hydraulic oil is present as well as pressurized. The only other option was to keep this vessel on dry-dock long enough to disassemble and remove the entire propulsion shaft, find and fix the leaking hose, then re-assemble the entire unit. This procedure took a fair amount of time and patience dealing with the pressure, but with attention and persistence, Belzona 1212 stopped the leak and the repair was approved and the vessel was allowed to leave the dry-dock within the scheduled time.


Photographs Description

1. Showing the size of this oily flange.

2. First layer of Belzona 1212 with Belzona 9341.

3. Second coat of Belzona 1212.

4. Final application of Belzona 1212, all oil leaks stopped.

Case study pic one


 Case study pic two


 Case study pic three


 Case study pic four


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