Offshore Piping Refurbishment Approach - High Corrosion on Piping & Valves

[alhameli]

Service Fluid: Closed Drain Fluids(H2S)
Temp: 140F
Pressure: 900 PSI
Material: CS/Incl625

[image

https://files.engineering.com/downl...file=Corroded_Valve_-_Closed_Drain_System.png

]

Service Fluid: Open Drain Fluids (Well fluids, oil, sea water)
Temp: AMB
Pressure: ATM
Material: CS/Incl625

[image

https://files.engineering.com/downl...3&file=Corroded_Valve_-_Open_Drain_System.png

]


I am facing a challenge of preserving both systems in live conditions. We have decided to go with sponge blasting on piping with sufficient wall thickness and bristle grinder for piping with scab corrosion.

For the valves/flanges/bolts, is there a safe way to clean/blast the surface and repaint or stop the corrosion by other means?
Is there a better approach for piping than the ones suggested above?

UT data is available for majority of piping.

 

[LittleInch]

Well it looks bad, but in reality there is a lot of metal there on the flanges and valves. The pipe needs to be treated with more care for sure, but what you propose appears to be good to get a decent surface finish on which o apply a good quality primer and top coat.

Try to avoid wire brushes and other cleaning which just polishes the surface as this results in poor adhesion of the primer. Blasting works as the final run, but grinding and sanders / flaps tends to polish the surface.

Check what surface finish you need for whichever coating system you plan to use.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[SJones]

https://stopaq.com/wp-content/uploads/2022/07/PDS-Stopaq-4200-Filler-V7-EN.pdf

https://publishing.energyinst.org/t...of-coatings-for-external-corrosion-protection

https://www.linkedin.com/pulse/fabric-maintenance-asset-integrity-lee-wilson/

Google "offshore fabric maintenance"

Steve Jones
Corrosion Management Consultant

http://www.linkedin.com/in/drstevejones

All answers are personal opinions only and are in no way connected with any employer.

 

[alhameli]

Thank you both