Flange Corrosion

[jayager]

Please find the attachment and please provide your suggestion, whether the flange faces can be repaired by welding + in-situ machining or whether the flanges need to be replaced completely.

 

[ehbadger]

What class is the 4" flange? Hard to see from picture. How much thickness has been lost.

 

[NBrink]

You'd have to check to make sure you'll be over the minimum thickness, but just eyeballing it, looks like you could probably just take a skim cut on the 4" with no weld buildup. B16.5 allows a RF to go all the way down to FF if the flange is still above the minimum thickness.

As for that big plate flange? That's on you. I wouldn't be comfortable with weld buildup on something that thin, you'll never get it flat again. Probably take more time than replacing the flange anyhow...

 

[weldstan]

Can't tell from the photos as to the need to weld build up and re-machine. But you can do so if needed. It appears that the blind flange was much too thin and this caused a poor seal thus allowing the corrosion to occur.

 

[jayager]

Thank you for all the post

 

[engineermian]

I think this is not a high-pressure equipment, clean it and buildup the area by approved WPS, Smooth grind it and perform the dpt, and secondly verify the cover plate (Blind) from loss of thickness, if the thickness less than the required please replace only this cover in-kind.

 

[hyah001]

Hi, for sur we can not tell much more from the pictures ,may I suggest you to clean with any rust removal and abrasif fin paper 2000, as usual in order to proceed with new measurements
Hassan (Preservation)

 

[Sam7489]

Please refer ASME PCC-1 - Guidelines for Pressure Boundary Bolted Flange Joint Assembly.