steakman911
Petroleum
Good day all.
I am working as a CSA level II (CWI) Welding inspector on a SAGD site in N. Alberta.
I have noticed in the various areas of our plant a number of instances of: eg 1-2" 150# A105N RFWN Flg coupled to a similar sized flange of A182 Gr 316/316L RFWN flg. The gasket used is a fairly common and quite typical (on this site), type: 316L SPWD inner/outer ring. The bolting material is usually either B7 / B7M type with corresponding 2H / 2HM nuts and at other times there is SS steel bolting...none of the bolting is isolated from its dissimilar mate so to speak.
With what little knowledge I have on galvanic corrosion, IMO these connections present a possilblity of corrosion when there is an elctrolyte present.
I would be curious to know what limitations ASME may have (if any), on this type of connection as well as the potential for corrosion. There are various fluids being transported through these connections: Glycol, Brine, Bitumen among others.
To me and using common sense, there must be some sort of isolation present. As an analogy, it's no different if one has an RV and never uses or replaces the Anode...say goodbye to your hot water tank.!
But is there somewhere where this is stated categorically.?
(a Nace course or two is on my to do list within the next 12 mo.)
Thank you,
TxG
I am working as a CSA level II (CWI) Welding inspector on a SAGD site in N. Alberta.
I have noticed in the various areas of our plant a number of instances of: eg 1-2" 150# A105N RFWN Flg coupled to a similar sized flange of A182 Gr 316/316L RFWN flg. The gasket used is a fairly common and quite typical (on this site), type: 316L SPWD inner/outer ring. The bolting material is usually either B7 / B7M type with corresponding 2H / 2HM nuts and at other times there is SS steel bolting...none of the bolting is isolated from its dissimilar mate so to speak.
With what little knowledge I have on galvanic corrosion, IMO these connections present a possilblity of corrosion when there is an elctrolyte present.
I would be curious to know what limitations ASME may have (if any), on this type of connection as well as the potential for corrosion. There are various fluids being transported through these connections: Glycol, Brine, Bitumen among others.
To me and using common sense, there must be some sort of isolation present. As an analogy, it's no different if one has an RV and never uses or replaces the Anode...say goodbye to your hot water tank.!
But is there somewhere where this is stated categorically.?
(a Nace course or two is on my to do list within the next 12 mo.)
Thank you,
TxG