C- 1/2 Mo Availibility C- 1/2 Mo Availibility SnTMan (Mechanical) (OP) 29 Dec 16 16:44 Working a proposal for replacement of an old S&T exchanger, materials as noted. I've not dealt with this stuff before, so can anyone tell me, in general is this stuff available? Usual product forms, plate, pipe, forgings, tubes, B16.5 flanges. TIA, MIke The problem with sloppy work is that the supply FAR EXCEEDS the demand RE: C- 1/2 Mo Availibility NBrink (Materials) 29 Dec 16 21:41 I'm sure it's around somewhere out there, but generally speaking, C-1/2 Mo has been replaced with 1-1/4 Cr materials due to HTHA concerns (the old Nelson Curves had a C-1/2 Mo line that's since been removed since there were enough failures below it). Have had serious problems tracking down materials for repairs to C-1/2 Mo vessels. Personally wouldn't even consider it an option for a new vessel. Nathan Brink RE: C- 1/2 Mo Availibility SnTMan (Mechanical) (OP) 29 Dec 16 22:07 NBrink, thanks, I'll alert the sales guys :) Regards, Mike The problem with sloppy work is that the supply FAR EXCEEDS the demand RE: C- 1/2 Mo Availibility weldstan (Materials) 29 Dec 16 23:49 These tubes can still be found in the USA. They are still used in boiler applications. RE: C- 1/2 Mo Availibility NBrink (Materials) 30 Dec 16 02:06 Ugh, why? 1-1/4 Cr won't be that much more, and will have higher creep strength and be immune to FAC... Anyhow, I've had a devil of a time finding plate... Nathan Brink RE: C- 1/2 Mo Availibility metengr (Materials) 30 Dec 16 14:18 C-1/2 Mo boiler tubes were commonly used in the boiler industry, and started from the oil field industry. However, this material fell out of favor with most because the C-1/2 Mo has been prone to graphitization failures in elevated temperature service. RE: C- 1/2 Mo Availibility SnTMan (Mechanical) (OP) 30 Dec 16 18:23 Actually there are two exchangers, almost identical designs, vintage mid 70's. Customer requests "Replace in kind", which means, no one ever knows exactly what :) These designs use several thicknesses of plate, from thick to thin, body flange forgings, B16.5 flanges, pipe and tube all from C-1/2 Mo. I am always leery about availability with materials I don't use all the time, after all there is a reason they're not common. I have run the designs as C-1/2 Mo, and am going to let sales & estimating know availability may be a problem. I would guess substitute materials will need to be approved by the customer. I'll let 'em have at and re-run the designs again later if needed. Thanks again, Mike The problem with sloppy work is that the supply FAR EXCEEDS the demand RE: C- 1/2 Mo Availibility weldstan (Materials) 31 Dec 16 15:12 Plate availability is a different problem. You can find high strength, Manganese - Moly plate but it might not be suitable for your design parameters. WBrink, I do not dispute your statement at all, only to indicate the availability of C-1/2 Mo and 1/2Cr-1/2Mo tubing which we have used in boiler repairs with like tubes.