254 SMO/1.4530 Alternative Material 1

[micalbrch]

Hello Colleagues,

We are a looking for an alternative material apart from Hastelloy C for 254 SMO. The part that needs to be manufactured is a 1.2 m long cylinder (ID 200 mm, OD 245). The raw material can be either casted or forged. Any recommendations?

 

[MikeMet]

You can consider VDM Alloy 1925hMo (UNS N08926) , AL6XN (UNS N08367), or URB66 (UNS S31266), VDM Alloy 31 (UNS N08031). All about the same chemistry and in about the saem price range.

 

[EdStainless]

and if the service temperature is between -40 and 600F you could use a 25 Cr duplex such as 2507 or 255 or Xeron 100.

You can also add N08925 to the above list. Every major stainless producer makes at least one 6% Mo grade.

make the part by press forming a piece of plate into a cylinder, weld with matching filler, solution anneal (2175-2200F), water quench, and pickle.

= = = = = = = = = = = = = = = = = = = =
Plymouth Tube

 

[micalbrch]

Thanks MikeMet and EdStainless. That's why i like this forum!

 

[strider6]

what kind of service and operating condition?

S

Corrosion & Rust Prevention Control

 

[micalbrch]

strider6: copper sulphide slurry, up to 2300 psi, pH < 2, 160 to 170 °F.

 

[ATsampalas]

254 SMO/1.4530 Alternative Material
Isn't there a mistake between 254 SMO and W=1.4530 ?
In my opinion, 254SMO is :
W=1.4547
UNS = S31254
ASME P Number = P 8.4
Conclusion : 1.4547 and 1.4530 are not in the same category

 

[metengr]

ASME P Number = P 8.4

You mean ASME P-No 8, Group 4.

 

[stanier]

Why not line a less costly material with PTFE or ECTFE?

 

[ATsampalas]

That is right 254SMO = P Nr 8 Group Nr 4 (ASME equivalent for plates : SA 240 UNS S31254)
Sincerely,

 

[micalbrch]

Dear All,

My thread is a little bit old and we chose 1.4557 as an alternative in the meantime. No idea what UNS no. that is. But the chemical composition is basically identical to 254 SMO and we get this material approved by our client, too.

stainer: We use this cylinder as a cylinder liner. That means there is a piston moving inside. That's why we cannot coat it.

 

[ATsampalas]

Dear Mr Micalbrch,
The following is only for technical information.
As previously mentioned, 254SMO is W=1.4547
Here are the main chemical analysis differences between
W=1.4547 and W = 1.4530
Sincerely,