Equivalent Spec

[metalguesser]

Hi All!

We are working on a job to make forgings to a GE spec BA50A420.
We are at a loss to understand to what standard spec, such as AISI,ASTM,SAE or UNS can this grade be purchased.
The percentage composition of key elements is as follows;
C 0.25% - 0.33% - Mn 0.20% - 0.80% - Si 0.35% max
P 0.012% max - S 0.010% max - Ni 2.50% - 3.50%
Cr 1.3% - 2.0% - Mo 0.20% - 0.70% - Cu 0.35% max
V 0.07% - 0.15%

Does anybody know the equivalent AISI, ASTM, UNS or SAE grade for this chemistry? Appreciate any help or pointers in this regard.

Thanks

 

[IRstuff]

Shouldn't you ask your customer?

Why would you have bid on a job without even knowing what you were delivering?

TTFN

FAQ731-376
Chinese prisoner wins Nobel Peace Prize

 

[dbooker630]

It may not be a standard spec, rather a 'designer' grade of steel. Perhaps one of your steel mill contacts can help. If the chemistry is not commercially available you will have to buy a significant amount.

 

[redpicker]

That looks like a chemistry spec for a large diameter rotor (or something similar) needing to be through hardened. I'd suspect there is a minimum hardneability requirement to the specification in addition to the chemistry limits. I say this because the allowable range of the hardenability elements (Mn, Cr, Mo) is very wide. The hardenability requirement may vary based on diameter. This way, the same chemistry specification can be used for a wide range of sizes, but for each size, the steel mill has the freedom to adjust the chemistry to meet the hardenability requirements depending on the relative costs of the applicable alloying elements.

It looks like modified versions of 4330V may meet.

rp

 

[micalbrch]

Good luck with that! I got mad a few years ago with something very similar (a GE material spec. that nobody could transfer to the common standards). I learned that Genium Publishing Corp. bought the copyright of the GE Engineering Materials and Processes Information Service (EMPIS) long time ago. Acc. to the Genium website (

http://www.genium.com)

they sell a software for 199 $ which allows you to find the correct material. I could solve my problem in another way. So, I do not know how good this software is. Give them a call if BA50A420 is listed and buy it if they confirm.

 

[metalguesser]

Hi All!

We intend to ask for deviation on the chemistry. There are a few more parts that require ASTM A470 in sufficient quantities and we have no problem with them. This is something that we are willing to accomodate if we find the standard composition (or slightly modified but available) so we can purchase it off the shelf from stock. As dbooker630 pointed out we can procure the steel from any standard steel mill but we need to buy one full heat and we do not need more than 20K lbs for this item. Even if we decide to buy the steel the turn-around time is minimum 8 weeks and we are not sure we'll consume all of it for we have never processed this grade of steel before. Thanks for all of your help.

We shall propose alternate chemistries and probably a couple more similar grades that are readily available and see how it goes.

As regards buying the software from Genium, is this software specific to GE specs or is it something that can be used to find equivalent grades of steel universally? If it is specific to GE specs, we are not sure if the purchase can be justified for a one time use. This may be a one time job for all we know. Thanks for letting us know of the software though.

Regards