Inconel 625 bhn??

[Henderson17]

Dear material people,

We have ordered a carbon steel vessel with weld overlayed in inconel 625 and we have been asked by our client to ensure that the material does not exceed 200BHN.

Should this pose any problem??

Our fabricator is asking for us to request a concession on the hardness because they are worried about achieving it.

Any help on this matter is much appreciated.

 

[metengr]

We have ordered a carbon steel vessel with weld overlayed in inconel 625 and we have been asked by our client to ensure that the material does not exceed 200BHN.

Should this pose any problem??

I checked in my Avesta Welding Manual, and for covered electrodes (Avesta P625), and for their MIG solid wire (P12 product), they provide a typical hardness for as-deposited weld metal of 220 Brinell, for both.

So, to settle this, I would have a carbon steel coupon run with the 625 overlay, have the coupon cross sectioned and have a hardness traverse across the thickness of the overlay. This is the real proof between 200 Brinell versus 220 Brinell in published literature.

 

[SJones]

What is the client's specific point of requesting a hardness limit in the 625 layer? Did they mean the HAZ of the carbon steel substrate?

Steve Jones
Materials & Corrosion Engineer

http://www.pdo.co.om/pdo/

 

[castmet13]

I assume that you are dealing with potential H2S issues? Sour gas or similar? this sounds like a flowdown of MR0175...is that it?