SA-995 grade 6A

[azizur447]

I work in a valve company. I received a MTR of materials SA-995 grade 6A from a supplier.Chemical composition & mechanical properties conforms with the above materials but PREN value not conform. Should the materials conforms with SA-995 grade 6A.

Thanks,

 

[metengr]

The PREN is a function of chemical composition. If the material fully meets SA 995 specification it should have a PREN value consistent with the chemical composition.

 

[pradipgoswami]

PREN values need to be reported-in MTR for Duplex castings.This and other testing requirements(ASTM G48...etc) needs to be specified in the the P.O.In absence of these being clearly written in the P.O the vendor may furnish details as required in SA 995.
Also if you look at SA 995, clause 5.1.6 Additional requirements provides the option of specifying additional requirements such as PREN.

I would suggest, if reporting PREN is mandatory as per the project specifications, then go back to the supplier, with the request for an amended MTR. It may cost you some dollars/euros, but would prevent hassles down the road.

Also I would feel the the content of the following article, though informative could be beneficial..

Thanks.

http://highlandfoundry.com/wp-content/uploads/2015/01/purchasingduplexcastings.pdf

Pradip Goswami,P.Eng.IWE
Welding & Metallurgical Specialist
Ontario,Canada.
ca.linkedin.com/pub/pradip-goswami/5/985/299
All provided answer are personal opinions or personal judgements only. It's not connected with any employers by any means.