vacuum degassing and casting products 1

[Chumpes]

Dear all,
We have the requirement of specifying steel products (seamless pipe, forgings, castings, plates, tubes) with a vacuum degassing (VD) step during the steel making process.
In my opinion, final product forms are obtained by shaping (or melting for casting products) steel ingots that should have been produced with a vacuum degassing step in order to reduce porosities that may be induced by residual hydrogen in steel.
I have a couple of piping material suppliers who state that they are not able to comply with such requirement... on the contrary, suppliers of plate materials never complain about it.

My questions are :
Is it practicable to order steel castings, forgings and seamless tubes-pipes with the requirement of these steel products having a vacuum degassing step during the steel making process ? is this something very exotic or commmon ?
Is this information on the steel making practice (ingots produced with VD or not) saved during the overall manufacturing route from original steel making of ingots to the final product form ?

thanks
regards

 

[EdStainless]

If you want VD steel spec if and just know that it will limit your supplier base.
There are other ways to make high quality steel.
Most people prefer to specify the results, inclusion rating, final product NDT, and such and not specify the production route.

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P.E. Metallurgy, Plymouth Tube

 

[Dhurjati Sen]

Dear EdStainless,


Anything better than VD in particular? Adding fluxes like calcium treatment?

Regards.

DHURJATI SEN
Kolkata, India

 

[MagBen]

VD seems an old term. Nowadays, you can specify the melting type, JK test, ultrosonic test etc. which are much specific and better requirements