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Participant

Join Date: Sep 2014
Location: India, Mumbai
Posts: 1

H2 Max 4 PPM

09/13/2014 5:00 AM

What is the major difference between H2 max 4 ppm & Vacuum Degassing, this query is for plate as we want the plates to be Vacuum Degassed whereas we are offered H2 max 4 ppm, kindly provide us with the detailed expanation & oblige.

Also explain us the meaning of H2 max 4 ppm.

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Guru

Join Date: Mar 2007
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#1

Re: H2 max 4 ppm

09/13/2014 7:17 AM

For purpose steel plate will be specified usually by the intended use....Hydrogen content and other components will determine the suitability of the steel you are using.... High hydrogen contents are generally considered as detrimental due to the risk of flakes, bubbles and breakouts during casting as well as hydrogen embrittlement.... Hydrogen can nonetheless be removed by degassing of the steel.....

http://www.astm.org/Standards/steel-standards.html

http://www.saimm.co.za/Conferences/Slags2004/105_Dekkers.pdf

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Guru

Join Date: Oct 2008
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#2

Re: H2 max 4 ppm

09/13/2014 12:10 PM

For your purpose there is no difference.

H2 max 4, ppm means it is virtually hydrogen free.

It's a language thing, you can use it.

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Guru

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#3
In reply to #2

Re: H2 max 4 ppm

09/13/2014 3:51 PM

Well I think there are uses that require less than 4 ppm(parts per million).... What is the intended use of this steel..? ...and what are the specifications?....4 ppm is the stated hydrogen content and vacuum degassing is a process for removing hydrogen(or other gasses), usually from molten steel....Vacuum degassing is used to set the ppm at the specified level....

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Guru

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#4
In reply to #3

Re: H2 max 4 ppm

09/13/2014 4:12 PM

I understand degassing. I used to specify materials for satellites.

The OP is clueless, so providing detailed technical information is a waste of our time.

The information will not add any value to the final product. It will be up to the supplier to decode OP's requirement, not the forum.

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Guru

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#5
In reply to #4

Re: H2 max 4 ppm

09/13/2014 4:32 PM

Yeah that second part wasn't really aimed at you but more of an exploratory explanation to the op...I am quite sure you know all about material specifications....cheers

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Guru

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#6
In reply to #5

Re: H2 max 4 ppm

09/13/2014 4:42 PM

And I am sure that you are only trying to help the OP.

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