HIC

[aiwa7777]

We are using a HIC tested plate for a pressure vessel.

Are there any special requirements for welding and welding procedure from HIC point of view ?

Is there such a thing called "HIC Tested Welding Procedure" ?

Thanks in advance

 

[SJones]

Generally not for the welding of pressure vessels as there is no indication to do so in NACE TM0284. It is assumed by many that welding does not produce any metallurgical changes that would lead to increased HIC susceptibility in material that has already been tested.

Steve Jones
Materials & Corrosion Engineer

http://www.linkedin.com/pub/8/83b/b04

 

[weldtek]

Agree with SJones but hardness is generally a concern so be sure you're using consumables, and employing techniques including preheat as necessary, to stay withing the allowable limit. Client specs often dictate acceptable hardness levels as does NACE and in the past I've had to qualify procedures by testing for hardness only.

 

[aiwa7777]

Thank you Mr. Jones and Weldtek for your responses.
Can HIC occur in the weld metal ? If yes, then what can be done to prevent it?

Thanks again.

 

[SJones]

If you are a welding engineer - Yes. If you are a corrosion engineer - No. Welding types often refer to HIC when they mean HE or HAC! The microstructure of a weld does not lend itself to the H2S corrosion type HIC (stepwise cracking).

Steve Jones
Materials & Corrosion Engineer

http://www.linkedin.com/pub/8/83b/b04