SA 105 HIC

[Sunrice]

Is the strength of SA 105 HIC different from SA 105 N?

 

[vesselfab]

Well, did you look up SA-105 HIC up in section II?

Did you find it? Didn't think so.

HIC is a generic term used for the treatment of steel during it's manufacturing process to prevent Hydrogen Induced Cracking.

I wasn't aware of any forging companies that were doing this process.

 

[Sunrice]

Thanks for reply, Vesselfab.

Yes, HIC requires chemstry control for material. Does SA105 HIC still need to be normalized? Since the Carbon content is reduced or controlled to 0.23%, is its strength the same as SA105N?

 

[SJones]

It still has to meet SA 105 minimum yield strength requirements, otherwise it won't be SA 105!!! If you are going for HIC, then ISO 15156-2 would require normalising, at least, for a forging (unless somebody wants to apply 'hot rolled' as a heat treatment term for a forging).

Steve Jones
Materials & Corrosion Engineer

http://www.oilandgaspeople.com/cv/11499664

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

 

[vesselfab]

The forging will be marked SA-105N and will meet all the chemical and physical requirements of SA-105.

If you are indeed getting HIC certified material, you should also spec out the NACE testing requirements on your order.

 

[bam8888]

You are not going to readily find a SA-105-N HIC forging. What we normally use for vessels with HIC requirements is to use SA-350-LF2 Cls. 1 forgings instead. This is a low temp qualified forging with near identical chemistry to SA-105-N, but the chemistry control and testing is more suited for HIC service. For pipe, I suggest SA-333 Grd. 6 Smls.

 

[gr2vessels]

The chemistry is the important factor, but also important is the manufacturing method and the final heat treatment of material. I would suggest you to read carefully the whole NACE MR0175 and NACE MR0103, so you'll have a documented opinion.
In addition to your topic, take note of the NACE MR0175, Clause 8 (Evaluation of carbon and low alloy steels for their resistance to HIC/SWC), this will help you understand the selection and testing requirements for the forging materials to prevent the HIC.
Cheers,
gr2vessels