Plate Normalized + Pipe Normalized = 2 Normalization on same pipe?

[Stileman]

Dear Sirs,

I'm talking about a Client Specification that requires an NPS 30 pipe to be manufactured as per A672 C60 Class 32 (i.e. Normalized) and, in addition, this pipe shall be made from a plate as per ASTM A516 GR60 Normalized!!

Practically my Client asks for a double normalization heat treatment, on plate first and then on pipe after welding. I find this choice to be quite odd, do you agree? What's your experience about? Did it ever happened to apply a double normalisation heat treatment? What risks may I occur? (My first concern is that no Vendor would supply such an Item!)

For the sake of clarity, I specify that I'm in HIC service, 248HV on HAZ and 200HB on weld deposit (practically NACE MR0103 but not explicitly mentioned).

Thank you for your attention, I hope for a reply of yours.

Regards,

ES

 

[SJones]

Does the client specify HIC testing of the plate or of the final pipe?

Steve Jones
Corrosion Management Consultant

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

All answers are personal opinions only and are in no way connected with any employer.

 

[Stileman]

Hi Steve,

Client doesn't ask for any HIC testing, namely NACE TM0284. Nor they require plates specifically manufactured for HIC.

 

[SJones]

It's not unusual. The plate normalisation requirement is usually to get it to pass a HIC test as some specifiers believe that HIC testing the starting plate alone is acceptable even if it is then subsequently rolled, welded and heat treated again. It's the client's money if they wish to spend it.

Steve Jones
Corrosion Management Consultant

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

All answers are personal opinions only and are in no way connected with any employer.

 

[weldstan]

Agree with Steve. I have often seen this done. Impact toughness was improved. Filler metal selection for the long seam weld is paramount to assure its strength and toughness properties after normalizing.

 

[MagBen]

practically yes, but technically the first normalization is not necessary unless it can facilitate making the final pipe.

 

[Stileman]

OK sirs,

thank you all for your valuable answers. So it's my understanding that Yes, it may be done a double normalization heat treatment without affecting mechanical properties, i.e. Tensile/Yield Strength, below applicable pipe specification, namely ASTM A672. Good to know!
By the way, I'll keep you posted about my Client decision, because I proposed a normalization on plate + stress relieving on pipe after welding (just to be sure to meet 200HB on weld).
ES

 

[SJones]

So, you want to change the class of pipe ordered by the purchaser? Good luck with that.

Steve Jones
Corrosion Management Consultant

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

All answers are personal opinions only and are in no way connected with any employer.

 

[Stileman]

Yes Steve,

we are at bid stage, nothing was manufactured nor any operation started yet. So, no problem to change pipes from ASTM A672 GR. C60 Class 32 to Class 22. Vendors have just to update the offer, nothing more than that. Regards,

ES

 

[SJones]

Yes, but that's a simple task between you and the supplier. What about the specifier's say in the matter before you so blithely switch grades?

Steve Jones
Corrosion Management Consultant

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

All answers are personal opinions only and are in no way connected with any employer.

 

[weldstan]

Get a price for both and make our proposal to your Client. I doubt that there will be a great price differential because there are 2 heat treat cycles in both cases.

 

[Stileman]

Yes weldstan,

it's what I'm doing with Vendors. I asked for a double quotation, and on the same time I required a meeting with Client to discuss technical matter. I deem a double normalization not to be technically necessary (CVN Impact test shall be conducted at +5°C, 27J min.) so, a stress relieving may largely suffice to meet mechanical and hardness requirements.

I'll keep you posted about the end of the story. Best regards,

ES