Thick wall A694 F60

[TerryR1]

We're looking to make some thick-wall piping components out of A694 F60 material. The final part's cross sections range from 4in to 9.5in. Top spec is API 17G.

We're considering forging & then rough machine the part to have surfaces within 1/2" of the final part. Then heat treating (Q&T) to get properties, and then final machine.

Could someone with experience with thick-wall forgings and/or A694 weigh in on this? Is this too thick to get the required properties?

Required properties:
60ksi min yield
174-235 HBW hardness
TCVN 32ftlbs @ 14F
Verified at 1/4T and 1/2T, to best of our interpretation.

I'm thinking the surfaces down 2-3 inches will be good, and pass the T/4 test. But much past that material will be weak. Theoretically this shouldn't be an issue, as I don't see the part breaking where it is thickest. But I'm not sure how to justify that with the spec's T/2 requirement. Help / shared experience much appreciated!

 

[metengr]

There are some papers on this subject;

https://www.researchgate.net/public...60_-_HEAT_TREATMENT_AND_MECHANICAL_PROPERTIES

http://mit.imt.si/Revija/izvodi/mit116/balcar.pdf

You may need to work with a mill to have a custom chemical composition to reach minimum tensile properties at 1/2 thickness.

 

[TerryR1]

Thank you. Yes I had found those; they only go to 4" thick. My finished wall is 9.5" thick, 10.5" thick at heat treat.

 

[metengr]

Your going to have to see what properties you can achieve on your own. This means doing some type of qualification, again working with a reputable steel mill.

 

[TerryR1]

Hence the question asking if someone has experience with this.