SA182 material use for nuclear valves (ASME Sect. III)

[galanmiha]

Dear all,

I am asking for your support in trying to understand which is the right approach in using the material specification SA182 for construction of nuclear valves.

- According to SA 182: "4.4 The material shall be forged as close as practicable to the specified shape and size."
- According to ASME Sect. III, ND-2124 "Material Size Ranges and Tolerances":
(a) Material outside the limits of size or thickness given in any specification in Section II may be used if the material is in compliance with the other requirements
of the specification and no size limitation is given in this Subsection. In those specifications in which chemical composition or mechanical properties are indicated to
vary with size or thickness, any material outside the specification range shall be required to conform to the composition and mechanical properties shown for the nearest
specified range [NCA-3856].
- according to ASME Sect. III, ND-4211 "Cutting":
Materials may be cut to shape and size by mechanical means such as machining, shearing, chipping, or grinding, or by thermal cutting.

My question is:
Am I allowed to use Forged bars (SA182) long of 8000 mm (eg), cut it in 4 pieces and make the plugs? Or do I have to order other forged bars at dimensions "as close as possible to the plug size"?

Thnk you!

 

[EnergyMix]

I finally had an opportunity to look up the Code. I don't see a problem with your cutting up the long bar of SA182 to make the plugs or valves or whatever you are planning. You will need to have enough left over for test coupons, if you are forging the material. (See ND 2223.)

Also remember you need to meet all parts of the Section III Code, you can't "cherry-pick." I'm only saying this because you quoted from a section on forging and a section on machining. I can't judge one way or the other.

 

[galanmiha]

Thank you for your answer.
I referenced the articles in Section II and Section III that were reflecting our situation. Ofcourse, we have to comply with all other applicable requirements of the Section III.
We had a problem related to the size at which the materials were forged. We were told that we should have forged the material used for plugs at dimensions "as close as possible to the plug size" and we shouldn't have used the 8000 mm long bars.
This situation may force us to scrap all the plugs and order new ones.

After reading very carefully the specification SA182 and the Section III of the Code, my opinion was that we haven't done anything wrong. But, to be sure that my interpretation is not wrong, I needed also others (expert)opinion.

Thank you!