Head thickness on Nameplate

[eong]

Hi all,

Our customer asks us to show shell/head thickness on their nameplate, so i wonder which head thickness shall be indicated in the nameplate, min. thickness after forming or nominal used thickness?

At first, I used min. thickness after forming to show that this is the limit thickness but i got the comment to show the used thickness.

Please advise your all opinions.

Thanks

 

[c8829]

Strange demand from customer, but anyway the solution is like
Head: 14/12 (For example) (Nominal/Minimum)
Shell:12

 

[racookpe1978]

I would add "Design Nominal Th" & "Design Minimum Th" since in future years you don't know what the actual thinnest section anywhere might be after fabrication. I was thinking the owner wants some record to compare measured corrosion and erosion against in some future outage. But that would be on the drawing anyway, so ???

 

[EdStainless]

But we all know that they don't bother to keep the drawings.
At least they can never find them when they are needed.

The only thing that I would put down is "design minimum" since that is what you are responsible for.
If they want actuals then they can measure them.

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, Plymouth Tube

 

[GenB]

When is not a requirement, you can add n the nameplate whatever the customer command in the purchase order. Just ask what they want to see. Mom or min. Its that simple.

 

[racookpe1978]

Well, my mom is pretty short, but at least I can measure her. (Nice distance for a hug certainly.) 8<)

But the design/engineering team/company can't really control the "actual, as-built minimum" thickness, and can only certify it on the nameplate if they are able to measure the whole fabricated head fairly closely under controlled conditions. And even then there are going to be +/- values involved.

Customer rules of course, but you really do specify in the "design" a minimum thickness taking into account unknown future corrosion losses, fabrication tolerances, material tolerances. So you "buy" a nominal thickness.

 

[metengr]

Nominal thickness.

 

[sharmass]

I think if you need to mark the thickness on name plate, you should put the same thickness that you certified on data reports.
Any variation will be considered as non conforming situation