Plate & Frame ASME Stamp

[steamdog]

I supplied a P&F Heat Exchanger that had to be ASME stamped. This exchanger is rated at 350 psig. The unit was supplied with an 'M' stamp (miniature).
The total internal volume is about 5 cubic feet. The size limit for an 'M' stamp is 3 cubic feet at 350 psig. The manufacturer stated that the P&F is actually considered two vessels, and each vessel would be 2.5 cubic feet in this heat exchanger and he is allowed, then, to use the 'M' stamp.

The end user has questioned this, and any input would be appreciates.

 

[RJVanS57]

I work for a S&T manufacturer. This sounds very familiar to the practice used here, where (for example) the shellside (refrigerant) of a flooded evap is declared as code-compliant, and the tubeside (brine) is declared as none-code. The tube volume is subtracted from the gross shell volume, giving a net shell volume. This would be the actual volume of potentially hazardous fluid.

I've never worked with P&F, but I imagine you would apply the same principle here.

It would be interesting to see other responses to your post.

 

[rmw]

I work for a S&T manufacturer and the shell and the tube bundle are considered as 2 vessels and each vessel has its own nameplate and stamp.

On this basis, if that has any merit, it would logically seem that your Mfg'r should provide 2 stamps and nameplates.

But that doesn't make it right just because we do it.

rmw

 

[doct9960]

steamdog,

Where would this exchanger be installed? Some jurisdictions do not recognize or accept the UM stamp.

 

[jte]

Good point about jurisdictional acceptance.

Shell side and tube side count separately.

In an assembly of vessels, the limitations in (1) through (3) above apply to each vessel and not to the assembly as a whole.

Question: Do the volume and pressure limitations listed in U-1(j) apply to each chamber of multichambered vessels that are rated and operated independently?

Reply: Yes.

Question (1): In determining the volume limit for the shell side of a shell-and-tube heat exchanger under the requirements of U-10) in Section VIII, Division 1, may the volume of the tubes be deducted from the total volume when the tube side is exempted from Code requirements?

Reply (1): Yes.

Question (2): Same as Question (l), but the tube side is. not exempted from the Code?

Reply (2): Yes.

See also Interpretation VIII-1-89-203

jt

 

[steamdog]

Thanks to all. It seems the UM is valid for this heat exchanger, if accepted here in NYC.

 

[GenB]

"Question (1): In determining the volume limit for the shell side of a shell-and-tube heat exchanger under the requirements of U-10) in Section VIII, Division 1, may the volume of the tubes be deducted from the total volume when the tube side is exempted from Code requirements?

Reply (1): Yes "

I would challenge the interpretation. UM stamp 's for a single chamber vessel. I see many Mfrs deviations and get away with it.
someone in that Committee mfrs HXs, insiderrr

 

[GenB]

I should mention that this news is good for me too.
I can use the interpretation.
'sorry about the above