Heat Exchanger with fixed tubesheets gasketed with shell. 2

[cak4Engg]

Hi,

Received a requirement to make a Heat Exchanger in the below-shown configuration.
Here both front end and rear end bonnet flanges and bolted to shell body flange and the tube sheet is sandwiched in between them.
I am not able to identify the configuration for this type of heat exchangers (if it is valid configuration).
As both, the ends of the tube sheet are fixed my understanding is that it should come under BEM type. but in that configuration, the tube sheet in rear-end shall be welded to the shell.

Really looking forward for a response from the community.

 

[SnTMan]

cak4Engg, it's mongrel. Given that both bonnets are bolted, you'd kind of want to call it an AEL, but having no separate, bolted covers, more like a BEM.

On second thought I suppose you could just call it a BEM.

If the tubesheets are truly fixed, and truly gasketed to the shell, to me this would be a very poor practice. If the shellside gasket were to leak there is no good way to correct it.

I'd weld the tubesheets.

Regards,

Mike


The problem with sloppy work is that the supply FAR EXCEEDS the demand

 

[marty007]

I've only ever seen this configuration once before. It is used when the tubesheets are made from materials that can't be welded to the shell material (Ti, Zirc, Ta, ...).

The better design though is to use a lined tubesheet (preferrably explosion bonded), and weld the shell to the tubesheet base material. The tubes can then be seal welded to the liner.

Cheers,
Marty

 

[Christine74]

Figure 1 in the PDF below describes this configuration, which I would consider a special type of BEM exchanger:

http://www.graham-mfg.com/usr/Product Manuals/OMI_SC_0401.pdf

"It is important not to break this seal between tubesheet and shell flange.
The tubes are expanded into each tubesheet holding them firmly in place,
and the shell seal cannot be replaced without retubing the entire condenser.
To prevent breaking the joint, it is important that all nuts be removed from
the waterbox flange side and not from the shell flange side. Do not loosen
or remove the stake studs and double nuts on the shell side"


-Christine

 

[SnTMan]

Christine74, nice link, thanks.

The problem with sloppy work is that the supply FAR EXCEEDS the demand