Heat Exchanger expansion joint in the correct location? 1

[gte682n]

Hello, I am trying to understand if the expansion joint for a new heat exchanger is being installed in the right location. I've attached a picture showing two supports that will be connected to the green structure above by hanger rods. The expansion joint on the shell of the exchanger is between the support and the nozzle on the column. As the equipment gets hot, would the expansion joint interfere with the support rods as shown in the picture? I am worried about the shell elongating and the support rods working in compression against the metal growth as equipment gets hot. I am not sure I am thinking this through correctly.

Thank you

 

[SnTMan]

gte682n, can only tell so much from your picture, but, I don't particularly like the EJ being between the lug supports and the apparently large channel nozzle flanged to the column. I'd guess not much flexibility between the two, depending on the support rod arrangement. I'd prefer it near the lower shell nozzle. Of course the expansion / contraction of the EJ needs to be accommodated in connecting piping as well.

Regards,

Mike

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

 

[EdStainless]

Why is there an expansion joint? Is this not a u-tube bundle in the HX?
As far as the shell goes, yes this is the correct place. But you have numerous connections on both sides of the EJ which could pose difficulties.

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P.E. Metallurgy, Plymouth Tube

 

[MJCronin]

Could we see a detailed drawing of the HX ?

What is the maximum operating temperature for the shellside ?

Are the tubes stainless and the shell carbon steel ?

As a possibility, have spring hangers been considered for support of the HX ? ...

This might help the problem go away ..

MJCronin
Sr. Process Engineer

 

[gte682n]

This is a fixed tube sheet, single pass tubes.

Max operating temp is 660 F. AL6XN tubes, 316L shell.

I have attached a drawing of the exchanger and a detail of the supports. I hope this helps.

Thank you for your attention thus far.

 

[gte682n]

Here is the drawing of the exchanger. I was unable attach 2 files to the same post.

 

[SnTMan]

Standing by my previous post...

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

 

[MJCronin]

EdStainless, this is a TEMA AEL ..... not a U-tube design.

Based on my understanding of the need for a shell expansion joint, it can be located anywhere along the shell.

IMHO, I would consider spring hangers on the rod supports to allow the HX to expand slightly downward.

MJCronin
Sr. Process Engineer

 

[mk3223]

Per your 3D model and design drawings, it has about 5-1/2" spacing between the vessel OD and the hanger rod. IMO, the hangers looks fine for supporting the vertical thermal expansion load. The thermal insulation may be applied on the shell if the temperature is an issue to the hangers.
It's supposed that the design of the lateral loads of the heat exchanger was reviewed and taken care of.

 

[KevinNZ]

As others pointed out the EJ joint is for the expansion between the shell and the tubes. It does not help with the expansion between the fixed supports and the attachment to the larger vessel.

 

[gte682n]

Hello, I received the following response from the designer:

"The COMPRESS model indicated excessive stress in the tube sheet due to the unsupported load below the expansion joint. Most of the dead weight would be suspended from the expansion joint if below the supports. When the support lugs were moved below the expansion joint the stress was removed."

They further stated that spring can hangers will be installed connected to the rods to allow for downward movement.

Thank you again for all your input.