2 replies to this topic

[jainesh shah]

hii

 

I have to design a exchanger with gas on shell side and water on tubeside

Shell side Design pressure is lower than the tube side design pressure

 

In such case how much should be the shell design pressure and what would be the case in tube rupture.

[fallah]

Hi,

 

General question will lead to general answer...

 

If corrected hydro test pressure of the shell side is equal to or higher than the design pressure of the tube side, no need to protect the shell side against overpressure due to the tube rupture case; otherwise you have to protect the shell side with a pressure relieving device...

Edited by fallah, 27 February 2015 - 02:55 AM.

[ahmadikh]

 Jainesh,

 

Follow Fallah's input which is generally called "10/13" rule and it used to be "2/3". However, there might be some more strict local regulations that may not be accepting "10/13" rule as an overpressure protection by system design (OPPSD), which force you to protect your lower side with a safety device although meeting the criterion Fallah explained. This is the actual case where I am working, so you would better check your local regulations.

If that is the case, you may not need to size the safety device for the catastrophic rupture of a tube, but size it for a 6-10 mm leak.

 

Hope this helps..