Expansion Joint

By using Tubular Exchanger Manufacturer's Association (TEMA) standards along with ASME Section VIII, one can design a heat exchanger that will avoid over-stressing the components and tube-to-tubesheet connections. Yes, it involves the linear thermal expansion coefficient. If you can't do it, hire someone who can.

One hopes that you are not an installer and are only curious or are about to purchase such a system.

Contact the installation company who will erect the duct work and ask them to design the system for you.

That way, you will not be responsible if the duct work fails in service.

You assumed it was a shell and tube HEX.

Regardless, it depends on what is inside, the temperature variation, the shape, the route and the length of the pipes that are attached to whatever type of HEX is used. And the type of of HEX as well.

Exactly. There are many types of HEX. And OP said "in" the HEX. Does he mean inside it somewhere, or the external connections? Probably the latter, but good to know.

Sorry for the communication problems.

And thank you very much for the direction you showed me.

I am specifically looking for the conditions at which an expansion bellow is mandatory in the shell and tube heat exchanger design. It can be calculations or some postulates, I dont know. I need some guidance.

please consider that,the tube side is hotter than the shell side.

Hope I conveyed my requirement..

thanks in advance..

At last....our long process of questions and partial answers can begin !

Yes, for the junior lawyer in our group....I DID understand that the OP did not specify the HX type.

HOWEVER, THE MAJORITY OF EXPANSION JOINT DESIGN PROBLEMS RELATE TO SHELL AND TUBE DESIGNS. ALSO, ASIDE FROM EVALUATING TUBE VIBRATION, THE DESIGN OF SHELL EXPANSION JOINTS IS THE ONLY COMPLEX PART OF THE HX ENGINEERING.

SO IT WAS REASONABLE TO ASSUME THAT THIS IS A SHELL&TUBE HX......

I WAS ONLY TRYING TO SPEED UP THIS LONG Q&A PROCESS....

THE NEED FOR AN EJ IS DEFINED HERE:

http://www.wlv.com/products/databook/ch1_4.pdf

Again, it is a function of temperature difference between streams, materials of construction, tube length and tested tube pull-out strength.

How about a little bit more information....Babu ?

That's a great reference, but I stand by response #1.

Thank you Mr. MJcronin and others,

Sorry for the insufficient data.

I have a heat exchanger of-

shell side design temperature -20 degree celsius and MDMT od -60 degree celsius.

Tubes at its Design temperature 100 degree celsiuis and MDMT -60 degree celsius.

It is for dry Ice. I am worrying the differential contraction/ expansion.

Hope I provided all required dates.

You need to consider the worst case and it may not be at maximum (or minimum) design temperatures. I once had a heat exchanger with carbon steel shell and stainless steel tubes. The shell side design temperature was 550 degF, if I recall, and the tube side design temperature was 350 degF or so. However, the normal operating temperature difference was only about 50 Fdeg. Everything checked out at the design temperatures, but the pull-out was excessive under normal conditions, so we had to include an expansion joint. This was a retrofit and we didn't need stainless steel tubes, so we considered re-tubing it with carbon steel tubes, but then it was over-stressed at the design temperatures.

Thank you Sir for your valuable information. So there might be a thumb rule to decide the requirement of Expansion bellow based on the temperature difference right?

I don't know a rule of thumb to apply. However, you should be able to infer which conditions would give the largest difference in expansion between the tubes and shell. But, even that might not be the worst case, since the allowable stress may be changing, i.e. if the allowable stress is lower at a point of less differential expansion, that could be the worst case (probably not very likely, but possible).