Designing Rectangular Tube Sheets

Presently, I'm dealing with a rectangular pressure vessels. I need to design a Tube-sheet for it. Appendix UHX of ASME talks about only circular tube-sheets.

Existing rectangular Vessels I take it, are these ASME 'U' stamp, your also need an "R" stamp. but before you go on......

How to design a rectangular tube-sheet? Is there any code talks about it?

There is a reason why they are circular. one being integrity efficiency, On both Shell and gasketing. I never heard of a rectangular shell and tube heat exchanger.

Is marketing dept. behind this? _{Definition of Marketing Department; It like a flock of seagulls that come in, make alot of noise, crap all over the place and leave.}

Yes.. There are many industries Like, Hitachi, Thermax, etc are manufacturing parallelogram heat exchangers.

May be there is their special requirement of these.

Presently, My job is to deal with rectangular vessels?

Pramod

Are these for air or liquid?

Liquid-->> Lithium Bromide Solution.

Lets start over, 1st Size requirements

GPM (LPM) on but sides.

Pressure Requirements?

Product Temperature inlet

Coolant Inlet?

Construction Type? U-tube, Parallel Counter Flow????

Are the rectangular tanks existing and you mean to modify them?

Whats the Material?

Do these vessles have to be certified (ASME) ?

The resident expert here (or anywhere else as far as I'm concerned) on CR4 is Abdel Halim Galala. you'll probally be hearing from him.

p911

Thanks Phoneix911

Internal Pressure = 3.5 bar

Internal Temperature = 200 deg.C

Fluid -->> Lithium Bromide solution (Both side- Hot/Cold)

Counter flow Type

Tubes = U tube

Material -->> Plate - SA 516 Gr 70, Tube--> SA -213 Gr TP316L, Pipes-->> SA - 106

The vessels has to be CE (European Conformity) Certified. Presently It's not certified by any certified unit or body.

The vessel is in rectangular shape only, I need to prove with reference to ASME.

With all above .. How to start or move towards design of a tube-sheet?

Thanks

Pramod

Choose the wetted materials carefully!

If the shell pressure is low, rectangular exchangers are quite feasible. There are chillers made for the seafood industry with seawater in the shell, which is really a box, and refrigerant in the tubes. They have an advantage of avoiding damage in case of freezing. Usually the tube lattice is rectangular, but it could just as well be staggered (triangular).

There are 6 sides to a rectangular pressure vessel. 4 sides are taken care of by Appendix 13. The other two are opposite each other and need to be taken care of as a flat plate (UG-34) or as described below.

If you have a straight-tube heat exchanger with tubes evenly distributed between these last two opposite sides, you could consider these sides as a braced and stayed surface (UG-47) with tubes as the stays. For the shell (box) pressure, the tubes would be in tension. For the tube pressure, the tubes would be in compression, so some buckling consideration would be required.

If you cannot count on the tubes as support for these last two opposite sides (U-tubes or an expansion joint), calculate an efficiency based on reduced section properties for perforated plates per UHX-11. That section is applicable to perforated plates no matter the geometry or edge condition (the stress analysis for round perforated plates is done in UHX-12,13 & 14). In UHX-11, you will calculate μ*, which can be used in the place of 'E' in the UG-34 flat plate equation. (See UHX-12.5.8 for an example of how μ* is used.)

Thanks Lawrence!

I appreciate your effort towards it.

Pramod

You're welcome.

Of course the final arbiter is your AI. I'd recommend doing a calculation or a calculation plan and then verifying that he will accept it.

Lawrence