Dear all,
I would like to use expansion joint for a jacket piping.Is there any especial consideration in modeling and basecally is there any technical consideration for using expansion join in jacket piping system.

Best regards.

for me , no special expect geometrical consideration

Are you talking about an expansion joint in the spool to handle a differential between the core and jacket....or are you talking about a joint to handle general expansion of the whole piping system (such that you would need an expansion joint with a "core" and "jacket" section?

Dear Edward,

I am talking about both of them.I think the first one shall be provided by vendor.I also want to know about expansion joint for the whole piping system.

Best regards

To get your design and spring rates correct I recommend you talk to your compensator supplier.

Be carefull with your idea "leave it to the vendor". This way you do not know what you get.

This sounds a bit of a nightmare to me. AN EJ in the jacket and the core ??

I guess you are dealing with a highly viscous or solidifying fluid in the core. What will happen if the core cools, solidifies and sticks in the EJ convolutions. Then you up the heating in the jacket. The jacket will expand and the internal bellows may tear. What about initial testing / inspection of welds and convolutions ? And the need for regular inspection of the internal EJ ?

There are jacket heated, flanged flexible hoses on the market, I've seen them used in sulphur service. Worth a thought ?

Dealing with the first problem - differential expansion between core/jacket piping - can be done with a bellows in the jacket, though I've not personally done it before myself. We usually prefer to limit the lengths of the straight runs to control the differential growth to an acceptable level.

As for the second issue - putting system expansion joints that would have to have core bellows and jacket bellows - I agree with MoverZ. I would take a much harder look at adding expansion loops first.

Of course, there are no absolutes in engineering. It does depend on WHY the jacket is in place. It seems most often the case that a highly controlled heat jacket is required to keep the core medium from freezing and plugging the line. But, I've also worked jacketed systems where the jacket was a heating oil intended to control the core fluid in a tight temperature range. THis was not for freezing, but because the core material would goes through some kind of chemical breakdown if it fell outside a tight temperature range. In such a case, it MAY be possible to use a core/jacket bellows. But, I'd want that core bellows to be a two ply testable as you are going to most certainly want to avoid contamination of the core product due to a failure of the inner bellow.

Dear All,
Which one do you think work best in case of jacketed sulphur line:
EXJ or Flexible hose?
I beleive a flexible hose can handle it better as there is no convolutions inside it.

My system consists of a header and 5 branches. I think of 2 possibilities as follows:
1- Using EXJ on stright header to reduce longitudinal expansion so that I won't need much flexibility on branches.

2- Uning flexible joints on branches to handle the stright header expansion.

Please advise me if you have any points regarding this and also let me know your ideas about jacketing a flexible joint?
By the way how do you model a flesible hose in CAESARII?

Dear Micvanzil

Flexible hose also have convolution.
Flexible hose can be two type

1) Non-braided flexible - Do not take care of pressure thrust
2) Braided flexible hose - can absorbed pressure thrust.

Process industry mostly use braided flexible hose.

We do not model flexible hose in Caesar, end of the flexible hose is considered as free point for stress analysis. Search forum , you will get number of topic on the same.

Bellow/hose if required in your system, I think using it at header would be better choice.

Check if system is fully jacket or partial jacketed , means valves, & special items are only insulated not jacket?

Best choice it flexible item is avoided.

Regards

Habib

habibur21@gmail.com

how to simulate the a core/jacket expansion jiont in the CAESAR II?could you give me a example? thanks lot

regards

zzw

Dear MoverZ,
Would you please send me a vendor link for this product. I searche dthe net but founf nothing.
BEst

Try to this company:
http://www.artifex.org.uk/