hello
if we use a simple model of expansion joint with internal guide sleeve, the value of effectif diameter can be itroduced exactly from effective area on expansion catalog or it possible to minimize this value according to internal guide sleeve presence
thank you for advance

Sir – The internal sleeve on most expansion joints is not intended to be a guide. It is a light weight shield to prevent flow induced vibration of the bellows elements. As a result, in modeling an EJ it can and should be ignored. The effective ID input of CAESAR II is actually a misnomer and should be effective diameter. Essentially it is the average between the bellows OD and ID and is used to calculate the longitudinal pressure thrust. The published values should NOT be changed. I hope the above helps.
Dan Edgar

thank you for your reply but if we use expansion joint to reduce reaction on pumps suction nozzle with exact effectif diameter, these reactions are highest as ollowable value. what is the ideal solution?
I think to use expansion joint with guide, can i introduce 0mm on effectif diameter with this model? i think that the pressure thrust effect will be supported by guidance rods
Best regards

Dear Sir – As I mentioned above, the CAESAR II Effective Diameter input has nothing to do with the internal liner. I’ve downloaded an engineering bulletin on pressure thrust that you should read. If you need a guide, then you should add them external to the expansion joint.

Mr Dan,
my second question is it's possible to make ID=0mm if we use a guided expansion joint with external rods? 2 rods for example

Nasreddine - No!!! Read the information I sent you and my comments above. The effective ID has nothing to do with guiding.

Mr. Dan,

I think NASRESSINE is trying to say that if he uses a tied expansion joint, can he input ID=0.