Hi all,

Someone knows how can I model a expansion joint self-compensated as shown in picture following attached?

Forget stiffness of bellows. What matter is just how to model. Others values as length, stiffness, diameter, temperature, etc. will be input after modeling.

Thanks in advance,

Miyamoto

You can model a joint with no pressure thrust simply by not specifying Effective ID as part of your expansion joint input.

Dear Dave,

This joint is installed in a straight line which at one side it's a tank nozzle and another side is a pump nozzle. This joint is in charge of don't transmit any force for pump nozzle by thermal movement and pressure thrust. If I don't input Effective ID how I can know the true movements and forces in this joint?

Thanks again,

Miyamoto

Hi Miyamoto,
Thrust loads will be taken by the tie-rods and will not be transfered to the equipment. Take a note that this joint will only compensate lateral expansion. Axial thermal expansion is limited by tie rods and will be transfered onto the nozzles.

Ranka,

These kind of joint takes the thrust load by the tie-rods AND is in charge of absorb axial thermal displacement by the external bellows. This joint is very usefull for straight pipeline which one side have a pump nozzle or another sensible equipment.

If I am wrong and someone can explain me more about this kind of joint, please do it.

Regards,

Miyamoto

Miyamoto,

You are correct, RS is wrong. The joint as shown is designed specifically for axail movement with minimal axial load other than spring rate of the convolutions. This joint will accommodate practically no lateral movement, no bending displacement and of course, no torsion.

MoverZ,

Thanks for your explanation.

I modeled this joint. Someone can verify if is it correct?

I linked node 1500 to 4500 and 3000 to 6000. These links works as tie-rods.

See attached file.

Thanks in advance,

Miyamoto