Dear all,

I am evaluating 18" expansion joint in between nozzles in head of two horizontal drums with design pressure of 6 barg.
Distance between nozzle to nozzle face is approx. 2.5 meters.
Expansion joint length is 450mm connected directly to one nozzle and the remaining length is connected by 40S pipe to other nozzle.
Expansion joint is subjected to axial compression of 37mm and lateral movement of 11mm. Equipment support will handle the pressure thrust.

Due to it's location putting guide in pipe is not possible so I added control rod in expansion joint.
I'm checking if it is sufficient. Considering the unguide 2.05m spool piece is there any possibility it will create additional bending moment to nozzle due to pressure?
Any more consideration I have to make?

Thanks in advance.

Are the vessels are on the same axis since you are quoting nozzle to nozzle face ?

Or are the vessels side by side ?

What causes the 11mm lateral movement ? Is the EXJ designed to accommodate this ?

Yes the nozzles are on same axis facing each other and same elevation.
Lateral displacement is to account for steam out condition
of one vessel while the other one is on ambient.
In normal operating condition lateral movement is
of no concern.

Correction, spool piece is almost 3 meters length.

EJ Vendor accepted both axial and lateral displacement.
EJ vendor stiffness is also acceptable for nozzle loads.
My main concern now is the unguide pipe length which may cause sideway
movement and overloading the nozzle.

What, apart from deadweight would cause a bending moment ?

There seems to be no reason to guide the pipe since there should be practically no lateral loads, at least due to process / expansion conditions. A weight support might possibly be required, if so it would be a spring.

By control rods, if you mean adding tie rods, you will merely destroy the ability of the joint to absorb axial expansion.

Assuming you have just one set of convolutions, You should check again to be sure that the length is sufficient to absorb the imposed lateral deflection.

Thanks Moverz. It's only a control rod. Axial
compression is not restricted by it.

I already proposed spring hanger but client did not see it as
necessary. Instead I only used rod hanger to support the
Weight.

For the convolutions check of lateral movement , I would manually check
refer expansion joint catalogues for some guidelines.

Many thanks again.

Er, um .... what does a control rod actually control ?

Your rod hanger must somehow deal with 11mm of (presumably) upward movement as you have described. How is that going to work ?