Metal Expansion Joint

[marchieV]

Hello.

It is my first time to design an expansion joint and I need some advice or tips regarding the design of expansion joint.

Actually, I need the parameters for Bellow Stiffness (for CAESAR II Input) and according to my research the vendor will provide those stiffness.
I was wondering on how the vendor will come out on such values for stiffness if the system in the CAESAR II did not yet run?
Do they have a pre-qualified selection/table? (The same like in the case of spring selection that the vendor will usually provide the table for selecting the spring based on the generated CAESAR II load of the pipe.)

In short, what data does the vendor needs to know upon requesting for the design of expansion joint?

Please help me to understand the process of designing an expansion for I have no experience on it.

Thank you and hope for your support.

Sincerely,

marchie

 

[europipe]

1) The lenght of the bellow, the rating and size of the flanges, and the movements.
2) Yes, you need a calculation of teh movements.
3) The vendor will provide you all the info.
4) ?

 

[DSB123]

pennpiper,
you say "If those bars are welded to both EJ flanges, there will be no movement between the two ends. Therefore the joint is worthless." That is pure BS. The expansion of the length of pipe that would have been there if it were hard piped is accommodated by the EJ. So there would be no relative movement of the ends but there would be movement withint he convolutions of the bellows. The tie-bars are there to prevent the pressure thrust coming into the equation.

 

[Ehzin]

DSB,

I agree that it would remove a large portion of the thermal growth for THAT section while not introducing an extreme pressure thrust due to the bars. However, I think removing that growth could be minimal. I don't see it in the earlier pictures or previous comments but removing the growth from ~1-2 feet of pipe won't do much if you still have 10+ feet of pipe in the same direction.

Thanks,
Ehzin

 

[DSB123]

Ehzin,
Did I say it would be the total solution - no. I was just saying what the bellows would be doing and laterly correcting Pennpipers mis-conception that the joint would be worthless. It may be that during the original installation the Tie bars were never removed as they should have been or perhaps someone thought about the pressure thrust "late in the day" and concluded that the best way forward was to install the tie-bars and consider the section as being rigid. Who knows until the system is reviewed/analysed. All comments are pure speculation!!!!