Torque to Heat Exchanger Flanged Joint

[leont]

A recurrent leakage issue needs to be solved for a shell & tube heat exchanger at shell to tube-sheet to channel flanged joint, and partially exposed to cycle service. One of the options to solve the problem could be bellville springs washer. This is type sandwich flanged joint (shell-tubesheet-channel) with 3/4" studs
Other than normal considerations for a normal flanged joint, I need some heads up from this forum in order to know what additional considerations I have o take into account to guarantee the seal of the joint for heat exchangers

Thank you in advance

 

[SnTMan]

Well, no guarantees, but see ASME PCC-1.

Regards,

Mike

 

[racookpe1978]

Show us a sketch or dwg of the problem - to scale. I can't picture from your description how a bellville washer would help.

And, if it it would help, I'd like to see how it works so I can learn what was the problem. 8<)

 

[XL83NL]

I just read a paper by W. Brown. If you dont know him, make sure who he is. Get familiar with his work and his papers, if youre into flanges joints.
The paper, as far as I remember, clearly stated bellevilles are commonly used as a solution, but definitely are NOT.
If you want i can see what the papers nummer is. He sent it to me through linkedin.
I suggest you familiare yourself with pcc-1 as a starter, and get the real root cuase of the problem and solve that.

 

[SnTMan]

Belleville washers (springs) are often used to mitigate loss of bolt load during operation. That is pretty much the limit of their usefulness. They won't fix a poor bolted joint condition or design

Regards,

Mike

 

[leont]

Thank you XL83NL,
I really appreciate whether you make possible I can read this papaer. I have been chasing this paper from W. Brown with no success at all.
The split side of this is I have been told about implementation of bellville washer in heat exchanger flanged joints with tremendous success,which make sense as you keep bolt pre-loaded with the torque value calculated in order to guarantee the sealing of the joint, no matter cycle service and gasket relaxation shows up. I am trying to get technical lights related with additional considerations we need to handle when the work has to be done on flanged joints like shell to tubesheet to channel.

I will go deeper on ASME PCC-1 and I will get back with the forum to provide more details.
Again, I really appreciate whether you help me to get that paper

Appreciated

 

[XL83NL]

I maybe shouldve said that bellevilles might be a solution, but their use isnt necessarily meant for that intent. Your solution should be finding the root cause, as bellevilles work, for this purpose, as band aids that eventually will bleed (again).

 

[GenB]

Serious analysis is needed here. I think the tubesheet thickness is the problem, but it can also be the flanges thickness either side or both.

 

[MJCronin]

Has the flanged face become warped after many thermal cycles ?

Was this checked at last bolt-up ?

Can you provide pictures and describe the service ?

MJCronin
Sr. Process Engineer