Confined Gasket on Internal Floating Backing Device

Perhaps you could reproduce Fig RCB 5.141?

I don't think your proposal will satisfy the requirement; a retained or confined gasket must seat in a groove that fully surrounds its i.d. and o.d.

Hi Tornado, thanks for your reply.

The floating tubesheet will have a step or groove in order to retain the gasket i.d. just like Fig RCB 5.141 style A. The only modification is the floating head flange does not has a step or groove but the gasket o.d. is retained by its outer ring instead as allowed in R-6.5. Should this construction fulfill the TEMA-R requirement then?

Thank you.

I haven't dealt with this recently enough to remember the pictures. If the gasket is backed up by the flange material (on the o.d. for pressure applications, on the i.d. for vacuum), then I think it is okay. However, your local Code may mandate a particular geometry.

Once again, a picture or sketch would help.

Regret that I have difficulty in uploading a picture here... But how can I post a .pdf file instead?

I don't think CR4's system accommodates .pdf files or other attachments. If you send me a PM (private message), I can give you an email address that does accept attachments.

Hi I have sent you the sketch on the flange joint design for the internal floating head...

The 5 mm step-in at floating head flange is very important, since a retained or confined gasket must seat in a groove that fully surrounds its ID and OD as derived by Tornado, which is very effective in positioniong of gasket in its correct location, and that surrounding is also necessary to resist and avoid the damage of gasket during operation.

In addition to that, the proposal of yl0525 shall produce a large gasket with a wider width which leads to more higher expensive product of that special type of gaskets.

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Hi Abdel, thank you for reply. So can I conclude that my proposal can be considered one of the confined joint construction which fulfill the TEMA-R Standard requirement?

Dear yl0525, we can't consider your proposal as complying with TEMA-R Standard requirements.

Notice that if you push together all the pieces shown in Post 7, the gasket is surrounded on all four of its surfaces. A "tongue-and-groove" joint also does the same (the groove in one face surrounds the i.d., o.d., and a third surface of the gasket; the tongue of the other face presses on the fourth surface of the gasket.)

In the private message drawing, it appears that the "back-up ring" could move to one side or the other, allowing the gasket to be pushed outward by internal pressure. I don't think it would work, unless some dimensions/proportions were changed.

Hi Tornado, the gap/ spacing between the head flange and the backing split ring is restricted to 6mm max. I would say that chance of the gasket guide ring to give way is relatively small. What do you think?

In the basis of your drawing, I would say that chance of the gasket guide ring to give way is relatively large. You might be surprised at what can squeeze through a 6-mm gap....

See also post 8.