I have a reverse buckling RD which indicates that the convex shape should be on the process side, what will the consequences be if it is installed with the concave shape facing the process side.

AFD

You really need to ask the manufacturer of this rupture disk this question. In general, you can expect a premature rupture. How premature only the manufacturer MAY be able to tell you.

But the real question is why? Why would anyone want to install a pressure relief device incorrectly in the first place? You are asking for nothing but trouble!!

I hope your inquiry is only an academic excercise.

The insertion of a RD is done by mech technicians and we observed that he had indeed inserted it the other way.( despite the marking)I do not know the make of the RD. It burst after a few days in service. I cannot conclude that it failed ONLY to this act as the process also has a pressure swing and temperture cycling.

Thanks phil
Afd

Pressure fluctuations will have a tendency to weaken the rupture disk over time. Also, temperature swings may very well enhance premature bursting but if designed correctly there should not be premature bursting after only a few days of operation. One of the problems for sure is the incorrect installation. If these other factors are adding to the problem as well, then I suggest you either take another look at how the rupture disks were specified or switch to PSV's. But remember, PSV's don't like severe cycling as well. If you haven't already, I invite you to read my series on rupture disks, found on this website.

The manufacturer's name and contact information must be on the RD tag. Just go out to the field and look at it. It isn't any simplier than this. Note that if the RD does not have a tag and this is an ASME coded vessel and you are bound by ASME, then this facility is in violation of the law.

Phil,

Thank you for sharing your wealth of information. I have read all your articles on RD series and the others.

Afd

Tension type rupture discs are oriented in a system with the process media pressure against the concave side of the rupture disc, placing the disc in tension.

Reverse Acting rupture discs are oriented in a system with the process media pressure against the convex side of the disc, placing the rupture disc in compression.

Reverse installation result disc in tension (which suppose in compression) and cause disc pre-mature opening. You may need to take quick action to avoid disc rupture due pre-mature opening.

You can confirm my understanding with your supplier.



regards,

JoeWong