Rupture Disc

[crthomps]

I could use some help on a safety disc I developing. I have a specified burst range that I need to meet and I am coming up high. The bore size is .295" and I am currently using .006" thick brass (70/30 CA260, 1/2 hard). The range is 2500-2775 and I am about 3150 w/o a burst. Does anyone have any material/design suggestions? I feel like I am wasting time and money by changing the hardness and thickness and hoping to get the right range the next time through.

Also, is there some reference material (books, articles, etc) out there you can suggest so I can get this done right the first time?

 

[unclesyd]

Though I haven't done much work in the Cu alloys, from experience your thickness seems high.

I don't know of any information on the design of rupture discs.

What type disc are you try to develop, is it a prebulged, flat disc, etc?

Comeback with how you are attempting to make the disc?

How are you trying to test the disc?

 

[pleckner]

Is this an ASME Coded vessel you are trying to protect?

 

[crthomps]

The disc is flat and was stamped out of a strip. We have a testing block that we use to burst test the discs. I'm wondering what would happen if I only drop the thickness down to .004", and leave the hardness at 1/2 hard.

 

[pleckner]

WOW, red flags go up!!

If this is an application for an ASME coded vessel and you are not a certified shop, then you are violating the law by trying to design your own rupture disk. If you are a certified shop, then you would know how to design the rupture disk properly so by the very nature of your question you are not a certified shop and therefore violating the law. Contact a certified manufacturer of rupture disks is my only advice and should be the only advice anyone gives you.

If this is not an application for an ASME coded vessel, you should still contact a certified manufacturer of rupture disks because by trying to do it yourself you are risking not only equipment damage at the least but someone's life at the most.

If I'm missing something here, please educate us all.

 

[Latexman]

Why would you go through this time and effort for something as readily available as a rupture disk?

Good luck,
Latexman

 

[JimCasey]

The rupture disc manufacturers routinely make special rupture discs. One might argue that they are ALL special, after looking at all the discs they burst to verify the properties of the ones they ship. Nevertheless, if you will contact your friendly neighborhood rupture disc vendor, he will be able to help you. He will want to know what the media will be, the temperature, the burst pressure, and the operating pressure. He will need to know how the disc is to be installed-in a holder or as part of a welded assembly, etc. If the operating to burst pressure ratio is 70% or less, design is relatively simple and he can offer a prebulged disc. At higher operating/burst ratios, the disc design needs to incorporate some tricks.

Continental Disc Corp, Fike, OSECO, and BS&B are names that come to mind.