Double disced burst disks?

[stairman]

I had a single steel 98 with h valve double disced,so I could pump it up.Unfortunatly the bolt that holds the discs in place has a 3000 stamped on it.So the guy at the dive shop that I visited on my salty excursion wouldnt put over 3000 in it.I have 5250s in my doubles,but didnt realize that since it said 3000 on the single,thats all I was getting.Hey where is everybody TDS?

[CaptainSpeleo]

If the burst disk bolt is stamped "3,000 PSI", I can understand the fill operator not wanting to fill your steel 98 over its rated pressure. Why don't you have it replaced with a bolt with a higher PSI rating?

Did I read the last part of your post correctly? Your doubles are filled to 5,250 PSI?

[stairman]

No,I go 3600 psi in doubles max.The discs are 5250s.

[nic160]

Did I read the last part of your post correctly? Your doubles are filled to 5,250 PSI?

That's what I thought he was saying !!! I re-read it now I get it !

[bernieflyer]

I didn't realize discks also had ratings. If he's got a disk rated in there for 5250 does he really need to put 2??? And are 2 at 3000 just as efficient????

[CaptainSpeleo]

Half of my tanks don't even have a pressure rating stamped in the bolt head. When I get the burst disk replaced after a hydro is done, I usually have a 3,500 - 5,000 PSI pressure rated burst disk installed to replace the old one.

[MikeH]

I didn't realize discks also had ratings. If he's got a disk rated in there for 5250 does he really need to put 2??? And are 2 at 3000 just as efficient????

Doubling up ANY burst disc is basically the same as just putting a solid plug in the hole. Putting two 3000PSI(which will blow at 4200PSI I believe) will NOT increase the blow pressure to 8200PSI....it will, at least, quadruple the burst pressure. I don't remember where I found this info, but it was backed up with the engineering data.

Mike

[aw]

Doubling up ANY burst disc is basically the same as just putting a solid plug in the hole.

Sounds like a damn good idea to me. CE or EE needs to start selling a plug.

[CaptainSpeleo]

There are solid plugs and steel burst disks available in certain dive shops, but you're not going to get these dive shops to openly advertise their availability because of the liability issues involved if someone fills a tank to 5,000 PSI and it ruptures.

[bernieflyer]

Doubling up ANY burst disc is basically the same as just putting a solid plug in the hole. Putting two 3000PSI(which will blow at 4200PSI I believe) will NOT increase the blow pressure to 8200PSI....it will, at least, quadruple the burst pressure. I don't remember where I found this info, but it was backed up with the engineering data.

You're reminding me of this girl who wanted to look cool in cave country Fla by getting a good fill to 3600psi. She got the fill on a cold late January evening (temp in the 30s) and the next day the temp went over the 80s. She had 4400psi when she put on her regs: everybody ran away......real cool....still don't know what she had for burst disks.....