LDS vs The Burst Disk

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which is the problem because it sounds like according to Piranha, it doesn't use either the common 3/8 size or less common 1/2 inch. it might even be 7/16 inch and the same size as a hp port.
 
Most new valves you buy now use 3/8” burst disk plugs now. So it should be very straight forward.
OP says Pirhana has said it is NOT a standard size.

Fortunately, when I left the LDS last night they hadn't removed it - I hope that's still true, as Piranha says that it's not a standard size and isn't easily replaced.
 
OP says Pirhana has said it is NOT a standard size.
Fair enough. My bad for not reading all the posts.

But OP also did not buy a regular valve.
 
post a picture if you find one, i have only ever seen either burst pressure or both service and burst pressure marked.
Here you go. This is a Sherwood burst disk, purchased from Sherwood, p/n SHV-48 3000.
Marked only for service pressure, not for burst pressure.

upload_2019-1-12_11-30-38.png


Yeah, seems like a clear opportunity for standards and consistency of labelling.
 
First, let me correct myself - p/n is actually SV-48 3000.

I have stock bought in July 2017 and December 2018. 3rd line of marking (perhaps a batch or lot #) is different, the top 2 lines are identical.
 
The one-piece valve/regulator assemblies are unusual products, and there are widely varying attitudes about the importance of having the burst disc match the cylinder pressure or indeed of having burst discs at all. I believe they are important in the USA because unlike the situation in Europe most fill stations in the USA are capable of over-pressurizing cylinders in the event the operator makes a mistake.

We are also capable of overfilling here in Europe, ant that to a higher pressure.

The compressor i usualy fill my tanks with is an 300+ bar compressor, we use it to fill tanks from 200 bar to 300 bar, and the 300 bar tanks we usualy fill to 320-330 warm.

So the only thing that stops overfilling to 330 bar in my 200 bar tank is the operatror.
 
The compressor i usualy fill my tanks with is an 300+ bar compressor, we use it to fill tanks from 200 bar to 300 bar, and the 300 bar tanks we usualy fill to 320-330 warm.
I don't just fill warm to 320-330, I also top up from 280 to 300-310 after the tank has cooled off. Compressibility is annoying.

So the only thing that stops overfilling to 330 bar in my 200 bar tank is the operatror.
And of course the protruding center section and missing threads on the whip valve which is designed to prevent a 300 bar fill whip from mating to a 200/232 bar tank valve.

Which is why our club has two adapters - with safety valves of course - so those of us using 200 or 232 bar can fill from the compressor (which has two 300 bar whips and none which are rated lower). So unless a sufficiently talented fool operates the compressor, and makes a pretty serious effort to screw up, the system is rather fool-proof. It's of course possible to overfill a 200 bar tank to some 240 bar, but that's still well within hydro test pressure.

If your fill station for some reason is using a 1st stage-like assembly instead of proper fill whips, then all bets are off, of course. Because a 300 bar rated 1st stage should be able to mate to a 200 or 232 bar tank valve.

EDIT: I posted some pictures in an earlier thread.
 
You guys are funny. Psi, feet, Fahrenheit, burst discs, ...

Why do it the easy way if you can do it the hard way :).

All the mental conversions make for brain exercise. If conversion math is too easy your brain atrophies. LOL :rofl3:
 

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