LDS vs The Burst Disk

[JackD342]

post a picture if you find one, i have only ever seen either burst pressure or both service and burst pressure marked.

Will check tomorrow. Even if I was right, they might actually have both marked. I just have a strong mental image of a 3000 stamped on a disk, but in the absence of an eidetic memory I can't say for sure what else was stamped.

I got curious, and it looks like Piranha is at least intending to ship valves with the correct burst disks. Could have been a mis-pick when filling the order, or perhaps the OP accidentally selected the wrong option when ordering. I do wonder about that 3180 listed though. Closest Thermo lists is a 3130 with a 4694 disk that would align with an Exemption permit spec. Same Service Pressure for 3AL/3AA would be 5250. I have no clue what cylinder would have either a 3130 or a 3180 SP.

 

[runsongas]

3180 psi for those faber mid pressure 3aa tanks. 3180+10%= 3498 psi

 

[runsongas]

Will check tomorrow. Even if I was right, they might actually have both marked. I just have a strong mental image of a 3000 stamped on a disk, but in the absence of an eidetic memory I can't say for sure what else was stamped.

I got curious, and it looks like Piranha is at least intending to ship valves with the correct burst disks. Could have been a mis-pick when filling the order, or perhaps the OP accidentally selected the wrong option when ordering. I do wonder about that 3180 listed though. Closest Thermo lists is a 3130 with a disk that would align with an Exemption permit 4694 spec. Same Service Pressure for 3AL/3AA would be 5250. I have no clue what cylinder would have either a 3130 or a 3180 SP.

I think the valve in question is the piranha pro valve not the blue steel. blue steel is a standard size afaik.

Piranha Right Side Pro Valve

although the sherwood/genesis 1/2 inch burst discs don't seem to be that rare. trident sells them iirc.

 

[viperwsu]

Wrong valve. This is the crazy thing in question

 

[runsongas]

i would exchange it for a regular valve and simple first stage

 

[JackD342]

So having seen that, I am now more open to the possibility there just might be an issue with the sizing (NOT the rating) of a replacement burst disk.

 

[rjack321]

I got curious, and it looks like Piranha is at least intending to ship valves with the correct burst disks. Could have been a mis-pick when filling the order, or perhaps the OP accidentally selected the wrong option when ordering. I do wonder about that 3180 listed though. Closest Thermo lists is a 3130 with a 4694 disk that would align with an Exemption permit spec. Same Service Pressure for 3AL/3AA would be 5250. I have no clue what cylinder would have either a 3130 or a 3180 SP.
View attachment 498620

Faber and Heiser both made some 3180/90+ rated 3AA 120cf cylinders at one time. I don't think I have seen one in the wild in a decade. For sure I have never seen a Heiser 140 which had the same SP
Scuba Cylinder Specification Chart from Huron Scuba, Ann Arbor Michigan

Edit: 3180+ 3AA faber 100s are fairly common but I don't know why anyone would put that integrated argon reg/valve on one.

 

[viperwsu]

 

[JackD342]

Pirhana needs to explain what is going on, and whether that is burst pressure or service pressure. Shame on them for selling that item without more info and context. I didn't see "buyer beware" in the listing.

 

[runsongas]

burst pressure almost certainly, but 3/2 euro hydro spec and not 5/3 US DOT. my guess is this is due to a comedy of errors involving the chinese oem. 4500 psi is fine though unless you are filling your tanks outdoors in the winter in alaska.