Potential cause of HP seat failure

[SouthernSharktoothDiver]

@lowwall Ok, so if it were aluminum oxide, I would see it in the filter? I don't have the reg currently (already dropped it off for service) but I made a point to regularly inspect my filter and never saw anything like that. Guess we'll wait and see what the tech says about it.

 

[lowwall]

@lowwall Ok, so if it were aluminum oxide, I would see it in the filter? I don't have the reg currently (already dropped it off for service) but I made a point to regularly inspect my filter and never saw anything like that. Guess we'll wait and see what the tech says about it.

Yes. That's exactly what the filter is for.

Let us know what you find out.

 

[SouthernSharktoothDiver]

@lowwall I was thinking the filter might not have been designed for such a thing, but it makes sense that it would be. I'll post an update once I get my reg back.

 

[Geo7]

@Geo7 Wait, so your concern is that there may be aluminum oxide contamination coming from inside the tank....One of my tanks has a white, powdery buildup on the inside. The fellow that did the viz (not the guy that sold me my reg, different dive shop) said it was fine, that he'd hit it with a brush and it hadn't come off, so it wouldn't be an issue, but well, could that be the root cause?

Yes, not much to add to the posts above. A white substance on the tank walls does not sound normal. And good point about the filter doing it's job, but something seems to get through and abrades our pistons in the first stage in time.

 

[runsongas]

the filter only will filter to 5 um, smaller particles can still get through

 

[Kendall Raine]

Breathing aluminum oxide particulate is potentially much worse for you (e.g. pulmonary fibrosis) than rust (iron oxide). The only way to be sure there is no contamination in the tank is to VIP it. If there is a white powder in an aluminum tank it needs to be tumbled. Sources of sea water in the tank can be several but a frequent culprit is during the filling process (more likely a boat fill)-particularly for DIN valves that have not been properly blown out prior to filling. Inspecting the filter and the HP seat may reveal a contaminant, but, as others have said, the HP seat itself may be defective.

 

[JohnN]

Hey all,
Just recently my Tusa RS 1001 regset, which I purchased back in March and has around 20 dives on it, developed a slow leak on the second stages. I took it in to the shop that sold it to me, and the owner put it on his IP gauge. Sure enough, slow internal pressure creep resulting from HP seat failure. He asked me if I'd been using it on steel tanks, which I have not, I've only used it on aluminum tanks; however, my local fill guy is known for his "hot fills" some of which are in the 3400-3500 psi territory. I specifically asked him to not overfill mine past 3300, since my reg is yoke and can't handle above 232 bar, and as far as I can tell, the pressure has never been above 3400 psi. The owner of the dive shop says it would take more like 3600-3800, and more dives than I've put on the regset, to do the sort of damage that's happened here, and he has said he believes it is a defective part and that he'll see to it that it gets fixed, but I'm concerned something I've done/allowed may have caused this, since it seems like an extremely rapid failing of a new regset. Would fills 3400 (or, assuming perhaps my gauge is slightly off or some other error is in affect, 3500) psi cause this sort of thing? If not, can you think of anything else that would?
Thanks

Just for giggles and grins. . . are one of those people who after removing the first stage from your tank, you open the tank valve and blow compressed air on the inlet of the regulator?

 

[SouthernSharktoothDiver]

@JohnN Into the regulator? No, other than once when I was being stupid. I have tried to use the air to dry the dust cap a time or to, but have found that a towel works much better for that purpose.

 

[Eric Sedletzky]

The best way to remove aluminum oxide inside a tank is to make a 3:1 solution if alumaprep33 and water. Dump in about a gallon of solution into your tank and put either an old valve on it or a plug. Swish it around and shake up the tank well, roll it around, whatever you need to do to agitate the solution. Let it soak for 10-30 minutes depending on how bad the oxide is.
Alumaprep33 will dissolve all the white oxide and stop at clean aluminum. Dump out the acid wash and rinse well with clean water. Use a cut off garden hose and hang the tank upside down to rinse. After it’s rinsed check it to see if all the oxide is gone. Repeat if necessary, you can’t overdo it.
Dry it with a hose whip from another tank and a long blow tube.
It should be bright and clean when you’re done.
I never use anything inside aluminum tanks that can chew it up like whips or even aggressive tumbling. Aluminum is soft and it can get messed up (FUBAR) really easily.
BTW, acid wash is also a great way to O2 clean aluminum tanks. They will be absolutely clean if rinsed really well. If it makes you feel better, after the garden hose rinse you can do a final with a gallon of distilled water, but to me personally that’s pushing the OCD envelope a little too far.

 

[SouthernSharktoothDiver]

@Kendall Raine So, now knowing this, I'm gonna get it tumbled before using it again. The thing that kills me is, I did get it viz'ed, and the guy at the shop said the powder wasn't coming off, he didn't know what it was, and he was just concerned it be leaching CO or something. No mention of aluminum oxide, no mention of pulmonary fibrosis, not even a suggestion of getting it tumbled. My question now is, I've breathed off that tank for about 6 hours in total. Is there anything I should do (other than getting it tumbled), like, say, see a doctor or something?