Is this normal for scuba tanks?

[Marie13]

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[Gone for diving]

Chinese stuff can be tough to know what's real fake or otherwise.
I personally would not have a huge problem using it..
Pumping by hand the bottle will not see any heat... I have welded pressure vessel that take 3000psi at home no problem...
Steel is way more forgiving...
With aluminum they work on ridgitiy...
If worried put it in a bucket of water and keep submerged... fill the bucket right full of water. Then fill the tank with air to rated pressure.. if no water spills it should be fine... there is no expansion of the tank... a lid on the bucket would be best.

 

[chillyinCanada]

I don't know if this is from the manufacturing process, or if it's a form of corrosion. It is a small 1L tank that I got on bang good (DCCMS DS-810 8pcs/set 1L Portable Diving Scuba Tank Divers Spare Oxygen Equipment Leisure Diving Mini Oxygen Tank). I used it in the water after pumping it up with a high-pressure bike tire-like pump. It worked fine in the water, the air was normal, and the regulator was good. It lasted 20 mins pumped to 200 bar.

I opened it up to make sure no water leaked in it and I noticed the black on the side of the tank and put a borescope in to see what it was. It's a very thin layer of, idk what. It can be scraped off and it puts little particles in the tank. My dad recommended putting airsoft bbs and some alcohol in there to wash everything it by shaking it. He said it could just be from when they made the cylinder, but I just want to make sure it's not corrosion or anything.

Does your dad dive, Noah?

 

[Noah Norman]

Good point. He can throw it away in ten years. Much better.

So as long as I take care of it and clean it after use, keep track of the inside and threads, it is approved to last 10 years? ALSO, what does PW200 PH300BAR mean? It says to fill to 200 bar, bit is 300 bar it's Saftey limit? I will still only be filling to 200 bar, I just want to know.

 

[Gone for diving]

If it helps some of you sleep at night, I got a large DOT tank that I'm going to use to fill the smaller one. Anything, in particular, I have to do with the DOT tank, I know it has to be serviced and inspected at certain time intervals, what are these time intervals, and what else do I have to do to be on the safe side with it.

Keep out of the sun with full pressure...
Don't drop them
Treat them relatively carefully... kinda like you own them.... not like a rental

 

[Noah Norman]

Does your dad dive, Noah?

Yes sir, and he says the tank is perfectly fine. I just need to clean the stuff out and it'll be great. He just got a DOT tank that we are going to use to fill this smaller one.

 

[chillyinCanada]

The scorkel and its generic variants have been the subject of much discussion and derision here. If it works for you, most of that isn't relevant.

There are two questions you should consider related to the safety of the cylinder. The first is the one you ask. There should be no visible corrosion or residue of any kind on the inside walls of the cylinder. Depending on what is there, you may be able to remove it using hot (boiling) water mixed with dish soap or household ammonia, followed by several rinses. Marbles or other objects can be used combined with rolling the cylinder. There are also commercially available bottom brushes and whips that can be used to perform mechanical cleaning.

Second, as implied upthread, there are safety standards for the manufacture and testing of high pressure cylinders as defects or damage can lead to explosion and personal injury or death. While the risk is lessened somewhat with a smaller cylinder, it is still significant. For cylinders used in the USA there should be a "DOT-3AL" stamp followed by the pressure rating in PSI, or a "UN" stamp with internationally recognized information. These would indicate that the manufacturer claims the cylinder follows the applicable safety standards, though there have been instances of fradulently placed markings on small imported tanks (notably for portable welding equipment).

The absence of such markings would indicate that the cylinder does not meet USA standards, and may be unsafe.

May be unsafe? It's definitely unsafe. Who knows what little flecks Noah may have breathed in during his explorarory try.

 

[Noah Norman]

Keep out of the sun with full pressure...
Don't drop them
Treat them relatively carefully... kinda like you own them.... not like a rental

yeah i'm gonna cut out a foam cover for the top of it so the valve doesn't get hit by anything.

 

[Noah Norman]

Chinese stuff can be tough to know what's real fake or otherwise.
I personally would not have a huge problem using it..
Pumping by hand the bottle will not see any heat... I have welded pressure vessel that take 3000psi at home no problem...
Steel is way more forgiving...
With aluminum they work on ridgitiy...
If worried put it in a bucket of water and keep submerged... fill the bucket right full of water. Then fill the tank with air to rated pressure.. if no water spills it should be fine... there is no expansion of the tank... a lid on the bucket would be best.

ohh thank you, I will try that.

 

[Noah Norman]

May be unsafe? It's definitely unsafe. Who knows what little flecks Noah may have breathed in during his explorarory try.

If it helps I feel perfectly fine, and I felt fine while and after using it. I also filled it up a little more, only to like 50 bar. Then pushed the regulator, aiming it on a wet towel until it was emptied, nothing came out.