Metal fittings and RO water.

Can you offer the products name/model or post an image of the fitting?

You "typical" metals used by drinking water are (there a bunch of new alloys out there and of course coatings applied to who knows what): Copper, Brass, Nickel, Stainless and steel (Galvinized Zinc). Black Iron is not used w/ drinking water. These are your typical choices, but I have seen different alloys used in certain situations typically w/ pressure.

Regardless I think it's a safe bet that the fitting that came with you $60 tank does not pass your quality standards - especially if it IS stainless or a steel-alloy. Also, if it is coating, taking a shaving is a bad idea (it will ruin any corrosion protection it had).

Also judging from you response (it is just plain steel...) I would assume Galvy atm...?

EDIT: GratZ! :D
 
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It would seem now that I have accidentally stumbled on to the answer to my question of what metal this is.

When i minimized my page, I had open a page of pipe fittings that I didn't get a chance to look at lastnight.
Upon looking closely at these 304 Stainless fittings, I noticed that the metal looks identical in appearence to the flange plate on my tank.

It is (presumably) 304 Stainless steel.

I managed to dig up this information about 304 SS on the following page
http://www.azom.com/Details.asp?ArticleID=965

Chemical Formula

Fe, <0.08% C, 17.5-20% Cr, 8-11% Ni, <2% Mn, <1% Si, <0.045% P, <0.03% S

Corrosion Resistance

Excellent in a wide range of atmospheric environments and many corrosive media. Subject to pitting and crevice corrosion in warm chloride environments, and to stress corrosion cracking above about 60°C. Considered resistant to potable water with up to about 200mg/L chlorides at ambient temperatures, reducing to about 150mg/L at 60°C.


I would have to say, based on the information on that page, that this "304 SS" is suitable for this purpose.

A few good rinses with water should suffice.

Now I need to buy a tire pressure gauge to see what the tank is pressurized to :)
 
Can you offer the products name/model or post an image of the fitting?

You "typical" metals used by drinking water are (there a bunch of new alloys out there and of course coatings applied to who knows what): Copper, Brass, Nickel, Stainless and steel (Galvinized Zinc). Black Iron is not used w/ drinking water. These are your typical choices, but I have seen different alloys used in certain situations typically w/ pressure.

Regardless I think it's a safe bet that the fitting that came with you $60 tank does not pass your quality standards - especially if it IS stainless or a steel-alloy. Also, if it is coating, taking a shaving is a bad idea (it will ruin any corrosion protection it had).

Also judging from you response (it is just plain steel...) I would assume Galvy atm...?

EDIT: GratZ! :D


I do not know of any brand name... nothing is on this tank.
Its blue, has 3 legs. I purchased it at princess auto, for those who know the store.
It is likely either overstock, or surplus from somewhere else and if it isnt, then it is Princess Auto's house brand "Power Fist"..... but they never leave off a label, so this isnt likely.
But it was more expensive previously, so dont use the budget price as a guide so much... I think it was originally like $99, which is what I usually see these things selling for.

I am unsure about the flange being 304 stainless, but it seems likely, as that seems to be a fairly cheap grade of stainless, used when making potable water systems and the like, and being the tank came from a surplus store of sorts it would be the type of product to use a chaper grade of metal suited for the application at hand.

I think i will call plasco and see if they could possibly manufacture this flange out of plastic, and if so how much.
Just because im curious.... If this is 304 SS, I think it should be OK.

unless someone else has other ideas.
 
I had an idea, and what i think i might do, is use some of the marine epoxy i puirchased for my background, to seal this metal.
this way no metal will be touching the water at all.

simple problem, simple soloution :)
 
sealing the metal seems easy to do but in reality may not work..if this is a flange.hinge etc..it is attached to the box..no?
there is chance that the seal will break when attaching the flange back in place..also if there is any moving parts..you will inevitably wear thru the seal.

I'm curious why you need this water to be so pure.
 
this is an accumulator tank..... not a box, and has no moving parts.

sealing the metal will work in this instance.

And the water is so pure.... simply because I have the means to do so. :)
 
the powder you were talking about on the rubber would be like talcum powder its used to stop the rubber breaking down when dry.
 
ok, So I got some pics of this water tank..... My GF has aptly named it "Oswald the Octopus" .... and those of you with children will probably know why..... she looked at me rather strangely when I began taking pictures of oswalds private regions and then further, his insides..... actually it sort of creeped me out for a bit there too lol.

The tank itself. 9.2 gallons is its listed size. Assuming an approx. difference of 2 gallons based on other tanks I've seen, it should hold about gallons. I know nothing about it, including its max rated pressure, However I assume its 80 PSI as the rest of our water supply is.
I was unable to verify its precharged pressure before I discharged it.
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Here is the metal flange which has been the topic of much discussion in this post :) You can see it is rather large, and secures the bladder.
I believe it is a 1" pipe thread.
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The flange removed.
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A peek inside the tank itself. Are most accumulator tanks built this way? with a large bladder inside a tank like this? Or are they lined inside the tank itself?
The metal tank itself looks a little rusty, so I may shoot some rust paint in there before I actually use it.
Also, will this bladder expand? or will it remain its current size under pressure and full of water? it seems alot smaller than the actual tank itself, and not like it will hold even 7 gallons of water.
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A look inside the bladder... a little powdery, but generally good condition, just needs a real good flushing before use.
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Lastly, the air valve, to rpessurize the tank.... nothing really more to say about this device except that its covered with a nice little cap :D
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