Stainless Steel Water Tank Brands

[JayBee]

Any opinion on Advanced vs Diamond brand water tanks?

[lopburi3]

Worth the cost - have two Diamond 18-8 1200 liter tanks that are over 2 decades old; so they do last. But no knowledge if one is better than the other.

[overherebc]

Another option would be the fibre tanks being sold at Home-Pro. I don't know price differences, but I like the appearance of them more than the stainless.

Small technical point is to check the little pin that connects the ball lever to the inlet valve as in some cases it's very small and not rust proof with the result that when it gives way, usually at 2am when your torch batteries are flat you wake up to a new pool in the garden and a fair sized water bill.

[wayned]

Have two Diamond tanks at my houses and two fiber tanks at out buildings (pig pens). All over 10 years old with no problems. Only problem I've had is with the brass ball lever inlet valves. Replaced them with the PVC cutoff valves and have had less problems. Main problem is dirt in my local water supply not allowing the valve to close fully. PVC valves easy to disassemble to clean.

[Nowhereman60]

One thing to be look for if water is leaking from the top of your tank. My PVC ball got a small crack and it filled with water; Couldn't figure out why my tank was leaking until the expect water repairmen came and knew right away.

[luudee]

I used to have two "stainless steel" water tanks. Both roasted through after about a year. Apparently Thai

Stainless steel is not suitable for well water that is iron rich. There was a warning in Thai on them, which of

course none of my Thai installers mentioned to me.

Since than I replaced them with two plastic tanks (in my case they are both 5000L). Had the plastic ones

now for over 9 years, no problems. Mine are covered, so I don't know how they would do in UV rich sunlight.

Cheers,

rudi

[Soutpeel]

I used to have two "stainless steel" water tanks. Both roasted through after about a year. Apparently Thai

Stainless steel is not suitable for well water that is iron rich. There was a warning in Thai on them, which of

course none of my Thai installers mentioned to me.

Since than I replaced them with two plastic tanks (in my case they are both 5000L). Had the plastic ones

now for over 9 years, no problems. Mine are covered, so I don't know how they would do in UV rich sunlight.

Cheers,

rudi

No 300 series or Austenitc stainless steel is really suitable for iron rich well water...just not the Thai variety..

Thailand export hight quality stainless all over the world BTW

Without giving you a metallurgical lesson...Free iron (the iron in your well water) breaks down the Chromium oxide layer in the stainless (this is the bit of the stainless which makes it stainless) and causes pitting in the material because the iron prevents the oxide layer from "healing itself (this is a very simplistic way of explaining it, if you want the formula for the actual reaction I will send it to you gladly)

You will have dirty brown/black marks on the stainless, this is free iron contamination and eventually your tank will have holes in it..

If you catch it before it gets to far you can restore the surface condition of the stainless by a method called pickling and passivation which restores the chromium oxide layer...I am not going any further as to how do this and the chemicals involved, as it is quite a dangerous process if you dont know what you are doing, as it involves acids and not going to be responsible for some idiot trying it not knowing what they are doing.

Of course before undetaking this process you need to sort out your free iron problem in your water otherwise back to square one.

and other one to watch out for....Brackish or salty water and 304/304L stainless....something called SCC...stress corrosion cracking..no come back from this one..chuck your tank away...its knackered...

In conclusion if one is expecting high iron in the water....plastic or fibreglass tanks are better options provided the material is UV protected.

Stainless is a wonderful material but treat it wrong it will fail at some point

This concludes Professor Soutpeels materials science lesson for today...

Next week boys and girls we shall discuss the properties of Duplex and super duplex type stainless steels

Edited June 1, 2012 by Soutpeel

[luudee]

Thanks for the explanation Soutpeel !

It was a stupid oversight on my side. I actually fully know and understand the

chemistry involved ...

Back than I did not know that I had iron rich water, and stupid me didn't think

about testing the well water. It was not until we build our pool and filled it up

from the well. The first batch of chlorine turned it pitch black. That's when it

occurred to me that there must be lots of iron in the water

By that time the tanks where leaking already ... If any of the rice-farmers, ahm

I mean, highly qualified workers I had hired would have told me about the big

warning sticker in Thai not to use the tanks with well water, I would have saved

a lot of hadaches and money. Mai pen rai, mai me pehn-ha .... dhuuu

I guess the lesson here is, don't make any assumptions, no matter how trivial

it might seem (and learn to read thai) !

Cheers,

rudi

[Soutpeel]

Thanks for the explanation Soutpeel !

It was a stupid oversight on my side. I actually fully know and understand the

chemistry involved ...

Back than I did not know that I had iron rich water, and stupid me didn't think

about testing the well water. It was not until we build our pool and filled it up

from the well. The first batch of chlorine turned it pitch black. That's when it

occurred to me that there must be lots of iron in the water

By that time the tanks where leaking already ... If any of the rice-farmers, ahm

I mean, highly qualified workers I had hired would have told me about the big

warning sticker in Thai not to use the tanks with well water, I would have saved

a lot of hadaches and money. Mai pen rai, mai me pehn-ha .... dhuuu

I guess the lesson here is, don't make any assumptions, no matter how trivial

it might seem (and learn to read thai) !

Cheers,

rudi

Typically the problem with iron in water is trying to determine which type of contamination you have, as far as I am aware (I am no expert on water treatment) there are 3 types of iron "contamination" with 3 different approaches for removal if you in fact decided to try and "purify" the water

[overherebc]

Thanks for the explanation Soutpeel !

It was a stupid oversight on my side. I actually fully know and understand the

chemistry involved ...

Back than I did not know that I had iron rich water, and stupid me didn't think

about testing the well water. It was not until we build our pool and filled it up

from the well. The first batch of chlorine turned it pitch black. That's when it

occurred to me that there must be lots of iron in the water

By that time the tanks where leaking already ... If any of the rice-farmers, ahm

I mean, highly qualified workers I had hired would have told me about the big

warning sticker in Thai not to use the tanks with well water, I would have saved

a lot of hadaches and money. Mai pen rai, mai me pehn-ha .... dhuuu

I guess the lesson here is, don't make any assumptions, no matter how trivial

it might seem (and learn to read thai) !

Cheers,

rudi

Typically the problem with iron in water is trying to determine which type of contamination you have, as far as I am aware (I am no expert on water treatment) there are 3 types of iron "contamination" with 3 different approaches for removal if you in fact decided to try and "purify" the water

Another problem is the overheating of the weld in stainless when welded by ,cutting rice yesterday and and welding stainless today group.

As you will know leaves a nice band of non-stainless along each side of the weld, Most of the leaks and problems I've seen are either at the welds or around the fitting welds where the thoughts are, put a few more runs on and it will be ok, this actually makes it worse.

[Soutpeel]

Thanks for the explanation Soutpeel !

It was a stupid oversight on my side. I actually fully know and understand the

chemistry involved ...

Back than I did not know that I had iron rich water, and stupid me didn't think

about testing the well water. It was not until we build our pool and filled it up

from the well. The first batch of chlorine turned it pitch black. That's when it

occurred to me that there must be lots of iron in the water

By that time the tanks where leaking already ... If any of the rice-farmers, ahm

I mean, highly qualified workers I had hired would have told me about the big

warning sticker in Thai not to use the tanks with well water, I would have saved

a lot of hadaches and money. Mai pen rai, mai me pehn-ha .... dhuuu

I guess the lesson here is, don't make any assumptions, no matter how trivial

it might seem (and learn to read thai) !

Cheers,

rudi

Typically the problem with iron in water is trying to determine which type of contamination you have, as far as I am aware (I am no expert on water treatment) there are 3 types of iron "contamination" with 3 different approaches for removal if you in fact decided to try and "purify" the water

Another problem is the overheating of the weld in stainless when welded by ,cutting rice yesterday and and welding stainless today group.

As you will know leaves a nice band of non-stainless along each side of the weld, Most of the leaks and problems I've seen are either at the welds or around the fitting welds where the thoughts are, put a few more runs on and it will be ok, this actually makes it worse.

What you appear to be talking about is called heat tinting, the heat of the weld pool dissociates the chromium/Nickle and iron and basically you get free iron in the weld...heat tinted areas will eventually go brown/black and rust....welding over them will do nothing..on completed welds you need to undertake pickling and passivation of the weld..if not done...welds will go rusty....

[overherebc]

Chromiun carbide formation when the heat goes above 900 F for too long and is not cooled quickly enough after welding.

Don't want to go into all the technical or chemical details, just to point out to people to take a look at the tanks before you buy. If you see a line of little black or brown dots on the surface of the stainless either side of the welds it's a pretty good sign that it will sttart rusting through soon after you buy it

[Soutpeel]

Chromiun carbide formation when the heat goes above 900 F for too long and is not cooled quickly enough after welding.

Don't want to go into all the technical or chemical details, just to point out to people to take a look at the tanks before you buy. If you see a line of little black or brown dots on the surface of the stainless either side of the welds it's a pretty good sign that it will sttart rusting through soon after you buy it

Carbide formation is what is called weld decay...in stainless...decay and tint are "similar" in some respects, but not the same..the black and brown dots are free iron coming out of solution with in the alloy, but you dont need carbide formation to occur to get free iron to dissociate from the other main elements namely Chromium and Nickel in your 300 series type materials

Anyway not going any further as we are getting into detailed metallurgy, which will bore the shi8t out of people... other than to say both heat tint and iron comtamination can be "repaired" if havent gone too far as regards corroding....give away is brown and black spots or dirty marks on the stainless..wet black spots on stainless are usually indicative of active corrosion cells in the stainless (ie pitting)

Carbide formation/weld decay cannot be fixed per se

[haveaniceday]

Slightly off subject, but not worth a new thread, anyone know the cost for those concrete water tanks, I am guessing about 1000l or so, narrow at the bottom & wide a the top, like in these links.

http://www.huahinafterdark.com/forum/userpix/35_Water_butts_to_catch_rainwater_from_the_roof_1.jpg