Supplies for O2 cleaning a steel tank?

[Divin'Papaw]

Here is the price I was quoted for Ensolv

Container Size Fill Weight Price/lb. Total Price

1 Gallon 11 lbs. $6.00 $66.00

5 Gallons 55 lbs. $4.10 $225.50

30 Gallons 326 lbs. $3.73 $1,215.98

55 Gallons 600 lbs. $3.33 $1,998.00

FOB: Melrose Park, IL


Jim Breslin

Same prices I was quoted. Not sure what the shipping charges would be.

 

[oxyhacker]

As I understand it, Enslov is not an inhibitor at all. An inhibitor is something that prevents rusting - not just something that doesn't cause rust itself. Since once Ensolv is evaporated, it's all gone, it can't have any lasting anti-rust benefits. Just as well, the way I see it - tank cleaning agents that have rust inhibitive effects must also be leaving a residue (the way Blue Gold does), and I don't want chemical residues in my tanks.

Another problem with using solvents instead of water is that, since they are expensive, one tends to try to use as little as possible, which can lead to comtaminants being redeposited on the inside of the tank as the residual solvent evaporates (or even worse, reusing the solvent, which eventually can lead to the wash leaving the tank dirtier than it was to start with!). With water, one is free to stick a hose up in the tank and leave it running long enough to completely remove any residue.

My feeling is that Ensolv is cool stuff, but overkill for the purpose of routine O2 cleaning. Some warm water and a cheap home-made whip and a toothbrush will do just as good a job, and good rinsing/drying technique will prevent rusting.

Also I have my doubts about the wisdom of putting uncessary amounts of solvents into the air, even ones touted as benign.

Ensolv is also a rust inhibiter. Absolutely, no water involved at any time. Residual liquid evaporates completely. Blast a little compressed air to remove any remaining odor.

Those tech diving "agencies" don't know everything. I would never put water into a steel SCUBA tank unless it involved hydro testing. No choice there.

 

[Rick Inman]

...a cheap home-made whip and a toothbrush will do just as good a job...

I don't remember seeing this in your book. Can you elaborate on the construction of a toothbrush whip?

Thanks!

 

[JBRES1]

I'm not sure where I got it(the Deco stop), but I have used an acid wash to clean my tanks.
I used PHOSPHORIC ACID and water to clean out my steel cylinders.
I pre wash with crystal simple green and hot water.
I started of with a 5 gal batch of 500 oz water and 100 oz of 85% acid.
First wash was 4 parts water and 1 part mix, then a good flushing with water. I made up a wash flushing rod that is a 5ft long 5/8" copper pipe crimped at the end and that has holes drilled along the sides to spray the cylinder walls . I hook up this rod to a hose using a compression fitting , ball valve ,and a hose adaptor .The second wash was 8 parts hot water and 1 part mix , then blow dry. You do not rince the tank when using the 8 to 1 mix.
My cylinders look great on the inside(no flash rust), and have no smell of acid at all.

Jim Breslin

 

[crpntr133]

As I understand it, Enslov is not an inhibitor at all. An inhibitor is something that prevents rusting - not just something that doesn't cause rust itself. Since once Ensolv is evaporated, it's all gone, it can't have any lasting anti-rust benefits. Just as well, the way I see it - tank cleaning agents that have rust inhibitive effects must also be leaving a residue (the way Blue Gold does), and I don't want chemical residues in my tanks.

oxyhacker you might like to reread about Ensolv. Or am I not understanding you correctly?

 

[pescador775]

As I understand it, Enslov is not an inhibitor at all. An inhibitor is something that prevents rusting - not just something that doesn't cause rust itself. Since once Ensolv is evaporated, it's all gone, it can't have any lasting anti-rust benefits. Just as well, the way I see it - tank cleaning agents that have rust inhibitive effects must also be leaving a residue (the way Blue Gold does), and I don't want chemical residues in my tanks.

Read what the company says. Rust inhibition does not necessarily mean that a metal surface is painted over, merely modified (improved) to discourage rust.

ENVIRO Tech · EnSolv

Another problem with using solvents instead of water is that, since they are expensive, one tends to try to use as little as possible, which can lead to comtaminants being redeposited on the inside of the tank as the residual solvent evaporates (or even worse, reusing the solvent, which eventually can lead to the wash leaving the tank dirtier than it was to start with!). With water, one is free to stick a hose up in the tank and leave it running long enough to completely remove any residue.

This is the "people are too dumb to use it" theory. Nonsense.

Also I have my doubts about the wisdom of putting uncessary amounts of solvents into the air, even ones touted as benign.

I have doubts about your doubts. The "touting" is justified according to the EPA.

 

[pescador775]

About rust, it starts with water and oxygen in contact with ferrous metal like iron. However, for water vapor (a gas) to form droplets the water molecules need micro nuclei or a certain surface structure around which to coalesce and create miniature electrical cells. Washing metal with a powerful solvent like ENSOLV reduces the probability of this interaction, perhaps through interfering with electrical conductivity inside the cells or by polarizing potential sites for drop formation. Moreover, ENSOLV is an acid neutralizer, possibly a weak one but important for controlling rust spots under some situations which might occur inside a SCUBA tank, IMO. Such rust could be due to a process called catalytic conversion. This occurs when oil reacts with water in the presence of oxygen simultaneously in contact with a metal substrate. IOW, the solvent molecular film should inhibit it. However, it should be noted that ENSOLV liquid in contact with water may form acid so make sure the tank is dry before treatment. After treatment, the metal is partially protected (inhibited). Flash rust is characteristic of detergents which cause a sheeting action. ENSOLV won't allow this. This solvent does not evaporate completely. What remains is about 0.00001 percent of the original material. At the molecular level, this residue should be able to inhibit certain types of corrosion precursors as I explained. If I had to take a wild azzed guess, I might offer up this explanation. Solvent molecules are being held by atomic or mechanical forces within voids in the metal. It wouldn't surprise me if hydrophilic/corrosive constituents of detergents did the same thing but with harmful effect, perfume and that sort of thing but I don't know for sure. Otherwise, why would steel almost immediately show rust after cleaning? Commercial corrosion inhibiters work by creating a physical barrier to water contact thereby reversing the potential for damage caused by deterent, IMO.

 

[pescador775]

Rick, hacker is not talking about a "toothbrush" whip. He is referring to the common practice of cleaning threads with a toothbrush and soap. Of course, with ENSOLV, this uncertain practice is obviated. After pouring solvent, wrap the neck with masking tape. Invert the cylinder. If the threads are gunked up with silicone and dirt, leave inverted for a long time, like two minutes. LOL

For grins, here is one possible use for left over silly green. If mosquitoes frequent your locker or shop as they sometimes do mine, pour a mixture into a plastic bowl. Mosquitoes land in the stuff due to its unique aroma. However, low surface tension pulls them under, permanently. It is also possible that they are just being poisoned. I think it is the former but who knows?

 

[oxyhacker]

Nope, it's the "people are too cheap to use it right theory". One I have seen affirmed many, many times, as, I am sure, have you.

This is the "people are too dumb to use it" theory. Nonsense.

 

[pescador775]

I thought detergent was the cheapie way. Well, not if Global can help it, right?