steel cylinder rust

[erikfri]

everybody knows that cylinder internal rust is not good ...but does cleaning it improves the situation???

heavy rust will make it imposible for visual inspection and therefor should be cleaned.
external rust should be totaly cleaned and then coated and painted to prevent the on going process of rusting,on the other hand internal cylinder after cleaning doent get any painting!

if rust is not too heavy to prevent visual inspection ability should it be taken off? what is the purpos of scratching it off?
does rusty cylinder becomes safer after cleaning??
does rust bring more rust?
why not just dry ?

[luis]

Rust can trap moisture that will cause more rust and then pitting. Inside a cylinder the air is supposed to be very dry which would mitigate this issue… the key word is “should”.

Even very dry air is not that dry if you store a full cylinder in cold (32 F or below) location.

Any possibility of having loose rust should definitely be cleaned. You want to avoid having any loose particles inside the tank.

Mild surface rust is not much of an issue.


I have rotating tank wire brushes and whips that I use to clean and polish the inside surface of my cylinder. A polished surface provides a lot less surface area to trap moisture and less surface area to start any new rust.

[phsdive]

I also use whips and bottom brush for cleaning the inside of steel cylinders. After cleaning off the light rust I use an o2 clean rust inhibitor. Rinse the tank with hot water, then rinse with rust inhibitor (diluted and mixed with hot water so that it will dry quicker). Then blow some clean air in it as well to dry it off. If you have the time the whips are easy to make, just strands of stainless wire fixed to a long piece of 3/8 brass / metal. Just attach to a drill and insert into the tank (be careful of the valve thread - I use a piece of plastic to protect the thread.) If it is anyting other than light rust you need to get the tank rumbled.

[luis]

I just blow the rust dust off with high pressure air.


I only get the inside of my tanks wet during a hydro and then I also use high pressure air to dry it. As soon as I empty the water I use high pressure air in a 1/4" rigid tube to reach the bottom of the tank. I do it with the tank up-side-down. In less than 30 seconds the tank is totally dry and there has been no chance of any flash rust from forming.

The trick is that I don't empty the water out of the tank until I am ready to blow it dry. As soon as it is empty I blow it dry.

With this procedure I have never needed rust inhibitors or hot water. I just literally air blast the water/ moisture out of the tank. It works great.