Rusty muck in Reciever... how to treat???

[Sam0117]

I’ve had a similar thing with my receiver tank, I opted for electrolysis, stand the tank up on one end, and use a piece a steel as your rod, can’t remember if it’s the cathode or anode, 12V battery charger, tank negative and steel rod positive, fill your tank up with water and sodium carbonate and away it goes, got all the rust outta my tank, give it a few days and keep cleaning the steel rod every few hours then just jet wash your tank out once done and that’s it

 

[GRW]

I’ve had a similar thing with my receiver tank, I opted for electrolysis, stand the tank up on one end, and use a piece a steel as your rod, can’t remember if it’s the cathode or anode, 12V battery charger, tank negative and steel rod positive, fill your tank up with water and sodium carbonate and away it goes, got all the rust outta my tank, give it a few days and keep cleaning the steel rod every few hours then just jet wash your tank out once done and that’s it

Interesting. I've read bits on here about various techniques using electrolysis for de-rusting, making dip tanks and using.... stuff??... & while I kinda get the basic idea, it's the specifics as I've never seen one.
- I'm thinking that the Rod would have to be isolated from the Reciever body, for the current to flow through the fluid, yes?
- So, (as the corrosion is mainly in the bottom part of the cylinder) couldn't the Reciever be kept horizontal and flood it through the 2" aperture halfway up, then have the rod in a wooden bung in the same hole (inserted into the fluid of course)?
- I have a 10A intelligent 12v Charger. Would that do, or would it need to be an old style type? (If the latter there's an ancient transformer jobin work that does about 12A in either 12v or 24v? Would 24v be better than 12v?)
- what is the concentration of sodium carbonate needed.... and where does one obtain SC?
(Sorry for all the questions BTW..... but the technique sounds useful for other rusty reclamations and very handy to know how to do )
G.

 

[GRW]

Rust Removal Using Electrolysis

I found this, and it made sense to me & well-explained I thought.
I'm tempted to try this

 

[eddie49]

I have a 10A intelligent 12v Charger. Would that do?

I am fairly sure it won't.
Intelligent chargers usually need the 12v lead-acid battery to still be at a minimum voltage ( e.g. 8v ) before they will start to charge, they send variable-width current pulses, and they have a program to decrease the current as the battery voltage rises. You'll need an old-fashioned "dumb" transformer/rectifier unit.

 

[Seadog]

I cleaned and decreased as thoroughly as I could, then poured a lot of phosphoric acid in and moved the receiver around over a few days so that a exposed metal was contacted. Whether its done any good I've no idea.

 

[Alan Reynolds]

What about using this?

POR15 High Performance Fuel Tank Sealer 236ml 8oz - Stops and Seals Rust, Corrosion and Pin-Holes

 

[Bornfree]

just power wash it out they go rusty anyhow

This. My air receiver's get inspected every two years by the insurance company. And the chap who does it told me that he very rarely fails an old one. It's the 20 year old one's that mostly fail. The old ones are thicker gauge steel.

 

[Sam0117]

Interesting. I've read bits on here about various techniques using electrolysis for de-rusting, making dip tanks and using.... stuff??... & while I kinda get the basic idea, it's the specifics as I've never seen one.
- I'm thinking that the Rod would have to be isolated from the Reciever body, for the current to flow through the fluid, yes?
- So, (as the corrosion is mainly in the bottom part of the cylinder) couldn't the Reciever be kept horizontal and flood it through the 2" aperture halfway up, then have the rod in a wooden bung in the same hole (inserted into the fluid of course)?
- I have a 10A intelligent 12v Charger. Would that do, or would it need to be an old style type? (If the latter there's an ancient transformer jobin work that does about 12A in either 12v or 24v? Would 24v be better than 12v?)
- what is the concentration of sodium carbonate needed.... and where does one obtain SC?
(Sorry for all the questions BTW..... but the technique sounds useful for other rusty reclamations and very handy to know how to do )
G.

Yes the rod has to be isolated to the tank, I did it with just a block of wood and used a piece of 1” square box and drilled m8 hole and bolted a bolt through it to hold it and also tie the cable to it, not sure how I can link what I did to show you easier.

You could do just the bottom half if you rig the receiver right and the rod isolated too, maybe have like a main rod through and have smaller rods hanging off that?

Old style charger would be best, 24v would make it react quicker so wouldn’t need to stew as long, it leaves a black magnetite (could be wrong on the term) once it’s fully done. People have different opinions on the soda to water concrentration, for my 200L tank I used about 700g of it, you can get it from Tesco for cheap,

https://www.tesco.com/groceries/en-GB/products/258133332

Hope that helps

 

[slim_boy_fat]

@GRW Have you [or the other half ] got a wet vac?

 

[GRW]

@GRW Have you [or the other half ] got a wet vac?

Er...... no. But I can get my hands on one

 

[GRW]

Here's a pic of the mess that I managed to extract using a nail ripper jemmy bar to sort of rake the gack where I could see it and get at it through the 2" diameter threaded outlet boss (using an led inspection light and a telescopic magnet with a flexible end section).

I need to try to get into the harder-to-get-at areas a bit more and extract as much as I can. An unpleasant, awkward, stress-position task, but a necessary one.

 

[GRW]

What about using this?

POR15 High Performance Fuel Tank Sealer 236ml 8oz - Stops and Seals Rust, Corrosion and Pin-Holes

I looked that product up. Looks good, but instead that temps and humidity need to be north of 10 degrees and 60% consistently.... so here in soggy cold winter SW Wales I could only use this effectively for about 3 non-consecutive days in July or August

 

[Alan Reynolds]

I looked that product up. Looks good, but instead that temps and humidity need to be north of 10 degrees and 60% consistently.... so here in soggy cold winter SW Wales I could only use this effectively for about 3 non-consecutive days in July or August

Ah, just the ones without an R in then!

 

[GRW]

OK.... I've spent ages washing out the debris from the Reciever today, and picking out bits with a magnet and led torch.
I kept on rinse & repeating till I had only totally clear water running out of the drain (with a garden hose running from the nozzle stuffed up to the far end), picking up any bits washed down with the magnet.
Overall.... it looks pretty damned good in there. Of course there's pitting and corrosion evidence on the inside surfaces - but I've seen nothing that would make me concerned about the integrity of the Reciever. Phew!!

I have a (started but mostly full) 5L can of Scale-X phosphoric acid based, watery consistency stuff.
So, I'm thinking now to seal up and pressurise the tank a few times and purge to try and blow as much of the water moisture out - and then get some neat Scale-X and spray the inside as best I can (with the drain removed & open to allow excess to drain out instead of pooling inside.
Hopefully this will then convert the remaining corrosion and stabilise it, and help protect the Reciever for years to come (along with keeping the Compressor drained-down of course).

 

[GRW]

Well, I've sprayed the inside with phosphoric, then closed it up and pressurised it for a while (hoping it'd get spread all around the Reciever as it compressed), then vented the thing (outside) to expel any extra material.
Now I've got a small heat source inside the cylinder to dry up the interior.
Hopefully in a few days it'll be nice n dry and in good order, and I can fit a new high pressure direct outlet.

 

[Seadog]

Pressurising the receiver won't do anything. You need to swill it around.

 

[GRW]

Pressurising the receiver won't do anything. You need to swill it around.

I thought that might be the case. I did though spray the Reciever (using my little 50L compressor and gun), so hopefully it was pretty well covered by that anyway.
The Reciever looks a lot better cleaned out than I feared it could be - so this really is just an extra effort.

 

[bricol]

Well, I've sprayed the inside with phosphoric, then closed it up and pressurised it for a while (hoping it'd get spread all around the Reciever as it compressed), then vented the thing (outside) to expel any extra material.
Now I've got a small heat source inside the cylinder to dry up the interior.
Hopefully in a few days it'll be nice n dry and in good order, and I can fit a new high pressure direct outlet.

And the first time you use it . . . it'll be nice and wet inside

 

[GRW]

And the first time you use it . . . it'll be nice and wet inside

Yeah I know. I think I'd just like to see it dry just once before I close it all up

 

[Hog-Rider]

40 years ago when I was a maintenance Guy in a large Factory the first job of the week was the apprentice and myself had to go round the air receivers probably 100 plus some about 8 foot+ tall. We would take two empty 50 gallon oil drums on a cart and drain the water off. We would always fill about one and a half of the drums with horrible oily water. Then once a year we had a horrible task of cleaning the crap out the bottom of the tanks so the insurance man could inspect the inside of the receivers for damage /crakes etc, That was the worst job to carry out. At least it got some overtime in .Memories.